Dissertations / Theses: 'Ecological indicators'

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Bosman, Albé Cobus. "Ecological indicators for climate change." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/79275.

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The evidence of the effects of human mediated climate change is already evident in most ecosystems. The IPCC projects that there could be as much as a 4˚C increase in global average temperatures by the end of this century. In Mpumalanga the average temperature is projected to increase by as much as 2.8˚C, and annual precipitation levels by as much as 60 mm. Climate change, along with other human mediated factors such as land use changes and the over exploitation of natural resources, will lead to increasing pressures on biodiversity. Anthropogenic climate change will have significant impacts on biodiversity. These include impacts on distribution, abundance and ecological interactions. It is important to adopt biodiversity monitoring programs to understand the effects of anthropogenic climate change on the biota, which will enable best practice management and conservation of biodiversity. So far however, very few existing monitoring programs allow for the detection of climate change effects, as shown by the European project EuMon and the South African National Biodiversity Institute. In a cost-constrained world, the efficient use of resources for conservation has become crucial in ensuring the success of mitigating the effects of global change. Two methods of identifying indicators for the assessment of the effects of climate change on biodiversity were developed. The first method included the development of a pragmatic approach to the identification of suitable indicators and was tested in the Mpumalanga province. This approach identifies suitable species and ecosystem indicators, by subjecting candidate indicator candidates through a series of filters. The second method used a combination of climate and biodiversity data to identify indicators in areas of greatest and least climatic change within the Mpumalanga province. It is recommended that a combination of both methods be used, in order to be most useful in informing current and future monitoring programs.
Dissertation (MA)--University of Pretoria, 2015.
Zoology and Entomology
MSc
Unrestricted

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Porras, Macarena Mata. "Policy-relevant indicators for ecological agriculture." Thesis, Cranfield University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393694.

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Kostyuchenko, N. "Ecological-economic indicators for sustainability in Ukraine." Thesis, Вид-во СумДУ, 2005. http://essuir.sumdu.edu.ua/handle/123456789/19880.

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Benejam, Vidal Lluís. "Fish as ecological indicators in Mediterranean freshwater ecosystems." Doctoral thesis, Universitat de Girona, 2008. http://hdl.handle.net/10803/7873.

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L'objectiu d'aquesta tesi és contribuir a l'ús dels peixos continentals com a indicadors de l'estat ecològic a la conca Mediterrània. En el primer treball es va detectar que encara que tots els índex biològics estaven correlacionats significativament, els peixos integren i expressen els estressos de manera i a una escala diferents, aportant una informació complementària als altres índexs. Al segon article es van estudiar els cabals de sis conques catalanes. S'ha mostrat que els règims hídrics estan alterats amb una tendència a la disminució del cabal i del nivell dels aqüífers. S'ha detectat quatre mètriques de peixos que es troben significativament afectades en zones més castigades per manca d'aigua degut a l'activitat humana. Es discuteix la necessitat de conèixer en profunditat el règim hídric de cada conca abans d'utilitzar els índex biològics. Al tercer article es va detectar que la composició d'espècies capturades va variar significativament al llarg del buidat amb un augment de l'alburn (A. alburnus) a les aigües pelàgiques durant els dies de pitjor qualitat de l'aigua, confirmant que l'alburn és més tolerant a la mala qualitat de l'aigua que la madrilleta vera (R. rutilus) i suggereix el seu potencial com a bioindicador. La condició d'aquestes dues espècies va canviar significativament al llarg del buidat de manera molt estreta amb la qualitat de l'aigua. Al quart capítol es va estudiar la biologia dels peixos d'un embassament altament contaminat (Flix). El percentatge de DELT anomalies i la presència de paràsits externs era major en la zona impactada que als punts de control i els valors més alts de pes eviscerat i pes del fetge estaven als punts de control. Les respostes van ser diferents per cada espècie i la carpa va ser la que va mostrar més clarament els impactes.
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The aim of this thesis is to contribute to the use of freshwater fish as ecological indicators in the Mediterranean basin. In the first article we found that although most biological indices were correlated, fish reflected different ecological aspects due to their particular features. In the second article the stream flow regimes of six Mediterranean basins were studied. A decrease of streamflow and aquifer levels was detected, despite no observed decrease of rainfall precipitation. Of the thirty metrics tested to detect sites impacted by water abstraction, we detected four significant fish metrics. Furthermore, the role of biotic indices when the river is artificially dry is discussed. In the third article we found that species composition in the pelagic zone varied significantly during the drawdown with higher proportion of bleak (A. alburnus) during the days of worst water quality, confirming that bleak is more tolerant than roach (R. rutilus) to poor water quality. The weight-length relationship of roach and bleak also varied significantly during the drawdown with close relationship between water quality and fish condition. In the fourth article the condition and fecundity of freshwater fishes were assessed in a highly polluted reservoir (Flix reservoir). We have shown significant increases of DELT anomalies and ectoparasite prevalences and decreases in condition and fecundity of several freshwater fish at the impacted area. The responses to the pollutants were species-specific and common carp was the species that showed more markedly the effects.

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Yu, Sherman, and 余雪雯. "A study of sustainability indicators: Hong Kong's ecological footprint." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31228057.

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Jennings, Isabella. "Cities as sustainable ecosystems : ecological footprints and other indicators." Thesis, Jennings, Isabella (2003) Cities as sustainable ecosystems : ecological footprints and other indicators. Honours thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/38394/.

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As concerns mount about the impact of human activities on the biosphere, cities are in the frontline of initiatives to change the course of human society onto a more sustainable path. This thesis seeks to make clear the foundations of the concept of Cities as Sustainable Ecosystems, and to develop a set of indicators to chart a more sustainable course. To achieve this, the concept of sustainabllity; the characteristics and strategies of sustainable ecosystems and sustainable societal-ecological systems; the dynamics of current cities; and a range of indicator approaches, were investigated through a review of literature, including texts, journals and online resources. From this a sustainability assessment tool was devised to apply the ideas and indicators at a subdivision level, and it was used in two case studies of new urban developments in Perth, Western Australia. The concept of Cities as Sustainable Ecosystems offers the opportunity to integrate various sources of wisdom to provide guidance in rebuilding connections between people, between people and place, and in designing integrated systems, based on the characteristics and strategies of sustainable systems. A major conclusion of this research is that cities need to be viewed as part of their bioregions, and their ecological footprints need to match their bioregions. Indicators provide feedback about progress towards sustainability. They are most powerful when they are devised by communities working with experts. Crucial too is the visibility of ecological processes in cities as well as linkages to the bioregion, providing immediate and tangible indicators feedback to complement quantitative indicators. Response indicators such as the degree of civic participation provide some of the strongest signs of future improvements or decline. The sustainability assessment tool represents an attempt to provide a systemic approach to the assessment of urban developments, and to identify issues that need to be considered in the design.

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Gilfillan, Dennis, Kimberlee Hall, Timothy Andrew Joyner, and Phillip R. Scheuerman. "Canonical Variable Selection for Ecological Modeling of Fecal Indicators." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5479.

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More than 270,000 km of rivers and streams are impaired due to fecal pathogens, creating an economic and public health burden. Fecal indicator organisms such as Escherichia coli are used to determine if surface waters are pathogen impaired, but they fail to identify human health risks, provide source information, or have unique fate and transport processes. Statistical and machine learning models can be used to overcome some of these weaknesses, including identifying ecological mechanisms influencing fecal pollution. In this study, canonical correlation analysis (CCorA) was performed to select parameters for the machine learning model, Maxent, to identify how chemical and microbial parameters can predict E. coli impairment and F+-somatic bacteriophage detections. Models were validated using a bootstrapping cross-validation. Three suites of models were developed; initial models using all parameters, models using parameters identified in CCorA, and optimized models after further sensitivity analysis. Canonical correlation analysis reduced the number of parameters needed to achieve the same degree of accuracy in the initial E. coli model (84.7%), and sensitivity analysis improved accuracy to 86.1%. Bacteriophage model accuracies were 79.2, 70.8, and 69.4% for the initial, CCorA, and optimized models, respectively; this suggests complex ecological interactions of bacteriophages are not captured by CCorA. Results indicate distinct ecological drivers of impairment depending on the fecal indicator organism used. Escherichia coli impairment is driven by increased hardness and microbial activity, whereas bacteriophage detection is inhibited by high levels of coliforms in sediment. Both indicators were influenced by organic pollution and phosphorus limitation.

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Gilfillan, Dennis, Kimberlee Hall, Timothy Andrew Joyner, and Phillip Scheuerman. "Canonical Variable Selection for Ecological Modeling of Fecal Indicators." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5589.

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More than 270,000 km of rivers and streams are impaired due to fecal pathogens, creating an economic and public health burden. Fecal indicator organisms such as Escherichia coli are used to determine if surface waters are pathogen impaired, but they fail to identify human health risks, provide source information, or have unique fate and transport processes. Statistical and machine learning models can be used to overcome some of these weaknesses, including identifying ecological mechanisms influencing fecal pollution. In this study, canonical correlation analysis (CCorA) was performed to select parameters for the machine learning model, Maxent, to identify how chemical and microbial parameters can predict E. coli impairment and F+-somatic bacteriophage detections. Models were validated using a bootstrapping cross-validation. Three suites of models were developed; initial models using all parameters, models using parameters identified in CCorA, and optimized models after further sensitivity analysis. Canonical correlation analysis reduced the number of parameters needed to achieve the same degree of accuracy in the initial E. coli model (84.7%), and sensitivity analysis improved accuracy to 86.1%. Bacteriophage model accuracies were 79.2, 70.8, and 69.4% for the initial, CCorA, and optimized models, respectively; this suggests complex ecological interactions of bacteriophages are not captured by CCorA. Results indicate distinct ecological drivers of impairment depending on the fecal indicator organism used. Escherichia coli impairment is driven by increased hardness and microbial activity, whereas bacteriophage detection is inhibited by high levels of coliforms in sediment. Both indicators were influenced by organic pollution and phosphorus limitation.

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Deeley, D. M. "Evaluating indicators of ecological health for estuaries in southwest Australia." Thesis, Deeley, D.M. (2001) Evaluating indicators of ecological health for estuaries in southwest Australia. PhD thesis, Murdoch University, 2001. https://researchrepository.murdoch.edu.au/id/eprint/3371/.

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A broad range of environmental indicators were evaluated to determine their suitability for describing the early onset of nutrient enrichment in south-west Australian estuaries. The southwest of Australia experiences a Mediterranean climate with hot dry summers and cool wet winters. Most of the south-west estuarine catchments have been extensively cleared for agricultural and urban development and have been loosing unacceptably high loads of nutrients. Symptoms of nutrient enrichment have been observed in many south-west estuaries. An evaluation of fifty years of historical water quality data defined the range of normal behaviour for these systems together with the nature of rarer extreme events. It was found that south-west Australian estuaries are highly variable in space and time and appear to be more susceptible to nutrient enrichment than those observed elsewhere in Australia. While there may be significant fluctuations in physico-chemical conditions and the structure of biological communities in ecosystems subjected to natural variability and anthropogenic stressors, it is possible that the junction of biological communities in these situations is less affected by these types of perturbations. Several indicators of biological function (rates and processes) were developed and evaluated to determine whether they offered a greater degree of diagnostic precision (early warning) than measures of stocks and status (inventory). In evaluating various environmental indicators, it was found that no single indicator was able to unambiguously define the interactions between physic-chemical and biological processes and the response of these systems to anthropogenic and natural stressors. It has been concluded that a broad range of potential indicators must be evaluated simultaneously, in order to define baseline conditions, measurement endpoints and trends to inform catchment and estuarine management and restoration. Increased confidence in the selected indicator suite can flow from an evaluation of the monotonicity of correlated indicators, especially when assessments show consistent patterns for physico-chemical measures and measures of biotic community structure across several trophic groups. Traditional physic-chemical indicators have provided reliable information in me past, but problems have arisen when relating these measures to biological endpoints, particularly for estuaries with significant seasonal and inter-annual variability. In the absence of biological data for estuarine ecosystems experiencing significant seasonal and inter-annual variability, socio--economic indicators of catchment land use practices may be the only option. Paleolimnological investigations may also provide additional insight into patterns of natural variability over the longer term, but the degree of taxonomic resolution required and requirements for supporting stable isotope analysis, may consume considerable resources. Autotrophic protistans (periphyton, phytoplankton), appear to be useful for describing nutrient enrichment, salinity and other physico-chemical conditions, but complicating factors such as the nature of coupling of secondary predation need to be identified. Autecology of local indicator species also needs to be defined. Zooplankton appear to be limited as environmental indicators, but because of their potential role in grazing and materials transfer, they may be useful as elements of biotic indices across several trophic groups. One of the major impediments to using planktonic organisms for inferring the condition of estuarine health is the considerable vertical, horizontal and temporal heterogeneity displayed by these organisms in both disturbed and undisturbed systems. More recently, benthic macro-invertebrates have been successfully used to describe the nature and magnitude of organic enrichment of estuaries. Community structure, biomass and relative abundance of functional groups and indicator species have also been developed and used as environmental indicators. Problems may occur in the use of these organisms to infer health in south-west estuaries because of the presence of naturally immature communities and variable colonization dynamics where there is significant seasonal and inter-annual variability. Inventory measures of community structure have problems because of a lack of information about exchange pathways connecting system components and unknown interactions between diversity, stability and resilience of the ecosystem. Species richness, diversity indices and measures of biomass have probably been the most widely used indicators in the majority of published works, but generally without appropriate critical analysis of their utility. Biomass appears to have less inter-annual variability than do other measures of community structure. A myriad of biotic indices (ratios of functional groups) within and across trophic levels have been described in the international literature. There are problems in defining weightings and concordance methods for elements contributing to biotic indices and the loss of valuable information during these types of data reduction limit their potential. Detailed autecology of members of functional groups are required for biotic indices and this type of information is potentially available for some cosmopolitan species, but generally lacking for endemic species which may describe important nuances of the local environment. As with biotic indices, there is a range of combined metrics described in the literature. Metrics generally combine physico-chemical elements, and may include some biological information. Many of the problems with biotic indices apply equally to metrics, but when calibrated for a particular local situation, they offer considerable discriminatory power. Assessment of early colonisation dynamics and the responsiveness of periphyton communities to nutrient additions provided insights into some key processes in south-west estuaries. Periphyton communities in estuaries with a past history of nutrient enrichment responded well to nutrient additions while communities in less disturbed estuaries did not respond as readily. This infers that opportunistic species able to respond rapidly to nutrient additions may become established in estuaries having a nutrient enrichment history while they may be less able to maintain a viable presence in less enriched estuaries. While showing promise, additional testing and refinement of these process indicators would better define their potential as early warning indicators of nutrient enrichment for south-west estuaries. For describing the ecological health of south-west Australian estuaries, physico-chemical indicators of catchment and estuarine water quality and socio-economic measures of catchment land use history may be of use. If assumptions about the linearity of interactions between the diversity of biotic communities and the stability and resilience of ecosystem function are valid, then conventional measures of community structure will also provide useful insights. The ongoing selection, evaluation and refinement of environmental indicators for assessing the ecological health of south-west Australian estuaries, needs to proceed as a close partnership between land and waterway managers and scientific specialists.

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Alves, Paula Rute Pereira Matono. "Fish assemblages as biological indicators of ecological quality in portuguese rivers." Doctoral thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/16172.

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No contexto da aplicação da Directiva-Quadro da Água, a ictiofauna é considerada como um relevante elemento biológico. Pela primeira vez foi desenvolvido um sistema de classificação para avaliação do estado ecológico dos ecossistemas aquáticos em Portugal, apesar dos constrangimentos impostos pela variedade e ubiquidade das pressões humanas e pelas peculiaridades dos agrupamentos piscícolas. Foram definidos grupos piscícolas para posterior estabelecimento de uma tipologia nacional de rios, foram seleccionadas métricas responsivas ás pressões humanas e foi desenvolvido um índice biótico piscícola. Os resultados evidenciam a necessidade de diferenciar correctamente a resposta da ictiofauna ás perturbações naturais e antropogénicas, considerando quer a variabilidade espacial, quer temporal dos agrupamentos piscícolas, típica dos cursos de tipo Mediterrânico. O uso de solo tem fortes consequências na degradação dos rios e na integridade da ictiofauna, sendo importante que a avaliação dos impactos considere a interacção entre diferentes pressões. A compreensão da influência relativa dos factores ambientais e humanos na ocorrência e abundância das espécies não nativas permitiu evidenciar o potencial papel das mesmas como indicadores biológicos. Esta tese contribuiu para o desenvolvimento e aperfeiçoamento de ferramentas de avaliação ecológica em Portugal, permitindo igualmente um aumento do conhecimento sobre a ecologia das comunidades piscícolas e funcionamento dos ecossistemas em rios de tipo Mediterrânico, com vista à sua conservação e reabilitação; ABSTRACT:Under the implementation of the Water Framework Directive fish fauna is considered a useful biological element. For the first time a Portuguese classification system to assess the ecological status of aquatic ecosystems was established, despite several constrains posed by the variety and ubiquity of human pressures and by the peculiarities of the fish assemblages. It was possible to define fish-based geographical groups for the subsequent establishment of a national river typology, to select metrics responsive to human pressures and to develop a fish biotic index. Results underline the needs for accurately differentiate between fish responses to natural and anthropogenic disturbances by accounting for the spatial and temporal variability of fish assemblages. Land use may lead to strong impacts on stream degradation and fish assemblages integrity and this evaluation must consider the interaction of different pressures. Understanding the influence of environmental and human factors in the occurrence and abundance of non-native species enlightened their role as a reliable tool in the ecological assessment of rivers. This thesis represents an important contribution to improve the ecological assessment tools in Portugal, while increasing knowledge on the ecology of fish communities and ecosystem functioning in Mediterranean climate rivers in view of their urgent conservation.

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Roosa, Benjamin. "Soil Indicators of Restored Ecological Function Following Riparian Afforestation in Southern Illinois." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2452.

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Over the last 30 years, Crab Orchard National Wildlife Refuge in Southern Illinois has made a strong and well-documented effort to convert agricultural lands to forest to further their mission of wildlife and habitat conservation. Our research seeks to assess the influence that this land use conversion has on ecological function and to establish ecological indicators of successful restoration. We examined five potential soil-based indicators of ecological function across a chronosequence of afforested sites at the refuge and compared them to nearby row crop agricultural sites and mature forest sites with similar soils and landscape positions. Collected soil samples were analyzed for total carbon, total nitrogen, labile carbon, aggregate stability, and bulk density. Soil texture analysis was also conducted to validate comparisons among sites. The data were analyzed using a multivariate analysis of variance comparing land uses as well as linear regression analyses looking at the influence of age since restoration on an index value created by subtracting the soil indicator value of the nearby agricultural site from that of the forested site. The index value was used as the dependent variable in order to control for variation among sites and isolate the influence of age. Aggregate stability and labile carbon were positively correlated with age since restoration and bulk density was negatively correlated with age since restoration. These three soil parameters were promising indicators of restored ecological function in afforested sites. Target values for these indicators were proposed. Our results help to determine the timeframe in which these ecological functions return following restoration and can be used to assess the success of current and future afforestation projects.

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Matos, Paula Sofia Antunes. "Development of ecological indicators of climate change based on lichen functional diversity." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16833.

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Doutoramento em Biologia e Ecologia das Alterações Globais
Growing evidence shows us that climate has changed in the recent decades, and the scenario for the future will most likely worsen. A set of climate variables is being developed to monitor climate change, but this is not enough to keep track its effects on ecosystems. It’s imperative to understand and quantify how ecosystems functioning are affected by and respond to these changes, and ecological indicators based on biodiversity metrics are one of the tools to do this. The objective of this work was to develop a global lichen functional diversity integrated ecological indicator of the effects of climate change on ecosystems. For that, we used a climatic gradient in space assuming a space-for-time proxy. To be global, we developed a framework to jointly analyse data from the two methodologies currently used at the continental scale (US and EU). Afterwards, we found that lichen traits, main type of photobiont, growth form and size respond to climate, namely to the range and seasonal variation of temperature and precipitation, and to relative humidity. However, the response was specific for each functional group (e.g. cyanolichens) showing that traits (e.g. photobiont) as a whole do not respond universally to the same climate variables. Then, we confirmed that each functional group reflected the underlying climate variables in a predictable way, validating their use as ecological indicators of climate change. Once our approach was not limited by species identity, we tested its potential to be used at a global scale. We found that each couple of functional group and underlying climatic variable cannot be applied at the global scale; the response is specific to areas with the same climatic limiting factor (ex: water availability). Because lichen functional groupbased indicators respond to the most limiting climate factors, and these vary as we move on the globe, its application must be specific to areas with similar climate limiting factors. Finally, we wanted to understand if the space-for-time proxy was valid. The ecological indicators previously found using a spatial approach for a specific climate were in fact those responding to climate shifts over fifteen years. Moreover, these indicators were able to respond to subtle shifts in climate no yet depicted by classic climate metrics. Thus lichens are in fact excellent ecological indicators to track the effects of climate change, and have the potential to be early warning. International organizations such as the Unite Nations three sister conventions have long demanded for a set of ecological indicators to track the effects of climate change, that can be monitored continuously over time. From now on, lichens can be included in this set of ecological indicators and we expect that this work will foster lichen functional diversity use as a tool to track climate change worldwide.
O clima global tem vindo a mudar ao longo das ultimas décadas e um conjunto de variáveis climáticas está a ser desenvolvido para monitorizar estas alterações climáticas. No entanto, isso não é insuficiente. É imperativo compreender e quantificar como o funcionamento dos ecossistemas é afetado e responde a estas alterações, e os indicadores ecológicos baseados na biodiversidade são uma das ferramentas para o fazer. O objectivo deste trabalho foi desenvolver um indicador ecológico global e integrado baseado na diversidade funcional de líquenes, para avaliar os efeitos das alterações climáticas nos ecossistemas. Para isso usamos um gradiente climático no espaço, assumindo o espaço-pelo-tempo como proxy. Para ser global, desenvolvemos um enquadramento de análise conjunta dos dados das duas metodologias de amostragem de líquenes usadas à escala continental (EUA e EU). De seguida, mostramos que os atributos funcionais de líquenes relacionados com o tipo de fotobionte, forma de crescimento e tamanho respondem ao clima, nomeadamente à amplitude e variação sazonal da temperatura e precipitação e à humidade relativa média anual. No entanto, a resposta foi específica para cada grupo funcional (p.e. cianolíquenes) mostrando que os atributos funcionais no seu todo (p.e. tipo de fotobionte) não respondem universalmente às mesmas variáveis climáticas. De seguida, confirmamos que cada grupo funcional refletiu as variáveis climáticas subjacentes de forma previsível, validando o seu uso como indicadores ecológicos. Porque esta abordagem não foi limitada pela identidade das espécies, testamos a sua aplicação à escala global. Descobrimos que os pares grupo funcional/variável climática subjacente não podem ser aplicados à escala global; a resposta é específica de áreas com o mesmo factor climático limitante (p.e. água). Porque respondem ao factor climático mais limitante e este varia à medida que nos movemos no globo, a sua aplicação tem que ser especifica a áreas com os mesmos factores climáticos limitantes. Finalmente, tentamos compreender se o proxy espaço-pelo-tempo usado era válido. Os indicadores ecológicos previamente identificados ao longo de um gradiente climático espacial, foram os que responderam a mudanças climáticas ao longo de 15 anos e esta resposta foi sensível a mudanças subtis no clima, não detetadas pelas métricas clássicas de clima. Em conclusão, os líquenes são de facto excelentes indicadores ecológicos para avaliar os efeitos das alterações climáticas, com potencial de alerta precoce. Organizações internacionais como as três convenções irmãs das Nações Unidas há muito exigem um conjunto de indicadores para avaliar os efeitos das alterações climáticas, que possam monitorizar continuamente. De hoje em diante, os líquenes podem ser incluídos neste conjunto e esperamos que este trabalho fomente o uso da diversidade funcional de líquenes como uma ferramenta para avaliar e seguir os efeitos das alterações climáticas nos ecossistemas do mundo inteiro.

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Zetterberg, Andreas. "Network Based Tools and Indicators for Landscape Ecological Assessments, Planning, and Design." Licentiate thesis, Stockholm : Arkitektur och samhällsbyggnad, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10011.

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Kettner, Claudia, Angela Köppl, and Sigrid Stagl. "List of well-being indicators." European Commission, bmwfw, 2012. http://epub.wu.ac.at/4714/1/WWWforEurope_WPS_no002_MS30.pdf.

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This milestone presents a pool of available indicators and indicator systems which go beyond the narrow concepts of national economic accounts as well as a structuring of the indicators and indices according to central areas of well-being. The milestone builds the basis for Task 202.2, where a subset of indicators will be selected based on different theoretical frameworks, e.g. services / functionings, needs. Some of the indicators will be included in the macro-economic models in order to account for key dimensions of sustainability.
Series: WWWforEurope

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Nunes, Monique. "Microalgae and macrophytes as indicators of ecological health in the Great Brak Estuary." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1012097.

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The Great Brak temporarily open/closed estuary was subjected to a drought during the spring and summer of 2009/2010 resulting in the mouth remaining closed for a prolonged period. According to the Great Brak Estuary management programme, the mouth of the estuary had to be open for a total of 308 days during spring and summer of 2009/2010, respectively, but was closed for almost the entire two years (693 days). The aim of this study was to assess monthly changes in the abiotic characteristics (salinity, temperature, oxygen, pH and nutrients) and the biotic responses of phytoplankton and macroalgae; identify sources of nutrient input into the estuary and determine the response of the salt marsh to water level and salinity changes. The results indicated that physico-chemical parameters were similar to that previously recorded during the closed mouth condition. However mouth closure combined with elevated nutrient concentrations led to a shift from rooted submerged macrophytes to one where either microalgae or macroalgae were dominant. Soluble reactive phosphorus concentrations were significantly higher in bottom compared with surface waters. There was a significant negative correlation with SRP and dissolved oxygen for the sampling period indicating potential release of phosphorus from the sediment during closed mouth conditions. Microalgal biomass increased in response to remineralised nutrients and freshwater pulses. Flagellates were the dominant microalgal group (21718 ± 3336 cells m l-1, p < 0.05) because of their morphological ability to migrate vertically within the water column. The macroalgal cover was highest during the closed mouth state but only during winter (August 2010) when temperatures were below 20 oC. Five major point sources of nutrient input into the Great Brak Estuary were identified during rainfall periods. Point sources 4 and 5 in the upper reaches of the estuary had the highest DIN input whereas point source 3 in the middle reaches of the estuary had the highest DIP input. As a result of the drought and low water level, the salt marsh was never inundated for longer than 3 months. Die-back of Sarcocornia decumbens (r 2= -0.62, p < 0.05) was related to smothering by dead macroalgae whereas dieback of Sporobolus virginicus was related to decreasing nutrient (r2 = 0.59, p < 0.05) and salinity (r2 = 0.55, p < 0.05) levels. The physico-chemical characteristics alone did not convey the true health status of the Great Brak Estuary for the duration of the sampling (April 2010-April 2011). The study showed that microalgae and macroalgae are valuable indicators of the status of the estuary. Therefore it is suggested that bio-indicators are incorporated into the management/monitoring plan in order to assist in improving the health assessment of the Great Brak Estuary.

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Mörtberg, Ulla. "Landscape Ecological Analysis and Assessment in an Urbanising Environment - forest birds as biodiversity indicators." Doctoral thesis, KTH, Land and Water Resources Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3768.

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To achieve a sustainable development, impacts onbiodiversity of urbanisation, infrastructure, land use changesand other developments must be considered on a landscape andregional scale. Landscape ecology can provide a conceptualframework for the assessment of consequences of long-termdevelopment processes like urbanisation on biodiversity on alandscape scale, and for evaluating the impacts of alternativeplanning scenarios. The aim of this study was to explore theeffects of habitat quality, quantity and connectivity on forestbird diversity in an urban-rural gradient. The purpose of theanalyses was to develop knowledge and methods for integratingbiodiversity issues in planning and assessments in anurbanising environment, on landscape and regional scales.

The study area was situated in and around Stockholm, thecapital of Sweden, covering the city centre, suburbs andperi-urban areas. Data on breeding forest birds were collectedthrough bird censuses in an urban-suburban gradient. In orderto embrace also the peri-urban areas for a more completeurban-rural gradient, data on two fragmentation-sensitiveforest grouse species were obtained through a questionnaire tohunters in the whole study area. Response variables in theanalyses were forest bird species richness and diversity,relative species richness and occurrence of single sensitivespecies like selected sedentary forest birds, including theforest grouse species, and red list species. Habitat quality,quantity and connectivity were analysed using available data onabiotic conditions, including urban disturbances, andvegetation in geographical information systems. In addition, afield study on vegetation structure and composition wasperformed in a subset of the smaller sample sites.Relationships between the response variables and habitatquality, quantity and connectivity were explored usingstatistical methods like multivariate statistics and regressionmodelling. Further, for some models, spatial dependencies werequantified and accounted for. When habitat models wereretrieved, they were used for spatial predictions of habitatsuitability. They were also applied on future planningscenarios in order to predict and assess the impacts onsensitive species. In the urban-rural gradient, the foreststructure and composition changed, so that in more urban areas,coniferous forest on rich soils, wet forests and wetlandsbecame less abundant and more scattered. Sensitive birdspecies, tied to these habitat types, were shown to besensitive to habitat fragmentation caused by urbanisation.Large, well-connected habitat patches and aggregations ofsuitable habitat in the landscape had a higher probability ofoccupancy when compared to other patches. For the forest grousespecies, effects of car traffic added to the explanation oftheir distribution. By contrast, deciduous forest was stillquite common in predominantly urban areas, due to both latechanges in land use and a history of human preferences. Certainred listed bird species tied to deciduous forest did not seemto be affected by isolation, and also occurred in suitablehabitats in some highly urbanised areas. Furthermore, relativespecies richness in the urban-suburban gradient was related tomulti-layered deciduous forest habitats with a large amount ofdead wood. Such habitats were associated with natural shorelineand with old pastures and parks. From the derived statisticalmodels, describing the relationships between sensitive speciesand environmental variables, predictive habitat maps could becreated for the present situation and for planning scenarios.The predictions of the impacts on habitats of sensitive speciesmade it possible to quantify, integrate and visualise theeffects of urbanisation scenarios on aspects of biodiversity ona landscape scale.

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Маценко, Олександр Михайлович, Александр Михайлович Маценко, Oleksandr Mykhailovych Matsenko, and A. Y. Bavykina. "Approaches to the formation of socio-ecological and economic indicators of sustainable water usage." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33623.

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The beginning of the XXI century is accompanied by a powerful expansion of the global production of goods and services which leads to a catastrophic depletion of the world’s water resources. The international organisations dealing with the environmental protection pay attention to the problem of the sustainable water usage connected with the reduction of water supplies and assimilated capabilities of water in different ecosystems. Economy and the problem of water quality are quite relevant for Ukraine. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/33623

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Cobby, Graham. "A framework for indicators of rehabilitation success based on ecological principles and social values." Thesis, Cobby, Graham (1996) A framework for indicators of rehabilitation success based on ecological principles and social values. Masters by Research thesis, Murdoch University, 1996. https://researchrepository.murdoch.edu.au/id/eprint/40881/.

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To understand the meaning of rehabilitation success we need to address two fundamental questions: (1) what does rehabilitation success mean; and (2) how can rehabilitation success be measured? The research objectives of this dissertation are defined by these two questions...

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Busst, Georgina Marie Ann. "Fish scales as ecological indicators : empirical approaches to improve their practical application to fish ecology." Thesis, Bournemouth University, 2017. http://eprints.bournemouth.ac.uk/29484/.

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The collection of scales is common when fish communities are sampled within research and monitoring programmes in freshwater fisheries. Although used primarily to age individual fish, there is increasing evidence of their potential for application to other ecological methods, yet there is also considerable uncertainty in how this can be achieved. Thus, the purpose of this research was to examine how the use of scales within age and growth studies can be enhanced and investigate their application to freshwater trophic ecology, with a particular focus on advancing their utilisation within stable isotope analysis (SIA). The research used fishes of the Cyprinidae family as the focal species. Cyprinids are of substantial global, socio-economic importance as their communities are valued ecologically, commercially and recreationally. The research assessed current methodologies, highlighted extant gaps in knowledge and sought to resolve these issues. It covered work regarding the intrinsic error contained in estimating fish age from scales and improved scale application within SIA through the provision of key data that is currently lacking within the literature. An initial invasion ecology case-study provided new insights into the growth and trophic impacts of a model native and two non-native fishes under three distinct approaches of differing spatial scale and complexity. The results revealed a range of ecological consequences for the native species from the invaders, although the extent of these was also a function of spatial scale. Additionally, a number of procedural concerns relating to the collection of fish age data and current SIA methodologies were highlighted. The use of scales to derive estimates of the ages of fish is well established, with outputs used to address questions on aspects of fish and fisheries ecology, but the process remains prone to inherent errors. The research revealed that precision of growth estimates is significantly influenced by the sub-sampling regime applied. Where individuals are long-lived and slow-growing, sub-sampling strategies that result in few scales being analysed produced imprecise data and potentially erroneous outcomes. Additionally, uncertainty in the accuracy of ageing scales also potentially results from subjective interpretation of scale features. A statistical model was developed to incorporate this uncertainty into analyses, using Bayesian statistics and a bootstrapping methodology, to improve age and growth rate estimates. The model successfully produced error adjusted von Bertalanffy growth parameters. Food web and trophic analyses have traditionally been completed through stomach content analysis, but increasingly SIA is preferred, as it provides greater temporal perspectives and requires smaller sample sizes. In fish studies, dorsal muscle tissue is typically favoured, but this is often collected destructively. The research revealed that non-destructively collected tissues, such as scales, can act as a proxy for muscle and their isotopic values can be converted with minimal error when species-specific factors are used. When stable isotope data are applied to dietary studies, their use in statistical mixing models requires accurate step-wise enrichment values between diet and consumer (i.e. discrimination factors). There is considerable uncertainty in the variability of discrimination factors between species and the influence of their diet. Consequently, specific diet-tissue discrimination factors were produced for a range of cyprinid species and diet was shown to significantly affect diet-tissue discrimination. The application of species-specific values within mixing models can result in significant differences when compared with using standard values and consideration of the influence of diet needs to be made when investigating omnivorous species. The rate of turnover of carbon and nitrogen stable isotopes was also determined and variability between tissues was revealed, indicating that species- and tissue-specific half-lives should be considered when deciding upon experimental time-frames. In summary, the research has provided substantial information targeting extant knowledge gaps relating to the application of scales from cyprinid fishes to ecological studies. Regarding fish age and growth, issues surrounding accuracy and precision of estimates has been tackled, informing researchers of the influence on precision of applying sub-sampling regimes to subsequent growth analyses and providing an original statistical tool that can improve accuracy through producing growth parameters that better reflect inherent errors in fish age data. In contributing to the use of scales in SIA, novel data have been provided that will reduce the requirement for destructive sampling of fishes and enhance present understandings of the significance of species- and tissue-specific discrimination factors and turnover rates.

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Маценко, Олександр Михайлович, Александр Михайлович Маценко, Oleksandr Mykhailovych Matsenko, and A. Y. Bavykina. "Approaches to generate a system of socio-ecological and economic indicators of sustainable water use." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/31640.

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Beginning of the XXI century accompanied by a powerful expansion of global goods and services production which leads to a catastrophic depletion of the world’s water resources. These processes make the international organizations in the field of environmental protection to raise the issue of sustainable water use-not exceeding the reduction and assimilation capabilities of water ecosystems. Economy and water quality problems is quite relevant for Ukraine due to uncontrolled use of water resources, a large part of water loss, industrial ecosystems pollution. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/31640

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McKenna, David J. "Demographic and ecological indicators of rarity in a suite of obligate-seeding Persoonia (Proteaceae) shrubs." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080131.142010/index.html.

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22

Johnson, Ryan Allan. "Ecological indicators, historical land use, and invasive species detection in the lower Iowa River floodplain." Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4655.

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Alizadeh, Shabani Afshin, and afshin alizadeh@rmit edu au. "Identifying bird species as biodiversity indicators for terrestrial ecosystem management." RMIT University. Mathematical and Geospatial Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20061116.161912.

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It is widely known that the world is losing biodiversity and primarily it is thought to be caused by anthropogenic activities. Many of these activities have been identified. However, we still lack a clear understanding of the causal relationships between human activities and the pressures they place on the environment and biodiversity. We need to know how ecosystems and individual species respond to changes in human activities and therefore how best to moderate our actions and reduce the rate of loss of biodiversity. One of the ways to detect these changes is to use indicators of ecosystem conditions. Indicators are statistics following changes in a particular factor usually over time. These indicators are used to summarise a complex set of data, and are seen as being representative of the wider situation in that field. So it can be assumed that if that particular factor is declining or improving, then the situation in general is also declining or improving. They are used to check the status and trends of biodiversity by both the public and policy makers. Indicators are also used to assess national performance and can be used to identify the actions required at the policy level. In this manner, they provide an important link between policy-makers and scientists collecting the data. The current thesis investigates the possibility of using bird species as indicators of biodiversity for better management of natural terrestrial ecosystems, by identifying their habitats according to various environmental factors. The study is established by drawing upon three main scientific areas: ecology, geographical information system (GIS), and statistical modelling. The Mornington Peninsula and Western Port Biosphere Reserve (MPWPBR) (Victoria, Australia) was chosen for the study area because of the combination of suburban and natural environments that made it optimum for this type of study. Once the study area was defined, the necessary data for the research were obtained from various sources. Birds Australia provided data on recorded observation of 271 bird species within the study area. Based on the nature of this study, seven species were selected for the study. The criteria for this selection are discussed in Chapter 3. Most literature state that the primary determinant for bird abundance is vegetation and land cover. Because of this, Ecological Vegetation Class (EVC) layer was used to determine which type(s) of vegetation have the greatest impact on habitat selection. Each species showed a relationship to a number of v vegetation types. These EVCs were combined to produce vegetation patches, and were considered as potentially suitable habitats of corresponding bird species. For each of the species, these habitat patches were analysed for the different aspects of patch characteristics (such as the level of patchiness, connectivity, size, shape, weighted distance between patches, etc.) by using the Landscape Context Tool (a GIS add-on). This process assisted the understanding of the importance of patch quality in habitat selection among different bird species by analysing the location of bird observation sites relative to habitat patches. In this way, the association between bird presence and the conditions of a habitat patch was identified by performing a discriminant function analysis. To investigate the probability of a species presence according to different environmental factors, a model of species distribution was created. Binary logistic regression was used to indicate the level of effect of each variable. The model was then successfully validated in the field. To define the indicators of environmental factors, it was essential to separate bird species based on their dependency on one or more of the studied variables. For this purpose, One-Way ANOVA was used. This analysis showed that some bird species can be considered as indicators of urban areas, while others could be good indicators of wellpreserved large forests. Finally, it must be mentioned that the type and quality of the datasets are crucial to this type of study, because some species have a higher degree of sensitivity to certain types of vegetation or land cover. Therefore, the vegetation data must be produced as detailed as possible. At the same time, the species data needs to be collected based on the presence and absence (versus presence-only) of the birds.

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Eisenmenger, Nina, Stefan Giljum, Franz Stephan Lutter, Alexandra Marques, Michaela C. Theurl, Henrique M. Pereira, and Arnold Tukker. "Towards a conceptual framework for social-ecological systems integrating biodiversity and ecosystem services with resource efficiency indicators." MDPI AG, 2016. http://dx.doi.org/10.3390/su8030201.

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In this article we develop a comprehensive conceptual framework for resource efficiency indicators with a consistent link of resource use to the socio-economic system and activities therein as well as to the natural system and its ecosystem functioning. Three broad groups of indicators are defined: (1) resource use indicators representing pressures on the environment; (2) resource efficiency indicators relating resource use indicators to the socio-economic side; and (3) environmental impact indicators linking resource use impacts on the state of the natural system. Based on this conceptual framework we develop a structure for possible resource efficiency indicators and conduct a RACER evaluation on the Relevance, Acceptance, Credibility, Easiness and Robustness of indicators. With the RACER evaluation, we identify areas where indicators are well established and available as well as areas where indicators still need further development or even need to be designed first.

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Kassel, Samantha J. "Selecting species as indicators of ecological integrity a conceptual model based on mammals of Algonquin Provincial Park, Ontario, Canada /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ27357.pdf.

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Lansing, Stephanie Lipe. "Nutrient removal and indicators of self-organization in an ecological treatment system (ETS) for dairy wastewater." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1413372346.

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Lee, Ka-Man. "Impact of Urbanisation on Estuarine Sandflats: Use of Ecological Indicators, Stable Isotope Enrichment and Network Modelling." Thesis, Griffith University, 2011. http://hdl.handle.net/10072/366733.

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Urbanisation often exerts large-scale adverse effects on coastal areas and estuaries, which are ecologically diverse and highly productive habitats. Understanding the ecological resilience of these habitats is a prerequisite for their management. Direct quantification of ecosystem functioning using conventional approaches, however, is difficult and time-consuming. This difficulty has greatly restricted ecosystem-level research and thus, the ability to predict an ecosystem’s responses to urbanisation. The main aim of this thesis was to assess the impact of urbanisation on estuarine sandflats. I developed a novel food web analytical approach, by combining stable isotope (13C) enrichment, compartmental modelling, and ecological network analysis techniques to quantify food web dynamics. This approach was tested with estuarine sandflats, which is one of the most important coastal habitats worldwide. The novel approach allows quantitative testing of specific hypotheses about food web dynamics through manipulative experiments, by comparing system indices that reflect ecosystem condition. Further, I conducted manipulative experiments using this approach to investigate the structural and functional response of a multi-level estuarine sandflat food web to two common anthropogenic stressors from urbanisation, namely, organic enrichment and physical disturbance.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Giffith School of Environment
Science, Environment, Engineering and Technology
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Andersson, Isabell. "Modes of Apprehension, and Indicators thereof, in Visual Discrimination of Relative Mass." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-108214.

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Karnauskas, Mandy M. "From Physics to Fishers: A Multidisciplinary Approach to Evaluating Indicators of Fishery Benefits of Marine Reserves." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/704.

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Marine reserves are promising tools for fisheries management, and are especially suited for complex, multi-species fisheries. Recent work has focused on the design of reserves to achieve particular management objectives and on defining appropriate indicators for monitoring to determine whether these objectives are being met. In principle, there should be a strong correlation between biological, social and economic indicators that are all correlated with fish abundance and ecosystem health. In practice, different indicators are often inconsistent, and it is common for researchers and fishers to have conflicting opinions on how well reserves are meeting management goals. I suggest that these discrepancies are not necessarily due to conflicting opinions regarding management objectives, but rather that the inherent biases in different sampling schemes may cause different measures of the same parameter to be uncorrelated. For example, scientists tend to sample only snapshots in time and space in randomly chosen locations, while fishers sample over much greater temporal and spatial scales but in non-random locations. Furthermore, marine ecosystems are extremely complex, and failing to account for the full extent of this complexity may lead to erroneous measurement of biological trends. The purpose of this dissertation is to determine the causes of discrepancies between different types of indicators using a multidisciplinary approach. A detailed study of the Glover’s Reef Marine Reserve (GRMR) in Belize provides a basis for comparison. Chapters 2 to 4 of the dissertation focus on understanding how the GRMR has functioned to produce fisheries benefits, and elucidating some of the factors responsible for variation in species’ responses to reserve protection. Chapters 5 to 7 of the dissertation focus on comparisons of different indicators of changes in fish abundances, and explain the circumstances under which indicators may disagree. With a better understanding of the functioning of the GRMR based on both scientific and local knowledge, efforts can be made to develop more appropriate indicators, and these indicators can then be tested for use in other coral reef reserves worldwide.

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Gardner, Eric T. "Arthropod and Plant Communities as Indicators of Land Rehabilitation Effectiveness in a Semi-arid Shrub-steppe." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1733.

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We describe a case study evaluating the ecological impact of Bromus tectorum L. (cheatgrass) invasion following fire disturbance and the effectiveness of revegetation in improving ecological integrity in a degraded semi-arid shrub steppe system. The effectiveness of rehabilitation efforts was assessed from measurements of arthropod richness, vegetation and arthropod community composition, and ground cover characteristics in three habitats: undisturbed, burned and weed-infested (B. tectorum), and burned and rehabilitated with native and non-native vegetation. Arthropods were collected in each habitat using pitfall traps. Differences in arthropod richness were compared using rarefaction curves. Non-metric multidimensional scaling, and non-parametric multivariate statistical procedures including analysis of similarity and similarity percentages routines were used to compare arthropod and vegetation community composition and ground cover characteristics between habitats. Arthropod communities in the rehabilitated habitat were distinct from and intermediate to those observed in the undisturbed and weed-infested habitats. Rehabilitation in this instance resulted in an improvement in ecological integrity and perhaps an intermediate step on the way complete restoration. Arthropod richness, arthropod and vegetation community composition, and ground cover characteristics were all useful indicators of ecological integrity, but returned slightly different results. Assessing multiple variables yielded the most complete understanding of the habitats studied.

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Rickert, Corinna [Verfasser]. "Microlepidoptera in salt marshes- Life history, effects of grazing and their suitability as ecological indicators / Corinna Rickert." Kiel : Universitätsbibliothek Kiel, 2010. http://d-nb.info/1030093326/34.

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Lopes, Marta Filipa Lobão. "Ecological quality assessment in transitional systems." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14856.

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Doutoramento em Biologia
Estuaries are poles of attraction for human settlement which is a source of pressures to surface water bodies. The implementation of the European Water Framework Directive (WDF, 2000/60/EC) has increased the investigation in order to develop methodologies to assess the Ecological Quality Status (EQS) of aquatic ecosystems. Transitional systems are naturally stressed and characterized by highly dynamic physical, chemical and hydro-morphologic conditions and by species with a higher level of tolerance to change, being more difficult to develop suitable quality indicators for these systems. The general purpose of this study is to test the ability of synthesis descriptors, including primary (S, taxa richness) and derived biological variable (H’, Shannon-Wiener diversity), biotic indices (AMBI and M-AMBI), body size properties (abundance distribution by body size classes, length, weight and length-weight relationships) and non-taxonomic indices (ISS), as well as functional indicators related to the decomposition rates of various experimental substrates, a macrophyte (Phragmites australis) and an alga (Fucus vesiculosus), to evaluate the environmental quality in transitional systems. This study was carried out in one of the most pristine channels of the Ria the Aveiro, Mira Channel, along a full salinity gradient and in a metals and metalloid sediment contamination area, the Estarreja Channel, and two reference channels (Canelas and Salreu). In this study were used different sampling techniques, the leaf-bag technique and a hand-held corer. In Mira Channel, the alga and the macrophyte presented an opposite trend in the decomposition rate along the salinity gradient, with the decomposition rates of the alga always higher than those of the macrophyte. The decomposition rates of the macrophyte and the alga were higher in the mid estuary and in higher salinity areas, respectively, corresponding to the preferencial distribution areas of each species. The macrobenthic fauna associated with the decaying and an artificial substrate (control) showed equally well the benthic succession from the marine to the freshwater areas and, despite the strong differences in the decay rates, no significant differences were found between the benthic communities associated with the alga and the macrophyte. The body size properties of the macrobenthic fauna associated with the P. australis leaf-bag (1mm and 5mm) and corer samples were studied along the full salinity gradient. The dominant species of the sub-set of measured specimens were not the same of the original macrobenthic fauna sampled but, despite that, the sub-set of measured specimens was also able to show the benthic succession from the marine to the freshwater areas. The body size abundance distribution of the benthic macroinvertebrates according to the ISS size classes did not show a particular trend in any sampler along the salinity gradient. Significant differences were found in the length, weight and length-weight relationships of Annelids, , Molluscs and even some species along the salinity gradient. No significant differences were found in the AMBI, M-AMBI and ISS values along the salinity gradient for all the samplers. The EQS of the corer samples obtained using the M-AMBI was lower than that of the leaf-bags. The EQS obtained with the ISS was higher than that obtained with the M-AMBI in the leaf-bags but not in the corer samples. The ecological effects of contaminated sediments associated with the industrial chemical effluents discharged in the Estarreja Channel were studied a decade after ceasing the emissions, using the Sediment Quality Triad approach and two reference channels. The results showed that despite the emissions ceased in 2004, the sediment remains polluted with high levels of metals and metalloid, available to bioaccumulation and with severe consequences at the community level. The sediment contamination problem was also studied using the leaf-bag technique with a macrophyte, an alga and a control substrate. The results showed that the decay rates, the associated macrofauna and the application of the AMBI, M-AMBI and ISS indices to the mesh-bag samples were not able to identify the sediment contamination. Contrarily to the AMBI, the M-AMBI and the ISS showed significant differences between the contaminated and the reference channels for the corer samples. Although such statistical significance, the interest of using these complex biotic indices could be questioned, when much simple ones, like the S and H’ allow to reach the same conclusions.
Os estuários são pólos de atração para a instalação de aglomerados humanos, constituindo uma fonte de pressão para as massas de água superficiais. Com a implementação da Diretiva Europeia Quadro da Água (DQA, 2000/60/CE) tem aumentado a investigação no sentido de desenvolver metodologias para avaliar o estado de qualidade ecológica (EQE) dos ecossistemas aquáticos. Os sistemas de transição são caracterizados por condições físico-químicas e hidromorfológicas extremamente dinâmicas e por espécies com uma maior tolerância à mudança, sendo difícil desenvolver indicadores de qualidade adequados para estes ecossistemas. O objetivo deste estudo é testar a capacidade de descritores de síntese, tais como a riqueza em espécies (S) e a diversidade de Shannon-Wiener (H'), índices de base taxonómica (AMBI e M-AMBI) e não taxonómica (ISS), as propriedades do tamanho corporal (distribuição de abundância por classes de tamanho corporal, comprimento, peso e relações comprimento-peso), bem como indicadores funcionais (taxas de decomposição de uma macrófita (Phragmites australis) e uma alga (Fucus vesiculosus)), para avaliar a qualidade ambiental dos sistemas de transição. Este estudo foi realizado ao longo de um gradiente completo de salinidade num dos canais com menor impacto antropogénico da Ria de Aveiro, o Canal de Mira, numa área com contaminação sedimentar por metais e metaloides, o Canal de Estarreja, e dois canais de referência (Canelas e Salreu). Neste estudo foram utilizadas diferentes técnicas de amostragem, a técnica dos sacos de folha e corers. No Canal de Mira, a alga e a macrófita apresentaram uma tendência oposta na taxa de decomposição ao longo do gradiente de salinidade, com as taxas de decomposição da alga sempre superiores. As taxas de decomposição da macrófita e da alga foram mais elevadas a meio do estuário e em áreas de maior salinidade, respetivamente, correspondendo às preferenciais áreas de distribuição de cada espécie. A fauna bentónica associada aos substratos orgânicos e a um substrato artificial (controlo) mostrou a sucessão bentónica ao longo do gradiente estuarino e, apesar das grandes diferenças nas taxas de decomposição, não foram encontradas diferenças nas comunidades bentónicas entre ambos os substratos. As propriedades do tamanho corporal da fauna bentónica dos sacos de folhas de P. australis (1mm e 5mm) e corers foram estudadas ao longo do gradiente estuarino. As espécies dominantes do sub-conjunto de espécimes medidos não são as mesmas da fauna bentónica original mas, apesar disso, foram capazes de mostrar a sucessão bentónica ao longo do gradiente salino. A distribuição da abundância pelas classes de tamanho estabelecidas para o cálculo do índice ISS não mostrou nenhuma tendência ao longo do gradiente de salinidade em nenhum dos amostradores. Foram encontradas diferenças significativas no comprimento, peso e na relação comprimento-peso dos Anelídeos, Artrópodes, Moluscos e de algumas espécies ao longo do gradiente de salinidade. Não foram encontradas diferenças significativas nos valores AMBI, M-AMBI e ISS ao longo do gradiente estuarino. O EQE das amostras dos corer foi inferior ao dos sacos de folhas. O EQE obtido com o ISS foi mais elevado do que o obtido com o M-AMBI nos sacos de folha, mas não nas amostras do corer. Os efeitos ecológicos associados à contaminação dos sedimentos por efluentes químicos lançados no Canal de Estarreja foram estudados uma década após a sua cessação, recorrendo à Tríade de Qualidade Sedimentar e dois canais de referência. Os resultados mostraram que o sedimento permanece contaminado com elevados níveis de metais e metaloide, disponíveis para serem bioacumulados e com graves consequências ao nível da comunidade. A contaminação do sedimento foi também estudada utilizando a técnica dos sacos de folhas com a macrófita, a alga e um substrato de controlo, tendo-se verificado que as taxas de decomposição, a macrofauna associada e a aplicação dos índices AMBI, M-AMBI e ISS aos sacos de folhas não foram capazes de identificar o problema. Ao contrário do AMBI, o M-AMBI e o ISS apresentaram diferenças significativas entre o canal contaminado e os canais de referência para as amostras do corer. No entanto, a utilização de índices tão complexos é questionável, na medida em que índices mais simples, tais como a S e a H', permitem chegar às mesmas conclusões.

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Górka, Katarzyna. "Dental morphology and dental wear as ecological and alimentary indicators: sexual and intergroup variation in traditional human populations." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/384843.

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Sexual division of labour involving the use of teeth in non-masticatory activities in the Tigara population form Point Hope did not affect the wear of the upper and lower first molars and, therefore, food chewing was the main factor causing dental wear in this population. No sexual differences were found in the percentage of dentine exposure of the first molars, which is indicative that both sexes in the Tigara populations consumed very similar diets despite sex differences in the dental wear on the anterior dentition have been reported. The percentage of dentine exposure was positively correlated with the age group categories of the individual in the Tigara population, proving that dental wear is a cumulative process throughout lifespan. Crown relief of the first molars was negatively correlated with the percentage of dentine exposure, which shows that dental wear causes a decrease in cusp and crown heights. Crown relief is a continuous variable significantly correlated with age at death. Crown complexity, on the other hand, was greater in teeth with high levels of dentine exposure, showing that wear facets significantly contribute to food processing during mastication. No significant correlations were found between the percentage of dentine exposure and the density and average length of buccal scratches. However, a trend towards shorter scratches on buccal enamel surfaces was observed with decreasing values of crown relief, which demonstrates that the progressive accumulation of buccal scratches caused by enamel abrasion, which results in a reduction of their average length, is a parallel process with respect to the reduction of crown height. No significant differences on dentine exposure by sex were observed in any of the traditional modern human populations studied, which might be indicative that dental wear on molar teeth is not an adequate measure of the impact of sexual division of labour on the diet of both sexes. No significant differences in dental wear was found between the hunter-gatherer and agro-pastoral groups, despite they had very distinct diets and cultural practices in relation to food acquisition and processing. Such lack of significant wear differences among populations could be indicative that different diets may result in similar wear patterns and that the physical properties of chewed food particles might be more informative on dental wear processes than discrete classifications of dietary habits. First upper molar shape differences from all the modern human populations studied reflected the patterns of human migration and dispersal, although retaining a significant phylogenetic signal. The shape of the upper first molar in the Hutu population may be considered ancestral to the other groups compared that show a derived conditions consisting in more quadrangular and less oval shaped molars. Molar shape variability clearly discriminated the Sundadont and Sinodont populations. The Sinodont upper first molar would be characterized by more regular, rounded outlines, whereas the Sundadont would show more oval and irregular crown shapes.
Los dientes constituyen un material de estudio multidisciplinar y son usados en varias áreas de la ciencia: odontología, anatomía comparativa, paleontología, paleoantropología, genética y ciencias forenses, entre otras. La presente tesis tiene como objetivo principal investigar la variabilidad dental en populaciones de humanos modernos desde una perspectiva multi-metodológica. El enfoque principal fue el desgaste dental, aunque también se analizaron otras características, como la variabilidad métrica, la forma dental, el microdesgaste, el relieve o la complejidad de la corona. Objetivos: Valorar si la división sexual del trabajo presente en los esquimales de Point Hope puede afectar al desgaste del primer molar; Analizar las correlaciones entre marcadores del macrodesgaste, microdesgaste, relieve y complejidad de la corona dental para explorar las diferentes líneas de estudio de la pérdida del esmalte y sus correlaciones; Investigar la posible influencia de la división sexual del trabajo sobre la dienta en diferentes poblaciones de cazadores-recolectores y agricultores; Analizar la forma de los primeros molares en varios grupos de poblaciones humanas modernas mediante la innovadora técnica de la morfología geométrica tridimensional. La investigación ha sido realizada únicamente con el material disponible en las colecciones dentales de la Universidad de Barcelona y la Universidad de Alicante. Se analizaron 251 primeros molares procedentes de 188 individuos de 9 poblaciones diferentes de humanas modernas (Agta, Aborígenes Australianos, Batéké-Balali, Esquimo, Hutu, Javaneses, Khoe, Navajo y San). Al examinar las posibles influencias de la división sexual del trabajo en la dieta en otras poblaciones de economía tradicional, no se ha encontrado tampoco diferencias significativas entre hombres y mujeres en ningún de los grupos analizados. Tampoco se han encontrado variaciones en el desgaste entre los patrones de subsistencia cazador-recolector y agricultor. El estudio de la forma dental muestra una importante variación de la forma del primer molar superior entre los grupos.

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Jacobs, Francois Jakob. "The behavioural ecology of the Orange-Vaal River yellowfish in lentic and lotic ecosystems, North-West Province, South Africa / Francois Jakob Jacobs." Thesis, North-West University, 2013. http://hdl.handle.net/10394/9514.

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Fishes are widely used by biologist as ecological indicators that measure key elements of complex systems, without having to capture the full complexity of a specific system. The Vaal River in South Africa is classified as Africa’s hardest working river and is home to, two yellowfish species that are socially and economically important. Both these yellowfish species are considered to be sensitive to changes in water quantity and quality, habitat destruction and utilisation pressure and are often used as ecological indicators to manage aquatic ecosystems. Very little however, is known about their movement, response to changing environmental variables and interspecies habitat preferences. This study therefore aims to use radio telemetry as a method to characterise and evaluate how yellowfish behaviour is influenced by changing environmental variables. To characterise the behavioural ecology of the Vaal-Orange River yellowfish species in lentic and lotic ecosystems, Labeobarbus aeneus (n=18) and L. kimberleyensis (n=3) were fitted with externally attached radio transmitters in Boskop Dam (L. aeneus, n=4) and the Vaal River (L. aeneus, n=14) (L. kimberleyensis, n=3). Various methods were used to collect yellowfish species including: gill nets, to target mobile individuals, in deep habitats, electro-fishing (electro-narcosis) to collect yellowfish in shallow habitats and angling techniques in a wide variety of habitats. Thereafter yellowfish species were sedated and tagged with externally attached radio transmitters, before being released back into the system. Yellowfish were monitored for eleven months using a remote monitoring system together with manual monitoring surveys. Analyses of data collected showed that L. aeneus follows distinct behavioural patterns, with some individual variations in behaviour. Labeobarbus aeneus exhibited higher movement that are associated with deeper water during daylight hours (04:00-16:00). During nocturnal periods (20:00-04:00) L. aeneus showed a decrease in movement activity and preferred shallower water compared to daytime. However, L. aeneus in the Vaal River seems to be less influenced by bright daylight and this might be due to the turbidity of the river water. Labeobarbus aeneus in Boskop Dam showed higher movement counts during full moon phases whereas L. aeneus in the Vaal River showed higher movement counts during new moon phases. All tagged fishes in Boskop Dam and in the Vaal River preferred deeper water during full moon phases than during new moon phases. Movement were significantly higher (P<0.05) with increased temperatures and shallower water in summer whereas movement significantly decreased (P<0.05) with a decrease in temperature and increased depth in autumn and winter. Seasonal movement data were, however, limited. This study confirms that radio telemetry methods can be used to characterise the behavioural ecology of yellowfish species. In addition, the study has improved the knowledge of how environmental variables may affect the behaviour of yellowfish species. However, due to limited data and our understanding of these species, it is still uncertain how behaviour of yellowfish species can be applied as an ecological indicator of aquatic ecosystems.
Thesis (MSc (Zoology))--North-West University, Potchefstroom Campus, 2013

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35

Angelstam, Per, Jean-Michel Roberge, Robert Axelsson, Marine Elbakidze, Karl-Olof Bergman, Anders Dahlberg, Erik Degerman, et al. "Evidence-Based Knowledge Versus Negotiated Indicators for Assessment of Ecological Sustainability : The Swedish Forest Stewardship Council Standard as a Case Study." Linköpings universitet, Biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-90236.

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Assessing ecological sustainability involves monitoring of indicators and comparison of their states with performance targets that are deemed sustainable. First, a normative model was developed centered on evidence-based knowledge about (a) forest composition, structure, and function at multiple scales, and (b) performance targets derived by quantifying the habitat amount in naturally dynamic forests, and as required for presence of populations of specialized focal species. Second, we compared the Forest Stewardship Council (FSC) certification standards’ ecological indicators from 1998 and 2010 in Sweden to the normative model using a Specific, Measurable, Accurate, Realistic, and Timebound (SMART) indicator approach. Indicator variables and targets for riparian and aquatic ecosystems were clearly under-represented compared to terrestrial ones. FSC’s ecological indicators expanded over time from composition and structure towards function, and from finer to coarser spatial scales. However, SMART indicators were few. Moreover, they poorly reflected quantitative evidence-based knowledge, a consequence of the fact that forest certification mirrors the outcome of a complex social negotiation process.

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Górka, Katarzyna. "Dental morphology and dental wear as dietary and ecological indicators: sexual and inter-group differences in traditional human populations." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/384843.

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Sexual division of labour involving the use of teeth in non-masticatory activities in the Tigara population form Point Hope did not affect the wear of the upper and lower first molars and, therefore, food chewing was the main factor causing dental wear in this population. No sexual differences were found in the percentage of dentine exposure of the first molars, which is indicative that both sexes in the Tigara populations consumed very similar diets despite sex differences in the dental wear on the anterior dentition have been reported. The percentage of dentine exposure was positively correlated with the age group categories of the individual in the Tigara population, proving that dental wear is a cumulative process throughout lifespan. Crown relief of the first molars was negatively correlated with the percentage of dentine exposure, which shows that dental wear causes a decrease in cusp and crown heights. Crown relief is a continuous variable significantly correlated with age at death. Crown complexity, on the other hand, was greater in teeth with high levels of dentine exposure, showing that wear facets significantly contribute to food processing during mastication. No significant correlations were found between the percentage of dentine exposure and the density and average length of buccal scratches. However, a trend towards shorter scratches on buccal enamel surfaces was observed with decreasing values of crown relief, which demonstrates that the progressive accumulation of buccal scratches caused by enamel abrasion, which results in a reduction of their average length, is a parallel process with respect to the reduction of crown height. No significant differences on dentine exposure by sex were observed in any of the traditional modern human populations studied, which might be indicative that dental wear on molar teeth is not an adequate measure of the impact of sexual division of labour on the diet of both sexes. No significant differences in dental wear was found between the hunter-gatherer and agro-pastoral groups, despite they had very distinct diets and cultural practices in relation to food acquisition and processing. Such lack of significant wear differences among populations could be indicative that different diets may result in similar wear patterns and that the physical properties of chewed food particles might be more informative on dental wear processes than discrete classifications of dietary habits. First upper molar shape differences from all the modern human populations studied reflected the patterns of human migration and dispersal, although retaining a significant phylogenetic signal. The shape of the upper first molar in the Hutu population may be considered ancestral to the other groups compared that show a derived conditions consisting in more quadrangular and less oval shaped molars. Molar shape variability clearly discriminated the Sundadont and Sinodont populations. The Sinodont upper first molar would be characterized by more regular, rounded outlines, whereas the Sundadont would show more oval and irregular crown shapes.
Los dientes constituyen un material de estudio multidisciplinar y son usados en varias áreas de la ciencia: odontología, anatomía comparativa, paleontología, paleoantropología, genética y ciencias forenses, entre otras. La presente tesis tiene como objetivo principal investigar la variabilidad dental en populaciones de humanos modernos desde una perspectiva multi-metodológica. El enfoque principal fue el desgaste dental, aunque también se analizaron otras características, como la variabilidad métrica, la forma dental, el microdesgaste, el relieve o la complejidad de la corona. Objetivos: Valorar si la división sexual del trabajo presente en los esquimales de Point Hope puede afectar al desgaste del primer molar; Analizar las correlaciones entre marcadores del macrodesgaste, microdesgaste, relieve y complejidad de la corona dental para explorar las diferentes líneas de estudio de la pérdida del esmalte y sus correlaciones; Investigar la posible influencia de la división sexual del trabajo sobre la dienta en diferentes poblaciones de cazadores-recolectores y agricultores; Analizar la forma de los primeros molares en varios grupos de poblaciones humanas modernas mediante la innovadora técnica de la morfología geométrica tridimensional. La investigación ha sido realizada únicamente con el material disponible en las colecciones dentales de la Universidad de Barcelona y la Universidad de Alicante. Se analizaron 251 primeros molares procedentes de 188 individuos de 9 poblaciones diferentes de humanas modernas (Agta, Aborígenes Australianos, Batéké-Balali, Esquimo, Hutu, Javaneses, Khoe, Navajo y San). Al examinar las posibles influencias de la división sexual del trabajo en la dieta en otras poblaciones de economía tradicional, no se ha encontrado tampoco diferencias significativas entre hombres y mujeres en ningún de los grupos analizados. Tampoco se han encontrado variaciones en el desgaste entre los patrones de subsistencia cazador-recolector y agricultor. El estudio de la forma dental muestra una importante variación de la forma del primer molar superior entre los grupos.

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Gonzalez, Carla Sofia Dávila Soares. "Interpreting change in human-nature and long term social relationships." Doctoral thesis, FCT - UNL, 2010. http://hdl.handle.net/10362/5877.

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Dissertação apresentada para obtenção do Grau de Doutor em Ciências do Ambiente, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia.
A conservação da biodiversidade, o desenvolvimento e a ciência modernos tiveram um impacto profundo nos sistemas humanos e naturais acoplados e na sua gestão. Os desafios que hoje se colocam a este nível em regiões moldadas no longo prazo pela presença humana, como é o caso do Mediterrâneo, são exemplo evidente das limitações criadas pela dicotomização entre economia e ecologia, humanos e natureza, conhecimento leigo e científico, práticas institucionais formais e locais informais e perspectivas tecnocráticas ou sociais; resultantes daquelas tendências. O presente trabalho foi ancorado num tema de estudo que evidencia tais tensões: o processo de implementação da Rede Natura 2000, que se dedica à conservação da biodiversidade na Europa e ao mesmo tempo prioriza a consideração de características rurais culturais e socioeconómicas. Neste contexto, desenvolveu-se um estudo de caso sobre as Ribeiras Mediterrânicas de Monfurado (RMM), que vão de encontro a esta descrição. Foram articuladas diferentes tradições científicas e tipos de conhecimento de modo a testar a hipótese de que desta forma seria possível: i) compreender os agregados humano-natureza existentes nas RMM e contribuir para a sua gestão; ii) compreender as relações sociais no longo prazo, especificamente a nível da conexão entre diferentes grupos de actores sociais ligados às RMM, caracterizando o seu diálogo. Desta forma, foi proposto e aplicado um enquadramento transdisciplinar orientado para a prática e inspirado nos pensamentos coevolutivo e de investigação-acção utópica crítica. Para analisar as RMM, foram combinadas metodologias das ciências naturais e sociais, que variam desde biomonitorização à aplicação de um índice de integridade biótica, à análise interpretativa de entrevistas e à revisão histórica. A caracterização das ribeiras e da relação humano-natureza nelas existente contribuiu ao nível da gestão e da compreensão dos sistemas sócio-ecológicos das RMM. A importância da herança histórica de características sociais no longo prazo (como se mostrou ser o caso da desigualdade social) e de episódios históricos políticos específicos para as relações sociais actuais, e consequentemente para os programas de conservação, foi ainda assinalada. Os resultados também permitiram explorar e fundar perspectivas de melhoria futura do diálogo entre grupos sociais e da gestão de recursos naturais, adoptando-se uma postura de abertura perante a mudança sócio-ecológica e considerando-se o caso de estudo ‘inacabado’. Os resultados obtidos permitiram verificar ainda a possibilidade de reduzir as fronteiras entre sectores disciplinares, tipos de conhecimento e na conceptualização da divisão ontológica humano-natureza; cuja combinação, como se ilustra, pode contribuir para a gestão de recursos naturais e, mais importante, pode potenciar conhecimento e experiências acumuladas. Finalmente, colocou-se o caso de estudo nos contextos global e de longo prazo, ampliando o significado das relações humano-natureza e sociais tratadas; e gerando uma discussão sobre paradigmas de desenvolvimento e sistema mundial, sobre mudança e sua relação com utopia e experiências biográficas, sobre o potencial coevolutivo, sobre os significados de natureza e sobre a significância da capacidade humana de aspirar, pensar e agir.

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Pham, Vivian G. "Ecological Risk Assessment of Heavy Metal Content in the Hatillo River, Costa Rica." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/571.

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Rivers all around the world have become increasingly polluted with heavy metals, largely due to industrialization and urbanization. Organisms exposed to high concentrations of heavy metals have shown evidence of biotoxicity and physical deformities. With biomagnification in mind, the possibility that this contamination may soon directly affect humans is a real concern, and policies in manufacturing industries worldwide may have to be reformed. In this study, we measured the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb) in the Hatillo River and compared these values to those measured in the Tarcoles River, a highly polluted river, and Terciopelo Creek, a relatively clean river. The results showed that the Hatillo River had significantly lower levels of most detected heavy metals than both the Tarcoles and Terciopelo. Overall, sediments in all rivers showed high levels of heavy metal content--especially in chromium, copper, nickel, and lead--which could build up and affect organisms over a long period of time.

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39

Bezombes, Lucie. "Développement d'un cadre méthodologique pour l'évaluation de l'équivalence écologique : Application dans le contexte de la séquence "Éviter, Réduire, Compenser" en France." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAS044/document.

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Face à l’érosion mondiale de la biodiversité causée par les activités humaines, la compensation écologique, et plus largement la séquence « Eviter Réduire Compenser » (ERC), s’est développée depuis les années 1970, avec l’ambition de concilier développement au niveau des projets d’aménagement et préservation de la biodiversité. L’objectif de cette séquence est d’atteindre « zéro perte nette » (No net Loss, NNL) de biodiversité. Un des enjeux clé pour y arriver consiste à démontrer l’équivalence écologique entre les gains apportés par la compensation et les pertes occasionnées par les impacts. Malgré les avancées règlementaires, le cadre français n’inclut pas de méthode à suivre pour déterminer l’équivalence et aucune n’est unanimement reconnue. Cela amène à des pratiques hétérogènes et une difficulté d’atteindre le NNL. Dans ce contexte, ces travaux de thèse visent à développer un cadre méthodologique standardisé (CMS) d’évaluation de l’équivalence, combinant à la fois opérationnalité, bases scientifiques et exhaustivité (prise en compte des quatre dimensions de l’équivalence : écologique, spatiale, temporelle et les incertitudes). Dans un premier temps, 13 méthodes utilisées à l’étranger sont analysées afin d’identifier des éléments structurant pour le développement du CMS adapté au contexte français. La construction du CMS est décomposée en trois étapes. La première consiste à sélectionner un lot organisé d’indicateurs sur lesquels baser l’évaluation de l’équivalence, permettant de répondre aux exigences règlementaires et reflétant la complexité de la biodiversité : évaluation à deux échelles spatiales (sur le site et dans un périmètre élargi) et à trois niveaux d’enjeu (général, habitat ou espèce). La deuxième étape porte sur la prédiction de l’évolution dans le temps des valeurs initiales des indicateurs, sous l’effet des impacts et de la compensation, en prenant en compte les incertitudes associées. La troisième étape conduit à la détermination de règles de calcul des pertes et des gains aboutissant à l’évaluation globale de l’équivalence. Le CMS ainsi construit est ensuite testé sur deux sites d’étude afin d’en démontrer la plus-value et d’en éprouver les limites. Des perspectives d’amélioration du CMS, et plus largement de l’évaluation de l’équivalence sont dégagées. En dernier lieu, l’ensemble de ces éléments nous permettent de questionner l’efficacité de la compensation écologique pour lutter contre l’érosion de la biodiversité
In light of the global erosion of biodiversity caused by human activities, biodiversity offsets and, more broadly the Mitigation Hierarchy, are increasingly used since the 1970s, with the ambition of reconciling economic development and biodiversity conservation. Its objective is to achieve "No Net Loss" (NNL) of biodiversity. One of the key issues to achieve this goal is to demonstrate ecological equivalence between the gains from offsets and the losses caused by impacts. Despite regulatory improvements, the French law does not include a method for assessing equivalence, and no method is unanimously recognized. This leads to heterogeneous practices and difficulties in reaching the NNL objective. In this context, this thesis aims to develop a standardized methodological framework (SMF) for assessing equivalence, which combines operationality, scientific basis and comprehensiveness (taking into account the four dimensions of equivalence: ecological, spatial, temporal and uncertainties). First, 13 methods used abroad are analysed in order to identify structural elements for the development of a SMF adapted to the French context. The construction is decomposed into three steps. The first consists in selecting an organized set of indicators, on which equivalence assessment should be based in order to meet legislative requirements and reflect the complexity of biodiversity. The assessment is to be done at two spatial scales (on-site and within an expanded perimeter) and at three levels reflecting general or specific issues (habitat or species). The second step regards the prediction of the values of the indicators over time, consequently to the impacts and offsets, taking into account the implied uncertainties. The third step leads us to establish rules for calculating losses and gains, as well as for the overall assessment of equivalence. Finally, this SMF is tested on two study sites in order to demonstrate the added value and to identify its limits. Prospects for improving the SMF, and more broadly the evaluation of equivalence, are then suggested. Finally, all these elements make it possible to question the effectiveness of offsets in order to tackle biodiversity erosion

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Foster, Susan Ann. "Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/2383.

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The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops.

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ASANTE, MELDOMI ASABEA. "EFFECT OF URBAN RIPARIAN DEVELOPMENT ON BIODIVERSITY; USING BIRDS AND VEGETATION AS ECOLOGICAL INDICATORS IN COOPER CREEK LOCATED IN SOUTHWEST OHIO." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1146157392.

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42

Coley, Alex, Jordan Jerkovich, and Madsen Mikkel Pilgaard. "Pursuing Sustainability and Prosperity in Swedish Municipalities: Using Indicators to Inform Strategic Governance." Thesis, Blekinge Tekniska Högskola, Institutionen för strategisk hållbar utveckling, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-18350.

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Deciding between sustainability or prosperity may be a false choice when the phenomena are appropriately defined and considered together (Stiglitz et al. 2009). With reference to existing indicator systems and frameworks, including the Framework for Strategic Sustainable Development (FSSD) and the Community Capitals Framework (CCF), this research developed three novel indices (SMSI, SMSI+, and CCFI) using a Strategic Sustainable Development (SSD) approach to measure and analyze the correlation between sustainability (SMSI, SMSI+) and prosperity (CCFI) in Swedish municipalities. The spearman rank-order coefficient values were 0.259 and 0.588 for SMSI and CFFI and SMSI+ and CCFI, respectively. Both were significantly correlated with a p-value of 0.05, where SMSI+ and CCFI were 0.329 more correlated than SMSI and CCFI. This showed that an index that more comprehensively considers an SSD approach correlates more with CCFI. Furthermore, only six out of 234 Swedish municipalities ranked in the top 10 percent of both SMSI+ and CCFI, showing that it is difficult to successfully pursue sustainability and prosperity together in practice. Importantly, this research also demonstrates that it is possible to create indices using an SSD approach while outlining the methods for how to do so.

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Вишницька, Олена Іванівна, Елена Ивановна Вишницкая, and Olena Ivanivna Vyshnytska. "Формування регіональних та локальних еколого-економічних показників інвестицій екологічного спрямування." Thesis, Видавництво СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/3854.

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В роботі висвітлюється питання формування еколого-економічних показників інвестицій екологічного спрямування на регіональному та локальному рівнях. Описані етапи визначення інвестиційної привабливості видів економічної діяльності на рівні регіону. Визначені показники комплексної еколого-економічнї оцінки інвестиційних проектів. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/3854
This article highlights the issue of creating environmental and economic indicators of environmental investments on regional and local levels. We describe the stage of defining the investment attractiveness of economic activities at the regional level. The indexes of complex ecological-economic evaluation of investment projects were determined. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/3854

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Shaw, Althoff Peggy S. "Indicators of disturbance and recovery of a tallgrass prairie ecosystem following military vehicle traffic." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/460.

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Coulston, John Wesley Riitters Kurt Smith Gretchen Cole. "Large-scale analysis of sustainable forest management indicators assessments of air pollution, forest disturbance, and biodiviersity [sic] /." Connect to this title online, 2004. http://www.lib.ncsu.edu/theses/available/etd-03282004-103433/.

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Wattrus, Jane M. (Jane Marie). "Habitat Evaluation Procedures at Ray Roberts Lake: an Analysis of the Relationship with Ecological Indicators and a Study of Observer and Temporal Variability." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc501233/.

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Habitat Evaluation Procedure data gathered at Ray Roberts Lake in 1989 and 1990 were analysed for temporal variability, observer variability and relationships between Habitat Units (HUs) and species density/diversity. observer variability within a group was analysed by cluster analysis and bootstrapping. Five out of 36 sites showed significant differences in Habitat Suitability Index (HSI) values within the group. A nonparametric Mann-Whitney test was used to analyze temporal variability. One of 6 sites showed a significant difference in HSI values between years. Using Spearman's Rank Correlation Coefficient, a correlation was found between indicator species density and HUs. No significant correlation was indicated between species diversity and HUs.

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Rocco, Bianca Campedelli Moreira. "Avaliação ecológica e da percepção de proprietários rurais do processo de restauração de matas ciliares em Jaú e Saltinho - SP." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-21062013-160950/.

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O Estado de São Paulo passou por um longo processo de degradação e fragmentação, fruto de um modelo de desenvolvimento que baseou sua ampliação agrícola e urbana na derrubada de ecossistemas florestais nativos. A necessidade de aumento na cobertura florestal do estado é reconhecida há muito tempo, principalmente em razão da relação intrínseca entre água e matas, especialmente no caso das matas ciliares. Essa questão gerou ao logo dos anos o aprimoramento do conhecimento técnico na área de restauração, mas este avanço não foi acompanhado de reflexões a respeito de questões sociais, econômicas e políticas. As diversas políticas públicas e instrumentos agrícolas e florestais vigentes não trazem em seu escopo a preocupação com a realidade socioeconômica ou com o desenvolvimento rural. O presente trabalho procurou analisar, através do estudo de caso em duas microbacias hidrográficas do estado de São Paulo, Ribeirão Campestre no município de Saltinho e Córrego Santo Antônio em Jaú, o desenvolvimento áreas de mata ciliar implantadas por quatro instrumentos e políticas públicas de restauração ecológica de matas ciliares em pequenas e médias propriedades. Buscou-se compreender o contexto em que os diferentes instrumentos e políticas de restauração de matas ciliares ocorreram procurando correlacionar indicadores ecológicos de desenvolvimento de áreas de mata ciliar em restauração, com a percepção e o envolvimento dos proprietários rurais nos diversos processos de restauração de matas ciliares estudados. Desta maneira, a partir dos resultados, foi possível demonstrar que conhecer o perfil e a percepção dos proprietários rurais envolvidos em políticas públicas de restauração de matas ciliares é essencial para a para produção de conhecimentos relacionados à restauração de matas ciliares e de políticas públicas relacionadas.
The State of São Paulo has gone through a long process of deterioration and fragmentation, due to the model of development of agricultural and urban expansion based on the destruction of native forest ecosystem. The need to increase the forest covering in the state has been clear for quite some time, especially due to the intrinsic relationship between water and forests, most notably in riparian forests. With time, this issue gave rise to the refinement of technical knowledge in the area of restoration. However, this progress was not accompanied by discussions on social, economic and political issues. The various public policies, laws and regulations in the agricultural and forest area now in place fail to express any concern with socioeconomic reality or with rural development. This text represents an attempt to analyze a case study in two micro-river basins in the State of São Paulo, Brazil, namely, Ribeirão Campestre, in the municipality of Saltinho and Córrego Santo Antônio, in the municipality of Jaú. Specifically, the development of riparian forest areas implemented by four legal instruments and public policies of ecological restoration of riparian forests in small and medium-sized landholdings were investigated. Searched was made to understand the context in which different legal instruments and policies for restoring riparian forests occurred, and ecological indicators of the development of riparian forest areas in restoration were correlated with the perception and involvement of rural landowners in several different processes of restoration of riparian forests. Thus, based on the results, it was possible to demonstrate that understand the profile and perception of landowners involved in riparian forests restoration public policy is essential to the production of knowledge related to riparian forests restoration of and related public policies.

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Mazzei, Viviana. "Diatoms as tools for inferring changing environmental gradients in coastal, freshwater wetlands threatened by saltwater intrusion." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3716.

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Saltwater intrusion alters the natural salinity and phosphorus (P) gradients in the oligotrophic, freshwater wetlands located near coastlines of the Caribbean Basin with important consequences to the structure and function of key ecosystem components, including plants, soil microbes, and periphyton. Periphyton communities, particularly diatoms, are extremely sensitive to water quality changes and can serve as excellent bioindicators; however, little is known about their use in detecting novel rates of saltwater intrusion into coastal, freshwater wetlands. I examined the individual and combined effects of elevated salinity and P on periphyton functional processes and diatom composition by conducting transect surveys along salinity and P gradients in the southern Everglades, as well as through mesocosm studies in which salinity and P were experimental manipulated. I demonstrated that conductivity (a proxy for salinity) and P gradients drive spatial patterns in diatom assemblage structure in the southern Everglades and that these assemblages have relatively low conductivity (2 mS cm-1) and total P thresholds (82 µg g-1). These findings were supported by the experimental work which showed that monthly pulses of elevated salinity only ~1 ppt above ambient was sufficient to cause significant shifts in periphytic diatom assemblages along with reduced periphyton productivity, total carbon, and nutrient content. The addition of P to freshwater and salt-treated periphyton significantly elevated mat total P, underscoring the P-uptake efficiency of periphyton. Surprisingly, addition of P to freshwater periphyton did not elicit significant functional or compositional responses, although chlorophyll-aconcentrations and accumulation rates tended to be higher with P. Similar chlorophyll-atrends were observed for salt-treated mats with added P, but these mats also exhibited significantly higher gross primary productivity and net ecosystem productivity compared to all other treatments and a diatom assemblage distinct from any other treatment. This research provides new and valuable information regarding periphyton dynamics in response to changing water sources that will allow us to extend the use of periphyton, and their diatom assemblages, as tools for environmental assessments related to saltwater intrusion in the southern Everglades and other karstic, freshwater wetlands.

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Kerninon, Fanny. "Développement d'outils méthodologiques pour le suivi et l'évaluation de l'état de santé des herbiers d'outre-mer français et de leur environnement, dans un contexte de pertubations multiples." Thesis, Brest, 2020. http://www.theses.fr/2020BRES0030.

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Les herbiers marins constituent des habitats remarquables et diversifiés des eaux côtières des territoires ultramarins français. Une meilleure compréhension de leur état écologique sous l’influence des perturbations multiples auxquels ils sont soumis est nécessaire pour répondre aux enjeux des politiques publiques environnementales s’appliquant à l’échelle de ces territoires. Divers paramètres représentant la plupart des compartiments biologiques, allant de la physiologie des phanérogames marines à l’écosystème ont été testés in situ dans des conditions environnementales contrastées. Ces expérimentations ont permis d’évaluer les relations pressions-état des herbiers de différents territoires dans les trois océans et de sélectionner les descripteurs les plus pertinents selon les principaux objectifs de gestion. Sur la base des données collectées, une première version d’indicateurs intégrés combinant des indicateurs d'alerte précoce et de diagnostic (nutriments et certains métaux traces) et des paramètres de réponse à long terme (densité des plants et recouvrement) adaptés aux échelles de temps de la gestion ont été développés. Une première classification de l’état des herbiers étudiés est ainsi proposée. Ces outils intégrés devraient permettre de renforcer l’efficacité des mesures de gestion, tout en facilitant une mise en oeuvre mutualisée des différentes politiques publiques. L'évaluation de l'état de santé des herbiers marins et de leur environnement est essentielle afin de déployer des mesures de gestion et de préservation appropriées pour améliorer de manière durable l’état et la résilience de cet écosystème menacé
Seagrass meadows forms remarkable and diversified habitats in the coastal waters of the French overseas territories. A better understanding of their ecological status under multiple disturbances to which they are subjected is necessary to respond to environmental public policy issues applying to these territories. In situ experiments were conducted on the three oceans, in which parameters representing most biological compartments, ranging from the physiology of seagrass to the ecosystem, were tested under contrasting environmental conditions. These experiments lead to assess the pressure-state relationships of seagrass beds in different territories and to select the most relevant descriptors according to the main management objectives. On the basis of the data collected, the first databases of integrated indicators combining early warning indicators (nutrients and trace metals) and long-term response parameters (plant density and cover) adapted to management time scales were developed. A first classification the health status of studied seagrass meadows is thus proposed. These integrated tools will make it possible to improve the effectiveness of the management of this threatened ecosystem, while facilitating the sharing of the implementation of the various public policies. The assessment of seagrass beds health status and their associated environment is essential to deployed appropriate management actions and improve ecosystem quality and long term resilience

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Altivo, Felipe de Souza. "Avaliação da funcionalidade ecológica de uma área em processo de restauração no bioma da Mata Atlântica, Rio de Janeiro." Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/8354.

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The restoration should involve the return of vegetation cover and ecological processes. This study aims to assess whether the restoration of diversity also promoted the recovery of the ecological functionality of an area located in the Atlantic Forest, in Rio de Janeiro. During the study, a set of ecological functionality of indicators based on community diversity, its structure and its context in the landscape were analized. The most efficient indicators for evaluation of the areas were the structure (density, height and basal area), followed by diversity and evenness (H 'and J). Between the 5th and 20th month, there was a significant reduction of diversity, further for families than for the species. However, indicators of ecological functions did not change between the ages despite the reduction in diversity, showing that there was redundancy of functions between different species. The results suggest the deployment of fewer species maintaining the proportion of the functional diversity of species can optimize the actions of forest restoration for promoting the reduction of mortality, therefore generating greater increase in community structure. The regenerating analysis showed the importance of faunal interactions in forest restoration activities, since 77% of regenerating species found in the area have zoochorous dispersion syndrome.
A restauração deve envolver o retorno da cobertura de vegetação e dos processos ecológicos. O presente trabalho visa avaliar se a restauração da diversidade também promoveu a recuperação da funcionalidade ecológica em uma área situada no bioma Mata Atlântica, no Rio de Janeiro. Durante o estudo foi analisado um conjunto de indicadores de funcionalidade ecológica baseados na diversidade da comunidade, sua estrutura e seu contexto na paisagem. Os indicadores mais eficientes para avaliação das áreas foram os de estrutura (densidade, altura e área basal), seguidos dos de diversidade e equitabilidade (H´ e J). Entre 5 e 20 meses de idade, houve redução significativa da diversidade, sendo maior para famílias do que para as espécies. Contudo, os indicadores de funções ecológicas não variaram entre as idades apesar da redução na diversidade, mostrando que houve redundância de funções entre diferentes espécies. A análise dos resultados permite sugerir que a implantação de menor número de espécies mantendo-se a proporção da diversidade funcional das espécies, pode otimizar as ações de restauração florestal por promover a diminuição da mortalidade, consequentemente podendo gerar maior incremento em estrutura da comunidade. A análise de regenerantes evidenciou a importância das interações faunísticas nas ações de restauração florestal, já que 77% das espécies regenerantes encontradas na área possuem síndrome de dispersão zoocórica.

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Dissertations / Theses on the topic 'Ecological indicators'

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