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1
Call, Erynn. "River birds as indicators of change in riverine ecosystems." Thesis, The University of Maine, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3663177.
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<p> River-associated birds may be valuable indicators of environmental change in riverine ecosystems because they are predators of fishes and therefore often top predators in the aquatic food web. To evaluate the likely scope of one form of change - river restoration through dam removal and the expected return of abundant diadromous fish prey - we: 1) developed an appropriate river bird survey protocol; 2) documented the relative importance of sea-run fish in the diet of four river bird species, bald eagle (<i>Haliaeetus leucocephalus</i>), osprey (<i>Pandion haliaetus</i>), belted kingfisher (<i>Megaceryle alcyon</i>), and tree swallow (<i> Tachycineta bicolor</i>); 3) documented nest distribution and brood size of osprey; and 4) investigated the relationships between river bird abundance and various habitat parameters. We expect these measures will reflect changes to the river system post-dam removal as diadromous fish populations recover, proliferate, and integrate into the food web. Based on species accumulation curves and first-order Jacknifes, we concluded that biweekly or triweekly I5 minute surveys are sufficient to meet our objectives. Within the Penobscot River, stable isotope analysis of river bird diets indicated that marine nutrients are consumed by bald eagle, osprey, and belted kingfishers that reside below the lowermost dam, but not tree swallows. Despite greater connectivity for and abundance of spawning diadromous fishes (particularly river herring), in the Kennebec and Sebasticook Rivers as compare to the Penobscot River, osprey brood size was not significantly larger. We suspect other factors such as competition with bald eagles may be limiting the benefit of large river herring runs to nesting osprey. Finally, an ordination of 26 river bird species and 5 single-species (invertivore - spotted sandpiper, piscivore - osprey; piscivore - bald eagle; insectivore - tree Swallow; and omnivore - American black duck) generalized linear models, I revealed associations between estimated species abundance and water flow, water level, distance from the river mouth (river kilometer), site position in relation to a dam (e.g. above, below, or not at a dam), and adjacent land cover composition.</p>
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Potts, Tavis William. "Sustainability indicators in marine capture fisheries." Connect to this title online, 2003. http://eprints.utas.edu.au/234/.
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Vinluan, Edlin Artuz. "Survival of Microbial Indicators In constructed Wetlands." Thesis, The University of Arizona, 1996. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0275_sip1_w.pdf&type=application/pdf.
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Giesen, Myra J. "Late prehistoric populations in the Ohio area : biological affinities and stress indicators /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487778663284737.
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Krutsinger, Roxane. "Evaluation of Grassland Restoration Success in Illinois Using Indicators of Ecosystem Function." Thesis, Southern Illinois University at Edwardsville, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1556741.
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<p> Grasslands are known to have been an important ecosystem in the Illinois landscape prior to European settlement. They have been severely impacted by changes in land use such as the conversion of native grasslands to agricultural land for the production of crops and livestock. Grassland ecosystems are known to provide several essential ecosystem functions that are important for the maintenance of the ecosystem and for human survival. Some of the ecosystem functions associated with grasslands include: nutrient cycling, carbon sequestration, and the cleansing of environmental contaminants from water or soil. As grasslands are converted to agricultural use, their ability to perform these ecosystem functions are greatly impaired or lost completely. Due to their recognized importance, grassland restoration projects have been given high priority by conservationists and governmental agencies around the world. Some grassland restorations aim to restore the native vegetation including the great species richness that grasslands, and prairie ecosystems in particular, are known for. Other projects, like the Conservation Reserve Program (CRP), aim to restore one of the vital ecosystem functions that grasslands provide. The measure of success for a grassland restoration has largely been evaluated using species composition and indices of species richness and evenness. These types of measurements do not directly assess the ability of a restoration site to perform the ecosystem functions of a native grassland. The aim of this study is to determine if ecosystem function is recovered over time since restoration. This will be accomplished using a chronosequence of grassland restorations at the Nature Institute in Godfrey, IL ranging from 1 year to 25 years since restoration. Several indicators of ecosystem functioning will be assesses at each site including: soil bulk density, soil organic matter, and peak standing crop. The differences in these characteristics among the sites were analyzed by one-way ANOVA followd by Tukey’s HSD test if significant. All properties were analyzed using linear regression to assess their fit to a linear model. Soil bulk density was found to moderately but significantly decrease in response to time since restoration (<i>p</i> = 0.0049) indicating a recovery from soil compaction and improved soil structure. Differences were detected in soil organic matter among the sites, but no linear trend in response to time since restoration was detected. Similarly with peak standing crop, differences were detected among the sites, but no linear trend with time since restoration. The lack of a predictable recovery in soil characteristics over time was attributed to differences in historical land use. In order to strengthen this study in the future, analysis of a remnant prairie and older restoration sites should be examined.</p>
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Hennig, Helmke Friedrich-Karl Otto. "Baseline surveys and metal binding proteins as metal pollution indicators." Doctoral thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/22479.
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Bibliography: pages 304-309.<br>The field of metal determination as a part of pollution studies, has been critically examined and metal pollution may be defined in one simple statement: The presence of metal binding proteins confirms toxic metal pollution. It has been shown that current methods of metal determination in biological systems are of little use. This has been illustrated by both a review of metal concentration in Southern African coastal water, sediments and biotopes, and by a comparative baseline study of organisms from Gough Island and Mar ion Island. These showed that extrapolation of results from one geographical area to another are invalid and that this interpretation is made difficult by factors such as age, sex, size life stage of the organisms. Furthermore, it was shown that many reports on metal pollution do not even mention fundamental information such as the size or the sex of the animals. Metal pollution could be linked to metal binding protein through an independent pollution er i ter ia, for example, the out of season moulting of crayfish. The new definition of metal pollution has then been tested by application to five different organisms (crayfish, Jasus lalandii; hermit crab, Diogenes brevirostris; shrimp, Palaemon pacificus; black mussel, Choromytilus meridionalis and limpet, Patella granularis) kept under identical conditions and it was shown that a much more meaningful interpretation of the results could be made. The new definition was al so tested with two naturally occurring metal accumulating organisms (whelk, Bullia digitalis and "kikuyu" grass) and it was shown that dramatic increases in metal may not necessarily be toxic. It was concluded that less effort and time should be spent on metal analysis in determination of metal pollution and attention should rather be directed to the presence or absence of metal-binding proteins.
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Greffard, Marie-Helene. "Chironomids as indicators of environmental change in shallow lakes of northeastern United States." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86992.
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Despite the widespread use of chironomids in biomonitoring and paleoenvironmental research to infer environmental change, there is disagreement over the level of taxonomic resolution required for meaningful ecological interpretations. An objective of my thesis was to evaluate the differences in environmental inferences drawn at two different levels of taxonomic resolution. I found similar results between both levels of resolution with both live and sub-fossil datasets, but a number of taxa had different ecological preferences when examined at different resolutions. Another objective was to develop a chironomid-based training set, to identify the biotic and abiotic environmental variables that explain a significant amount of variation in the structure of surface sediment chironomid assemblages and to develop transfer functions for these environmental variables. Turbidity, dissolved inorganic carbon and drainage ratio were found to be the most influential environmental variables in our lake-set and robust transfer functions were developed for turbidity and chlorophyll a.<br>Les chironomides sont souvent utilisées dans la recherche paléo-environnementale des lacs pour reconstruire les changements environnementaux. Même si les chironomides sont utilisées largement comme indicateur biologique, il y a un désaccord concernant la résolution taxonomique utilisée pour obtenir des interprétations écologiques significatives. Le premier objectif de l'étude était de comparer les inférences environnementales obtenues d'analyses réalisées selon deux résolutions taxonomiques différentes; d'une part à résolution fine et d'autre part à résolution grossière. La majorité des résultats étaient similaires, cependant, quelques taxa avaient des préférences écologiques variées lorsqu'elles sont étudiées à des résolutions différentes. Le deuxième objectif était de calibrer les chironomides récupérées dans des sédiments de surface avec les variables environnementales de 26 lacs peu profonds dispersés dans le nord-est des États-Unis et de développer, lorsque possible, des modèles d'inférences. La turbidité, le taux de carbone non-organic dissous, et le ratio de drainage ont été identifiés comme les variables environnementales qui ont une grande influence sur la structure des communautés des chironomides dans nos lacs d'études.
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Ravenscroft, John Elmer. "Evaluation of survival and recovery characteristics of bifidobacteria as indicators of fecal pollution of water." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1613.
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Thesis (M.S.)--West Virginia University, 2000.<br>Title from document title page. Document formatted into pages; contains xi, 138 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 133-137).
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Erdner, Deana Lynn 1969. "Characterization of ferredoxin and flavodoxin as molecular indicators of iron limitation in marine eukaryotic phytoplankton." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/45490.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 1997.<br>"Funding was provided by a Department of Energy Graduate Fellowship for Global Change and an Exploratory Research Agreement No. RP8021-05 from the Electric Power Research Institute."<br>Includes bibliographical references.<br>by Deana L. Erdner.<br>Ph.D.
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Van, Heerden Johannes Hendrik. "Peripheral blood mononuclear cells as non-invasive diagnostic indicators of stress-associated neural states." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/4347.
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Includes abstract.<br>Includes bibliographical references (leaves 155-181).<br>Researchers have demonstrated the ability to predict psychopathological states from human peripheral immune tissure transcriptional profiles, using microarrays. Although evidence in support of such an approach as a viable diagnostic avenue within psychiatric settings is accumulating, it remains to be demonstrated, in an animal model, that transcriptional changes in peripheral tissue targets are paralleled by specific gene expression changes in neural tissues.
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Gumbleton, Sarah. "Parasitic Indicators of Foraging Strategies in Wading Birds." Thesis, NSUWorks, 2018. https://nsuworks.nova.edu/occ_stuetd/484.
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Feeding ecology and trophic interactions of six species of wading birds were explored through a combined analysis of stable isotope profiles and endoparasite communities. Stable isotopes broadly characterize the feeding preferences and geographic information, while parasite communities reflect long-term trends in feeding ecology. Deceased birds were obtained from four South Florida wildlife rehabilitation organizations. Of the 81 birds dissected, 73 contained parasites. Parasites were predominately found within the gastrointestinal tract. Host and range extensions were noted for several parasite taxa. Bird host species had a significant effect on the parasite community (P=0.001) while wildlife center location and maturity status did not. Stable nitrogen (δ15N) values for pectoral muscle tissues, representing approximately 24 days, ranged from 6.44 to 13.48‰ while stable carbon (δ13C) values ranged from -33.39 to -11.66‰. δ13C varied significantly among location (P=0.0002) and δ15N varied significantly among species (P15N and δ13C was analyzed in combination; bird species (P=0.001) and location (P=0.001) were significantly different. By using this combined approach of stable isotope analysis and parasite identification, it was possible to elucidate more components of bird feeding ecology. Stable isotope analysis provided knowledge on trophic interactions based on δ15N values, while δ13C was used to determine the differences in geographic foraging location. As endoparasites are acquired trophically via food-web interactions, identifying the parasite community allowed for trophic links to be drawn between organisms present within the same environment. Combining these two techniques allows for an abundance of information on feeding ecology and trophic interactions to be obtained.
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Flanagan, Neal E. "Comparing ecosystem structure and function of constructed and naturally occurring wetlands : empirical field indicators and theoretical indices /." Connect to resource, 1997. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1242846242.
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Öster, Mathias. "Biological diversity values in semi-natural grasslands : indicators, landscape context and restoration." Doctoral thesis, Stockholm University, Department of Botany, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1352.
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<p>Semi-natural grasslands, which are a declining and fragmented habitat in Europe, contain a high biodiversity, and are therefore of interest to conservation. This thesis examines how plant diversity is influenced by the landscape context, and how plant and fungal diversity can be targeted by practical conservation using indicator species and congruence between species groups. Reproduction and recruitment of the dioecious herb <i>Antennaria dioica </i>was also investigated, providing a case study on how fragmentation and habitat degradation may affect grassland plants.</p><p>Grassland size and heterogeneity were of greater importance for plant diversity in semi-natural grassland, than present or historical connectivity to other grasslands, or landscape characteristics. Larger grasslands were more heterogeneous than smaller grasslands, being the likely reason for the species-area relationship.</p><p>A detailed study on <i>A. dioica </i>discovered that sexual reproduction and recruitment may be hampered due to skewed sex-ratios. Sex-ratios were more skewed in small populations, suggesting that dioecious plants are likely to be particularly sensitive to reduced grassland size and fragmentation.</p><p>A study on indicators of plant species richness, used in a recent survey of remaining semi-natural grasslands in Sweden, revealed several problems. A high percentage of all indicator species were missed by the survey, removing an otherwise significant correlation between indicator species and plant species richness. Also, a null model showed that the chosen indicator species did not perform significantly better than species chosen at random from the available species pool, questioning the selection of the indicators in the survey. Diversity patterns of the threatened fungal genus <i>Hygrocybe</i> were not congruent with plant species richness or composition. Plants are thus a poor surrogate group for Hygrocybe fungi, and probably also for other grassland fungi. Implications from this thesis are that conservation of semi-natural grasslands should target several species groups, and that an appropriate scale for plant conservation may be local rather than regional.</p>
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Morse, David Linn. "Choline metabolites as diagnostic and therapeutic response indicators for breast cancer." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280525.
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Choline metabolites are elevated in breast cancer, decrease in response to effective therapy and are detected non-invasively by magnetic resonance modalities. Decreases in choline metabolites occur early-on after initiation of treatment. There is potential for use of choline metabolites as non-invasive diagnostic and therapeutic response indicators. Choline metabolites are detected in vivo by magnetic resonance spectroscopy (MRS) in broad resonances which are composites of multiple compounds. Tumor extract studies have suggested that phosphocholine (PCho) is the component of these resonances with the greatest potential for use as a diagnostic marker or therapeutic response indicator. Since other compounds present in these broad resonances vary in concentration with cancer progression and in response to therapy, changes in these other resonances can potentially diminish the overall signal or dampen the detectable therapeutic response. The ability to resolve and quantify PCho in vivo increases the sensitivity of this detection method, and hence, increases its potential utility. Herein is reported the in vivo resolution and quantification of PCho in a human breast cancer xenograft model in mice. A significant PCho decrease is detected following treatment with the taxane docetaxel. This PCho decrease is correlated with the diffusion-weighted magnetic resonance imaging (DWMRI) measured increase in tumor water mobility, and with mitotic catastrophe, a non-apoptotic mode of cell death. By studying model system of human breast cancer cells, other metabolites in the choline pathway varying with cancer progression are determined, and the transcriptional expression of genes in the choline pathway is quantified. From these data and enzyme activity data reported by other groups, a model is proposed where a number of metabolic perturbations combine to elevate PCho in breast cancer. These perturbations include the elevation of choline transporter, choline kinase, and phospholipase activities, in combination with decreased CTP:PCho cytidylyltransferase (CCT) activity. By changes in metabolites and gene expression following therapy, it is proposed that increased CCT activity combined with decreased phospholipase and GPC phosphodiesterase activity lead to decreased PCho. In addition, expression of a putative choline transporter (CTL1 variant A) and a putative choline kinase (CHKL) is quantified in human breast cells.
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Chu, King-hei Vincent. "Derivation of environmental quality guidelines based on tissue burden of toxic pollutants in the green lipped mussel Perna viridis /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120281.
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Matusiewicz, Malgorzata. "Using biochemical indicators to determine the recommended dietary allowance (RDA) and body ascorbate compartmentalization for juvenile rainbow trout /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487857546387809.
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Kenkel, Julie Ann. "Identifying indicators of nitrogen pollution in vegetation and soils in the Grand Canyon region." Thesis, Northern Arizona University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1537787.
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<p>Anthropogenic contributions to global reactive N pools have more than doubled since the agricultural and industrial revolutions. Although N is an essential plant nutrient, enrichment of reactive N in air pollution can initiate a cascade of deleterious effects including increased smog and haze, ecosystem acidification, increased invasion of non-native grasses, and reduced biodiversity. However, the ecological impacts of N deposition in historically N-limited, semi-arid regions are not well understood. Here, I report the findings from field studies of automobile pollution in Grand Canyon National Park (GCNP; Study 1) and long-range N deposition from the nearest coal-fired power plant, the Navajo Generating Station (NGS; Study 2). To identify potential indicators of N enrichment, I measured four different metrics of N pollution: 1) atmospheric nitrogen oxides (NO<sub>x</sub>) with Ogawa passive air samplers, 2) natural abundance δ<sup>15</sup>N signatures of soil and foliage of pinyon pine (<i>Pinus edulis</i>), 3) spectral analysis of pinyon pine foliar nitrogen, and 4) leaf area on pinyon pine branches. </p><p> In both studies, the amount of NO<sub>x</sub> measured by the Ogawa samplers decreased significantly with increasing distance from N-source. In heavily trafficked sites in GCNP, atmospheric NO<sub>x</sub> was 52% higher at the roadside compared to 30 m away from the road. Atmospheric NO<sub>x</sub> on the Paria Plateau was 54% higher 25 km from NGS compared to 50 km away from the coal-fired power plant. Across both study areas, δ<sup>15</sup>N values in plant tissues reflected inputs from emission sources. According to our data, the biggest ground level N inputs in GCNP are from vehicular emissions, not NGS. Although I detected patterns in terrestrial responses to both small and larger-scale N deposition gradients, future field studies focused on plant community composition and sensitive biological indicators are needed to determine ramifications of elevated N inputs caused by pollution from motor vehicles and power plants. </p>
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Oguma, Andrew Y. "Assessing the Effects of Low-Level Lead Contamination in Freshwater Sediments using Community-Level and Functional Indicators." Thesis, University of Louisiana at Lafayette, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622951.
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<p> Anthropogenic lead releases into the environment often end up in aquatic sediments. Ecotoxicologists have historically studied biological effects of toxicants, such as lead, using individuals or populations as models in laboratory settings. It has recently been suggested that because such bottom-up approaches can be difficult to extrapolate to actual effects of contaminants in the field, more research should take a top-down perspective. My project therefore aimed to investigate sediment lead effects at the community level, as well as on ecosystem function. Studies were conducted in a lake with a gradient of low-level sediment lead contamination. An assessment of benthic macroinvertebrate communities at fifty points in the lake revealed a negative correlation between sediment lead concentration and community abundance and diversity. Leaf-litter bags were deployed at thirty of the same points and decomposition rate was assessed after thirty days. Analyses indicated that decomposition rate decreased with increasing sediment lead concentration. Acute lead bioassays, using benthic macroinvertebrates collected from different areas of the lake, revealed that communities from the contaminated area were more tolerant to lead than were communities from uncontaminated areas. The pattern of increased community tolerance as a result of chronic exposure to low-level sediment lead was confirmed with macrobenthic communities that had been pre-exposed to environmentally-relevant lead concentrations for eighteen months in sediment mesocosms. Communities exposed to elevated lead levels had an increased tolerance when exposed to lethal lead levels. This was supported by the observed reduction in abundance and diversity that correlated with an increase in benthic macroinvertebrate community tolerance to lead. Additionally, reductions in leaf-litter decomposition, a vital ecosystem function in lentic systems, were also correlated with reductions in benthic macroinvertebrate abundances. Overall, the low-levels of sediment lead in the lake system appeared to have adverse effects on both structural and functional aspects of ecological integrity. Because sediment concentrations in the lake system were largely below widely accepted guidelines that are considered to be protective of benthic macroinvertebrates, my results have implications for risk-assessment in lentic systems contaminated with lead.</p>
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Tucker, Sally Sue. "Morphological and physiological traits as indicators of drought tolerance in tallgrass prairie plants." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/4628.
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Master of Science<br>Department of Biology<br>Jesse B. Nippert<br>The Konza Prairie in northern Kansas, USA contains over 550 vascular plant species; of which, few have been closely studied. These species are adapted to environmental stress as imposed by variable temperature, precipitation, fire, and grazing. Understanding which plant traits relate to drought responses will allow us to both predict drought tolerance and potential future shifts in plant community composition from changes in local climate. Morphological and physiological measurements were taken on 121 species of herbaceous tallgrass prairie plants grown from seed in a growth chamber. Gas exchange measurements including maximum photosynthetic rate, stomatal conductance to water vapor, and intercellular CO[subscript]2 concentration were measured. All plants were exposed to a drought treatment and were monitored daily until stomatal conductance was zero. At this point, critical leaf water potential (Ψ[subscript]crit), an indicator of physiological drought tolerance was assessed. Other measurements include root length, diameter, volume, and mass, leaf area, leaf tissue density, root tissue density, and root to shoot ratio. Traits were compared using pair-wise bivariate analysis and principal component analysis (PCA). A dichotomy was found between dry-adapted plants with thin, dense leaves and roots, high leaf angle, and highly negative Ψ[subscript]crit and hydrophiles which have the opposite profile. A second axis offers more separation based on high photosynthetic rate, high conductance rate, and leaf angle, but fails to provide a distinction between C[subscript]3 and C[subscript]4 species. When tested independently, grasses and forbs both showed drought tolerance strategies similar to the primary analysis. Matching up these axes with long term abundance data suggests that species with drought tolerance traits have increased abundance on Konza, especially in upland habitats. However, traits that relate to drought tolerance mirror relationships with nutrient stress, confounding separation of low water versus low nutrient strategies. My results not only illustrate the utility of morphological and physiological plant traits in classifying drought responses across a range of species, but as functional traits in predicting both drought tolerance in individual species and relative abundance across environmental gradients of water availability.
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Hoare, Annabel. "An evaluation of downland turf re-creation, using invertebrates as indicators." Thesis, Bournemouth University, 1999. http://eprints.bournemouth.ac.uk/402/.
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Seven study sites within the South Wessex Downs Environmentally Sensitive Area (SWD ESA) were used to evaluate re-created downland turf, a habitat created under one of the scheme management options. The novel habitat was compared to adjacent areas of established downland and to the edges of arable fields, by collecting vegetation data, and using invertebrates as indicators of habitat quality. The recreated downland sites were re-seeded 1 to 3 years before the study. The new habitat was influenced by adjacent established downland and calcicolous species were found colonising the: edges of the re-created downland. The edges of established downland were degraded in terms of plant species richness, probably by previous arable use in adjacent fields. It was found that the re-created downland was being used by several butterfly species for breeding as well as for nectaring and that these activities were concentrated around the edges of the habitat. A second indicator group, the Homoptera, were also found on the re-created downland and, although no evidence of breeding was gathered, some of the species found on the habitat were characteristic of established downland. A third aspect of the study focused on the effect on associated herbivores of the nonnative varieties of downland species which are sown into the re-created downland. It was found that these were not as easily digested as a native variety and that although the larvae gained more weight they pupated later, thus increasing their chances of predation. This has not previously been demonstrated and it is hoped that they will help improve the management of the SWD ESA in future years.
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Sanchez, Luis R. "Removal of bacterial indicators and pathogens from dairy wastewater by a treatment system." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284075.
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An integrated wastewater treatment facility at a dairy in Glendale, Arizona, consisting of an upper subsystem (solids separators, anaerobic lagoons, and aerobic ponds) and lower subsystem (wetland subsystems) has been proven to be successful in reducing indicator organisms and potential pathogens (bacteria, enteric viruses, and parasites). The collection sump of the new integrated system collects all dairy wastewater and pumps it to solid separators, which then flows by gravity to anaerobic lagoons and aerobic ponds. The upper subsystem achieved significant microbial reductions of >98 percent for total coliform, >91 percent for coliphage, >95 percent for enterococci, >91 percent for Listeria monocytogenes, and >99.9 percent for Cryptosporidium . Additional reductions although limited were observed in the outflow from the wetland cells.
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Allen, Laura. "The application of biodiversity indicators to infer ecosystem health in regenerating tropical forest." Thesis, University of Glasgow, 2019. http://theses.gla.ac.uk/40949/.
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There are an overwhelming number of biodiversity indices and indicators available for ecologists and conservationists to use when seeking to understand how biodiversity responds to human disturbance. In choosing between measures there is often an underlying assumption that if a measure works well for one group it will be equally applicable to another. In this study, I use multiple taxa to explore the performance of a wide range of alpha and beta diversity measures for studying biodiversity responses to human disturbance in tropical forest. I sampled 18 sites along a gradient of human disturbance from primary tropical forest to banana monocultures in Peru. I chose three taxonomic groups and one audio approach, which have all been suggested to be useful indicators for studying biodiversity responses to disturbance: orchid bees (n = 1783), dung beetles (n = 3787), butterflies (n = 2506) and soundscape samples (n = 6600). This allowed me to identify how these groups responded to disturbance, which diversity measures were most sensitive for detecting those changes and whether the same measures were suitable for all groups. I used Hill numbers to measure alpha diversity and explored beta diversity by looking at changes in community composition and two new measures of beta diversity: redundancy and representativeness. To see how the diversity patterns changed when taxonomic similarity was considered, I used a recently developed family of similarity-sensitive diversity measures and compared the results of these against more traditional measures. I found that the diversity indices that were best for detecting disturbance patterns varied widely among taxonomic groups. For dung beetles, species richness and community composition were the most effective measures, whereas these performed poorly for orchid bees. Abundance and redundancy were more sensitive for detecting a response to disturbance in orchid bees. Using the butterfly dataset, I show that the inclusion of species similarity completely changed the diversity patterns found across the disturbance gradient. The similarity of species present in a community is likely to be important for the preservation of evolutionary adaptability and the provision of ecosystem functions and I therefore suggest that diversity measures based on similarity will be a useful additional tool for conservation and impact assessments. Acoustic diversity showed unintuitive responses to disturbance, with higher diversity detected in more disturbed forest, and more research is required to assess the performance of different acoustic indices in rainforest environments. Overall, my results demonstrate the importance of choosing diversity indices carefully to suit the taxa being studied to avoid missing important ecological responses, including a consideration of species similarity. I recommend that, where possible, multiple diversity indices and taxonomic groups should be used to reduce this risk and provide a comprehensive understanding of ecosystem patterns in response to environmental change.
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Cheung, Ka-hong. "Chromate toxicity assessment and detoxification by bacteria from the marine environment /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36249890.
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Sutanto, Yovita. "Manure from grazing cattle effects on soil microbial communities and soil quality in northern West Virginia pastures /." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3933.
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Thesis (M.S.)--West Virginia University, 2005.<br>Title from document title page. Document formatted into pages; contains vii, 72 p. : ill. (some col.), map. Includes abstract. Includes bibliographical references.
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Monson, Michael L. Jr. "The Effects of Increased Hay-Grain Ratio on Masai Giraffe Behavior, Health Indicators and Fecal Microflora Diversity." Cleveland State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=csu1475530272039469.
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Kwong, Pui-ki. "Surface water quality indicators in China and their implications for sustainability." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36618718.
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Dlamini, Nonhlanhla. "An assessment of the health status by non-specific stress indicators in early farming populations from central and southern Africa." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/26516.
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The adoption of an agricultural lifestyle had profound implications for nutritional ecology, health and behaviour of human populations. The goal of this project was to generate information about the health status and disease patterns of early farming populations from central and southern Africa. Skeletal material was obtained from various 'Iron Age' sites in South Africa, Ingombe Ilede from Zambia, and Sanga and Katoto from the Democratic Republic of Congo. Palaeopathological analyses was done through the examination of non-specific stress indicators that included cribra orbitalia/porotic hyperostosis, Harris lines, linear enamel hypoplasias, subperiosteal bone lesions and dental diseases. The evidence from palaeopathology indicated that the environments played a major role in causing differences observed at micro-scale level. It is suggested that the health problems of these agricultural peoples are a result of their sedentary lifestyle and aggregation, which promoted maintenance and spread of infectious diseases; as well as high carbohydrate diets and dependence on a few main foodstuffs that affected their iron levels. The individuals from the forest region were less healthy than those in the dry or wet savanna zones. Also, the impact of the stress experienced by these societies was not sufficient to cause stunted growth and thus did not affect their terminal heights. The complex relationship between the environment, socio-cultural factors and biology has shown that subsistence economy only influences a fraction of human behaviour, health and well being. The results of this study argue that generalisations about prehistoric farming peoples cannot be made, until further research work is done.
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Miniutti, Danielle M. "Bioindicators of Desorbed Contaminants Following Resuspension of Penobscot River Sediments." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/MiniuttiDM2007.pdf.
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Shepard, Gerald T. "Determination of a true biotic index and comparison of riffle and snag habitats in Bearskin Creek, Oneida County Wisconsin, using a modified biotic index /." Link to abstract, 2002. http://epapers.uwsp.edu/abstracts/2002/shepard.pdf.
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Bergolc, Melanie. "A paleoenvironmental analysis using fossil insects in late Quaternary deposits in Indiana and Ohio." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1092940677.
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Reese, Carol Jean. "Pigments as Indicators of a Response to Environmentally Induced Modification of a Coral-Algal Symbiosis." NSUWorks, 1990. http://nsuworks.nova.edu/occ_stuetd/363.
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The purpose of this study was to assess whether phagotrophy may be proportionally more important to coral nutrition with decreasing light intensity. An animal carotenoid pigment, possibly astaxanthin, isolated from Montastrea annularis was used as an indicator of phagotrophy. This carotenoid was measured in corals collected over a depth transect in the field and in corals exposed to varying amounts of food and light in laboratory experiments.
In the field, multiple cores of the same and different coral heads were collected at each of four depths, 4.6, 7.6, 18.3 and 22.9 m. In the laboratory, cores from the same coral head were maintained at three light intensities (0.024, 24 and 90 μE m-2s-l) with three feeding schedules at each intensity (no Artemia, 2-3 Artemia/ml, and 8-10 Artemia/ml).
The pigments from the corals' symbiotic algae, zooxanthellae, and from the coral polyp were acetoneextracted and quantitatively isolated by reverse-phase, high performance liquid chromatography (HPLC). Parametric statistics were used to determine whether carotenoid concentrations in corals varied significantly with depth along the transect in the field, or with light intensity or particulate food concentration in the laboratory.
In the field, mean concentrations of the animal carotenoid increased significantly between 7.6 and 18.3 m over a depth range from 4.6 to 22.9 m. A significant increase in animal carotenoid concentration was also found when 4.6 and 7.6 m data were pooled and compared with pooled data from 18.3 and 22.9 m. This suggests the possibility of two populations.
In the laboratory, animal carotenoid concentrations increased significantly with decreasing irradiance. However, at each individual light intensity the absolute concentrations of animal carotenoid were similar no matter what the feeding regime. Between the light intensities of 24 and 0.024 μE m-2s-l animal carotenoid content increased in corals fed 8-10 Artemia/ml and in un-fed corals. That no difference was found between light intensities in corals fed 2-3 Artemia/ml may be because of the high variability observed in animal carotenoid content for this group.
The animal carotenoid content from combined field and laboratory data varied proportionally with the natural logarithm of light. It appeared that below approximately 200-400 μE m-2s-l (10% and 20% PAR) the rate of change in carotenoid content increased with respect to light.
The animal carotenoid:peridinin ratio may reflect the relative importance of phagotrophy to coral nutrition. The ratio increased with depth with one exception.
In conclusion, the carotenoid isolated from the coral polyp increased with decreasing irradiance. This increase may result from a carotenoid-rich diet. Such an increase may reflect an increase in phagotrophy.
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Mengel, Doreen C. "Amphibians as Wetland Restoration Indicators on Wetlands Reserve Program Sites in Lower Grand River Basin, Missouri." Thesis, University of Missouri - Columbia, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13850742.
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<p> Globally, amphibians have suffered dramatic population declines in the past twenty years with habitat destruction implicated as the primary threat. The Natural Resources Conservation Service’s Wetlands Reserve Program (WRP) restores wetlands on marginal agricultural land and is a means to restore the spatio-temporal wetland habitat required by amphibians to prevent, reverse, or stabilize declining population trends. The goal of WRP is “to achieve the greatest wetland functions and values, along with optimum wildlife habitat, on every acre enrolled in the program.” Functions and values are defined as the hydrological and biological characteristics of wetlands. A key unanswered question is to what extent is this goal being achieved? Amphibians enable quantifying the WRP goal due to their life-history requirements and explicit incorporation of their habitat needs into WRP plans. My research goal was to determine if hydrological and biological wetland characteristics had been restored to WRP sites in the Lower Grand River basin, north-central Missouri, based on distribution, recruitment success, and relative species richness estimates for members of a regional species pool. I identified three design strategies applied to WRP sites over time: walk-away, maximize hydrology, and naturalistic; the latter emphasizing restoring process as well as structure; and evaluated if design strategy was a useful covariate for restoration efforts. I encountered 10 amphibian species representing 59% of the regional species pool. Design strategy was not a predictive site-level covariate as sites within all three design strategies had varying hydrological wetland conditions resulting in greater habitat heterogeneity than anticipated on maximize hydrology and walk-away sites and less than anticipated on naturalistic sites. Amphibian detections occurred across all sites resulting in no difference among design strategy as the degree of heterogeneity in habitat conditions at the within site-scale demonstrated that amphibians were responding to ecological conditions that occur at a finer resolution than site. Results, irrespective of design strategy, indicate seven of the detected species or groups were widely- distributed, two were moderately- distributed, and two were sparsely distributed on WRP sites indicating hydrological wetland characteristics have been restored to sites given the moderate- to wide-distribution of species associated with both seasonal and permanent wetlands. Although species were successfully recruiting young into adult populations, only leopard frogs had high estimates of recruitment success whereas the remaining species had moderately high to moderate to low recruitment estimates indicating biological wetland characteristics are somewhat lacking to lacking for these species. Results from the relative species richness assessment indicate that, whereas 74% of the sites provided some degree of wetland habitat for members of the regional species pool over the course of the field season (7 March – 19 September), 52% of the sites lacked suitable habitat conditions during the peak of amphibian breeding and larval development (May through July). Targeting management actions that result in suitable seasonal wetland habitat conditions (shallow, vegetated wetlands that gradually dry by mid-to late-summer) throughout the time needed for species to complete their life history requirements is one method to increase the biological wetland value of restored WRP sites. Results show the value of WRP at conserving and restoring river-floodplain amphibians; however, achieving optimum wildlife habitat on every enrolled acre will be difficult at a site-level scale as habitat requirements, although overlapping, vary widely for the full range of species. Providing for all species in the regional species pool requires sites that transverse both the longitudinal and lateral floodplain gradient. If WRP is to realize its full potential, there must be recognition that optimum wildlife habitat can be defined at multiple spatial and temporal scales that match the landscape setting. Optimum wildlife habitat at a wetland scale is not the same as optimum wildlife habitat at the floodplain scale. The intent of WRP is to convert marginal, flood-prone agricultural lands back into wetlands so enrollment of lands located outside the active floodplain may be impracticable or unrealistic. Whereas attaining optimum wildlife habitat on every acre enrolled in the program may not be an achievable objective, providing optimum wildlife habitat for members of a regional species pool within an appropriately defined geography that includes both a longitudinal and lateral gradient represents an objective that is both desirable and attainable.</p><p>
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Green, Melissa V. "Prevalence and Distribution of Staphylococcus aureus and Other Potential Health Risk Indicators in South Florida Beaches." NSUWorks, 2004. http://nsuworks.nova.edu/occ_stuetd/281.
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This report is part of the first study to evaluate the potential use of non-traditional and non-enteric bacteria as indicators of health risk in recreational waters and beach sand in south Florida. This study evaluated the possibility of utilizing a series of novel indicators including Staphylococcus aureus, Clostridium perfringens, Pseudomonas aeruginosa, and Vibrio species to assess beach quality. To evaluate the usefulness of these 4 novel microorganisms as potential indicators, 3 south Florida beaches were sampled for a 1 year period and during the year, the distribution across 500m of the beach (spatial analysis) and location (interstitial or attached) of the bacteria were obtained. At Hollywood Beach, Fort Lauderdale Beach, and Hobe Beach in Miami, wet sand, dry sand, and seawater samples were taken bimonthly and analyzed in a laboratory at Florida Atlantic University. In the laboratory, traditional microculture methods recommended by the USEPA were utilized to analyze the samples and bacteria.
Analysis of the yearly sampling showed that dry sand, above the high tide mark contained highly elevated and significantly more bacteria than wet sand and seawater. Furthermore, S. aureus showed promise as a reliable indicator of health risk as the highly frequented beaches of south Florida correlated with high levels of S. aureus and some non-enteric illnesses, as displayed through a beach questionnaire, were apparent with high levels of S. aureus. Elevated levels of S. aureus may be due to regrowth in the sand as shown by the fact that S. aureus were found more often attached than residing in the interstitial spaces and this suggests viable activity of the bacteria and thus, regrowth.
Positive correlations between the traditional enteric indicators and the potential indicators were displayed as well. Clostridium perfringens in the wet sand highly correlated with fecal coliforms (r = 0.98), E. coli (r = 0.87), and enterococci (r = 0.53) at Hobe beach, as did S. aureus which correlated with fecal coliforms (r = 0.81) and enterococci (r = 0.81) at Hollywood Beach.
Most of the tested bacteria in this study were found to be attached to sand grains, especially S. aureus. Attachment to substrates requires the use of flagella, polysaccharides, or capsules and thus, attachment suggests metabolic activity. The bacteria, being viably active, can then exponential grow, and this further suggests regrowth in the sand. This regrowth in the sand may then pose a significant public health risk to people at the beach, especially young children, as these organisms have been shown to cause several non-enteric illnesses such as ear infections and skin rashes.
The macrospatial analysis across the beach, up the beach, and down in the sand revealed some unevenness in the sand. The tendency for bacteria to not spread, and thus, not be even across the beach again supports the idea that the bacteria are regrowing in the sand. The sand can therefore serve as a reservoir from various sources such as runoff, beach attendees, and birds and in this reservoir, extremely high levels of potentially pathogenic bacteria can remain. The seemingly perfect environment of south Florida beaches, a tropical environment, the warm temperatures year round, high humidity, rainfall year round therefore creates an adequate niche for potentially pathogenic bacteria to reach significantly elevated levels. This study then demonstrates the need to analyze novel organisms (enteric and non-enteric) in beach sand to ensure public health safety at south Florida beaches.
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Vázquez, Rosa I. "Decomposition rates of organic amendments and soil organic matter fractions as indicators of soil quality : an on-farm study of organic and conventional dairy farms in Ohio /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488202678776313.
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Simaika, John Pascal. "Practical conservation planning from local to continental scales using freshwater invertebrates." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/18051.
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Thesis (PhD)--Stellenbosch University, 2011.<br>ENGLISH ABSTRACT: Dragonflies (Insecta: Odonata) are a valuable tool for assessing aquatic systems and have been used as indicators of ecological health, ecological integrity, and environmental change, including climatic change. In four separate studies I explored the usefulness of dragonflies as surrogates in biomonitoring, site prioritization and indication of global climate change. In the use of dragonflies for biomonitoring, I field-tested a freshwater ecological integrity index, the Dragonfly Biotic Index (DBI), based on dragonfly assemblages at the local scale, and compared the DBI to a standard freshwater benthic macroinvertebrate-based freshwater health index. Overall, dragonflies were more sensitive to changes in river condition than were macroinvertebrates, and the DBI site value and macroinvertebrate scores were highly significantly correlated. I conclude that dragonfly assemblages in the form of a DBI are an excellent tool for environmental assessment and monitoring freshwater biodiversity, with the potential to replace benthic macroinvertebrate-based freshwater quality assessments.
In the second study, I used the DBI to prioritize sites for conservation action in South Africa. Using a selected set of top prioritized sites, I compared the DBI’s performance to that of a rarity-complementarity algorithm. Site prioritization using the DBI reveals that CFR sites protect Red Listed taxa rather well. The rarity-complementarity algorithm represents all species, but without greater emphasis on the rare and threatened species. I conclude that the DBI is of great value in selecting biodiversity hotspots, while the algorithm is useful for selecting complementarity hotspots.
The third study was made possible by the recent completion of a continental assessment of freshwater biodiversity, which revealed that patterns of richness and threat of four well-studied aquatic taxa largely coincide at the continental scale. Using only dragonflies, I built a protected areas network for Africa using spatial planning software. I then compared the performance of the existing African reserve network and that of known global biodiversity hotspots against the model, and identified sites of conservation concern. Although the current reserve network covers 10.7% of the landscape, the proportional representation of species geographic distributions in reserves is only 1.1%. The reserve network is therefore inefficient, and many areas of conservation priority that are not formally protected remain. The advantage of operating at the fine scale, while covering a large geographic area is that it shifts the focus from the large-scale hotspots to smaller priority areas within and beyond hotspots.
In the fourth study, I created species distribution models of dragonflies in an El Niño-prone biodiversity hotspot in South Africa, and predicted the changes in species richness, geographic range and habitat suitability, forty and eighty years from now. According to the model results of two different emissions scenarios, at least three species will be lost from the area by 2050, and four by 2080. The remaining species are predicted to persist with reduced geographical ranges, at generally higher elevations. Most species presented here thrive quite well in artificial environments, that is, engineered ponds or dams. It is therefore unlikely that loss in connectivity will play a role for these species.<br>AFRIKAANSE OPSOMMING: Naaldekokers (Insecta:Odonata) is waardevolle instrumente om akwatiese sisteme te assesseer, en is al gebruik as aanwysers van ekologiese gesondheid, ekologiese integriteit en omgewingsverandering, insluitend klimaatsverandering. In vier studies het ek die nut van naaldekokers as surrogate in biomonitering, area prioritisering en indikasie van globale klimaatsverandering ondersoek. In die benutting van naaldekokers in biomonitering, het ek ´n varswater ekologiese integriteits indeks, die Dragonfly Biotic Index (DBI), wat gebaseer is op naaldekokergemeenskappe op die plaaslike skaal, getoets en dit vergelyk met ´n standaard bentiese makroinvertebraat-gebaseerde varswater gesondheids index. Naaldekokers was meer sensitief vir veranderinge in riviertoestand as makroinvertebrate, en die DBI lokaliteit waarde en makroinvertebraat telling was beduidend gekorreleer. Die gevolgtrekking was dat naaldekoker gemeenskappe in die vorm van die DBI ‘n uitstekende instrument is vir omgewings assessering en die monitering van varswater biodiversiteit, met die potensiaal om bentiese makroinvertebraat-gebaseerde varswaterkwaliteit assessering te vervang.
In die tweede studie, het ek die DBI gebruik om areas te prioritiseer vir bewaringsaksie in Suid Afrika. Met die gebruik van ‘n geselekteerde set top prioriteit areas, het ek die DBI se prestasie vergelyk met die van ‘n rariteit-komplemetariteit algoritme. Area prioritisering met die gebruik van die DBI het aangedui dat CFR areas taxa op die Rooi Lys goed beskerm. Die rariteit-komplementariteit algoritme verteenwoordig alle spesies, maar beklemtoon minder skaars en bedreigde spesies. Die gevolgtrekking was dat die DBI van meer waarde is in die selektering van biodiversiteits ‘hotspots‘, terwyl die algoritme nuttig is vir die selektering van komplementariteits ‘hotspots‘.
Die derde studie was moontlik gemaak deur die onlangse voltooiing van ‘n kontinentale assessering van varswater biodiversiteit, wat aangedui het dat patrone van rykheid en bedreiging van vier goed-bestudeerde akwatiese taxa grootliks ooreenstem op die kontinentale skaal. Met die gebruik van naaldekokers, het ek ‘n beskermde area netwerk gebou vir Afrika met ruimtelike beplannings sagteware. Ek het die prestasie van die bestaande Afrika reservaatnetwerk en die van bekende globale biodiversiteit ‘hotspots‘ vergelyk teen die model, en het areas van bewaringsbelang geidentifiseer. Alhoewel die bestaande reservaatnetwerk 10.7% van die landskap dek, is die proporsionele verteenwoordiging van spesies se geografiese verspreiding net 1.1%. Die reservaatnetwerk is dus onvoldoende en baie areas van bewaringsbelang is nie formeel beskerm nie. Die voordeel van op die fyn skaal werk terwyl ‘n groot geografiese are gedek word, is dat dit die fokus van groot skaal ‘hotspots‘ na kleiner prioriteits areas binne en buite ‘hotspots‘ verskuif. In die vierde studie, het ek spesies verspreidingsmodelle van naaldekokers geskep in ‘n El Nino-geneigde biodiversiteits ‘hotspot’ in Suid Afrika, en het veranderinge in spesies rykheid, geografiese verspreiding en habitatsgeskiktheid voorspel, veertig en tagtig jaar van nou af. Volgens die modelresultate van twee verskillende emissie scenarios, sal ten minste drie spesies verlore gaan uit die area teen 2050, en vier teen 2080. Daar word voorspel dat die oorblywende spesies sal voortduur in verkleinde geografiese areas, by groter hoogte bo seespieël. Die meeste spesies hier verteenwoordig floreer in kunsmatige omgewings, soos mensgemaakte damme. Dit is dus onwaarskynlik dat ‘n verlies in konnektiwiteit ‘n rol sal speel vir hierdie spesies.
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Kennard, Mark. "A quantitative basis for the use of fish as indicators of river health in eastern Australia." Connect to this title online, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20051004.155737/.
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Gadbois, Nicholas Brian. "Using Chaetognatha as Indicators of Water Masses in the Florida Current, Broward County, Florida." NSUWorks, 2013. http://nsuworks.nova.edu/occ_stuetd/168.
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Zooplankton samples and water mass measurements were conducted along a 10 km long, east-west transect off the coast of southeast Florida during 2007. Temperature and salinity measurements were recorded using a conductivity-temperature-depth (CTD) sensor, and current direction and magnitude measurements were recorded using an acoustic Doppler current profiler (ADCP). Daylight zooplankton samples were collected using a 335 μm mesh bongo net at surface 0-25 m and 0-150 m (nearshore) and 0-200 m (offshore), at three stations, for 5 nonconsecutive months along the transect. Chaetognatha were separated from bulk zooplankton samples and identified to species; fifteen different species were found. Flaccisagitta enflata had the highest densities over the entire sampling period, followed by Serratosagitta serratodentata, and Krohnitta pacifica. ADCP data revealed the existence of a Subsurface Counter Current in conjunction with an offshore meander of the Florida Current during May, July, and September 2007. Abiotic data confirmed the presence of Continental Edge Water and Yucatan Water occupying different spatial and temporal scales, and the boundary between these two water masses existed as the western boundary of the Florida Current. The densities of each species were compared to the collection site’s temperature and salinity data. Densities of several species (Flaccisagitta enflata, Ferosagitta hispida, M. minima, and Sagitta bipuctata) demonstrated a correlation to temperature and S. bipunctata and Ferosagitta hispida showed a correlation to salinity. These species were associated with the front and peripheries of the Florida Current.
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Kwong, Pui-ki, and 鄺沛琪. "Surface water quality indicators in China and their implications for sustainability." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36618718.
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Geraghty, Maureen Elizabeth. "Physiological and molecular indicators of change in the intestinal microflora of postmenopausal women consuming soy and fructooligosaccharides (FOS)." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149013040.
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Staples, Peter G. "Freshwater tortoises Chelodina Longicollis Shaw and Emydura SP (Cooper Creek) : their potential as bio-monitors of environmental heavy metal contamination /." Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09AEVH/09aevhss794.pdf.
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Cheung, Ka-hong, and 張嘉康. "Chromate toxicity assessment and detoxification by bacteria from the marine environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45015351.
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Beghelli, Frederico Guilherme de Souza. "As relações de organismos bentônicos bioindicadores com a poluição por metais e metaloides em represas do sistema Cantareira, São Paulo /." Sorocaba, 2016. http://hdl.handle.net/11449/140278.
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Orientador: Viviane Moschini Carlos<br>Coorientador: Marcelo Luiz Martins Pompêo<br>Resumo: Vivemos atualmente, um cenário de crise hídrica mundial. Tal crise inclui tanto aspectos quantitativos quanto qualitativos ameaçando a segurança hídrica das sociedades humanas e os ecossistemas do planeta Terra. No Brasil, a região hidrográfica do Paraná destaca-se como região com maior densidade populacional, desenvolvimento econômico e industrial do país sendo, portanto, a região com maior demanda pelo recurso. No Estado de São Paulo desenha-se uma situação de crise hídrica agravada em ambos os aspectos. Do ponto de vista qualitativo, a Região Metropolitana de São Paulo destaca-se como aquela cujos mananciais encontram-se em situação mais impactada. O Sistema Cantareira, composto por um conjunto de cinco reservatórios é um dos principais sistemas fornecedores de água para esta região de intensas demandas e geradora de grandes impactos ambientais. A poluição de ambientes aquáticos por metais e metaloides é um problema mundial e frequentemente associado aos impactos gerados por regiões urbanas e industrializadas. Um agravante deste tipo de poluição, é o fato de os metais e metaloides não serem metabolizados pela biota, de forma que estes elementos tendem a se acumular, especialmente nos sedimentos, ao longo do tempo, com possibilidade de poluição das águas e dos organismos que habitam os ecossistemas aquáticos. Neste estudo, foram levantados dados referentes a qualidade da água e dos sedimentos de três reservatórios pertencentes ao Sistema Cantareira (Jaguari e Jacareí sendo ... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: A global water crisis is in course. This crisis include quantitative and qualitative aspects and it threatens the water security of human societies and of the Earth's ecosystems. In Brazil, the Paraná hydrographic region is the one with highest population density, economic and industrial development. As consequence, it is the hydrographic region in Brazil that demands highest amounts of water. São Paulo state is suffering the effects of the hydrological crisis. Qualitatively, the Metropolitan Region of São Paulo includes some of the most impaired aquatic environments. The Cantareira Complex is formed by five reservoirs. It is one of the main water suppliers of the region, which has high water demand and produces intensive environmental impairments. The pollution of aquatic environments by metals and metalloids is a worldwide problem and it is frequently related to the impairments generated in urban and industrialized regions. A problem related with this type of pollution is the fact that metals and metalloids are not metabolized by biota. As consequence, these chemicals have the tendency to accumulate through the time in the environment, especially in the sediments. Therefore, the pollution of the sediments can favor water pollution and the contamination of organisms living in aquatic ecosystems. In the present research, data referring to water and sediment quality from three reservoirs from Cantareira Complex (Jaguari and Jacareí were considered as a whole) were obtained. Po... (Complete abstract click electronic access below)<br>Doutor
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Devor, Devin Patrick. "Effects of Hyperoxia on Thermal Tolerance and Indicators of Hypoxic Stress in Antarctic Fishes That Differ in Expression of Oxygen-Binding Proteins." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1362666619.
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Fernandes, Gerson Eli. "Cobertura florestal ou função ecológica: o dilema da restauração na bacia do Rio Sorocaba." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8531.
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Previous issue date: 2016-09-21<br>Não recebi financiamento<br>The study aimed to evaluate restored areas implemented in the basin of the Sorocaba River and Middle Tiete based on terms of commitments to environmental restoration and conduct adjustment terms. We selected two to three projects in each sub-basin to those with the presence of restoration, certified by the consent of the owner. In each restoration, we evaluated attributes of species diversity and functions, control and management, soil protection and nutrient cycling. The restored areas restoration presented 17 ± 10 species, under the condition established by law, mortality was high, around 40% with an average of 1090 individuals/ha. Croton floribundus, Schinus terebinthifolius, Guazuma ulmifolia, Inga vera, Citharexylum myrianthum, Cordia sellowiana represented 31.7% of species planted and together with Enterolobium contortisiliquum, colubrina Anadenanthera, C. urucurana, Ceiba speciosa, Eugenia uniflora, Lithraea molleoides, Psidium guajava, Triplaris americana, Erythrina speciosa represented 52.8% of the planted individuals. The restoration were in critical situation and, although species richness is according to legal requirements, we observed the concentration on few common and frequent species in general pioneers. Regardless of age, the studied areas did not restore the structural and physical aspects of the forest, and were not efficient in the establishment of ecological processes, highlighting the need to review the procedures adopted in the legal and technical mechanisms of restoration in the region.<br>O estudo teve por objetivo avaliar projetos de restauração de áreas degradadas implantados na bacia dos Rios Sorocaba e Médio Tietê realizados a partir de termos de compromissos de restauração ambiental e termo de ajustamento de conduta. Foram selecionados dois a três projetos em cada sub-bacia entre os que apresentavam presença da restauração, atestada pela anuência do proprietário. Em cada restauração foram avaliados os atributos da diversidade de espécies e de funções, controle e manejo, proteção do solo e ciclagem de nutrientes. As áreas em restauração apresentaram 17±10 espécies, abaixo da condição estabelecida pela legislação, com alta mortalidade, em torno de 40% e média de 1090 indivíduos/ha. Das espécies, Croton floribundus, Schinus terebinthifolius, Guazuma ulmifolia, Inga vera, Citharexylum myrianthum, Cordia sellowiana, representaram 31,7% dos indivíduos e, juntamente com Enterolobium contortisiliquum, Anadenanthera colubrina, Croton urucurana, Ceiba speciosa, Eugenia uniflora, Lithraea molleoides, Psidium guajava, Triplaris americana, Erythrina speciosa somaram 52,8% dos indivíduos plantados. Os projetos de restauração foram considerados em situação crítica e, embora apresentem riqueza dentro do recomendado, concentraram-se em poucas de espécies mais comuns e frequentes, em geral pioneiras. Independentemente da idade, as áreas estudadas não restauraram os aspectos estruturais e físicos da floresta, e não foram eficientes no estabelecimento dos processos ecológicos, evidenciando a necessidade de se rever os procedimentos adotados nos mecanismos legais e técnicos da restauração na região.
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Williams, James Michael. "Assessment of anti-neoplastic activity in cancerous and non-cancerous cells using nuclear growth indicators." CSUSB ScholarWorks, 1997. https://scholarworks.lib.csusb.edu/etd-project/1321.
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Velonis, Heather Kelly. "Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus)." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/4021.
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Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately predict parturition can have a direct impact on elephant welfare. Elephants in captivity often require significant preparation and management throughout the birthing process, and complications during labor and delivery can necessitate immediate intervention, including stillbirth, protracted labor, maternal aggression towards a newborn calf, and dystocia. Being able to predict when parturition will commence can ensure appropriate staff is available and adequate monitoring is performed. Routine endocrine sampling can be used to predict parturition in Asian elephants, with a drop in progesterone (P4) to baseline levels signaling parturition in 2-5 days. However, we determined this method is not without limitations, and it is not used in all institutions that house elephants. As changes in hormones regulate and alter behaviors, we investigated behavioral indicators as an additional management tool for predicting parturition, a time of drastic hormone changes. We conducted a study of five pregnancies in Asian elephants at the Oregon Zoo, U.S.A, and Taronga Zoo, Australia, between 2008 and 2012.
In Chapter 2, I evaluated progesterone (P4) and cortisol levels across three time periods: Baseline; Pre, (the week preceding the drop in P4); and Post, (the period after the P4 drop). Levels of P4 were significantly lower, and levels of cortisol were significantly higher in the days just prior to parturition. I found considerable intra- and inter-individual variation in both endocrine profiles, which can make endocrine assessments difficult to interpret in real time.
In Chapter 3, I investigated whether behaviors in the preparturition period could be predictive of impending parturition in the Asian elephant. ANOVA results indicated a significant difference in the amount of time that elephants spent walking backwards across three time periods (F(2) = 3.723, p = 0.033), with the behavior increasing as parturition approached. These results were supported by a non-parametric Kruskal- Wallis. Using a generalized linear mixed model (GLMM), I found that as P4 levels decrease, walking backwards behavior significantly increases.
In Chapter 4, I evaluated investigative trunk behaviors, or "trunk checks", directed towards the temporal gland near the ear, mammary glands, vulva and anus of the pregnant dam. Investigative behaviors included both self-directed behaviors and those sent from herd mates towards the pregnant dam. Self-directed behaviors are most likely associated with physical changes in the pregnant dam, such as using the trunk to pull on swollen teats. Other-directed behaviors may stem from chemo-sensory signaling or other types of communication between herd mates, such as detecting changes in progesterone or cortisol. I ran GLMM and found that four trunk-check behaviors varied significantly with P4 and/or cortisol profiles. These were: self-checks of mammary glands increased with decreasing P4 levels; herd-mate-checks of mammary glands increased with decreasing P4 levels; self-checks of vulva increased with decreasing P4 levels and increasing cortisol levels; herd-mate-checks of anus increased with increasing cortisol levels.
In Chapter 5, I evaluated activity budget behaviors in the pregnant elephants. Generalized comparisons were made to published activity budgets of typical captive Asian elephants. I report that activity budgets are within the range of normal activity, though I note a high level of inter-individual variation. In addition, I compared two sampling techniques, including one-zero and instantaneous sampling, that were used for activity budget data collection. I discuss the different results obtained by each sampling technique.
These results are a very promising indication that behaviors, including walking backwards and multiple trunk-check behaviors, are changing over time or with parturition-related hormone profiles. We recommend that keepers, veterinary staff, and other observers that are familiar with the regular behavioral repertoire of a pregnant female should pay close attention to these highlighted behaviors. Keeping track of these behaviors, especially in conjunction with P4 and cortisol tracking, can help staff refine existing windows of expected parturition.
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Bastos, Joani Cristina Húngaro Aires da Gama [UNESP]. "Avaliação da sensibilidade de organismos aquáticos e terrestres ao triclopyr." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/136029.
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000858310.pdf: 845115 bytes, checksum: 5ec5166e1b27f0663340b13817b13b43 (MD5)<br>O uso inadequado de herbicidas como o triclopyr pode gerar resíduos no solo e na água que podem colocar em risco o equilíbrio do meio ambiente. Para compreender os efeitos deste herbicida no meio ambiente, o presente tem como objetivo classificar o triclopyr pela sua toxicidade aguda para cinco espécies aquáticas, selecionar espécies não alvo para o monitoramento ambiental desta molécula com base em três classificações de risco de intoxicação ambiental, selecionar plantas indicadores da presença de resíduos do herbicida no solo e se ele é seguro para ser utilizado no controle de macrófitas. Para a toxicidade aguda de organismos não alvos, foram realizados ensaios de toxicidade aguda com o mato grosso (Hypessobrycon eques), caramujo (Pomacea canaliculata), Azolla caroliniana, Lemna minor e Daphnia magna. O risco de intoxicação ambiental foi classificado de acordo com três classificações, que foi calculado pela divisão entre o valor da concentração ambiental estimada (mg L-1) e pela CL50 ou CE50 (mg L -1) para cada organismo não alvo. Para a sua presença no solo foram realizados ensaios em sala aclimatada com as espécies pepino (Cucumis sativus), tomate (Solanum lycopersicum) e rabanete (Raphanus sativus) nas concentrações de 0,0; 0,5 1,0; 2,5; 5,0 e 7,5 mg L-1, a avaliação da fitotoxicidade das plantas foram realizadas no 3º, 7º, 11º e 14º dia após aplicação e no 14º dia foi realizada a avaliação da altura das plantas e matéria seca total. A avaliação da eficácia do triclopyr foi realizada em casa de vegetação, as doses utilizadas foram 0,0; 0,5; 1,0; 2,0; 3,0 e 4,0 L ha-1, as espécies utilizadas foram Myriofyllum aquaticum, Nymphoide indica e Limnobium laevigatum. A Cl50 e CE50, 48h para o triclopyr foi de 0,61 e 0,62 mg L-1 para H. eques e D. magna respectivamente, para P. canaliculata, A. caroliniana e L. minor a CE50, 7 dias foram de 4,67; 10,52 e 6,95 mg L-1, respectivamente...<br>Improper use of herbicides such as triclopyr may generate residues in soil and water that can endanger the balance of the environment. To understand the effects of this herbicide in the environment, this aims to classify the triclopyr for its acute toxicity to five aquatic species, select non-target species for the environmental monitoring of this molecule based on three environmental poisoning risk ratings, select plants indicators of the presence of herbicide residues in the soil and if it is safe to be used for controlling weeds. For acute toxicity to non-target organisms were conducted acute toxicity tests with the Mato Grosso (Hyphessobycon eques), snail (Pomacea canaliculata), Azolla caroliniana, Lemna minor and Daphnia magna. The risk of environmental poisoning has been classified according to three classifications, which was calculated by dividing the value of the estimated environmental concentration (mg L-1) and the CL50 or CE50 (mg L -1) for each non-target organism. For their presence in the soil tests were conducted at room acclimatized to the species Cucumber (Cucumis sativus), tomato (Solanum lycopersicum) and radish (Raphanus sativus) at concentrations of 0.0; 0.5 1.0; 2.5; 5.0 and 7.5 mg L-1, the evaluation of the phytotoxicity of the plants were carried out on the 3rd, 7th, 11th and 14th day after application and after 14 days an assessment was made of plant height and total dry matter. Assessing the effectiveness of triclopyr was conducted in a greenhouse, the doses used were 0.0; 0.5; 1.0; 2.0; 3.0 and 4.0 L ha-1, and species used were Myriofyllum aquaticum, Nymphoide indica and Limnobium laevigatum. The CL50 and CE50 for 48h triclopyr was 0.61 and 0.62 mg L-1 for H. eques and D. magna respectively, P. canaliculata, A. caroliniana and L. minor CE50, 7 days were 4.67; 10.52 and 6.95 mg L-1, respectively, ranking as moderately toxic to L. minor, A. caroliniana and P. canaliculata as high or highly toxic to H. eques ...
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Bastos, Joani Cristina Húngaro Aires da Gama. "Avaliação da sensibilidade de organismos aquáticos e terrestres ao triclopyr /." Jaboticabal, 2015. http://hdl.handle.net/11449/136029.
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Orientador: Dagoberto Martins<br>Coorientador: Robinson Antonio Pitelli<br>Banca: Silvano Bianco<br>Banca: Fernando Tadeu de Carvalho<br>Banca: Ricardo Victória Filho<br>Banca: Marcos Antonio Kuva<br>Resumo: O uso inadequado de herbicidas como o triclopyr pode gerar resíduos no solo e na água que podem colocar em risco o equilíbrio do meio ambiente. Para compreender os efeitos deste herbicida no meio ambiente, o presente tem como objetivo classificar o triclopyr pela sua toxicidade aguda para cinco espécies aquáticas, selecionar espécies não alvo para o monitoramento ambiental desta molécula com base em três classificações de risco de intoxicação ambiental, selecionar plantas indicadores da presença de resíduos do herbicida no solo e se ele é seguro para ser utilizado no controle de macrófitas. Para a toxicidade aguda de organismos não alvos, foram realizados ensaios de toxicidade aguda com o mato grosso (Hypessobrycon eques), caramujo (Pomacea canaliculata), Azolla caroliniana, Lemna minor e Daphnia magna. O risco de intoxicação ambiental foi classificado de acordo com três classificações, que foi calculado pela divisão entre o valor da concentração ambiental estimada (mg L-1) e pela CL50 ou CE50 (mg L -1) para cada organismo não alvo. Para a sua presença no solo foram realizados ensaios em sala aclimatada com as espécies pepino (Cucumis sativus), tomate (Solanum lycopersicum) e rabanete (Raphanus sativus) nas concentrações de 0,0; 0,5 1,0; 2,5; 5,0 e 7,5 mg L-1, a avaliação da fitotoxicidade das plantas foram realizadas no 3º, 7º, 11º e 14º dia após aplicação e no 14º dia foi realizada a avaliação da altura das plantas e matéria seca total. A avaliação da eficácia do triclopyr foi realizada em casa de vegetação, as doses utilizadas foram 0,0; 0,5; 1,0; 2,0; 3,0 e 4,0 L ha-1, as espécies utilizadas foram Myriofyllum aquaticum, Nymphoide indica e Limnobium laevigatum. A Cl50 e CE50, 48h para o triclopyr foi de 0,61 e 0,62 mg L-1 para H. eques e D. magna respectivamente, para P. canaliculata, A. caroliniana e L. minor a CE50, 7 dias foram de 4,67; 10,52 e 6,95 mg L-1, respectivamente...<br>Abstract: Improper use of herbicides such as triclopyr may generate residues in soil and water that can endanger the balance of the environment. To understand the effects of this herbicide in the environment, this aims to classify the triclopyr for its acute toxicity to five aquatic species, select non-target species for the environmental monitoring of this molecule based on three environmental poisoning risk ratings, select plants indicators of the presence of herbicide residues in the soil and if it is safe to be used for controlling weeds. For acute toxicity to non-target organisms were conducted acute toxicity tests with the Mato Grosso (Hyphessobycon eques), snail (Pomacea canaliculata), Azolla caroliniana, Lemna minor and Daphnia magna. The risk of environmental poisoning has been classified according to three classifications, which was calculated by dividing the value of the estimated environmental concentration (mg L-1) and the CL50 or CE50 (mg L -1) for each non-target organism. For their presence in the soil tests were conducted at room acclimatized to the species Cucumber (Cucumis sativus), tomato (Solanum lycopersicum) and radish (Raphanus sativus) at concentrations of 0.0; 0.5 1.0; 2.5; 5.0 and 7.5 mg L-1, the evaluation of the phytotoxicity of the plants were carried out on the 3rd, 7th, 11th and 14th day after application and after 14 days an assessment was made of plant height and total dry matter. Assessing the effectiveness of triclopyr was conducted in a greenhouse, the doses used were 0.0; 0.5; 1.0; 2.0; 3.0 and 4.0 L ha-1, and species used were Myriofyllum aquaticum, Nymphoide indica and Limnobium laevigatum. The CL50 and CE50 for 48h triclopyr was 0.61 and 0.62 mg L-1 for H. eques and D. magna respectively, P. canaliculata, A. caroliniana and L. minor CE50, 7 days were 4.67; 10.52 and 6.95 mg L-1, respectively, ranking as moderately toxic to L. minor, A. caroliniana and P. canaliculata as high or highly toxic to H. eques ...<br>Doutor
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Carpenter, Kurt Davis. "Indicators of Nutrient Limited Plankton Growth in Lakes Near Mount Saint Helens, Washington." PDXScholar, 1994. https://pdxscholar.library.pdx.edu/open_access_etds/4874.
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Several lakes located in the blast zone of the 1980 eruption of Mount St. Helens were studied to determine if the plankton in the lakes were limited in their growth by nitrogen or phosphorus availability. Long term nutrient enrichment experiments were performed on lake water from five lakes and measures of chlorophyll-a, carbon fixation, and nutrient uptake were used to evaluate the extent of limitation. Nutrient concentrations, ratios, and uptake from 14 lakes provided additional evidence for limitation by nitrogen and/or phosphorus. The physical, chemical, and biological characteristics of the lakes were also examined to monitor the return of these lakes to pre-eruption conditions. Lakes heavily impacted by the 1980 eruption (Ryan, Fawn, and Hanaford Lakes) and newly formed Castle Lake produced positive responses to nitrogen additions, reflecting the continuing importance of nitrogen in these lakes. Evidence for colimitation by phosphorous was apparent in some of the lakes. Venus Lake, located near the fringe of the blast zone received less organic debris and responded only with phosphorus additions. Evaluations of nutrient depletion from the photic zones of these lakes during the growing season supported the results from the bioassays. Two measures of growth (chlorophyll-a and carbon fixation) often responded differently to enrichment, suggesting active algal and bacterial communities in some of the lakes. Qualitative measures of alkaline phosphatase activity normalized to chlorophyll-a indicated that those lakes which contained the highest dissolved organic carbon and bacterial counts following the eruption had higher alkaline phosphatase activities than less impacted lakes, suggesting bacterial enzyme production. Alkaline phosphatase activity confirmed that phosphorus limitation was more severe in lakes having less soluble reactive phosphorus. Most of the lakes appear to be similar to other Cascade Mountain lakes, although many have reduced dissolved oxygen concentrations in the bottom waters during stratification. Incomplete mixing of these lakes during periods of circulation may regulate the decomposition of the organic material and hence, full recovery of these lakes.
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Beazley, Karen. "A focal-species approach to biodiversity management in Nova Scotia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0026/NQ36569.pdf.
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