Bibliografías temáticas / Effect of habitat modification on / Artículos de revistas

Siga este enlace para ver otros tipos de publicaciones sobre el tema: Effect of habitat modification on.

Artículos de revistas sobre el tema "Effect of habitat modification on"

Autor: Grafiati

Publicado: 4 de junio de 2021

Última modificación: 3 de marzo de 2023

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 50 mejores artículos de revistas para su investigación sobre el tema "Effect of habitat modification on".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore artículos de revistas sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

Setiawan, Kuncoro Teguh, Nana Suwargana, Devica Natalia Br. Ginting, Masita Dwi Mandini Manessa, Nanin Anggraini, Syifa Wismayati Adawiah, Atriyon Julzarika, Surahman Surahman, Syamsu Rosid, and Agustinus Harsono Supardjo. "BATHYMETRY EXTRACTION FROM SPOT 7 SATELLITE IMAGERY USING RANDOM FOREST METHODS." International Journal of Remote Sensing and Earth Sciences (IJReSES) 16, no. 1 (October 23, 2019): 23. http://dx.doi.org/10.30536/j.ijreses.2019.v16.a3085.

Texto completo

Resumen

The scope of this research is the application of the random forest method to SPOT 7 data to produce bathymetry information for shallow waters in Indonesia. The study aimed to analyze the effect of base objects in shallow marine habitats on estimating bathymetry from SPOT 7 satellite imagery. SPOT 7 satellite imagery of the shallow sea waters of Gili Matra, West Nusa Tenggara Province was used in this research. The estimation of bathymetry was carried out using two in-situ depth-data modifications, in the form of a random forest algorithm used both without and with benthic habitats (coral reefs, seagrass, macroalgae, and substrates). For bathymetry estimation from SPOT 7 data, the first modification (without benthic habitats) resulted in a 90.2% coefficient of determination (R2) and 1.57 RMSE, while the second modification (with benthic habitats) resulted in an 85.3% coefficient of determination (R2) and 2.48 RMSE. This research showed that the first modification achieved slightly better results than the second modification; thus, the benthic habitat did not significantly influence bathymetry estimation from SPOT 7 imagery.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Noureen, Nadia, Mubashar Hussain, Muhammad Faheem Malik, Muhammad Umar, Zaheer Abbas, and Saira Munaward. "Habitat Types Effect on Diversity, Distribution and Abundance of Dung Beetles." Biological Sciences - PJSIR 64, no. 3 (October 4, 2021): 217–24. http://dx.doi.org/10.52763/pjsir.biol.sci.64.3.2021.217.224.

Texto completo

Resumen

Dung beetles are ecologically important taxa to study the assessment of habitat modification and disturbance across the globe. This study was aimed to explore community composition, species richness and abundance of dung beetles in response to Gujrat, Punjab, Pakistan. Dung beetle assemblage were sampled from four habitat (natural rangeland, cropland, roadside and housing colonies) during 2014-2016 by placing pitfall traps baited with cattle dung. A total number of 540 specimens representing 17 species belonging to seven genera and four tribes were collected. We calculated species relative abundance in natural habitat (34.8%), cropland habitat (40.4%) and in road side areas (25.2%) was recorded, whereas no specimens were recorded in urban areas. Aphodius contaminatus (42.96%) was the most abundant species followed by Onitis castaneous (26.29%) and Onitis singhalensis (20.74%). Tunnellers (50.58%) and dwellers (49.01%) were dominant in all habitats, whereas rollers were least abundant (1.37%). The values of Shannon-Wiener (H) diversity and evenness (E) showed variations among different habitats i.e. natural habitat (H=1.20; E=0.55), cropland habitat (H=1.41, E=0.32) and roads-side (H=0.80, E=0.37). The study showed that cropland served as a major habitat for dung beetles due to its uniformity and close association with mammalian fauna. The results emphasized that natural habitats within the agro-ecosystem have become isolated and fragmented habitat with lesser stability and low resources thus resulting into less diverse habitat. Roadside areas are in close proximity with cropland and act as corridors for efficient species flow within ecosystem due to cattle movement through these areas.  

Los estilos APA, Harvard, Vancouver, ISO, etc.

Lynn, Scott G., and Christian Lindle. "The effect of anthropogenic habitat modification on habitat use byAfrana angolensisalong the dodwe river, Tanzania." African Journal of Herpetology 51, no. 1 (June 2002): 69–73. http://dx.doi.org/10.1080/21564574.2002.9635463.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Fontúrbel, Francisco E., and Maureen M. Murúa. "Microevolutionary Effects of Habitat Fragmentation on Plant-Animal Interactions." Advances in Ecology 2014 (August 25, 2014): 1–7. http://dx.doi.org/10.1155/2014/379267.

Texto completo

Resumen

Plant-animal interactions are a key component for biodiversity maintenance, but they are currently threatened by human activities. Habitat fragmentation might alter ecological interactions due to demographic changes, spatial discontinuities, and edge effects. Also, there are less evident effects of habitat fragmentation that potentially alter selective forces and compromise the fitness of the interacting species. Changes in the mutualistic and antagonistic interactions in fragmented habitats could significantly influence the plant reproductive output and the fauna assemblage associated with. Fragmented habitats may trigger contemporary evolution processes and open new evolutionary opportunities. Interacting parties with a diffuse and asymmetric relationship are less susceptible to local extinction but more prone to evolve towards new interactions or autonomy. However, highly specialized mutualisms are likely to disappear. On the other hand, ecological interactions may mutually modulate their response in fragmented habitats, especially when antagonistic interactions disrupt mutualistic ones. Ecoevolutionary issues of habitat fragmentation have been little explored, but the empiric evidence available suggests that the complex modification of ecological interactions in fragmented habitats might lead to nonanalogous communities on the long term.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Wen, C. K. C., M. S. Pratchett, K. T. Shao, K. P. Kan, and B. K. K. Chan. "Effects of habitat modification on coastal fish assemblages." Journal of Fish Biology 77, no. 7 (October 26, 2010): 1674–87. http://dx.doi.org/10.1111/j.1095-8649.2010.02809.x.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

MAIROTA, PAOLA, VINCENZO LERONNI, WEIMIN XI, DAVID J. MLADENOFF, and HARINI NAGENDRA. "Using spatial simulations of habitat modification for adaptive management of protected areas: Mediterranean grassland modification by woody plant encroachment." Environmental Conservation 41, no. 2 (November 15, 2013): 144–56. http://dx.doi.org/10.1017/s037689291300043x.

Texto completo

Resumen

SUMMARYSpatial simulation may be used to model the potential effects of current biodiversity approaches on future habitat modification under differing climate change scenarios. To illustrate the approach, spatial simulation models, including landscape-level forest dynamics, were developed for a semi-natural grassland of conservation concern in a southern Italian protected area, which was exposed to woody vegetation encroachment. A forest landscape dynamics simulator (LANDIS-II) under conditions of climate change, current fire and alternative management regimes was used to develop scenario maps. Landscape pattern metrics provided data on fragmentation and habitat quality degradation, and quantified the spatial spread of different tree species within grassland habitats. The models indicated that approximately one-third of the grassland area would be impacted by loss, fragmentation and degradation in the next 150 years. Differing forest management regimes appear to influence the type of encroaching species and the density of encroaching vegetation. Habitat modifications are likely to affect species distribution and interactions, as well as local ecosystem functioning, leading to changes in estimated conservation value. A site-scale conservation strategy based on feasible integrated fire and forest management options is proposed, considering the debate on the effectiveness of protected areas for the conservation of ecosystem services in a changing climate. This needs to be tested through further modelling and scenario analysis, which would benefit from the enhancement of current modelling capabilities of LANDIS-II and from combination with remote sensing technologies, to provide early signals of environmental shifts both within and outside protected areas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Eleftheriou, Andreas, and Angela D. Luis. "Investigating the effect of habitat modification on chronic stress in deer mice: a preliminary study." Wildlife Rehabilitation Bulletin 37, no. 1 (November 29, 2021): 10–15. http://dx.doi.org/10.53607/wrb.v37.110.

Texto completo

Resumen

Anthropogenic habitat modification can lead to chronic stress in wildlife. This can result in immunosuppression and higher disease prevalence. Chronically stressed individuals typically have elevated baseline GCs and decreased body condition. GCs are called FGMs when excreted in feces and can be used to noninvasively evaluate stress in free-ranging wildlife. In the deer mouse (Peromyscus maniculatus)–SNV system, SNV prevalence is higher in deer mice at peridomestic settings, which are human-modified habitats. This is problematic because SNV causes a fatal disease in humans, and thus the higher SNV prevalence may lead to higher risk of infection for humans. In our study, we hypothesized that SNV prevalence would be higher in deer mice at human-modified habitats due to chronic stress. To test our hypothesis, we compared two stress measures (i.e., baseline FGMs and body condition scores) in deer mice from one peridomestic and one sylvan grid over 2 months. Captured deer mice were tagged, weighed, sexed and sampled for feces and blood and were evaluated for reproductive status and body condition before release. Blood samples were analysed for SNV antibodies, and fecal samples were evaluated for FGMs. We found higher deer mouse numbers at the sylvan grid. There were no differences in baseline FGM levels between peridomestic and sylvan populations. However, peridomestic deer mice had overall lower body condition. Given the low SNV prevalence across both grids, we were unable to examine potential correlations between SNV prevalence and chronic stress. Regardless, we conclude that deer mice at human-modified habitats may not be chronically stressed, which may suggest that higher SNV prevalence at peridomestic settings may not be the result of chronic stress. Although we did find that peridomestic deer mice had lower body condition, this may not have been related to chronic stress because there were no differences in baseline FGMs. Longer studies with more site replication are needed to validate and expand on our findings. Our preliminary study adds to the existing body of knowledge that examines relationships between stress physiology and disease prevalence in human-modified environments.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Wang, Min, and David E. Lincoln. "Effects of light intensity and artificial wounding on monoterpene production in Myrica cerifera from two different ecological habitats." Canadian Journal of Botany 82, no. 10 (October 1, 2004): 1501–8. http://dx.doi.org/10.1139/b04-107.

Texto completo

Resumen

The contributions of multiple factors to plant defense and herbivory in different habitats has received limited study. This study examines the contributions of genotypic differentiation and modification by physical factors to chemical defense and herbivory of Myrica cerifera L. in contrasting habitats. The constitutive leaf monoterpene content of M. cerifera was higher in a sunny habitat than in an adjacent shady habitat at a southeastern USA coastal site. Leaf area loss was higher in the shady habitat than in the sunny habitat. A significant negative correlation of monoterpene content and leaf area loss suggests that monoterpenes may play toxic or deterrent roles in these plants. When plants from the two habitats were grown under uniform greenhouse conditions, the contents and compositions of leaf monoterpenes were not significantly different, implying that two ecotypes were not involved. The plants treated in high light intensity had significantly higher monoterpene content, higher growth rate, and denser glandular trichomes than the plants treated in low light intensity. Artificial wounding induced a significant increase of monoterpene production. However, the wounding responses of the plants from the two habitats were not different, nor did irradiance modify the response.Key words: ecotype, herbivory, light intensity, monoterpenes, wounding induction, Myrica cerifera.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Horváth, G. F., Barbara Horváth, Nikolett Sali, and R. Herczeg. "Community-level response to different human disturbances and land use of small mammals in two marshland habitat patches in Hungary." Archives of Biological Sciences 64, no. 2 (2012): 613–28. http://dx.doi.org/10.2298/abs1202613h.

Texto completo

Resumen

Marshlands are important ecosystems that provide valuable habitats for wildlife communities. We investigated the small mammal community-level response to different human disturbances and land use in the Kis-Balaton Landscape Protection Area, which is an endangered marshland ecosystem of Hungary. Land use, conservation management and other human disturbances (burning, mowing) together with unfavorable weather conditions have caused the degradation of the original homogeneous sedgy marshland on both sampled areas. We measured the species turnover between the different periods separated by the habitat changes. Our results suggest that populations of the habitat-specialist species of marshland areas (e.g. endangered Hungarian subspecies of root vole) are sensitive to the negative effects of environment and human disturbances. The combined effect of human disturbances and the stochastic processes of the environment can cause the disappearance and substitution of character species stabilizing the communities, which in turn leads to the modification of species composition and structure of small mammal assemblages.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Angoh, Siow Yan Jennifer, Joanna Freeland, James Paterson, Prabha Amali Rupasinghe, and Christina M. Davy. "Effects of invasive wetland macrophytes on habitat selection and movement by freshwater turtles." Biological Invasions 23, no. 7 (April 11, 2021): 2271–88. http://dx.doi.org/10.1007/s10530-021-02505-8.

Texto completo

Resumen

AbstractInvasive species can significantly impact native wildlife by structurally altering habitats and access to resources. Understanding how native species respond to habitat modification by invasive species can inform effective habitat restoration, avoiding inadvertent harm to species at risk. The invasive graminoids Phragmites australis australis (hereafter Phragmites) and Typha × glauca are increasingly dominating Nearctic wetlands, often outcompeting native vegetation. Previous research suggests that turtles may avoid invasive Phragmites when moving through their home ranges, but the mechanisms driving avoidance are unclear. We tested two hypotheses that could explain avoidance of invaded habitat: (1) that stands of invasive macrophytes (Phragmites and Typha x glauca) impede movement, and (2) that they provide inadequate thermal conditions for turtles. We quantified active-season movements of E. blandingii (n = 14, 1328 relocations) and spotted turtles (Clemmys guttata; n = 12, 2295 relocations) in a coastal wetland in the Laurentian Great Lakes. Neither hypothesis was supported by the data. Phragmites and mixed-species Typha stands occurred within the home ranges of mature, active E. blandingii and C. guttata, and were used similarly to most other available habitats, regardless of macrophyte stem density. Turtles using stands of invasive macrophytes did not experience restricted movements or cooler shell temperatures compared to other wetland habitat types. Control of invasive macrophytes can restore habitat heterogeneity and benefit native wetland species. However, such restoration work should be informed by the presence of at-risk turtles, as heavy machinery used for control or removal may injure turtles that use these stands as habitat.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Rofidah, Erna, Siti Arofah, and Indah Trisnawati Dwi Tjahjaningrum. "THE EFFECT OF HABITAT MODIFICATION ON PADDY VARIETY IR 64 FIELD WITH TRAP CROP APPLICATION USING LEMON GRASS (Andropogon nardus ) AND WITHOUT TRAP CROP APPLICATION TOWARDS THE COMPOTITION, ABUNDANCE, AND DIVERSITY OF ARTHROPODS." KnE Life Sciences 2, no. 1 (September 20, 2015): 605. http://dx.doi.org/10.18502/kls.v2i1.226.

Texto completo

Resumen

The trap crop technique relies on the attraction of insect pests to plantings other than the main crop. Application using of lemon grass for Habitat modification on paddy field can alter species composition and community structure including Arthropods from insect groups. The lemon grass was planted 20 day before main crop (paddy variety IR 64). This study was conducted in Pasuruan, East Java. Samples were taken using sweep net on vegetative paddy phase, generative paddy phase and ripening paddy phase. Sampling periods from Desember 2012 to March 2013. Each sample was sorted and identified to the family and morphospecies or species. Samples are identified in Zoological laboratory on department of biology, ITS. Study on Arthropoda diversity at different habitats by comparing the species richness is useful for determining ecological indicators at each habitat. The arthropods caught were then classified into some classes: pest (herbivore), natural enemy (parasitoid and predator), and other arthropods. After that, the Species Diversity Index was determined using its Shannon-Wiener Index (H’), Evenness (e), and Species Similarity Index (IS). The compotition of arthropods were classes from herbivore, predator, parasitoid and detritivore. The sum of H’ is higher on paddy field with trap crop application than paddy field without trap crop application. Indicate that a stable relationship could be maintained between rice insect pests and their arthropod natural enemies. Keywords : Habitat modification, Trap crop, Arthropods, compotition, abundance, diversity

Los estilos APA, Harvard, Vancouver, ISO, etc.

Patla, Debra, and Charles Peterson. "The Effects of Habitat Modification on a Spotted Frog Population in Yellowstone National Park." UW National Parks Service Research Station Annual Reports 17 (January 1, 1993): 3–13. http://dx.doi.org/10.13001/uwnpsrc.1993.3129.

Texto completo

Resumen

Declines and extinctions of many populations of amphibians have been noted worldwide in recent years (Corn and Fogelman 1984, Beiswenger 1986, McAllister and Leonard 1990, Wake and Morowitz 1990, Wake 1991, Adler 1992). Habitat modifications due to human activities may contribute to many of these declines. Habitat may be destroyed overtly, or it may be fragmented. Fragmentation results in reduced area, a differential loss of important habitat components, and increased isolation of populations (Wyman 1990). The persistence of amphibians in areas where modifications short of total habitat destruction occur depends on the preservation of essential habitat components and landscape connectivity that allows individual animals access to breeding, foraging, and wintering sites (Sinsch 1989). Long-term persistence also may rely on the immigration of individuals from other populations (Pechmann et al. 1991, Sjogren 1991). Our efforts to conserve amphibian species and to establish methods of sustainable resource use depend on our understanding of habitat fragmentation and knowledge of the behavioral and population responses to different types of habitat modifications (Gibbons 1988, Groom and Schumaker 1993). Few studies have addressed these types of questions. Notable exceptions include some studies on the effects of logging (Corn and Bury 1989) and acidification (Wyman and Hawksley-Lescault 1988, Harte and Hoffman 1989, Corn and Vertucci 1992). In Europe, researchers and wildlife conservationists are investigating the impacts of roads on amphibians and attempting to find solutions to fragmentation and mortality effects (Langton 1989), but this concern has not yet received noticeable attention in North America. We lack studies evaluating the relative importance and integration of foraging areas, hibernacula, breeding sites, areas occupied pre- and post-breeding, and dispersal routes connecting these areas. With these kinds of information, researchers and land managers will acquire the ability to better analyze, predict, and mitigate the effects of habitat modifications that are sources of amphibian population declines.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Patla, Debra, and Charles Peterson. "The Effects of Habitat Modification on a Spotted Frog Population in Yellowstone National Park." UW National Parks Service Research Station Annual Reports 18 (January 1, 1994): 135–44. http://dx.doi.org/10.13001/uwnpsrc.1994.3215.

Texto completo

Resumen

Declines and extinctions of many populations of amphibians have been noted worldwide in recent years (Corn and Fogelman 1984, Beiswenger 1986, McAllister and Leonard 1990, Wake and Morowitz 1990, Wake 1991, Adler 1992). Habitat modifications due to human activities may contribute to many of these declines. Habitat may be destroyed overtly, or it may be fragmented. Fragmentation results in reduced area, a differential loss of important habitat components, and increased isolation of populations (Wyman 1990). The persistence of amphibians in areas where modifications short of total habitat destruction depends on the preservation of essential habitat components and landscape connectivity that allows individual animals access to breeding, foraging, and wintering sites (Sinsch 1989). Long-term persistence also may rely on the immigration of individuals from other populations (Pechmann et al. 1991, Sjogren 1991). Although our efforts to conserve amphibian species depend on our understanding of habitat fragmentation and knowledge of the behavioral and population responses to different types of habitat modifications (Gibbons 1988, Groom and Schumaker 1993), few studies have addressed these types of questions for amphibians. Notable exceptions include some studies on the effects of logging (Corn and Bury 1989) and acidification (Wyman and Hawksley-Lescault 1988, Harte and Hoffman 1989, Corn and Vertucci 1992). In Europe, researchers and wildlife conservationists are investigating the impacts of roads on amphibians and attempting to find solutions to fragmentation and mortality effects (Langton 1989), but this concern has not yet received noticeable attention in North America. We lack studies evaluating the relative importance and integration of foraging areas, hibernacula, breeding sites, areas occupied pre- and post-breeding, and dispersal routes connecting these areas. With these kinds of information, researchers and land managers will be better able to analyze, predict, and mitigate the effects of habitat modifications that are sources of amphibian population declines.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Rossi, Tullio, Ivan Nagelkerken, Jennifer C. A. Pistevos, and Sean D. Connell. "Lost at sea: ocean acidification undermines larval fish orientation via altered hearing and marine soundscape modification." Biology Letters 12, no. 1 (January 2016): 20150937. http://dx.doi.org/10.1098/rsbl.2015.0937.

Texto completo

Resumen

The dispersal of larvae and their settlement to suitable habitat is fundamental to the replenishment of marine populations and the communities in which they live. Sound plays an important role in this process because for larvae of various species, it acts as an orientational cue towards suitable settlement habitat. Because marine sounds are largely of biological origin, they not only carry information about the location of potential habitat, but also information about the quality of habitat. While ocean acidification is known to affect a wide range of marine organisms and processes, its effect on marine soundscapes and its reception by navigating oceanic larvae remains unknown. Here, we show that ocean acidification causes a switch in role of present-day soundscapes from attractor to repellent in the auditory preferences in a temperate larval fish. Using natural CO 2 vents as analogues of future ocean conditions, we further reveal that ocean acidification can impact marine soundscapes by profoundly diminishing their biological sound production. An altered soundscape poorer in biological cues indirectly penalizes oceanic larvae at settlement stage because both control and CO 2 -treated fish larvae showed lack of any response to such future soundscapes. These indirect and direct effects of ocean acidification put at risk the complex processes of larval dispersal and settlement.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Sánchez, Cecilia A., Sonia Altizer, and Richard J. Hall. "Landscape-level toxicant exposure mediates infection impacts on wildlife populations." Biology Letters 16, no. 11 (November 2020): 20200559. http://dx.doi.org/10.1098/rsbl.2020.0559.

Texto completo

Resumen

Anthropogenic landscape modification such as urbanization can expose wildlife to toxicants, with profound behavioural and health effects. Toxicant exposure can alter the local transmission of wildlife diseases by reducing survival or altering immune defence. However, predicting the impacts of pathogens on wildlife across their ranges is complicated by heterogeneity in toxicant exposure across the landscape, especially if toxicants alter wildlife movement from toxicant-contaminated to uncontaminated habitats. We developed a mechanistic model to explore how toxicant effects on host health and movement propensity influence range-wide pathogen transmission, and zoonotic exposure risk, as an increasing fraction of the landscape is toxicant-contaminated. When toxicant-contaminated habitat is scarce on the landscape, costs to movement and survival from toxicant exposure can trap infected animals in contaminated habitat and reduce landscape-level transmission. Increasing the proportion of contaminated habitat causes host population declines from combined effects of toxicants and infection. The onset of host declines precedes an increase in the density of infected hosts in contaminated habitat and thus may serve as an early warning of increasing potential for zoonotic spillover in urbanizing landscapes. These results highlight how sublethal effects of toxicants can determine pathogen impacts on wildlife populations that may not manifest until landscape contamination is widespread.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Allen, Daniel C., and Caryn C. Vaughn. "Density-dependent biodiversity effects on physical habitat modification by freshwater bivalves." Ecology 92, no. 5 (May 2011): 1013–19. http://dx.doi.org/10.1890/10-0219.1.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Sewell, Sven R., and Carla P. Catterall. "Bushland modification and styles of urban development: their effects on birds in south-east Queensland." Wildlife Research 25, no. 1 (1998): 41. http://dx.doi.org/10.1071/wr96078.

Texto completo

Resumen

Variation in bird assemblages associated with forest clearing and urbanisation in the greater Brisbane area was assessed by counting birds in sites within six habitat categories: large remnants, small remnants, no- understorey remnants, canopy suburbs (original trees present), planted suburbs, and bare suburbs. Total bird abundance and species richness were generally highest in canopy suburbs. Individual species showed many significant abundance differences among the habitat types, and were classified into three major response categories: bushland species (3 in summer, 13 in winter), tolerant species (13 in summer, 13 in winter), and suburban species (12 in summer, 11 in winter). The commonly proposed notion that urbanisation results in lowered bird species richness and increases in introduced species is broadly consistent with the observed differences between bare suburbs and large remnants. However, it does not adequately describe the situation in the planted and canopy suburbs, where there was high species richness and extremely high abundance of some native species (including noisy miners, lorikeets, friarbirds, and butcherbirds) but low abundance of a majority of the species common in the original habitats (including fantails, wrens, whistlers, and other small insectivores). Retained forest remnants are essential for the latter group. Urban plantings of prolifically flowering native species do not reverse the effects of deforestation, but promote a distinctive group of common native suburban bird species. Origins of the urban bird assemblage are discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Hall, James R., Robin W. Woods, M. de L. Brooke, and Geoff M. Hilton. "Factors affecting the distribution of landbirds on the Falkland Islands." Bird Conservation International 12, no. 2 (June 2001): 151–67. http://dx.doi.org/10.1017/s0959270902002095.

Texto completo

Resumen

A high proportion of island birds are threatened with extinction as a result of their vulnerability to introduced predators, habitat destruction, and fragmentation/isolation effects. In order to conserve island species effectively, it is necessary to disentangle these effects on distribution and abundance. We attempt to do this for the nine native passerines in the Falkland (Malvinas) Islands, using a database of presence/absence on 59 offshore islands in the archipelago, linked to data for each island on mammal presence, habitat modification, and isolation. Falklands native passerines are of considerable conservation importance, comprising one endemic globally threatened species, several endemic subspecies, and several restricted range species. Presence of rats on islands was by far the most important predictor of passerine presence, overriding the effect of habitat modifications. The globally threatened endemic Cobb's Wren Troglodytes cobbi was absent from all islands containing rats. Some species were more likely, and others less likely to occur on islands where tussac Poa flabellata grassland had been destroyed by grazing. The former species were primarily those adapted to dwarf-heath vegetation, and/or that thrive around human settlements. Island size and isolation were important predictors of occurrence for several bird species. The analyses show that, if vegetation restoration in the Falklands is to meet conservation aims, then it should be accompanied by introduced mammal control. Secondly, they indicate that biogeographical effects on bird distribution among islands in the Falklands are important, and need to be considered when assessing the conservation status of species, and when considering conservation action.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Huang, Tingjie, Yan Lu, and Huaixiang Liu. "Effects of Spur Dikes on Water Flow Diversity and Fish Aggregation." Water 11, no. 9 (August 31, 2019): 1822. http://dx.doi.org/10.3390/w11091822.

Texto completo

Resumen

As a typical waterway modification, the spur dike narrows the water cross section, which increases the flow velocity and flushes the riverbed. Meanwhile, it also protects ecological diversity and improves river habitat. Different types of spur dikes could greatly impact the interaction between flow structure and local geomorphology, which in turn affects the evolution of river aquatic habitats. Four different types of spur dikes—including rock-fill, permeable, w-shaped rock-fill, and w-shaped permeable—were evaluated using flume experiments for spur dike hydrodynamics and fish aggregation effects. Based on Shannon’s entropy, an index for calculating water flow diversity is proposed. Additionally, the impact of the different spur dikes on water flow diversity and the relationship between water flow diversity and fish aggregation effects were studied. The water flow diversity index around the spur dike varied from 1.13 to 2.96. The average aggregation rate of test fish around the spur dike was 5% to 28%, and the attraction effect increased with increasing water flow diversity. Furthermore, we plotted the relationship between water flow diversity index and average fish aggregation rate. A fish hydroacoustic study conducted on the Laohutan fish-bone dike in the Dongliu reach of downstream Yangtze River showed that the fish aggregation effect of the permeable spur dike was greater than the rock-fill spur dike. These research results could provide theoretical support for habitat heterogeneity research and ecologically optimal design of spur dikes.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Le, Duong Thi Thuy, Jodi J. L. Rowley, Dao Thi Anh Tran, and Huy Duc Hoang. "The diet of a forest-dependent frog species, Odorrana morafkai (Anura: Ranidae), in relation to habitat disturbance." Amphibia-Reptilia 41, no. 1 (June 12, 2020): 29–41. http://dx.doi.org/10.1163/15685381-20191171.

Texto completo

Resumen

Abstract While deforestation is one of the greatest drivers of biodiversity loss, our understanding of the effects of habitat modification on species is limited. We investigated the diet of a forest-dwelling frog species, Morafka’s frog (Odorrana morafkai), in a highland forest in Vietnam in relation to habitat disturbance, sex and season. We surveyed the species at 45 sites in forest of varying disturbance and examined its diet using stomach flushing, estimating prey availability via trapping. We detected significantly fewer O. morafkai in highly disturbed habitats compared to moderately disturbed or non-disturbed habitats. We revealed that O. morafkai is a dietary generalist, identifying 28 prey types, primarily invertebrates. Prey composition, the number of prey items per stomach and prey volume per stomach did not vary between disturbance levels. Diet did not vary significantly between sexes, except that females had a higher prey volume. Prey composition in the species varied between seasons, with Coleoptera and Orthoptera dominating the diet in the rainy season and Lepidoptera in the dry season. The number of prey items per stomach and prey volume were significantly higher in the rainy season. There was a significant correlation between prey availability and diet composition. The low number of O. morafkai detected in highly disturbed habitats suggests that this habitat may not be optimal for the species, despite having a generalist feeding strategy and presumed high mobility. This study provides a window into the impact of an increasing threat, habitat disturbance, on forest-dependent amphibian species.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Dong, Yuan-Huo, Robert Wahiti Gituru, Jin-Ming Chen, and Qing-Feng Wang. "Effect of Habitat Modification on the Distribution of the Endangered Aquatic FernCeratopteris thalictroides(Parkeriaceae) in China." Journal of Freshwater Ecology 20, no. 4 (December 2005): 689–93. http://dx.doi.org/10.1080/02705060.2005.9664792.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Lawton, J. H., D. E. Bignell, B. Bolton, G. F. Bloemers, P. Eggleton, P. M. Hammond, M. Hodda, et al. "Biodiversity inventories, indicator taxa and effects of habitat modification in tropical forest." Nature 391, no. 6662 (January 1998): 72–76. http://dx.doi.org/10.1038/34166.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

DIDHAM, R., J. TYLIANAKIS, N. GEMMELL, T. RAND, and R. EWERS. "Interactive effects of habitat modification and species invasion on native species decline." Trends in Ecology & Evolution 22, no. 9 (September 2007): 489–96. http://dx.doi.org/10.1016/j.tree.2007.07.001.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Russell, Micah T., Jennifer M. Cartwright, Gail H. Collins, Ryan A. Long, and Jan H. Eitel. "Legacy Effects of Hydrologic Alteration in Playa Wetland Responses to Droughts." Wetlands 40, no. 6 (July 28, 2020): 2011–24. http://dx.doi.org/10.1007/s13157-020-01334-0.

Texto completo

Resumen

AbstractWetland conservation increasingly must account for climate change and legacies of previous land-use practices. Playa wetlands provide critical wildlife habitat, but may be impacted by intensifying droughts and previous hydrologic modifications. To inform playa restoration planning, we asked: (1) what are the trends in playa inundation? (2) what are the factors influencing inundation? (3) how is playa inundation affected by increasingly severe drought? (4) do certain playas provide hydrologic refugia during droughts, and (5) if so, how are refugia patterns related to historical modifications? Using remotely sensed surface-water data, we evaluated a 30-year time series (1985–2015) of inundation for 153 playas of the Great Basin, USA. Inundation likelihood and duration increased with wetter weather conditions and were greater in modified playas. Inundation probability was projected to decrease from 22% under average conditions to 11% under extreme drought, with respective annual inundation decreasing from 1.7 to 0.9 months. Only 4% of playas were inundated for at least 2 months in each of the 5 driest years, suggesting their potential as drought refugia. Refugial playas were larger and more likely to have been modified, possibly because previous land managers selected refugial playas for modification. These inundation patterns can inform efforts to restore wetland functions and to conserve playa habitats as climate conditions change.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Duncan, Sarah I., Ellen P. Robertson, Robert J. Fletcher, and James D. Austin. "Urbanization and Population Genetic Structure of the Panama City crayfish (Procambarus econfinae)." Journal of Heredity 111, no. 2 (November 20, 2019): 204–15. http://dx.doi.org/10.1093/jhered/esz072.

Texto completo

Resumen

Abstract For species with geographically restricted distributions, the impacts of habitat loss and fragmentation on long-term persistence may be particularly pronounced. We examined the genetic structure of Panama City crayfish (PCC), Procambarus econfinae, whose historical distribution is limited to an area approximately 145 km2, largely within the limits of Panama City and eastern Bay County, FL. Currently, PCC occupy approximately 28% of its historical range, with suitable habitat composed of fragmented patches in the highly urbanized western portion of the range and managed plantations in the more contiguous eastern portion of the range. We used 1640 anonymous single-nucleotide polymorphisms to evaluate the effects of anthropogenic habitat modification on the genetic diversity and population structure of 161 PCC sampled from across its known distribution. First, we examined urban habitat patches in the west compared with less-developed habitat patches in the east. Second, we used approximate Bayesian computation to model inferences on the demographic history of eastern and western populations. We found anthropogenic habitat modifications explain the genetic structure of PCC range-wide. Clustering analyses revealed significant genetic structure between and within eastern and western regions. Estimates of divergence between east and west were consistent with urban growth in the mid-20th century. PCC have low genetic diversity and high levels of inbreeding and relatedness, indicating populations are small and isolated. Our results suggest that PCC have been strongly affected by habitat loss and fragmentation and management strategies, including legal protection, translocations, or reintroductions, may be necessary to ensure long-term persistence.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Robinson, Christopher D., Joanne C. Crawford, Lyann Corcoran, Eric M. Schauber, and Clayton K. Nielsen. "Metapopulation viability of swamp rabbits in southern Illinois: potential impacts of habitat change." Journal of Mammalogy 97, no. 1 (October 8, 2015): 68–79. http://dx.doi.org/10.1093/jmammal/gyv154.

Texto completo

Resumen

Abstract Swamp rabbits ( Sylvilagus aquaticus ) in southern Illinois exist as a metapopulation due to fragmentation of the bottomland hardwood forests in which they live. This fragmentation makes their persistence in Illinois uncertain. We used population viability analysis (PVA) to estimate the probability of persistence of the swamp rabbit metapopulation in Illinois, using a habitat suitability map we created and life history parameters drawn from the literature. We varied the parameters used in our PVA from 50% to 150% of the initial value to compare their effects on extinction risk and to direct future management and research. We tested the effects of potential habitat loss and fragmentation by 1) removing patches individually and in groups from the analysis and by 2) adding 60, 120, and 180 m to the edge of all patches. We also tested the potential effect of dispersal corridors by increasing dispersal between connected patches. Under baseline conditions, the model suggests a 0% chance of quasi-extinction (90% metapopulation decline) of swamp rabbits within 25 (or even 50) years. Changes in fecundity values and the effects of catastrophic flooding had the greatest effect on extinction risk, and changes in no other parameter yielded any appreciable impact. Removing the largest patches from the population increased the 25-year risk of extinction to 4%, whereas any other modifications to the habitat did not change the extinction risk. We suggest that managers focus on sustaining habitat quality, particularly upland habitats adjacent to occupied bottomland hardwood forests to improve the likelihood of swamp rabbit persistence in Illinois.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Sitko, Krzysztof, Magdalena Opała-Owczarek, Gabriela Jemioła, Żaneta Gieroń, Michał Szopiński, Piotr Owczarek, Małgorzata Rudnicka, and Eugeniusz Małkowski. "Effect of Drought and Heavy Metal Contamination on Growth and Photosynthesis of Silver Birch Trees Growing on Post-Industrial Heaps." Cells 11, no. 1 (December 24, 2021): 53. http://dx.doi.org/10.3390/cells11010053.

Texto completo

Resumen

Silver birch trees (Betula pendula Roth) are a pioneering species in post-industrial habitats, and have been associated with an expansive breeding strategy and low habitat requirements. We conducted ecophysiological and dendroclimatological studies to check whether there are any features of which the modification enables birch trees to colonise extreme habitats successfully. We characterised the efficiency of the photosynthetic apparatus, the gas exchange, the content of pigments in leaves, and the growth (leaf thickness and tree-ring width) of birch trees on a post-coal mine heap, a post-smelter heap, and a reference site. Birch growth was limited mainly by temperature and water availability during summer, and the leaves of the birch growing on post-industrial heaps were significantly thicker than the reference leaves. Moreover, birch trees growing on heaps were characterised by a significantly higher content of flavonols and anthocyanins in leaves and higher non-photochemical quenching. In addition, birches growing on the post-coal mine heap accumulated a concentration of Mn in their leaves, which is highly toxic for most plant species. Increasing the thickness of leaves, and the content of flavonols and anthocyanins, as well as efficient non-photochemical quenching seem to be important features that improve the colonization of extreme habitats by birches.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Baker, Jack, Ross L. Goldingay, and Robert J. Whelan. "Powerline easements through forests: a case study of impacts on avifauna." Pacific Conservation Biology 4, no. 1 (1998): 79. http://dx.doi.org/10.1071/pc980079.

Texto completo

Resumen

Powerline easements are typically a strip cleared of trees and tall vegetation to a width of approximately 50 m. They may affect avifauna by modification and fragmentation of forest habitat. We investigated the responses of the bird community to easements at three sites in southeastern Australia using 25 m radius point-counts spaced at 50 m intervals from the easement to 300 m inside the forest. The easements caused an absolute loss of habitat for forest avifauna, with abundance and species richness at the easement less than 20% of the forest values. Four species of easement opportunist and one easement specialist provided evidence that the easement represented a new type of habitat for avifauna. A barrier effect of fragmentation may occur for four species of easement avoiders. These were small to medium-sized terrestrial birds associated with dense ground and/or understorey cover. The edge effect of fragmentation was an adverse impact on forest avifauna. At the margin (25?125 m from the easement) of the forest, bird abundance, mean species richness and total species richness were significantly less than the corresponding values for the interior (225?325 m) of the forest. The mean abundance at the sites varied from 13.0?17.7 birds/ha and the species richness varied significantly among sites. The adverse impacts of powerline easements on native avifauna could be minimized by site-specific management which includes strategies to minimize the loss of forest habitat and to ameliorate the effects of fragmentation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Haxton, Tim J., and C. Scott Findlay. "Meta-analysis of the impacts of water management on aquatic communities." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 3 (March 1, 2008): 437–47. http://dx.doi.org/10.1139/f07-175.

Texto completo

Resumen

Systematic meta-analyses were conducted on the ecological impacts of water management, including effects of (i) dewatering on macroinvertebrates, (ii) a hypolimnetic release on downstream aquatic fish and macro invertebrate communities, and (iii) flow modification on fluvial and habitat generalists. Our meta-analysis indicates, in general, that (i) macroinvertebrate abundance is lower in zones or areas that have been dewatered as a result of water fluctuations or low flows (overall effect size, –1.64; 95% confidence intervals (CIs), –2.51, –0.77), (ii) hypolimnetic draws are associated with reduced abundance of aquatic (fish and macroinvertebrates) communities (overall effect size, –0.84; 95% CIs, –1.38, –0.33) and macroinvertebrates (overall effect size, –0.73; 95% CIs, –1.24, –0.22) downstream of a dam, and (iii) altered flows are associated with reduced abundance of fluvial specialists (–0.42; 95% CIs, –0.81, –0.02) but not habitat generalists (overall effect size, –0.14; 95% CIs, –0.61, 0.32). Publication bias is evident in several of the meta-analyses; however, multiple experiments from a single study may be contributing to this bias. Fail-safe Ns suggest that many (>100) studies showing positive or no effects of water management on the selected endpoints would be required to qualitatively change the results of the meta-analysis, which in turn suggests that the conclusions are reasonably robust.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Geraldo de Carvalho, Fernando, Leandro Duarte, Gabriel Nakamura, Guilherme Dubal dos Santos Seger, and Leandro Juen. "Changes of Phylogenetic and Taxonomic Diversity of Odonata (Insecta) in Response to Land Use in Amazonia." Forests 12, no. 8 (August 9, 2021): 1061. http://dx.doi.org/10.3390/f12081061.

Texto completo

Resumen

Changes in natural habitats for human use can alter the distribution of biodiversity, favoring species that are more tolerant to environmental disturbance. Usually, these species comprise clades of habitat generalists, which have biological mechanisms to colonize environments with different environmental conditions. However, such effects are still poorly understood for most biological groups, such as the Amazon odonates. Therefore, this study aims to evaluate the effects of land use along an environmental gradient on the phylogenetic and taxonomic diversity of Odonata in the Amazon. We tested the following hypotheses: In deforested areas (e.g., pasture for cattle, palm plantation, and logging), the Odonata community will be more taxonomically and phylogenetically impoverished than in forested areas. We assume that the modification of the natural habitat causes loss of specialist forest species and favors specialist species of open areas and/or habitat generalists. Data sampling was performed in 195 streams under different land-use types: livestock areas, palm monoculture, timber exploitation, and forest areas taken as reference sites. Our results showed that anthropogenic impacts affected the phylogenetic diversity of odonates and the increase in shrub vegetation was related to the increase in the phylogenetic diversity of communities. On the other hand, shrub vegetation is indicative of disturbed areas, where secondary vegetation predominates, with less canopy cover due to the absence or discontinuity of the native tree cover in these habitats. Nonetheless, species richness and abundance were not related to the effects of anthropogenic land use. Finally, our results suggest that the phylogenetic diversity of Amazonian odonates is related to riparian vegetation structure.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Wrzesień, Małgorzata, and Bożena Denisow. "The effect of Agricultural Landscape Type on Field Margin Flora in South Eastern Poland." Acta Botanica Croatica 75, no. 2 (October 1, 2016): 217–25. http://dx.doi.org/10.1515/botcro-2016-0027.

Texto completo

Resumen

Abstract Plant species diversity is threatened in many agricultural landscapes due to the changes it has to undergo. Although the modification of the agricultural landscape pattern is observed across Europe, both extensive and intensive agricultural landscapes still co-exist in Poland. The objective of the study was to examine the flora in field margins in intensively and extensively managed agricultural landscapes, located across three regions in SE Poland. The flora was compared with respect to species richness, diversity, and evenness indices. Detrended correspondence analysis was employed to characterise variation in species composition. Agricultural landscape type made a higher contribution than the topography or geology to species richness and composition in field margins. Field margins function as important habitats for general vascular plant species diversity and are useful for the conservation of rare, threatened, endangered or bee plants. A significant decline in species diversity was observed over a distance of 1000 m from the habitat elements. Plants growing on field margins are mainly perennials; however participation of annuals clearly increases in intensive landscapes. The participation of wind-dispersed species decreased in an open-spaced intensive landscape. Animal-dispersed plants predominated in an extensive landscape with forest islands. Irrespective of landscape type, native species predominated. However, these habitats create the biota and corridors for alien-invasive species as well.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Dong, Yuan-Huo, Qing-Feng Wang, and Robert Wahiti Gituru. "Effect of Habitat Modification on the Distribution of the Endangered Aquatic Fern Ceratopteris pteridoides (Parkeriaceae) in China." American Fern Journal 102, no. 2 (April 2012): 136–46. http://dx.doi.org/10.1640/0002-8444-102.2.136.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Mokross, Karl, Thomas B. Ryder, Marina Corrêa Côrtes, Jared D. Wolfe, and Philip C. Stouffer. "Decay of interspecific avian flock networks along a disturbance gradient in Amazonia." Proceedings of the Royal Society B: Biological Sciences 281, no. 1776 (February 7, 2014): 20132599. http://dx.doi.org/10.1098/rspb.2013.2599.

Texto completo

Resumen

Our understanding of how anthropogenic habitat change shapes species interactions is in its infancy. This is in large part because analytical approaches such as network theory have only recently been applied to characterize complex community dynamics. Network models are a powerful tool for quantifying how ecological interactions are affected by habitat modification because they provide metrics that quantify community structure and function. Here, we examine how large-scale habitat alteration has affected ecological interactions among mixed-species flocking birds in Amazonian rainforest. These flocks provide a model system for investigating how habitat heterogeneity influences non-trophic interactions and the subsequent social structure of forest-dependent mixed-species bird flocks. We analyse 21 flock interaction networks throughout a mosaic of primary forest, fragments of varying sizes and secondary forest (SF) at the Biological Dynamics of Forest Fragments Project in central Amazonian Brazil. Habitat type had a strong effect on network structure at the levels of both species and flock. Frequency of associations among species, as summarized by weighted degree, declined with increasing levels of forest fragmentation and SF. At the flock level, clustering coefficients and overall attendance positively correlated with mean vegetation height, indicating a strong effect of habitat structure on flock cohesion and stability. Prior research has shown that trophic interactions are often resilient to large-scale changes in habitat structure because species are ecologically redundant. By contrast, our results suggest that behavioural interactions and the structure of non-trophic networks are highly sensitive to environmental change. Thus, a more nuanced, system-by-system approach may be needed when thinking about the resiliency of ecological networks.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Simeone, Alejandro, and Mariano Bernal. "Effects of Habitat Modification on Breeding Seabirds: A Case Study in Central Chile." Waterbirds: The International Journal of Waterbird Biology 23, no. 3 (2000): 449. http://dx.doi.org/10.2307/1522182.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Larsen, Angela L., Jessica A. Homyack, T. Bently Wigley, Darren A. Miller, and Matina C. Kalcounis-Rueppell. "Effects of habitat modification on cotton rat population dynamics and rodent community structure." Forest Ecology and Management 376 (September 2016): 238–46. http://dx.doi.org/10.1016/j.foreco.2016.06.018.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Blanco-Torres, Argelina, María Argenis Bonilla, and Luciano Cagnolo. "Habitat modification effects on anuran food webs in the Colombian tropical dry forest." Food Webs 22 (March 2020): e00133. http://dx.doi.org/10.1016/j.fooweb.2019.e00133.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Fritz, Ken M., Michael M. Gangloff, and Jack W. Feminella. "Habitat modification by the stream macrophyte Justicia americana and its effects on biota." Oecologia 140, no. 3 (June 17, 2004): 388–97. http://dx.doi.org/10.1007/s00442-004-1594-3.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Needham, Robert J., Martin Gaywood, Angus Tree, Nick Sotherton, Dylan Roberts, Colin W. Bean, and Paul S. Kemp. "The response of a brown trout (Salmo trutta) population to reintroduced Eurasian beaver (Castor fiber) habitat modification." Canadian Journal of Fisheries and Aquatic Sciences 78, no. 11 (November 2021): 1650–60. http://dx.doi.org/10.1139/cjfas-2021-0023.

Texto completo

Resumen

Globally, freshwaters are the most degraded and threatened of all ecosystems. In northern temperate regions, beaver (Castor spp.) reintroductions are increasingly used as a low-cost and self-sustaining means to restore river corridors. River modifications by beavers can increase availability of suitable habitat for fish, including salmonids. This study investigated the response of a population of brown trout (Salmo trutta) to reintroduced Eurasian beaver (Castor fiber) habitat modifications in northern Scotland. The field site comprised two streams entering a common loch; one modified by beavers, the other unaltered. Electrofishing and PIT telemetry surveys indicated abundance of post-young-of-the-year (post-YOY) trout was higher in the modified stream. Considering juvenile year groups (YOY and post-YOY) combined, abundance and density varied with year and season. In the modified stream, fork length and mass were greater, there was a greater variety of age classes, and mean growth was positive during all seasons. Beavers had profound effects on the local brown trout population that promoted higher abundances of larger size classes. This study provides important insight into the possible future effect of beavers on freshwater ecosystems.

Los estilos APA, Harvard, Vancouver, ISO, etc.

França, FGR, and AFB Araújo. "Are there co-occurrence patterns that structure snake communities in Central Brazil?" Brazilian Journal of Biology 67, no. 1 (February 2007): 33–40. http://dx.doi.org/10.1590/s1519-69842007000100005.

Texto completo

Resumen

The main factors that structure Neotropical animal communities have been the subject of discussion in ecology communities. We used a set of null models to investigate the existence of structure in snake communities from the Cerrado in Central Brazil in relation to the co-occurrence of species and guilds concerning specific resources. We used fragments (conservation units) inside the Distrito Federal and neighbor municipalities. In spite of recent human colonization in the region from the end of the 1950’s, intense habitat modification and fragmentation has taken place. Sixty three snake species are present in the Distrito Federal. Co-occurrence analysis of species and guilds associated to snake diets and habitats suggested a lack of organization. The homogeneity of habitats in Central Brazil and the minor importance of ecological effects can lead to random arrangement.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Mulieri, Pablo R., Luciano D. Patitucci, and Matías I. Dufek. "Occurrence of kleptoparasitic sarcophagid flies (Diptera: Sarcophagidae: Miltogramminae) in natural and human modified sites in Southern South American Andean landscapes." Revista de la Sociedad Entomológica Argentina 80, no. 3 (September 30, 2021): 1–12. http://dx.doi.org/10.25085/rsea.800301.

Texto completo

Resumen

Sarcophagid flies belonging to the subfamily Miltogramminae are mainly kleptoparasites of bees and solitary wasps. Twenty-six locations were surveyed to accomplish the first specific exploration on the diversity of Miltogramminae in southern Andean areas of South America. We evaluated changes in abundance, richness and composition among habitat types to establish the effect of anthropization on the Miltogramminae community. Habitat types were considered as human modified (trails and roads, parks and meadows) and natural sites (watercourses and lake beaches, sandy and shrubby areas), distributed in two ecoregions (Valdivian forest and Patagonian steppe). We found differences in the capture rate and composition of Miltogramminae among habitat types. The species Opsidia intonsa Aldrich was highly dominant in samples, with higher proportional abundance in human modified habitats. Richness of Miltogramminae was higher in natural sites. Comparisons between the ecoregions surveyed indicated the genus Opsidia Coquillett did not show differences in abundance between ecoregions, whereas Senotainia Macquart was more abundant in the Patagonian steppe. The results provide evidence on the significant effects of human influence on landscapes in kleptoparasitic fly diversity. Slight modifications of natural areas (as proliferation of trails or isolated houses) should be addressed to evaluate the conservation of kleptoparasitic Diptera.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Belton, Lydia E., Elissa Z. Cameron, and Fredrik Dalerum. "Spotted hyaena space use in relation to human infrastructure inside a protected area." PeerJ 4 (October 19, 2016): e2596. http://dx.doi.org/10.7717/peerj.2596.

Texto completo

Resumen

Increasing human population growth has led to elevated levels of human-carnivore conflict. However, some carnivore populations have adapted to urban environments and the resources they supply. Such associations may influence carnivore ecology, behaviour and life-history. Pockets of urbanisation sometimes occur within protected areas, so that anthropogenic influences on carnivore biology are not necessarily confined to unprotected areas. In this study we evaluated associations between human infrastructure and related activity and space use of spotted hyaenas within one of the largest protected areas in South Africa, the Kruger National Park. Home range size was smaller for the dominant female of a clan living in close proximity to humans than that of the dominant female of a clan without direct access to human infrastructure. The home range including human infrastructure was also used less evenly during the night, presumably when the animals were active. Within this home range, a village area was preferred during the night, when the least modified areas within the village were preferred and administration and highly modified areas were avoided. During the day, however, there were no preference or avoidance of the village area, but all habitats except unmodified habitats within the village area were avoided. We suggest that human infrastructure and associated activity influenced hyaena space use, primarily through alterations in the spatial distribution of food. However, these effects may have been indirectly caused by habitat modification that generated favourable hunting habitat rather than a direct effect caused by access to human food such as garbage. Because of the often pivotal effects of apex predators in terrestrial ecosystems, we encourage further work aimed to quantify how human presence influences large carnivores and associated ecosystem processes within protected areas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Połeć, Katarzyna, Antoni Grzywna, Monika Tarkowska-Kukuryk, and Urszula Bronowicka-Mielniczuk. "Changes in the Ecological Status of Rivers Caused by the Functioning of Natural Barriers." Water 14, no. 9 (May 9, 2022): 1522. http://dx.doi.org/10.3390/w14091522.

Texto completo

Resumen

Introducing the European beaver to the catchment area, which adjusts the habitat to its own needs (by building dams), may have a positive impact on the ecology, geology, and hydromorphology of rivers and intensify the water self-purification process. In this study, a comparative assessment of the ecological status was made between the areas where the species Castor fiber L. occurs (habitat type A) and the areas unaffected by the influence (habitat type B). For this purpose, the Macrophyte River Index (MIR) and the Hydromorphological River Index (HIR) were calculated, along with the floristic indicators of biodiversity: species richness and Margalef, Shannon–Wiener, and Simpson indices. Only 35% of the sites met the standard of good ecological status. The presence of hypertrophic species and anthropogenic modifications of the river bed had a negative impact. The spread of beavers has a significant positive effect on changes in hydromorphological conditions and water levels in the river. The water levels in habitat types A and B were 0.504 and 0.253 m, respectively. There were statistically significant differences in the HIR values between habitat types A and B, which were 0.585 and 0.535, respectively. In habitats of type A, the heterogeneity of the current and bed material as well as the diversity of elements accompanying the tree stands increased. Research has shown greater species richness and greater biodiversity of macrophytes in the habitats of beaver dams. The research confirmed the significant influence of the European beaver on changes in the environment. The activity of beavers intensifies the processes of introducing wetland and rush species to forest areas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Fonseka, Nalin, Jerome Goddard Ⅱ, Alketa Henderson, Dustin Nichols, and Ratnasingham Shivaji. "Modeling effects of matrix heterogeneity on population persistence at the patch-level." Mathematical Biosciences and Engineering 19, no. 12 (2022): 13675–709. http://dx.doi.org/10.3934/mbe.2022638.

Texto completo

Resumen

<abstract>Habitat loss and fragmentation is the largest contributing factor to species extinction and declining biodiversity. Landscapes are becoming highly spatially heterogeneous with varying degrees of human modification. Much theoretical study of habitat fragmentation has historically focused on a simple theoretical landscape with patches of habitat surrounded by a spatially homogeneous hostile matrix. However, terrestrial habitat patches are often surrounded by complex mosaics of many different land cover types, which are rarely ecologically neutral or completely inhospitable environments. We employ an extension of a reaction diffusion model to explore effects of heterogeneity in the matrix immediately surrounding a patch in a one-dimensional theoretical landscape. Exact dynamics of a population exhibiting logistic growth, an unbiased random walk in the patch and matrix, habitat preference at the patch/matrix interface, and two functionally different matrix types for the one-dimensional landscape is obtained. These results show existence of a minimum patch size (MPS), below which population persistence is not possible. This MPS can be estimated via empirically derived estimates of patch intrinsic growth rate and diffusion rate, habitat preference, and matrix death and diffusion rates. We conclude that local matrix heterogeneity can greatly change model predictions, and argue that conservation strategies should not only consider patch size, configuration, and quality, but also quality and spatial structure of the surrounding matrix.</abstract>

Los estilos APA, Harvard, Vancouver, ISO, etc.

R. Fulton, Graham. "The Negative Effects of Wildlife Tourism on Wildlife." Pacific Conservation Biology 8, no. 1 (2002): 67. http://dx.doi.org/10.1071/pc020067.

Texto completo

Resumen

THIS report is one of 23 in the Wildlife Tourism's Report Series, Edited by Dr Karen Higginbottom and targeted to industry, government users, and tourism researchers. Dr Green is both a research ecologist and an ecotour operator, with research interests in frugivorous seed dispersal and habitat modification. Dr Higginbottom is a lecturer at Griffith University where she teaches wildlife management, vertebrate biology, and nature based tourism.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Skilleter, G. A., and S. Warren. "Effects of habitat modification in mangroves on the structure of mollusc and crab assemblages." Journal of Experimental Marine Biology and Ecology 244, no. 1 (February 2000): 107–29. http://dx.doi.org/10.1016/s0022-0981(99)00133-1.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Larsen, Stefano, and S. J. Ormerod. "Combined effects of habitat modification on trait composition and species nestedness in river invertebrates." Biological Conservation 143, no. 11 (November 2010): 2638–46. http://dx.doi.org/10.1016/j.biocon.2010.07.006.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Jennings, Martin J., Michael A. Bozek, Gene R. Hatzenbeler, Edward E. Emmons, and Michael D. Staggs. "Cumulative Effects of Incremental Shoreline Habitat Modification on Fish Assemblages in North Temperate Lakes." North American Journal of Fisheries Management 19, no. 1 (February 1999): 18–27. http://dx.doi.org/10.1577/1548-8675(1999)019<0018:ceoish>2.0.co;2.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ludwiczak, Emilia, Mariusz Nietupski, and Agnieszka Kosewska. "Ground beetles (Coleoptera; Carabidae) as an indicator of ongoing changes in forest habitats due to increased water retention." PeerJ 8 (September 15, 2020): e9815. http://dx.doi.org/10.7717/peerj.9815.

Texto completo

Resumen

This study, concerning the epigeic fauna of carabid beetles (Coleoptera; Carabidae), was conducted in the north-east of Poland, in an area which is part of the Dąbrówka Forest Subdistrict and has been included in the “Small water retention program for the Province of Warmia and Mazury in 2006–2015”. The purpose of the study was to assess the impact of the water retention implemented within the framework of the above program on assemblages of ground beetles. These insects are highly sensitive to any anthropogenically induced transformations. This analysis was based on the interactions among the analyzed insects caused by changes occurring in their habitat. During the 3-year study, 5,807 specimens representing 84 species were captured. The water storage had a significant influence on the structure of the Carabidae assemblages. Before the earthworks were constructed for the project, the beetle assemblages had comprised a large group of xerophilous species, whereas after the small retention reservoirs had been created, an increase in the contribution of hygrophilous species was noticed. The results indicate that the retention works cause alterations in the water and environmental conditions of the habitats, and thereby effect changes in the composition of Carabidae assemblages. Moreover, modification in water relations within a habitat causes long-term changes in the structural and functional diversity of the beetles.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Janiak, DS, CJ Freeman, J. Seemann, JE Campbell, VJ Paul, and JE Duffy. "Spatial variation in the effects of predator exclusion on epifaunal community development in seagrass beds." Marine Ecology Progress Series 649 (September 10, 2020): 21–33. http://dx.doi.org/10.3354/meps13449.

Texto completo

Resumen

Biotic interactions have critical effects on the structure of ecological communities, and the variation in the strength of these interactions over space and time contributes to biogeographic variation in communities. Predation shapes community composition in a variety of habitats, although there have been comparatively few experimental studies of these effects across latitudinal scales. We tested the impact of predator exclusion on the development of epifaunal communities across 3 sites (Florida [USA], Belize, and Panama) in seagrass habitats dominated by Thalassia testudinum using caged and uncaged settlement panels. We found that predators altered composition and slowed development of epifaunal communities. The nature and magnitude of these effects, however, were complex, site-dependent, and tightly coupled to community development. Fast-growing, soft-bodied species dominated space when predators were excluded, while more resistant calcifying species were dominant in communities exposed to predators. In Panama, non-native ascidians dominated communities in cages, while ascidians were consumed when exposed to predators, indicating the importance of biotic resistance at that site. Predators also reduced the abundance of associated small mobile fauna, and the positive correlation between mobile faunal abundances and sessile biomass in our study suggests a potential indirect effect of predator-mediated habitat modification. Overall, prey characteristics were important in explaining the site-specific effects of predators on communities, indicating that taxonomic resolution can influence the results of multi-regional studies examining the mechanisms affecting community structure.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Bedla, Dawid, Wiktor Halecki, and Karol Król. "HYDROMORPHOLOGICAL METHOD AND GIS TOOLS WITH A WEB APPLICATION TO ASSESS A SEMI-NATURAL URBANISED RIVER." Journal of Environmental Engineering and Landscape Management 29, no. 1 (February 17, 2021): 21–32. http://dx.doi.org/10.3846/jeelm.2021.14187.

Texto completo

Resumen

River valleys are an essential element of urban space, and play an important role in the functioning of the natural environment and the recreation of city dwellers. Moreover, blue-green infrastructure facilitates healthy urban living. New technologies can contribute significantly to dissemination of messages of environmental protection. We discuss adaptation of the RHS method for presenting interactive data for river channels. Our assessment was focused on three parameters: habitat area, structure and conservation. The main parameters were described using selected indicators linked to natural and anthropogenic factors. The habitat modification score showed that the physical state of the Drwinka River was obviously modified, and the habitat quality assessment rated the stream as hydromorphological class III. The web application showed that the proposed method is suitable for creating realistic visual effects, and indicates greening areas against degraded areas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!