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81.
James D. Salierno Melissa Lopes Michelle Rivera 《Journal of environmental science and health. Part. B》2016,51(10):695-702
The objective of this study was to evaluate the effects of early life stage triclosan (5-chloro-2-(2,4, dichlorophenoxy)phenol, TCS) exposure on hatching, development, and survival in the fathead minnow, Pimephales promelas. Embryonic minnows were exposed to TCS (50 and 100 µg L?1) for 10 days followed by 6 weeks depuration. Mortality and morphological deformities were recorded and quantified during exposure and at the end of depuration. No significant effects on embryonic survival, time to reach the eyed stage, or hatching were found. However, at the conclusion of the depuration period, survival was significantly reduced in TCS exposed fish depending on the concentration. Visual inspection of the exposed fish suggests that mortality is related to spinal deformities, emaciation, and reduced foraging ability. Triclosan exhibits deleterious effects in fish at lower concentrations over longer durations than previously reported. Further, mortality in exposed fish 6 weeks after exposure demonstrates the need for various exposure assays to evaluate effects of TCS. 相似文献
82.
Conservation implications of physiological carry‐over effects in bats recovering from white‐nose syndrome 下载免费PDF全文
Christina M. Davy Gabriela F. Mastromonaco Julia L. Riley James H. Baxter‐Gilbert Heather Mayberry Craig K.R. Willis 《Conservation biology》2017,31(3):615-624
Although it is well documented that infectious diseases can pose threats to biodiversity, the potential long‐term consequences of pathogen exposure on individual fitness and its effects on population viability have rarely been studied. We tested the hypothesis that pathogen exposure causes physiological carry‐over effects with a pathogen that is uniquely suited to this question because the infection period is specific and time limited. The fungus Pseudogymnoascus destructans causes white‐nose syndrome (WNS) in hibernating bats, which either die due to the infection while hibernating or recover following emergence from hibernation. The fungus infects all exposed individuals in an overwintering site simultaneously, and bats that survive infection during hibernation clear the pathogen within a few weeks following emergence. We quantified chronic stress during the active season, when bats are not infected, by measuring cortisol in bat claws. Free‐ranging Myotis lucifugus who survived previous exposure to P. destructans had significantly higher levels of claw cortisol than naïve individuals. Thus, cryptic physiological carry‐over effects of pathogen exposure may persist in asymptomatic, recovered individuals. If these effects result in reduced survival or reproductive success, they could also affect population viability and even act as a third stream in the extinction vortex. For example, significant increases in chronic stress, such as those indicated here, are correlated with reduced reproductive success in a number of species. Future research should directly explore the link between pathogen exposure and the viability of apparently recovered populations to improve understanding of the true impacts of infectious diseases on threatened populations. 相似文献
83.
Riggs Rebecca Anne Langston James Douglas Beauchamp Emilie Travers Henry Ken Sereyrotha Margules Chris 《Environmental management》2020,66(1):72-90
Environmental Management - Tropical forest landscapes are undergoing rapid transition. Rural development aspirations are rising, and land use change is contributing to deforestation, degradation,... 相似文献
84.
Cara E. Brook James P. Herrera Cortni Borgerson Emma C. Fuller Pascal Andriamahazoarivosoa B. J. Rodolph Rasolofoniaina J. L. Rado Ravoavy Randrianasolo Z. R. Eli Rakotondrafarasata Hervet J. Randriamady Andrew P. Dobson Christopher D. Golden 《Conservation biology》2019,33(1):99-111
Subsistence hunting presents a conservation challenge by which biodiversity preservation must be balanced with safeguarding of human livelihoods. Globally, subsistence hunting threatens primate populations, including Madagascar's endemic lemurs. We used population viability analysis to assess the sustainability of lemur hunting in Makira Natural Park, Madagascar. We identified trends in seasonal hunting of 11 Makira lemur species from household interview data, estimated local lemur densities in populations adjacent to focal villages via transect surveys, and quantified extinction vulnerability for these populations based on species-specific demographic parameters and empirically derived hunting rates. We compared stage-based Lefkovitch with periodic Leslie matrices to evaluate the impact of regional dispersal on persistence trajectories and explored the consequences of perturbations to the timing of peak hunting relative to the lemur birth pulse, under assumptions of density-dependent reproductive compensation. Lemur hunting peaked during the fruit-abundant wet season (March–June). Estimated local lemur densities were roughly inverse to body size across our study area. Life-history modeling indicated that hunting most severely threatened the species with the largest bodies (i.e., Hapalemur occidentalis, Avahi laniger, Daubentonia madagascariensis, and Indri indi), characterized by late-age reproductive onsets and long interbirth intervals. In model simulations, lemur dispersal within a regional metapopulation buffered extinction threats when a majority of local sites supported growth rates above the replacement level but drove regional extirpations when most local sites were overharvested. Hunt simulations were most detrimental when timed to overlap lemur births (a reality for D. madagascariensis and I. indri). In sum, Makira lemurs were overharvested. Regional extirpations, which may contribute to broad-scale extinctions, will be likely if current hunting rates persist. Cessation of anthropogenic lemur harvest is a conservation priority, and development programs are needed to help communities switch from wildlife consumption to domestic protein alternatives. 相似文献
85.
Joshua Eli Cinner Morgan Stuart Pratchett Nicholas Anthony James Graham Vanessa Messmer Mariana Menezes Prata Bezerra Fuentes Tracy Ainsworth Natalie Ban Line Kolind Bay Jessica Blythe Delphine Dissard Simon Dunn Louisa Evans Michael Fabinyi Pedro Fidelman Joana Figueiredo Ashley John Frisch Christopher John Fulton Christina Chemtai Hicks Vimoksalehi Lukoschek Jennie Mallela Aurelie Moya Lucie Penin Jodie Lynn Rummer Stefan Walker David Hall Williamson 《Regional Environmental Change》2016,16(4):1133-1146
Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people. 相似文献
86.
Jennifer H. Westerman James W. Westerman Brian G. Whitaker 《Environment, Development and Sustainability》2016,18(2):561-576
Recent conjecture on the potential primacy of physical environmental components in education for sustainable development (ESD) efforts serves to question the centrality of social justice education as a component of ESD. This research explores a sustainable development student’s basic knowledge of social justice conditions in their country of residence and its relationships to policy attitudes that should be of importance to ESD, including beliefs about the importance of corporate social responsibility, their endorsement of gross national product as an effective measure of progress, their overall assessment of the social fairness of current national social justice policy, and their endorsement of the goals of Occupy Wall Street. Results obtained using path-model hypothesis testing indicate that accuracy of knowledge of US standing on social justice issues is significantly related to these policy attitudes, providing support for social justice content in ESD endeavors to create students empowered for engagement in broader policy goals. 相似文献
87.
Augmenting Watershed Model Calibration with Incorporation of Ancillary Data Sources and Qualitative Soft Data Sources 下载免费PDF全文
Haw Yen Michael J. White James C. Ascough II Douglas R. Smith Jeffrey G. Arnold 《Journal of the American Water Resources Association》2016,52(3):788-798
Watershed simulation models such as the Soil & Water Assessment Tool (SWAT) can be calibrated using “hard data” such as temporal streamflow observations; however, users may find upon examination of model outputs, that the calibrated models may not reflect actual watershed behavior. Thus, it is often advantageous to use “soft data” (i.e., qualitative knowledge such as expected denitrification rates that observed time series do not typically exist) to ensure that the calibrated model is representative of the real world. The primary objective of this study is to evaluate the efficacy of coupling SWAT‐Check (a post‐evaluation framework for SWAT outputs) and IPEAT‐SD (Integrated Parameter Estimation and Uncertainty Analysis Tool‐Soft & hard Data evaluation) to constrain the bounds of soft data during SWAT auto‐calibration. IPEAT‐SD integrates 59 soft data variables to ensure SWAT does not violate physical processes known to occur in watersheds. IPEAT‐SD was evaluated for two case studies where soft data such as denitrification rate, nitrate attributed from subsurface flow to total discharge ratio, and total sediment loading were used to conduct model calibration. Results indicated that SWAT model outputs may not satisfy reasonable soft data responses without providing pre‐defined bounds. IPEAT‐SD provides an efficient and rigorous framework for users to conduct future studies while considering both soft data and traditional hard information measures in watershed modeling. 相似文献
88.
Lauren Withycombe Keeler Arnim Wiek Daniel J. Lang Makoto Yokohari John van Breda Lennart Olsson Barry Ness Jordi Morato Jordi Segalàs Pim Martens Luis A. Bojórquez-Tapia James Evans 《Sustainability Science》2016,11(5):749-762
A promising approach for addressing sustainability problems is to recognize the unique conditions of a particular place, such as problem features and solution capabilities, and adopt and adapt solutions developed at other places around the world. Therefore, research and teaching in international networks becomes critical, as it allows for accelerating learning by sharing problem understandings, successful solutions, and important contextual considerations. This article identifies eight distinct types of research and teaching collaborations in international networks that can support such accelerated learning. The four research types are, with increasing intensity of collaboration: (1) solution adoption; (2) solution consultation; (3) joint research on different problems; and (4) joint research on similar problems. The four teaching types are, with increasing intensity of collaboration: (1) adopted course; (2) course with visiting faculty; (3) joint course with traveling faculty; and (4) joint course with traveling students. The typology is illustrated by extending existing research and teaching projects on urban sustainability in the International Network of Programs in Sustainability, with partner universities from Europe, North America, Asia, and Africa. The article concludes with challenges and strategies for extending individual projects into collaborations in international networks. 相似文献
89.
Detention Outlet Retrofit Improves the Functionality of Existing Detention Basins by Reducing Erosive Flows in Receiving Channels 下载免费PDF全文
Robert J. Hawley James A. Goodrich Nora L. Korth Christopher J. Rust Elizabeth V. Fet Craig Frye Katherine R. MacMannis Matthew S. Wooten Mark Jacobs Rajib Sinha 《Journal of the American Water Resources Association》2017,53(5):1032-1047
By discharging excess stormwater at rates that more frequently exceed the critical flow for stream erosion, conventional detention basins often contribute to increased channel instability in urban and suburban systems that can be detrimental to aquatic habitat and water quality, as well as adjacent property and infrastructure. However, these ubiquitous assets, valued at approximately $600,000 per km2 in a representative suburban watershed, are ideal candidates to aid in reversing such cycles of channel degradation because improving their functionality would not necessarily require property acquisition or heavy construction. The objective of this research was to develop a simple, cost‐effective device that could be installed in detention basin outlets to reduce the erosive power of the relatively frequent storm events (~ < two‐year recurrence) and provide a passive bypass to maintain flood control performance during infrequent storms (such as the 100‐year recurrence). Results from a pilot installation show that the Detain H2O device reduced the cumulative sediment transport capacity of the preretrofit condition by greater than 40%, and contributed to reduced flashiness and prolonged baseflows in receiving streams. When scaling the strategy across a watershed, these results suggest that potential gains in water quality and stream channel stability could be achieved at costs that are orders of magnitude less than comparable benefits from newly constructed stormwater control measures. 相似文献
90.
Sivanandham Vignesh Hans-Uwe Dahms Kunnampuram Varghese Emmanuel Murugaiah Santhosh Gokul Krishnan Muthukumar Bong-Rae Kim Rathinam Arthur James 《Environmental monitoring and assessment》2014,186(3):1875-1887
A total of 176 (water and sediment) samples from 22 stations belonging to four different (urban, semi-urban, rural, and holy places) human habitations of Tamil Nadu beaches were collected and analyzed for physiochemical and microbial parameters during 2008–2009. Bacterial counts were two- to tenfold higher in sediments than in water due to strong bacterial aggregations by dynamic flocculation and rich organic content. The elevated bacterial communities during the monsoon explain rainfalls and several other wastes from inlands. Coliform counts drastically increased at holy and urban places due to pilgrimage and other ritual activities. Higher values of the pollution index (PI) ratio (>1) reveals, human fecal pollutions affect the water quality. The averaged PI ratio shows a substantial higher microbial contamination in holy places than in urban areas and the order of decreasing PI ratios observed were: holy places?>?urban areas?>?semi-urban areas?>?rural areas. Correlation and factor analysis proves microbial communities were not related to physicochemical parameters. Principal component analysis indicates 55.32 % of the total variance resulted from human/animal fecal matters and sewage contaminants whereas 19.95 % were related to organic contents and waste materials from the rivers. More than 80 % of the samples showed a higher fecal coliform and Streptococci by crossing the World Health Organization's permissible limits. 相似文献