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181.
A comparative approach to assess drivers of success in mammalian conservation recovery programs 下载免费PDF全文
Jennifer J. Crees Amy C. Collins P. J. Stephenson Helen M. R. Meredith Richard P. Young Caroline Howe Mark R. Stanley Price Samuel T. Turvey 《Conservation biology》2016,30(4):694-705
The outcomes of species recovery programs have been mixed; high‐profile population recoveries contrast with species‐level extinctions. Each conservation intervention has its own challenges, but to inform more effective management it is imperative to assess whether correlates of wider recovery program success or failure can be identified. To contribute to evidence‐based improvement of future conservation strategies, we conducted a global quantitative analysis of 48 mammalian recovery programs. We reviewed available scientific literature and conducted semistructured interviews with conservation professionals involved in different recovery programs to investigate ecological, management, and political factors associated with population recoveries or declines. Identifying and removing threats was significantly associated with increasing population trend and decreasing conservation dependence, emphasizing that populations are likely to continue to be compromised in the absence of effective threat mitigation and supporting the need for threat monitoring and adaptive management in response to new and potential threats. Lack of habitat and small population size were cited as limiting factors in 56% and 42% of recovery programs, respectively, and both were statistically associated with increased longer term dependence on conservation intervention, demonstrating the importance of increasing population numbers quickly and restoring and protecting habitat. Poor stakeholder coordination and management were also regularly cited by respondents as key weaknesses in recovery programs, indicating the importance of effective leadership and shared goals and management plans. Project outcomes were not influenced by biological or ecological variables such as body mass or habitat, which suggests that these insights into correlates of conservation success and failure are likely to be generalizable across mammals. 相似文献
182.
Mandour Ahmed S. Elsayed Roushdy F. Ali Asmaa O. Mahmoud Ahmed E. Samir Haney Dessouki Amina A. Matsuura Katsuhiro Watanabe Izumi Sasaki Kazuaki Al-Rejaie Salim Yoshida Tomohiko Shimada Kazumi Tanaka Ryou Watanabe Gen 《Environmental science and pollution research international》2021,28(7):7815-7827
Environmental Science and Pollution Research - Copper deficiency (CuD) is a common mineral disorder in ruminants, which causes histomorphological changes in the heart due to disturbances in... 相似文献
183.
Nitrogen management in bioreactor landfills 总被引:17,自引:0,他引:17
One scenario for long-term nitrogen management in landfills is ex situ nitrification followed by denitrification in the landfill. The objective of this research was to measure the denitrification potential of actively decomposing and well decomposed refuse. A series of 10-l reactors that were actively producing methane were fed 400 mg NO3-N /l every 48 h for periods of 19-59 days. Up to 29 nitrate additions were either completely or largely depleted within 48 h of addition and the denitrification reactions did not adversely affect the leachate pH. Nitrate did inhibit methane production, but the reactors recovered their methane-producing activity with the termination of nitrate addition. In well decomposed refuse, the nitrate consumption rate was reduced but was easily stimulated by the addition of either acetate or an overlayer of fresh refuse. Addition of acetate at five times the amount required to reduce nitrate did not lead to the production of NH4+ by dissimilatory nitrate reduction. The most probable number of denitrifying bacteria decreased by about five orders of magnitude during refuse decomposition in a reactor that did not receive nitrate. However, rapid denitrification commenced immediately with nitrate addition. This study shows that the use of a landfill as a bioreactor for the conversion of nitrate to a harmless byproduct, nitrogen gas, is technically viable. 相似文献
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Kate A. Schofield Laurie C. Alexander Caroline E. Ridley Melanie K. Vanderhoof Ken M. Fritz Bradley C. Autrey Julie E. DeMeester William G. Kepner Charles R. Lane Scott G. Leibowitz Amina I. Pollard 《Journal of the American Water Resources Association》2018,54(2):372-399
Freshwater ecosystems are linked at various spatial and temporal scales by movements of biota adapted to life in water. We review the literature on movements of aquatic organisms that connect different types of freshwater habitats, focusing on linkages from streams and wetlands to downstream waters. Here, streams, wetlands, rivers, lakes, ponds, and other freshwater habitats are viewed as dynamic freshwater ecosystem mosaics (FEMs) that collectively provide the resources needed to sustain aquatic life. Based on existing evidence, it is clear that biotic linkages throughout FEMs have important consequences for biological integrity and biodiversity. All aquatic organisms move within and among FEM components, but differ in the mode, frequency, distance, and timing of their movements. These movements allow biota to recolonize habitats, avoid inbreeding, escape stressors, locate mates, and acquire resources. Cumulatively, these individual movements connect populations within and among FEMs and contribute to local and regional diversity, resilience to disturbance, and persistence of aquatic species in the face of environmental change. Thus, the biological connections established by movement of biota among streams, wetlands, and downstream waters are critical to the ecological integrity of these systems. Future research will help advance our understanding of the movements that link FEMs and their cumulative effects on downstream waters. 相似文献
186.
R.B. Neveril J.U. Price K.L. Engdahl 《Journal of the Air & Waste Management Association (1995)》2013,63(8):829-836
This is the first installment of a 4-part series which will present capital and operating costs of selected air pollution control systems. The objective of the Series is to identify the individual component costs so that realistic system cost estimates can be determined for any specific application. In Part I, cost estimating procedures and curves are provided to develop the equipment costs for electrostatic pre-cipitators, venturi scrubbers, fabric filters, incinerators, and adsorbers. 相似文献
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Oliver R. Price Dawn K. Munday Martin S. Holt Gerard Morris 《Environmental pollution (Barking, Essex : 1987)》2009,157(10):2610-2616
Higher-tier environmental risk assessments on “down-the-drain” chemicals in river networks can be conducted using models such as GREAT-ER (Geography-referenced Regional Exposure Assessment Tool for European Rivers). It is important these models are evaluated and their sensitivities to input variables understood. This study had two primary objectives: evaluate GREAT-ER model performance, comparing simulated modelled predictions for LAS (linear alkylbenzene sulphonate) with measured concentrations, for four rivers in the UK, and investigate model sensitivity to input variables. We demonstrate that the GREAT-ER model is very sensitive to variability in river discharges. However it is insensitive to the form of distributions used to describe chemical usage and removal rate in sewage treatment plants (STPs). It is concluded that more effort should be directed towards improving empirical estimates of effluent load and reducing uncertainty associated with usage and removal rates in STPs. Simulations could be improved by incorporating the effect of river depth on dissipation rates. 相似文献
189.
We examined regional conditions and trends related to quality of life and potential vulnerabilities of these factors to changes in the condition of natural resources in the Mid-Atlantic Region, USA. We selected a variety of variables on economic and socio-demographic conditions that demonstrate links between the condition of natural areas and human concerns and that quantify dependencies on resources. We extracted data from economic and population census databases for counties within the study area and present a subset of results of the cluster analyses used to describe condition and potential risks due to distinct combinations of variables. We found that the same variables used to judge quality of life were often correlated with increasing population and thus were likely to be related to land pressures and risks to natural resources. Within the region, economic dependence on resource-harvesting industries such as forestry and fisheries was low (less than 4% of total earnings at most), however, the potential for natural amenities to attract residents appeared to be growing as the self-employed and otherwise mobile people settled in areas with affordable housing and natural amenities. Suburban residential spread had been occurring in both the close-in and distant suburbs of the region's urban areas and some rural, growth appeared to be driven, in part, by businesses migrating to suburbs. Further work is needed to tease apart causal factors for the trends we observed, but correlations clearly existed in some areas between increasing populations and quality of natural surroundings. 相似文献
190.
Iodine-129 in controlled amounts has been released into the air from the operating chemical separations facilities on the Hanford Site. Small amounts of 129I have accumulated in surface soils especially at locations near the chemical separations facilities. Enriched levels of 129I also occur in the thyroid glands of mule deer (Odocoileus hemionus) residing on the Hanford Site.Stable iodine is present in low concentrations in Hanford Site soils and it is not avidly accumulated by wild plants. Soils at high elevations have greater concentrations of 127I than low elevations soils. Mule deer thyroids had higher concentrations of stable iodine than the thyroids of black-tailed jackrabbits. Stable iodine in black-tailed jackrabbit thyroids varied with the season with maximal concentrations in summer.Iodine-131 has not been released into the air from operating chemical separations facilities for more than 10 yr. Because of its short half-life 131I of Hanford Site origin has disappeared from the Hanford Site. In the event of a future restart of the chemical separations facilities black-tailed jackrabbits can be used as biological indicators of 131I in the terrestrial environment of the Hanford Site. 相似文献