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381.
A comparative approach to assess drivers of success in mammalian conservation recovery programs
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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
382.
Samuel G. Rees Anne E. GoodenoughAdam G. Hart Richard Stafford 《Ecological modelling》2011,222(17):3291-3294
Estimation of small mammal population sizes is important for monitoring ecosystem condition and for conservation. Here, we test the accuracy of standard methods of population size estimation using Capture-Mark-Recapture (CMR) on a simulated population of agents. The use of a computer simulation allows complete control of population sizes and behaviors, thereby avoiding assumptions that may be violated in real populations. We find that the recommended protocol for CMR sampling, using uniformly distributed traps, consistently overestimates population sizes by as much as 100% when studies are conducted over only two trapping periods. More than 20 trapping periods are required before this method, or that of placing traps randomly, gives an accurate estimation of population size (i.e., within a 95% confidence limit of the actual value). Non-random sampling, by placing traps on runways used by small mammals, produces the most accurate, and least variable, estimates of population. However, we show that around 10 trapping periods are still required to produce an accurate population estimate using this method. Given that most real populations do not comply with the ‘ideal’ assumptions made by CMR, we suggest that population estimates based on CMR may be fundamentally flawed, and recommend that protocols for CMR population estimation methods may need revising. 相似文献
383.
384.
Warsame Abdimalik Ali Sheik-Ali Ibrahim Abdukadir Ali Abdullahi Osman Sarkodie Samuel Asumadu 《Environmental science and pollution research international》2021,28(16):19838-19850
Environmental Science and Pollution Research - The purpose of this research examination is to ascertain the effect of climate change, measured rainfall, temperature, and CO2, on crop production by... 相似文献
385.
Pathways from chlorinated phenols as precursors to PCDD/Fs are discussed with focus on the effect of (poly)chlorination on thermochemistry and rate in the displacement of chlorine from a chlorophenol molecule by a (chloro)phenoxy radical (reaction (A) as a key example). Through measurements on the respective methylethers (anisoles) the O-H bond of 2,4,6-TCP turns out to be 5 kcal/ mol, and that in PCP 4 kcal/mol, less strong than O-H in phenol itself. On this basis it is concluded that-in contrast with earlier proposals--displacements such as in reaction (A) are at least as slow as reaction (B) of phenoxy radical with chlorobenzene. PhO. + PhCl -->PhOPh + Cl. reaction B Compared with condensation of two (chloro)phenoxy radicals, such radical/molecule reactions are therefore an insignificant pathway to dioxins in incinerators. 相似文献
386.
Nicolas P. Zegre Andrew J. Miller Aaron Maxwell Samuel J. Lamont 《Journal of the American Water Resources Association》2014,50(5):1257-1272
In the Appalachian region of the eastern United States, mountaintop removal mining (MTM) is a dominant driver of land‐cover change, impacting 6.8% of the largely forested 4.86 million ha coal fields region. Recent catastrophic flooding and documented biological impairment downstream of MTM has drawn sharp criticism to this practice. Despite its extent, scale, and use since the 1970s, the impact of MTM on hydrology is poorly understood. Therefore, the goal of this study was a multiscale evaluation to establish the nature of hydrologic impacts associated with MTM. To quantify the extent of MTM, land‐cover change over the lifetime of this practice is estimated for a mesoscale watershed in southern West Virginia. To assess hydrologic impacts, we conducted long‐term trend analyses to evaluate for systematic changes in hydrology at the mesoscale, and conducted hydrometric and response time modeling to characterize storm‐scale responses of a MTM‐impacted headwater catchment. Results show a general trend in the conversion of forests to mines, and significant decreases in maximum streamflow and variability, and increases in base‐flow ratio attributed to valley fills and deep mine drainage. Decreases in variability are shown across spatial and temporal scales having important implications for water quantity and quality. However, considerable research is necessary to understand how MTM impacts hydrology. In an effort to inform future research, we identify existing knowledge gaps and limitations of our study. 相似文献
387.
Samuel Benin Simeon Ehui John Pender 《Environment, Development and Sustainability》2003,5(3-4):491-510
Since 1991, there have been significant changes in utilization of feed resources in the Ethiopian highlands: while use of communal grazing lands and private pastures has declined, use of crop residues and purchased feed has increased. In addition, although use of animal health services and adoption of improved livestock breeds and modern management practices have increased, ownership of various types of livestock has declined. Rapid population growth has contributed most to the declining trends in grazing resources and ownership of livestock, showing the negative effects of increasing pressure on already degraded resources in the Ethiopian highlands. Land redistribution, increased participation in credit and extension programs targeting livestock, and improvement in access to markets, on the other hand, have had significant positive impacts on adoption of improved livestock technologies and ownership of livestock. Thus, reducing population growth and improving access to markets and credit and extension programs targeting livestock can enhance the role of livestock in improving food security and reducing poverty, especially in the mixed crop-livestock farming systems as exist in the East African highlands. 相似文献
388.
Takam Brice Acayanka Elie Kamgang Georges Y. Pedekwang Merlin T. Laminsi Samuel 《Environmental science and pollution research international》2017,24(20):16958-16970
Environmental Science and Pollution Research - Removal of cationic dye, Azur II, and anionic dye, Reactive Red 2 (RR-2) from aqueous solutions, has been successfully achieved by using a modified... 相似文献
389.
Juan Peris-Vicente Ana Marzo-Mas Pasqual Roca-Genovés Samuel Carda-Broch Josep Esteve-Romero 《环境科学学报(英文版)》2016,28(4):284-292
A method based on micellar liquid chromatography has been developed to simultaneously monitor four pesticides largely post-harvest applied to citrus:thiabendazole,pyrimethanil,o-phenylphenol and imazalil.Water samples were filtered and directly injected without other treatment,thus avoiding extraction steps.The composition of the mobile phase was optimized using a chemometrical approach to achieve and excellent resolution to 0.07 mol/L SDS/5%,V/V 1-pentanol buffered at p H 3.Mobile phase run through a C18 column at 1 m L/min at room temperature.The detection was performing by UV–Visible absorbance using a wavelength program:0–10 min,305 nm(for thiabendazole);10–12;265 nm(for pyrimethanil)and 12–18,220 nm(o-phenylphenol and imazalil).The developed method was validated following the guidelines of the US Environmental Protection Agency in terms of:quantitation range,(0.5–4 to 15μg/m L),linearity(r20.9995),sensitivity(LOD,0.18–1.4μg/m L),precision(9.2%),trueness(93.9%–103.7%),and ruggedness(9.9%).It was found that the fungicides remain up to eight days in surface water at outdoor conditions.The method was used to screen the presence of the analytes in several waste water samples,and was proved to be useful in routine analysis. 相似文献
390.
Owoyemi Jacob Mayowa Opara Emmanuel Uchechukwu Akande Samuel Olumide Olarenwaju Joshua Tosin Fuwape Joseph Adeola 《Environment, Development and Sustainability》2022,24(8):10309-10336
Environment, Development and Sustainability - Siting of buildings in rural urban development requires that the prevalence of termite activities is considered. The severity of termite activities... 相似文献