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731.
Rosaleen Duffy Freya A. V. St John Bram Büscher Dan Brockington 《Conservation biology》2016,30(1):14-22
Conservation organizations have increasingly raised concerns about escalating rates of illegal hunting and trade in wildlife. Previous studies have concluded that people hunt illegally because they are financially poor or lack alternative livelihood strategies. However, there has been little attempt to develop a richer understanding of the motivations behind contemporary illegal wildlife hunting. As a first step, we reviewed the academic and policy literatures on poaching and illegal wildlife use and considered the meanings of poverty and the relative importance of structure and individual agency. We placed motivations for illegal wildlife hunting within the context of the complex history of how wildlife laws were initially designed and enforced to indicate how hunting practices by specific communities were criminalized. We also considered the nature of poverty and the reasons for economic deprivation in particular communities to indicate how particular understandings of poverty as material deprivation ultimately shape approaches to illegal wildlife hunting. We found there is a need for a much better understanding of what poverty is and what motivates people to hunt illegally. 相似文献
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733.
734.
Timothée Schwartz Aurélien Besnard Christophe Pin Olivier Scher Thomas Blanchon Arnaud Béchet Nicolas Sadoul 《Conservation biology》2023,37(2):e14005
By rapidly modifying key habitat components, habitat restoration is at risk of producing attractive cues for animals without providing habitats of sufficient quality. As such, individual fitness components, such as reproduction, could be reduced and restored habitats could become ecological traps. This risk notably appears by using artificial constructions in restoration projects, yet few studies have evaluated their efficacy in a robust way. We investigated this by analyzing 154 islets that were created or restored to improve the conservation status of 7 colonial Laridae species in the South of France. From 2007 to 2016, we compared occupancy dynamics and breeding parameters of these species between the restored sites and 846 unmanaged nesting sites. We also explored species’ preference for different nesting site characteristics and their respective effect on breeding parameters. Restored nesting sites were 2–9 times as attractive as unmanaged sites for all species except the Black-headed Gull (Chroicocephalus ridibundus). Colonization probability was up to 100 times higher in sites already used by other species the previous year and increased with distance to the shore until >0.2 when distance was over 250 m. Abandonment probability was 29–70% lower when breeding was successful the previous year in all species except the Sandwich Tern (Thalasseus sandvicensis). Productivity and breeding success probability were 2 times higher on managed sites. Distance from the shore was an important attractive characteristic of artificial nesting sites in all species. Other nesting site characteristics had species-specific effects on colonization, abandonment, and breeding success. Our results indicate that managed nesting sites are successful conservation tools for colonial Laridae in the Mediterranean and do not act as ecological traps. Our study showed that testing the ecological trap hypothesis is a robust way to evaluate the success of restoration projects of breeding habitats. 相似文献
735.
Cicchella Domenico Hoogewerff Jurian Albanese Stefano Adamo Paola Lima Annamaria Taiani Manuela V. E. De Vivo Benedetto 《Environmental geochemistry and health》2016,38(2):619-637
Environmental Geochemistry and Health - The results of a large geochemical study on various environmental media (soil, stream sediment, groundwater, surface water, lettuce and human hair) of the... 相似文献
736.
737.
Nicole Shumway Megan I. Saunders Sam Nicol Richard A. Fuller Noam Ben-Moshe Takuya Iwamura Sun W. Kim Nicholas J. Murray James E. M. Watson Martine Maron 《Conservation biology》2023,37(2):e14031
Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian–Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement. 相似文献
738.
Chukwujindu M. A. Iwegbue Godwin E. Nwajei Jude E. Ogala Chukwudumebi L. Overah 《Environmental geochemistry and health》2010,32(5):415-430
The concentrations of trace metals (Cd, Pb, Cu, Cr, Fe, Ni, Zn and Co) were studied in soil profiles of eight municipal waste
dump sites in Warri metropolis. The results indicate that concentrations of trace metals varied widely among the different
dumpsites and decreased with depths in a studied soil profile. The accumulation pattern for the heavy metals in the soil profiles
follows the order: Fe > Pb > Mn > Co > Cr > Zn > Ni > Cu > Cd. The concentrations of metals found in these sites was below
the Canadian remediation criteria for land for agricultural, residential and commercial/industrial purposes except for the
cadmium levels in some sites that exceeded criterion values for agricultural and residential. In such sites, remedial actions
are required before any form of chosen development can take place. The levels of heavy metals found in these dump sites were
higher than that of the control site. The examined metals showed no significant correlation with soil physicochemical properties
at the surface horizon, which is suggestive evidence that these metals arise from anthropogenic input. 相似文献
739.
Augustine E. Ofomaja 《Journal of environmental management》2010,91(7):1491-1499
The equilibrium sorption of copper ions from aqueous solution using a new adsorbent, palm kernel fibre, has been studied. Palm kernel fibre is obtained in large amounts as a waste product of palm oil production. Batch equilibrium studies were carried out and system variables such as solution pH, sorbent dose, and sorption temperature were varied. The equilibrium sorption data was then analyzed using the Langmuir, Freundlich, Dubinin–Radushkevich (D–R) and Temkin isotherms. The fit of these isotherm models to the equilibrium sorption data was determined, using the linear coefficient of determination, r2, and the non-linear Chi-square, χ2 error analysis.The results revealed that sorption was pH dependent and increased with increasing solution pH above the pHPZC of the palm kernel fibre with an optimum dose of 10 g/dm3. The equilibrium data were found to fit the Langmuir isotherm model best, with a monolayer capacity of 3.17 × 10?4 mol/g at 339 K. The sorption equilibrium constant, Ka, increased with increasing temperature, indicating that bond strength between sorbate and sorbent increased with temperature and sorption was endothermic. This was confirmed by the increase in the values of the Temkin isotherm constant, B1, with increasing temperature. The Dubinin–Radushkevich (D–R) isotherm parameter, free energy, E, was in the range of 15.7–16.7 kJ/mol suggesting that the sorption mechanism was ion exchange. Desorption studies showed that a high percentage of the copper was desorbed from the adsorbent using acid solutions (HCl, HNO3 and CH3COOH) and the desorption percentage increased with acid concentration. The thermodynamics of the copper ions/palm kernel fibre system indicate that the process is spontaneous and endothermic. 相似文献
740.
Aarin Teague Philip B. Bedient Birnur Guven 《Journal of the American Water Resources Association》2011,47(3):620-634
Teague, Aarin, Philip B. Bedient, and Birnur Guven, 2011. Targeted Application of Seasonal Load Duration Curves Using Multivariate Analysis in Two Watersheds Flowing Into Lake Houston. Journal of the American Water Resources Association (JAWRA) 47(3):620‐634. DOI: 10.1111/j.1752‐1688.2011.00529.x Abstract: Water quality is a problem in Lake Houston, the primary source of drinking water for the City of Houston, Texas, due to pollutant loads coming from the influent watersheds, including Spring Creek and Cypress Creek. Statistical analysis of the historic water quality data was developed to understand the source characterization and seasonality of the watershed. Multivariate analysis including principal component, cluster, and discriminant analysis provided a custom seasonal assessment of the watersheds so that loading curves may be targeted for season specific pollutant source characterization. The load duration curves have been analyzed using data collected by the U.S. Geologic Survey with corresponding City of Houston water quality data at the sites to characterize the behavior of the pollutant sources and watersheds. Custom seasons were determined for Spring Creek and Cypress Creek watersheds and pollutant source characterization compared between the seasons and watersheds. 相似文献