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Harnessing the economic potential of the oceans is key to combating poverty, enhancing food security, and strengthening economies. But the concomitant risk of intensified resource extraction to migratory species is worrying given these species contribute to important ecological processes, often underpin alternative livelihoods, and are mostly already threatened. We thus sought to quantify the potential conflict between key economic activities (5 fisheries and hydrocarbon exploitation) and sea turtle migration corridors in a region with rapid economic development: southern and eastern Africa. We satellite tracked the movement of 20 loggerhead (Caretta caretta) and 14 leatherback (Dermochelys coriacea) turtles during their postnesting migrations. We used movement‐based kernel density estimation to identify migration corridors for each species. We overlaid these corridors on maps of the distribution and intensity of economic activities, quantified the extent of overlap and threat posed by each activity on each species, and compared the effects of activities. These results were compared with annual bycatch rates in the respective fisheries. Both species’ 3 corridors overlapped most with longline fishing, but the effect was worse for leatherbacks: their bycatch rates of approximately 1500/year were substantial relative to the regional population size of <100 nesting females/annum. This bycatch rate is likely slowing population growth. Artisanal fisheries may be of greater concern for loggerheads than for leatherbacks, but the population appears to be withstanding the high bycatch rates because it is increasing exponentially. The hydrocarbon industry currently has a moderately low impact on both species, but mining in key areas (e.g., Southern Mozambique) may undermine >50 years of conservation, potentially affecting >80% of loggerheads, 33% of the (critically endangered) leatherbacks, and their nesting beaches. We support establishing blue economies (i.e., generating wealth from the ocean), but oceans need to be carefully zoned and responsibly managed in both space and time to achieve economic (resource extraction), ecological (conservation, maintenance of processes), and social (maintenance of alternative livelihood opportunities, alleviate poverty) objectives.  相似文献   
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Rewilding is increasingly recognized as a conservation tool but is often context specific, which inhibits broad application. Rewilding in Australia seeks to enhance ecosystem function and promote self-sustaining ecosystems. An absence of large-bodied native herbivores means trophic rewilding in mainland Australia has focused on the restoration of functions provided by apex predators and small mammals. Because of the pervasive influence of introduced mesopredators, predator-proof fences, and establishment of populations on predator-free islands are common rewilding approaches. This sets Australian rewilding apart from most jurisdictions and provides globally relevant insights but presents challenges to restoring function to broader landscapes. Passive rewilding is of limited utility in arid zones. Although increasing habitat extent and quality in mesic coastal areas may work, it will likely be necessary to undertake active management. Because much of Australia's population is in urban areas, rewilding efforts must include urban areas to maximize effectiveness. Thus rewilding is not synonymous with wilderness and can occur over multiple scales. Rewilding efforts must recognize human effects on other species and benefit both nature and humans. Rewilding in Australia requires development of a shared vision and strategy and proof-of-concept projects to demonstrate the benefits. The repackaging of existing conservation activities as rewilding may confuse and undermine the success of rewilding programs and should be avoided. As elsewhere, rewilding in Australia should be viewed as an important conservation tool.  相似文献   
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主流消费者期望具有更持久的购买力,但前提是(至少今天是)这种要求不会造成费用、质量、时尚或功能方面的牺牲.零售部门面临的挑战就是如何鼓励消费者、供应商、雇员和利益相关者向夺取更可持续生产方式和可持续消费努力.Marks和Spencer已经得到的改进不仅仅在财务方面,而且还在于找到履行法人社会职责(CSR)的通道."法人社会职责"和"可持续性"这两个词汇经常被交替使用;Marks和Spencer把"法人社会职责"看做是管理程序,通过它就有可能朝着一个更可持续性的商业模式前进.  相似文献   
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Two water treatment sludges (WTS-A, WTS-B), two red muds (RM), and red gypsum (RG), all rich in iron oxy-hydroxides, were added to a soil highly polluted with As and Cu at 2% (w/w) to reduce metal bioavailability. Because the amendments increased soil pH to approximately 6, a lime treatment to the same pH and an unamended treatment were included for comparison. All the amendments had significant positive effects on the soil microbial biomass and growth of ryegrass (Lolium multiflorum Lam. cv. Avance), but only WTS-A improved lettuce (Lactuca sativa L. cv. Tom Thumb) growth. The mineralization of added ammonium nitrogen was not significantly affected by the treatments, while a physiologically based extraction test (PBET) showed that bioaccessibility of As was low (< 5%) and decreased only in the WTS-A treatment. Concentrations of As in soil pore water and extractable As only decreased in the WTS and RG treatments. In contrast, Cu concentrations in soil pore water and extractable Cu decreased in all treatments, by more than 84% in the WTS, RM, and RG treatments. Non-isotopically exchangeable As and Cu were present in colloids in the soil pore water. Untreated soil had < 4% isotopically exchangeable As and this decreased by approximately 50%, with WTS, RM, and RG. The labile Cu pool represented a large proportion (34%) of the total Cu pool, and the isotopically exchangeable and soluble Cu were strongly correlated with soil pH. Acidification of the treated soils showed that the labile As and Cu both increased in the treated soils compared with untreated soils. The significance of the treatment effects on soil fertility and potential off-site transport of As and Cu to ground water are discussed.  相似文献   
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This work describes TCE biotic removal in a single-pulse bioreactor under aerobic conditions. Activated sludge from a wastewater-treatment plant was used for inoculation of the cultivator. The experiment focused on a more detailed verification of microbial composition of mixed heterotrophic culture during pulsed phenol dosage. Attention was given to suppressing eucaryotic organisms, particularly yeasts and fungi, by the addition of cycloheximide. The TCE-removal capacity of the heterotrophic culture, described by kinetic tests, was dependent on pulsed phenol injection and on cyclic addition of phenol and TCE. Maximum TCE degradation was determined in a batch test. It was found that the addition of cycloheximide (an antibiotic against propagation and growth of fungi and yeast) increased the TCE degradation activity of the mixed microbial suspension. A certain residual amount of TCE remained in some of the experiments.  相似文献   
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