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81.
饮料盒工业做出承诺改进其资源利用和环境性能.他们已经确定了工业链的某个或多个环节的其体的部门优先考虑事宜:森林资源的可持续管理、保护生物多样性、在整个过程中减少能源利用以支持削减二氧化碳排放、减少工厂和运输方面的大气排放、减少水的利用和排放、减少化学品和有害物质、回收和再利用废旧森林资源.该产业采取生命周期手段来解决从森林到回收再利用的业务管理问题.该产业的代表协会饮料盒与环境联盟(ACE)参与了联合国环境署的生命周期举措.ACE认为这一举措对于生命周期全球思想的发展和传播是必不可少的.  相似文献   
82.
Conflicts between the interests of agriculture and wildlife conservation are a major threat to biodiversity and human well-being globally. Addressing such conflicts requires a thorough understanding of the impacts associated with living alongside protected wildlife. Despite this, most studies reporting on human–wildlife impacts and the strategies used to mitigate them focus on a single species, thus oversimplifying often complex systems of human–wildlife interactions. We sought to characterize the spatiotemporal patterns of impacts by multiple co-occurring species on agricultural livelihoods in the eastern Okavango Delta Panhandle in northern Botswana through the use of a database of 3264 wildlife-incident reports recorded from 2009 to 2015 by the Department of Wildlife and National Parks. Eight species (African elephants [Loxodonta africana], hippopotamuses [Hippopotamus amphibious], lions [Panthera leo], cheetah [Acinonyx jubatus], African wild dogs [Lycaon pictus], hyenas [Crocuta crocuta], leopards [Panthera pardus], and crocodiles [Crocodylus niloticus]) appeared on incident reports, of which 56.5% were attributed to elephants. Most species were associated with only 1 type of damage (i.e., either crop damage or livestock loss). Carnivores were primarily implicated in incident reports related to livestock loss, particularly toward the end of the dry season (May–October). In contrast, herbivores were associated with crop-loss incidents during the wet season (November–April). Our results illustrate how local communities can face distinct livelihood challenges from different species at different times of the year. Such a multispecies assessment has important implications for the design of conservation interventions aimed at addressing the costs of living with wildlife and thereby mitigation of the underlying conservation conflict. Our spatiotemporal, multispecies approach is widely applicable to other regions where sustainable and long-term solutions to conservation conflicts are needed for local communities and biodiversity.  相似文献   
83.
Tidal flats are a globally distributed coastal ecosystem important for supporting biodiversity and ecosystem services. Local to continental-scale studies have documented rapid loss of tidal habitat driven by human impacts, but assessments of progress in their conservation are lacking. With an internally consistent estimate of distribution and change, based on Landsat satellite imagery, now available for the world's tidal flats, we examined tidal flat representation in protected areas (PAs) and human pressure on tidal flats. We determined tidal flat representation and its net change in PAs by spatially overlaying tidal flat maps with the World Database of Protected Areas. Similarly, we overlaid the most recent distribution map of tidal flats (2014–2016) with the human modification map (HMc) (range from 0, no human pressure, to 1, very high human pressure) to estimate the human pressure exerted on this ecosystem. Sixty-eight percent of the current extent of tidal flats is subject to moderate to very high human pressure (HMc > 0.1), but 31% of tidal flat extent occurred in PAs, far exceeding PA coverage of the marine (6%) and terrestrial (13%) realms. Net change of tidal flat extent inside PAs was similar to tidal flat net change outside PAs from 1999 to 2016. Substantial shortfalls in protection of tidal flats occurred across Asia, where large intertidal extents coincided with high to very high human pressure (HMc > 0.4–1.0) and net tidal flat losses up to 86.4 km² (95% CI 83.9–89.0) occurred inside individual PAs in the study period. Taken together, our results show substantial progress in PA designation for tidal flats globally, but that PA status alone does not prevent all habitat loss. Safeguarding the world's tidal flats will thus require deeper understanding of the factors that govern their dynamics and effective policy that promotes holistic coastal and catchment management strategies.  相似文献   
84.
Aquifer sediment and groundwater chemistry data from 15 Department of Defense facilities located throughout the United States were collected and analyzed with the goal of estimating the amount of natural organic carbon needed to initiate reductive dechlorination in groundwater systems. Aquifer sediments were analyzed for hydroxylamine and NaOH‐extractable organic carbon, yielding a probable underestimate of potentially bioavailable organic carbon (PBOC). Aquifer sediments were also analyzed for total organic carbon (TOC) using an elemental combustion analyzer, yielding a probable overestimate of bioavailable carbon. Concentrations of PBOC correlated linearly with TOC with a slope near one. However, concentrations of PBOC were consistently five to ten times lower than TOC. When mean concentrations of dissolved oxygen observed at each site were plotted versus PBOC, it showed that anoxic conditions were initiated at approximately 200 mg/kg of PBOC. Similarly, the accumulation of reductive dechlorination daughter products relative to parent compounds increased at a PBOC concentration of approximately 200 mg/kg. Concentrations of total hydrolysable amino acids (THAA) in sediments also increased at approximately 200 mg/kg, and bioassays showed that sediment CO2 production correlated positively with THAA. The results of this study provide an estimate for threshold amounts of bioavailable carbon present in aquifer sediments (approximately 200 mg/kg of PBOC; approximately 1,000 to 2,000 mg/kg of TOC) needed to support reductive dechlorination in groundwater systems. © 2012 Wiley Periodicals, Inc.  相似文献   
85.
Rates of trichloroethene (TCE) mass transformed by naturally occurring biodegradation processes in a fractured rock aquifer underlying a former Naval Air Warfare Center (NAWC) site in West Trenton, New Jersey, were estimated. The methodology included (1) dividing the site into eight elements of equal size and vertically integrating observed concentrations of two daughter products of TCE biodegradation—cis‐dichloroethene (cis‐DCE) and chloride—using water chemistry data from a network of 88 observation wells; (2) summing the molar mass of cis‐DCE, the first biodegradation product of TCE, to provide a probable underestimate of reductive biodegradation of TCE, (3) summing the molar mass of chloride, the final product of chlorinated ethene degradation, to provide a probable overestimate of overall biodegradation. Finally, lower and higher estimates of aquifer porosities and groundwater residence times were used to estimate a range of overall transformation rates. The highest TCE transformation rates estimated using this procedure for the combined overburden and bedrock aquifers was 945 kg/yr, and the lowest was 37 kg/yr. However, hydrologic considerations suggest that approximately 100 to 500 kg/yr is the probable range for overall TCE transformation rates in this system. Estimated rates of TCE transformation were much higher in shallow overburden sediments (approximately 100 to 500 kg/yr) than in the deeper bedrock aquifer (approximately 20 to 0.15 kg/yr), which reflects the higher porosity and higher contaminant mass present in the overburden. By way of comparison, pump‐and‐treat operations at the NAWC site are estimated to have removed between 1,073 and 1,565 kg/yr of TCE between 1996 and 2009. © 2012 Wiley Periodicals, Inc.*  相似文献   
86.
Fitzpatrick MC  Preisser EL  Porter A  Elkinton J  Waller LA  Carlin BP  Ellison AM 《Ecology》2010,91(12):3448-55; discussion 3503-14
The study of ecological boundaries and their dynamics is of fundamental importance to much of ecology, biogeography, and evolution. Over the past two decades, boundary analysis (of which wombling is a subfield) has received considerable research attention, resulting in multiple approaches for the quantification of ecological boundaries. Nonetheless, few methods have been developed that can simultaneously (1) analyze spatially homogenized data sets (i.e., areal data in the form of polygons rather than point-reference data); (2) account for spatial structure in these data and uncertainty associated with them; and (3) objectively assign probabilities to boundaries once detected. Here we describe the application of a Bayesian hierarchical framework for boundary detection developed in public health, which addresses these issues but which has seen limited application in ecology. As examples, we analyze simulated spread data and the historic pattern of spread of an invasive species, the hemlock woolly adelgid (Adelges tsugae), using county-level summaries of the year of first reported infestation and several covariates potentially important to influencing the observed spread dynamics. Bayesian areal wombling is a promising approach for analyzing ecological boundaries and dynamics related to changes in the distributions of native and invasive species.  相似文献   
87.
Key attributes of the source zone and the expanding dissolved plume at a trichloroethene (TCE) site in Australia were evaluated using trends in groundwater monitoring data along with data from on-line volatile organic compound (VOC) samplers and passive flux meters (PFMs) deployed in selected wells. These data indicate that: (1) residual TCE source mass in the saturated zone, estimated using two innovative techniques, is small ( 10 kg), which is also reflected in small source mass discharge ( 3 g/day); (2) the plume is disconnecting, based on TCE concentration contours and TCE fluxes in wells along a longitudinal transect; (3) there is minimal biodegradation, based on TCE mass discharge of  6 g/day at a plume control plane  175 m from source, which is also consistent with aerobic geochemical conditions observed in the plume; and (4) residual TCE in the vadose zone provides episodic inputs of TCE mass to the plume during infiltration/recharge events. TCE flux data also suggest that the small residual TCE source mass is present in the low-permeability zones, thus making source treatment difficult. Our analysis, based on a synthesis of the archived data and new data, suggests that source treatment is unwarranted, and that containment of the large TCE plume ( 1.2 km long,  0.3 km wide; 17 m deep;  2000–2500 kg TCE mass) or institutional controls, along with a long-term flux monitoring program, might be necessary. The flux-based site management approach outlined in this paper provides a novel way of looking beyond the complexities of groundwater contamination in heterogeneous domains, to make intelligent and informed site decisions based on strategic measurement of the appropriate metrics.  相似文献   
88.
Contributing to the worldwide biodiversity crisis are emerging infectious diseases, which can lead to extirpations and extinctions of hosts. For example, the infectious fungal pathogen Batrachochytrium dendrobatidis (Bd) is associated with worldwide amphibian population declines and extinctions. Sensitivity to Bd varies with species, season, and life stage. However, there is little information on whether sensitivity to Bd differs among populations, which is essential for understanding Bd‐infection dynamics and for formulating conservation strategies. We experimentally investigated intraspecific differences in host sensitivity to Bd across 10 populations of wood frogs (Lithobates sylvaticus) raised from eggs to metamorphosis. We exposed the post‐metamorphic wood frogs to Bd and monitored survival for 30 days under controlled laboratory conditions. Populations differed in overall survival and mortality rate. Infection load also differed among populations but was not correlated with population differences in risk of mortality. Such population‐level variation in sensitivity to Bd may result in reservoir populations that may be a source for the transmission of Bd to other sensitive populations or species. Alternatively, remnant populations that are less sensitive to Bd could serve as sources for recolonization after epidemic events.  相似文献   
89.
The demand for processes to clean up contaminated soils without introducing additional contaminants is increasing. One approach to solving this problem is the use of supercritical fluids like carbon dioxide, alone or with cosolvents, to extract contaminants from the soil. Carbon dioxide is readily available, inexpensive, and nonpolluting. Gases exhibit unique properties under supercritical conditions. They retain the ability to diffuse through the interstitial spaces of solid materials, plus they have the solvating power of liquids. Soil cleanup using supercritical fluid extraction (SFE) is being investigated as an alternative/complementary technology to other cleanup methods such as incineration and bioremediation. The objective of the studies included in this article was to collect and analyze data to support use of the SFE technology and to provide the conceptual design and operational processes needed for building a portable treatment unit.  相似文献   
90.
D Brown  RS Thompson 《Chemosphere》1982,11(4):427-435
Mussels (Mytilus edulis) were exposed to di-2-ethylhexyl phthalate (DEHP) and to di-isodecyl phthalate (DIDP) over a period of 28 days. The bioconcentration factor (BCF) as measured by 14C analysis, reached estimated plateau levels corresponding to mean BCF values of approximately 2500 and 3500 for the DEHP and DIDP respectively. The mussels were then held in clean seawater for a further 14 days and 14C analysis showed a depuration half-life of approximately 3.5 days for both phthalates. During the whole 42 days of the experiment general observations on the health of the animals showed no evidence of any adverse effects.  相似文献   
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