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161.
A lack of resources for post-disaster housing reconstruction significantly limits the prospects for successful recovery. Following the earthquake in Wenchuan, China, in May 2008, housing reconstruction was not immune to resource shortages and price inflation. Difficulties in sourcing materials and labour considerably impeded recovery. This paper provides evidence of the resourcing bottlenecks inherent in the post-Wenchuan earthquake reconstruction process. Its aim is to present an integrated planning framework for managing resources for post-disaster housing rebuilding. The results are drawn from in-field surveys that highlight the areas where stakeholders need to concentrate effort, including revising legislation and policy, enhancing capacity for rebuilding in the construction industry, strengthening the transportation network, restructuring market mechanisms, and incorporating environmental considerations into overall planning. Although the case study presented here is country-specific, it is hoped that the findings provide a basis for future research to identify resourcing constraints and solutions in other disaster contexts.  相似文献   
162.
Large-scale column experiments were undertaken to evaluate the potential of in situ polymer mats to deliver oxygen into groundwater to induce biodegradation of the pesticides atrazine, terbutryn and fenamiphos contaminating groundwater in Perth, Western Australia. The polymer mats, composed of woven silicone (dimethylsiloxane) tubes and purged with air, were installed in 2-m-long flow-through soil columns. The polymer mats proved efficient in delivering dissolved oxygen to anaerobic groundwater. Dissolved oxygen concentrations increased from <0.2 mg l(-1) to approximately 4 mg l(-1). Degradation rates of atrazine in oxygenated groundwater were relatively high with a zero-order rate of 240-380 microg l(-1) or a first-order half-life of 0.35 days. Amendment with an additional carbon source showed no significant improvement in biodegradation rates, suggesting that organic carbon was not limiting biodegradation. Atrazine degradation rates estimated in the column experiments were similar to rates determined in laboratory culture experiments, using pure cultures of atrazine-mineralising bacteria. No significant degradation of terbutryn or fenamiphos was observed under the experimental conditions within the time frames of the study. Results from these experiments indicate that remediation of atrazine in a contaminated aquifer may be achievable by delivery of oxygen using an in situ polymer mat system.  相似文献   
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164.
Fertilization by phosphorus and also nitrogen fertilizers are the main source of cadmium soil contamination. Cadmium is relatively easily taken up by plants and then consequently enters their food chain. We investigated whether the cultivation medium with or without sulphates supplement affects the synthesis of protective low molecular mass thiols such as cysteine, reduced glutathione, oxidized glutathione and phytochelatins (PC2) in Dionaea muscipula treated with cadmium(II) ions at 0, 1, 5, 10, 25, 50, 100, 250, 500 and 1,000 μM for 6 weeks. The plants cultivated in the presence of sulphates showed higher cadmium tolerance due to faster growth and lesser number of necrosis hallmarks. Further, we utilized liquid chromatography with electrochemical detection for determination of the thiols in plant tissues. In the case of the plants cultivated on media supplemented with sulphates for 6 weeks the average PC2 level was 2,830 ng/g of fresh weight (FW). However, the plants cultivated on media without the presence of sulphates on average contained 1,160 ng PC2/g FW. Results obtained showed the positive effect of sulphur supplementation in cadmium detoxification processes in plants. In addition to thiol content, we also determined level of majority secondary metabolite of Venus flytrap, naphthoquinone plumbagin. Generally, the presence of sulphates in the media enhanced the protective mechanism and did not affect directly the synthesis of secondary metabolite plumbagin.  相似文献   
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166.
Little research has been performed on the impact of pesticides on earthworms under tropical conditions. Taking into consideration the often-limited resources in tropical countries, simple screening tests are needed. Therefore, it was investigated whether three pesticides relevant for the Brazilian Amazon (benomyl, carbendazim, lambda-cyhalothrin) affect the avoidance behavior of the earthworm Eisenia fetida. The tests were performed for two days according to ISO guideline 17512 but were adapted to tropical conditions (i.e. test substrate, test organism and temperature). The results indicate that this test gives reproducible and reliable results. Toxicity values (NOEC, EC50) are lower than those determined in 14 day-acute mortality tests and are approximately in the same range such as those found in 56 day-chronic reproduction tests with the same earthworm species, which were performed in parallel. Therefore, the use of the earthworm avoidance tests is recommended as a screening tool for the risk assessment of pesticides.  相似文献   
167.
This paper reviews and discusses the current literature relating to the drivers and barriers for a successful waste management curriculum at higher education level. The intention is to use this review to advise educational standards within the tertiary education sector so as to meet industry requirements. The paper presents a review of the UK's system for education and training within the waste management sector over the past decade, and discusses in what ways this approach could be successfully applied to the Australian sector. The paper concludes with a rationale for current research being undertaken within Australia, which seeks to identify which curriculum and pedagogic approaches are best suited for developing the skills of effective waste management practitioners both within the industry and for those graduating from higher education. The case made is that there is an absence of clear standards, educational provisions and certification for this growing industry within Australia, which inhibits the development of an effective waste management sector.  相似文献   
168.
During early development in fish, phospholipase A2 (EC 3.1.1.4) regulates membrane lipid modifications, which relates to changes in environmental conditions and provision of fatty acids required for metabolic energy substrates and prostaglandin biosynthesis. A method to analyze phospholipase A2 in rat tissues has been modified to measure its activity in embryonic Atlantic halibut (Hippoglossus hippoglossus L.). Egg and embryo samples were collected during the 1994 spawning season. Enzyme activity was undetectable at fertilization but in 10-d embryos was 230 pmol mg−1 h−1 (at 20 °C) and increased by ∼120% at hatch (17-d). Significant alterations in the fatty acid composition of important phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), were also observed. The content of some critical polyunsaturated fatty acids, and the ratio of unsaturated/saturated fatty acids, declined significantly over development. Acyl-chain restructuring mediated through the activity of phospholipase A2, coupled with other observed lipid changes (significant increases in the PC/PE ratio and cholesterol content), would produce a decreased fluidity of membranes during embryonic development, coinciding with the predicted upward movement of larvae in the water column. Arachidonic acid (20:4n-6) removed from PE could serve as a precursor for biosynthesis of 2-series prostaglandins, and eicosapentaenoic acid (20:5n-3) from PC is a likely source for other prostaglandin types. Despite removal of polyunsaturated fatty acids, there was an overall increase in lipid and fatty acid concentration, which can be attributed to amino acid catabolism during early developmental stages. Received: 9 September 1996 / Accepted: 8 September 1997  相似文献   
169.
Environmental Science and Pollution Research - During the cokemaking process, a significant amount of mercury occurring in a coal blend is released to the atmosphere. One of the ways of reducing...  相似文献   
170.
Carnivore predation on livestock is a complex management and policy challenge, yet it is also intrinsically an ecological interaction between predators and prey. Human–wildlife interactions occur in socioecological systems in which human and environmental processes are closely linked. However, underlying human–wildlife conflict and key to unpacking its complexity are concrete and identifiable ecological mechanisms that lead to predation events. To better understand how ecological theory accords with interactions between wild predators and domestic prey, we developed a framework to describe ecological drivers of predation on livestock. We based this framework on foundational ecological theory and current research on interactions between predators and domestic prey. We used this framework to examine ecological mechanisms (e.g., density-mediated effects, behaviorally mediated effects, and optimal foraging theory) through which specific management interventions operate, and we analyzed the ecological determinants of failure and success of management interventions in 3 case studies: snow leopards (Panthera uncia), wolves (Canis lupus), and cougars (Puma concolor). The varied, context-dependent successes and failures of the management interventions in these case studies demonstrated the utility of using an ecological framework to ground research and management of carnivore–livestock conflict. Mitigation of human–wildlife conflict appears to require an understanding of how fundamental ecological theories work within domestic predator–prey systems.  相似文献   
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