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Surface runoff, erosion, compaction and the leaching of potential pollutants from land can degrade the soil resource and damage the water environment, reducing crop yields, causing loss of valuable nutrients and organic matter, together with increasing flood risk. Increasingly, it is recognized that scientific information must be translated into practical tools to change practices and protect the soil and water resource. Working alongside agencies in Scotland, we applied a suite of simple, transparent, rule-based models to identify areas most at risk of exporting sediment and pollutants that may degrade water quality based on field-scale (1:25,000) soil maps. The maps have been used by Scottish Environment Protection Agency, Scottish Water and Scottish Government to assess soil risks to waters from field to regional scale. The work brought scientists together with policy makers, agencies and the water industry to pool their knowledge to apply these practical tools for decision-making. It highlights the need to apply existing knowledge to answer salient questions. All three examples described show that providing the right type of information, which is based on fundamental soils data, can directly influence the implementation of policies, investment and monitoring decisions and provide evidence in support of government. However, this requires both researchers and agency scientists to develop skills as knowledge brokers and to normalize the use of soil data in everyday agency settings.  相似文献   
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坡面过程、块体移动和土壤侵蚀研究进展   总被引:1,自引:0,他引:1  
Soil erosion and land degradation are global problems and pose major issues in many countries.Both soil erosion and mass movement are two forms of land degradation and humans play important roles in these geomorphological processes.This paper reviews slope processes associated with mass movement and soil erosion and contributory factors,including physical and human agents.Acting together,these cause diverse geomorphological features.Slope processes are illustrated by reference to case studies from Brazil and UK.The causes and impacts of erosion are discussed,along with appropriate remedial bioengineering methods and the potential of the measures to prevent these types of environmental degradation.Although there are several agents of erosion,water is the most important one.Cultivation can promote soil erosion,due to ploughing and harvesting,which moves soil down slopes.Soil erosion and mass movement data would inform the viability of soil conservation practices.Integrated management of drainage basins offers a promising way forward for effective soil conservation and soil remedial bioengineering in Brazil and UK.  相似文献   
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李琰  魏翔  李红霞 《安徽农业科学》2011,39(31):19537-19539
当前我国农村民间金融发展速度快、规模大,但在其发展过程中存在着利率失控、潜伏着金融风险、容易产生经济纠纷等问题。针对这些问题,提出要明确民间金融的地位、规范农村民间金融、将民间金融纳入金融监管范围等政策建议。  相似文献   
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为获得碳汇收益与达成应对气候变化的目标,对碳汇林经营进行风险识别与管理具有重要的实践价值。通过实地调研与文献分析,发现碳汇林在经营过程中面临着自然风险、人为风险、政策风险与市场风险四大类风险。利用专家评分与层次分析法进一步对碳汇林面临的风险进行识别与评估,通过构造判断矩阵并利用MATLAB R2013b 进行分析,结果表明碳汇林经营中最主要的风险来自于政策风险(0.51)和市场风险(0.31)。对18 种具体风险因素进行综合总权重评估计算的结果表明,碳排放权交易政策(0.245)、碳市场价格(0.202)与森林碳汇交易政策(0.133)是对碳汇林经营影响最大的3 种风险因素。  相似文献   
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基于两变量Copula函数模拟、变点识别和均值平移时序重构方法,构建珠江三角洲西水东调工程受水区东江和水源区西江的枯水径流联合分布模型。以生态环境流量及最小流量管理目标为设计阈值,研究区域联合缺水风险特征及对变化环境的响应。结果表明:Archimedean copula的Clayton、Frank和GH模型,均能较好地模拟两区域枯水径流联合分布特征。变化环境下特别是流域内水利工程径流调节作用,东江枯水径流时序非一致性显著,均值跳跃明显,变点时间为1972年,最枯月径流量增加了65.5%。若要满足最小下泄流量管理目标,东江缺水风险率较高,为37.7%。与东江天然径流(还原系列)相比,在东江流域内水利工程影响下(还现系列),东、西江同时缺水风险率由35.8%下降到16.7%。但由于2江枯水径流的正相关性,西江有水可调保证率也由54.8%下降到21.0%。在已知东江缺水情形下,西江有水可调保证率(55.8%)仅略高于西江缺水风险率(44.2%)。因此,珠江三角洲西水东调工程运行,需要科学设计更为精细的水资源调度规则。  相似文献   
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农村城镇化生态风险法律规制的规范分析   总被引:1,自引:0,他引:1  
探讨如何在转型期的城镇化进程中,有效应对以生态风险为代表的各类风险,对当下的生态文明建设和绿色发展具有重要的现实意义。伴随着人口的聚集和工业的进驻,农村城镇化既会带来环境污染的不断累积,也会造成自然资源的大量耗费,同时也会占用大量的生态空间。基于对这些生态风险现状的分析,阐明我国在应对农村城镇化产生的污染累积性生态风险、资源耗竭性生态风险、生态空间占用性生态风险及复合型生态风险时,固然会受到经济社会等方面的影响,但更主要是因为出现了法律规制失灵的困境,存在着应对生态风险的法律法规体系不完善、司法救济效能有待提升、行政监管能力有待加强等滞碍因素。为有效规制城镇化生态风险,应以规范分析为进路,以法制生态化为方向,从完善生态立法,增强生态司法效能,提高生态执法能力等几个方面提出消解城镇化生态风险法律规制滞碍因素的具体对策。  相似文献   
9.
宝鸡市城郊农田土壤重金属污染风险评估   总被引:1,自引:1,他引:1  
为了揭示城市化和工业化等人为活动对土壤环境质量的影响,选择宝鸡市城郊结合部为研究区域,对土壤样品Cu、Zn、Pb、Cd和Cr等5种重金属进行了测定;采用单因子污染指数、综合污染指数法、地积累指数、内梅罗指数和H?kanson潜在生态危害指数对土壤重金属污染状况进行评价,同时运用潜在生态危害指数法分析研究了土壤重金属的潜在生态风险程度。结果表明:研究区域土壤中的5种重金属中除Cd的平均累计含量已超过国家土壤环境质量标准GB 15618—2008中的二级标准外,其他4种重金属元素的平均累计含量均未超过国家二级标准;内梅罗综合评价结果表明,宝鸡城郊农田土壤大多数采样点重金属污染处于尚清洁水平,S3和S5点处轻度污染,S7点中度污染,S6点为重污染;地积累指数评价结果,5种重金属的污染顺序为:Cd≥Cu≥Pb≥Zn≥Cr;5种重金属中Cd是生态风险最大,单个潜在生态危害程度为CdCu≥Pb≥Cr≥Zn;综合潜在生态危害评价显示,在S6和S7处综合为强生态危害,S3、S5和S10处中等生态危害,其余采样点处为轻微生态危害。源解析研究表明,研究区域土壤中的Pb、Cu、Cr和Zn来为同一污染源,而Cd为另外某一污染源。  相似文献   
10.
The scarcity of freshwater resources is a critical problem in semi-arid zones and marginal quality water is increasingly being used in agriculture. This paper aimed at evaluating the physico-chemical and biological risks on irrigated soils and fruits of macrophyte treated wastewater (TWW), the nutrients supply, and the effect on tomato and eggplant production in semi-arid Burkina Faso. During three years of experiments, treated wastewater was used, with fresh water as control, in combination with or without mineral fertilizer application at recommended rate (140 kg N/ha + 180 kg P2O5/ha + 180 kg K2O/ha). The study revealed that the treated wastewater provided variable nutrients supply depending on year and element. The treated wastewater without mineral fertilizer improved eggplant yield (40% in average) compared to the freshwater. Both crops responded better to mineral fertilizer (52% for tomato and 82% for eggplant) and the effects of the treated wastewater and fertilizer were additive. As the N supply of TWW was very unsteady (8-227% of crop need), and P2O5 supply did not satisfy in whole crop need (3-58%) during any of the three years of experiment, we recommended that moderate N and P2O5 fertilizers be applied when irrigating with TWW in semi-arid West-Africa. On the contrary, the K2O supply was more steady and close to crop requirement (78-126%) over the three years of experiment and no addition of K fertilizer may be needed when irrigated with TWW. Faecal coliforms and helminth eggs were observed in treated wastewater and irrigated soils at rate over the FAO and WHO recommended limits for vegetable to be eaten uncooked. Tomato fruits were observed to be faecal coliform contaminated with the direct on-foliage irrigation with treated wastewater. Our results indicate that treated wastewater can effectively be used as both nutrients source and crop water supply in market gardening in the semi-arid Sub-Saharan West Africa (SSWA) where freshwater and farm income are limiting. Yet consumers should properly cook or disinfect treated-wastewater irrigated vegetables before eating, and market gardeners should also be careful manipulating treated wastewater to avoid direct health contamination in this environment.  相似文献   
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