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1.
Nikki Baggaley Allan Lilly Kirsty Blackstock Karen Dobbie Adam Carson Fraser Leith 《Soil Use and Management》2020,36(1):19-26
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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P.B. Irénikatché Akponikpè Koffi WimaHamma Yacouba André Mermoud 《Agricultural Water Management》2011,98(5):834-840
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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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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我国远洋渔业的市场风险及对策分析 总被引:1,自引:1,他引:0
在远洋渔业规模不断扩大、产业结构调整、消费需求不断变化的背景下,我国的远洋渔业正面临着前所未有的挑战.以国内远洋渔业投入市场的水产品为对象,就价格风险、营销风险及竞争风险等3个主要方面,对远洋渔业所面临的市场风险进行综合分析,并提出相应的对策. 相似文献
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吉林西部查干湖湖泊沉积物中元素的空间变化及其环境意义 总被引:1,自引:0,他引:1
对吉林省西部查干湖湖泊沉积物中元素的空间分布特征及其潜在生态危害进行了研究。得出同吉林西部土壤中元素平均值相比,查干湖湖底表层底泥中明显富Ca、Cl、Mg、Hg、Cd,而贫K、U、Al、Co、Na、有机碳,其中Al2O3、MgO、Fe2O3、CaO、As、Hg、Cr、U、Cu、Zn、Cd、Se、Co、Ni、Th、Mn、N、P等主要来自岩石或土壤的风化作用,表层底泥中Hg、Cd、As、Cr、Cu、Zn、Pb的潜在生态危害性均很小;在湖泊沉积柱剖面中,Fe2O3、Cu、Zn、Co、Ni、Cr、Cd具有相同的变化趋势,不同沉积柱中沉积物具有相似的来源,沉积柱中重金属的潜在生态危害程度也很小,预示着在垂直方向上进入查干湖水体的重金属污染物数量也很少;查干湖的水体环境质量较好。 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