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51.
煤矿区土壤有机碳含量测算与影响因素研究进展 总被引:2,自引:1,他引:2
研究矿区土壤有机碳的储量、影响因素以及时空变异规律,不仅对认识矿区土壤质量变化规律,而且对排土场覆土工艺和植被类型的选择具有重要的指导意义。植被、土壤质量等自然因素以及复垦管理措施、复垦模式等人为干扰会对矿区土壤有机碳的积累和转化造成重要影响。目前,对于矿区土壤有机碳的变化过程和转化机理的研究不够深入,尤其是土壤有机碳对复垦措施的响应规律鲜见报道。本文系统梳理了国内外学者对矿区土壤样品有机碳含量的测量和区域土壤有机碳储量的估算,自然因素、人为干扰对矿区土壤有机碳积累的影响。在此基础上,提出了深入研究的方向:1加强矿区土壤有机碳剖面结构的变化及其转化机制的研究;2加强对影响土壤有机碳积累的不确定因素的探讨研究;3应加强复垦模式及覆土工艺以及排土场微地形对土壤有机碳积累机理的研究。 相似文献
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复垦土壤母质原始形成环境及化学特征分析 总被引:2,自引:0,他引:2
平朔安太堡露天煤矿排土场的排弃物料,由第四系黄土、第三系红粘土及石炭系、二迭系泥岩、砂泥岩、砂岩等构成,粒度不均,大小不一,这些物质构成了复垦土壤的母质。由于沉积时期的地质环境不同,而且剥采剖面厚达150余米,这样深厚岩土层的化学性质,矿物和元素组成差异较大。本文采用勘探钻孔资料与剥离岩土化学元素分析相结合的方法,分析了复垦土壤母质来源的地质背景、化学性状、元素组成,为合理、有效地重构高质量的复垦土壤和恢复植被提供科学依据。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(9):981-1002
Abstract Four lignite overburdens from a potential lignite mining area of Louisiana were used to evaluate the effect of rates of fertilizer, lime, plant growth and simulated poor drainage conditions on the weathering of these materials. Common bermudagrass (Cynodon dactylon) grown on each overburden material in pots lined with polyethylene bags received 0, 1/2>x, 1x, 2x and 4x the recommended rate of fertilizer which was a combination of N, P and K. Lime was applied to the overburdens based on soil test lime requirement to increase the pH to 6.5. Enrichment (fertilizers, non‐drained conditions and lime) had a significant effect on the weathering of the overburdens. The pH, EC, organic C, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Na and Al were significantly affected by one or more of these parameters. Visual observations indicated that fertilizers stimulated root production, which effectively increased the weathering of the overburdens. Lime, applied as CaO, did not increase the pH of the Cow Bayou material substantially, suggesting the presence of pyrite, which was confirmed by X‐ray diffraction analysis. As pyrite oxidized in the Cow Bayou material, soluble salts accumulated on the surface of the material and on the lower parts of the plant. Gypsum and jarosite precipitated as the solution ionic strength of this material increased due to the weathering of the pyrite. The Prairie Terrace overburden was selected as the best potential topsoil since it had more favorable physical and chemical characteristics which would promote successful reclamation. Reduced materials such as Cow Bayou and Naborton had undesirable physical and chemical properties. Changes in the chemical properties of these materials would be difficult to predict and soil amendments such as lime and gypsum would be needed in significant quantities for successful reclamation. Dolet Hills, a sandy material, had a less desirable texture and would require frequent irrigation and fertilization if it were used as a topsoil substitute. 相似文献
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我国是一个矿产资源大国,丰富的矿产资源为我国的经济发展及生产建设提供了物质基础。可是我们在开采利用的过程中有不少盲目性,只着眼于眼前的短暂利益,而缺乏对矿山开采后的环境治理保护,致使矿山的生态失去平衡。本文以理塘县金厂沟金矿矿山为例,阐述了我国和四川省当前矿山开发产生的环境问题,并提出通过场地平整和草场恢复的方法,可使开采后的矿山环境得以改善。 相似文献
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永城市陈四楼煤矿土地复垦适宜性评价研究 总被引:5,自引:1,他引:4
为了采取指数和法和极限条件法对陈四楼煤矿土地复垦适宜性进行评价。以GIS软件为平台,利用河南省永城市土壤图、地形图、土地利用现状图进行空间叠加分析最终确定4个评价单元。依据研究区的自然、经济、社会现状和相关技术标准,确定了宜农、宜林、宜渔3个复垦方向的评价指标,然后采用指数和法和极限条件法对矿区复垦土地进行适宜性评价。结果表明:评价总面积为73.7 hm2,其中适宜农业种植用地面积为25 hm2,适宜林业种植用地面积为20 hm2,适宜渔业养殖用地面积为28.7 hm2。通过评价研究建立矿区土地复垦适宜性评价等级体系。 相似文献
60.
《Journal Of Applied Aquaculture》2013,25(1-2):159-172
Abstract This study involves a comprehensive economic analysis of mine water aquaculture. First, the costs and benefits are quantified using standard enterprise budgeting and feasibility techniques. Next, a price analysis is conducted to determine the underlying probability distribution and generate confidence intervals for use in planning purposes. Then, the relationships between mine sites and unemployment, and mine sites and tourism, respectively, are illustrated using a spatial analysis. Finally, the potential economic development impacts of growth in the aquaculture industry on statewide output, income, and employment are estimated. The results have implications for entrepreneurs and the aquaculture and coal industries in Appalachia and other parts of the US where coal mining can be linked to fish farming, water conservation, and recreation. 相似文献