矿区的土地复垦工艺和技术

我国矿区每年都要破坏和侵占大量耕地，据统计，我国矿区每年排出废石渣约50Mt，堆放占用土地6667hm^2，全国1500多个露天煤矿及煤矸石占地就达200多万hm^2，但国土资源是有限的，解决一矛盾的最好方法就是开展土地复垦，保护现有耕地。     

矿区生态文明评价及预警模型研究

生态文明是人类在发展物质文明过程中保护和改善生态环境的成果。矿区是人类干扰破坏程度最大的区域之一,研究关于矿区生态文明的理论和评价方法等意义重大。在提出矿区生态文明概念基础上,参考国内外研究成果,建立了矿区生态文明建设评价指标体系。利用层次分析和模糊数学等方法,构建了矿区生态文明发展程度、协调发展度、协调发展动态指数等综合评价体系,并建立预警模型,为推进矿区生态文明建设提供参考。     

煤矸石综合利用途径的探讨

目前我国煤矸石综合利用途径主要有：做工业燃料、制砖瓦水泥等建筑材料及其制品、生产工业填料、做化工和稀有金属的矿物原料土地复垦填埋等。     

化学矿山开发中的废地复垦

对化学矿山废地复垦的政策问题、技术问题、管理问题和效益问题进行了阐述,并介绍了国内外矿山废地复垦方面的经验,提出了建设性的意见。     

鞍钢矿区重金属污染的植物修复技术研究

在对辽宁省鞍钢矿区土壤性质进行分析的基础上,阐述了矿区生态修复的必要性和植物修复技术的优势,提出了几种较好的可以用于该矿区土壤修复的植物种类,探讨了针对该区土壤特点的生物改良措施。最后,提出关于植物修复的后期处理,尤其是解决从植物体内回收重金属的生产工艺问题将是今后研究的热点之一。     

发展循环经济,建设绿色矿山

中国铝业股份有限公司广西分公司发展循环经济,建设绿色矿山,提高资源综合利用水平;严格处理"三废",积极复垦还地,避免浪费土地资源,保护生态环境,造福当地人民。其经验和做法为建设绿色矿山,发展矿业循环经济提供借鉴。     

绍兴市柯桥区生态文明建设国土空间现状、对策及措施

柯桥区经济发展已经迈入新台阶,生态文明建设水平不断提高,但同时也面临着土地资源紧缺、资源环境要素吃紧、国土空间合理开发等一系列问题和矛盾。现以柯桥区为例,对柯桥区生态文明建设规划国土空间章节编制情况进行说明研究。     

污泥用于生态恢复获突破

由南京市环保科学研究院承担的城市污水处理厂污泥用于宕口生态恢复示范项目，日前通过该市科技局和环保局联合组织的成果鉴定。专家认为，此项目开创了我国污水处理厂污泥资源化应用及矿山废弃．地宕口生态修复的全新模式。     

山东省“城市矿产”产业园区建设运营情况简析

经济与社会持续快速发展带来的原生资源日益短缺和环境污染严重现状,促使全社会高度重视"城市矿产"的开发利用。以具备产业聚集、土地集约、设施完备、生态环保特点的产业园区建设运营,推动"城市矿产"向着产业化经营、资源化利用和无害化处理的方向加快发展,是山东省近年来发展循环经济、建设生态文明的重要举措之一。重点介绍了山东省"城市矿产"产业园区建设运营的经验和做法以及今后的工作重点。     

瑞士绿色水电认证对我国水电开发评估的启示

简要介绍了EAWAG"绿色水电认证"的概念、程序和标准要求,分析了我国目前水电站评估中存在的制度上、技术上的缺陷和问题,结合"绿色水电认证"的特点,论证了该认证标准在我国水电站评估中的适宜性:绿色水电认证将管理计划与生态目标有机地结合,为我国水电评估指标体系的构建提供了十分有益的参考;通过绿色电力认证额外增加的发电量作为生态投资,强调电力的生态价值,提供资金改善受影响河道的生态完整性;绿色水电认证标准中关于生态监测的数据要求,能够填补我国目前水电站生态影响评价数据的不足.     

矿山生态修复方法及工程措施研究

矿山开采过程中对生态环境破坏极大,从而危及人类的生存与健康.开展矿山生态修复极为必要,对实现科学发展具有重要的现实意义.在叙述国内外矿山生态修复研究进展的基础上,介绍了目前矿山生态修复中的主要方法和工程措施,综合应用矿山生态修复技术,才能使矿山生态环境系统结构合理,功能完整,从而保证修复后矿山生态环境系统自然维持,达到矿山生态修复的目的.     

我国磷石膏处置现状及绿色发展对策

磷石膏的大量堆存不仅占用土地、浪费资源,存在巨大的环境和安全风险,更与我国无废城市发展理念相违背。本文系统梳理了近年来我国磷石膏产排现状、资源化利用现状和资源化利用途径。分析了磷石膏资源化所面临的问题和挑战,主要包括政策支持不配套、标准体系不完善、技术支撑不足和产品市场竞争力弱等。提出磷石膏绿色发展应从政策扶持、技术突破、完善标准、树立民众绿色消费意识等方面着手。     

Remediation of fly ash landfills through plantation

In India, a significant area of land is occupied by preexisting coal‐fired thermal power plants (TPPs) for the storage of fly ash slurry in ash ponds. However, the area available for storage of fly ash at these TPPs is limited. In addition, this type of fly ash disposal poses a problem due to restricted land availability and potential contamination issues. A viable alternative is the reclamation of fly ash ponds by plantation. A study at the Ramagundam Super Thermal Power Station (RSTPS) in Andhra Pradesh, India, on reclamation of a portion of an ash‐filled, low‐lying area has been performed. This article describes the characteristics of the RSTPS pond ash, ash leachates, and improvements in the fertility status of the reclaimed area over a three‐year period. Furthermore, morphometric observations of different planted species indicate that these types of ash‐filled, low‐lying areas can be suitably reclaimed and the nutrient‐rich leachate from ash‐filled areas potentially can be used for irrigation purposes. © 2008 Wiley Periodicals, Inc.     

Application of risk management techniques for the remediation of an old mining site in Greece

This article summarizes the project and risk management of a remediation/reclamation project in Lavrion, Greece. In Thoricos the disposal of mining and metallurgical wastes in the past resulted in the contamination with heavy metals and acid mine drainage. The objective of this reclamation project was to transform this coastal zone from a contaminated site to an area suitable for recreation purposes. A separate risk assessment study was performed to provide the basis of determining the relevant environmental contamination and to rate the alternative remedial schemes involved. The study used both existing data available from comprehensive studies, as well as newly collected field data. For considering environmental risk, the isolation and minimization of risk option was selected, and a reclamation scheme, based on environmental criteria, was applied which was comprised of in situ neutralization, stabilization and cover of the potentially acid generating wastes and contaminated soils with a low permeability geochemical barrier. Additional measures were specifically applied in the areas where highly sulphidic wastes existed constituting active acid generation sources, which included the encapsulation of wastes in HDPE liners installed on clay layers.     

Biogeochemical and ecological considerations in designing wetland treatment systems in post-mining landscapes

Although wetlands have gained acceptance as important components of ecosystems in post-mining landscapes in the past decade, their roles in contaminant retention/removal have not been well integrated into the designing of restoration programs. This paper describes the integration of sediment microbial activities and natural precipitation processes, along with approaches to defining the contaminant load from the mine wastes. The contaminant removal rates, which can be expected by a wetland sediment, are summarized and how they need to be reflected in the wetland size required, and the carbon supply which is needed. Contaminant loading from mining wastes can be balanced by wetland ecological processes, including wetland primary production and microbial mineralization in the sediment. This ecological engineering approach is demonstrated using case studies on hard-rock mining waste in Canada.     

Direct and Indirect Effects of Soil Pollution by Lignite Mining

Lignite mining and processing has caused a pronounced impact both directly and indirectly on soils and ecosystems across large areas of the former GDR. We studied soils of pine forest ecosystems at sites affected by severe alkaline dust and sulphur deposition, stemming from lignite fired power plant emission, and at dumped sites from lignite mining. In this paper we summarize our main results and evaluate the long-term impact of lignite mining and combustion on the environment. The pine ecosystems on naturally developed soils show a clear effect of deposition history along a former deposition gradient with distinct changes in chemical properties of organic surface layers and mineral soil as well as in element turnover and cycling rates. Afforested sites on mining dumps are directly affected by the composition of the dumped substrates. Over a large area (800 km²) these substrates are dominated by Tertiary sediments with varying amounts of lignitic particles and pyrite that result in phytotoxic site conditions (pH < 3, high salt and metal contents). High amelioration doses of liming material (up to 200 t ha⁻¹) were applied for restoration purposes. We studied the development of these sites over a period of 60 years using a false-time series approach. Beside the extreme soil conditions, element budgets of these sites are characterized by very high element release rates over decades caused by pyrite oxidation and primary mineral weathering.     

Biomass and Nutrient Dynamics of Restored Neotropical Forests

Restoring species-rich tropical forests is an important activity because it helps mitigate land deforestation and degradation. However, scientific understanding of the ecological processes responsible for forest restoration is poor. We review the literature to synthesize the current state of understanding of tropical forest restoration from a biogeochemical point of view. Aboveground biomass and soil carbon accumulation of restored tropical forests are a function of age, climate, and past land use. Restored forests in wet life zones accumulate more biomass than those in moist or dry life zones. Forests restored on degraded sites accumulate less aboveground biomass than forests restored on pastures or agricultural land. Rates of aboveground biomass accumulation in restored forests are lower than during natural succession, particularly during the first decades of forest establishment. Rates of litterfall, biomass production, soil carbon accumulation, and nutrient accumulation peak during the first few decades of restored forest establishment and decline in mature stages. Changes in species composition and canopy closure influence the rate of primary productivity of older restored stands. Species composition also influences the rate and concentration of nutrient return to the forest floor. The ratio of primary productivity to biomass is high in young restored forests and low in mature stands irrespective of climate. The ratio is low when past land use has little effect on biomass accumulation, and high when past land uses depresses biomass accumulation. This effect is due to a high rate of litterfall in restored forests, which helps restore soil by circulating more nutrients and biomass per unit biomass accumulated in the stand. The degree of site degradation and propagule availability dictates the establishment and growth of tree species. Reestablishment of forest conditions and the enrichment of sites by plant and animal species invasions lead to faster rates of succession, aboveground primary productivity, and biomass accumulation in restored forests. Our review demonstrates that nutrient cycling pathways and nutrient use efficiency are critical for interpreting the suitability of tree species to different conditions in forest stands undergoing restoration.     

Assessment of the use of spent copper slag for land reclamation.

The shortage of waste landfill space for waste disposal and the high demand for fill materials for land reclamation projects in Singapore have prompted a study on the feasibility of using spent copper slag as fill material in land reclamation. The physical and geotechnical properties of the spent copper slag were first assessed by laboratory tests, including hydraulic conductivity and shear strength tests. The physical and geotechnical properties were compared with those of conventional fill materials such as sands. The potential environmental impacts associated with the use of the spent copper slag for land reclamation were also evaluated by conducting laboratory tests including pH and Eh measurements, batch-leaching tests, acid neutralization capacity determination, and monitoring of long-term dissolution of the material. The spent copper slag was slightly alkaline, with pH 8.4 at a solid : water ratio of 1 : 1. The batch-leaching test results show that the concentrations of the regulated heavy metals leached from the material at pH 5.0 were significantly lower than the maximum concentrations for their toxicity limits referred by US EPA's Toxicity Characteristic Leaching Procedure (TCLP). It was also found that the material is unlikely to cause significant change in the redox condition of the subsurface environment over a long-term period. In terms of physical and geotechnical properties, the spent copper slag is a good fill material. In general, the spent copper slag is suitable to be used as a fill material for land reclamation.     

Development of a leaching assessment framework for the utilization of coal ash at South Korean mine reclamation sites

Coal-based power generates large quantities of coal ash in South Korea. However, coal ash recycling is still inactive and most wasted coal ash is buried in landfills. Recently, beneficial uses of coal ash such as in mine reclamation sites has been increasingly considered; however, as a result of legal limitations due to environmental concerns, the utilization of coal ash at mine reclamation sites has procrastinated. Consequently, to resolve this issue, the relevant environmental impact of coal ash must be considered. Therefore, a leaching assessment framework to assess the environmental impact of coal ash utilization at South Korean mine reclamation sites is presented. The framework was used to identify leaching mechanisms and support an assessment of the environmental impact of coal ash usage at mine reclamation sites in South Korea. This framework could provide guidance with regard to designing more realistic leaching procedures appropriate for all mine conditions and could support the development of regulations and protocols for future environment-friendly coal ash usage.     

Circular economy pattern of livestock manure management in Longyou,China

Journal of Material Cycles and Waste Management - The development of biogas programs in rural China has led to great economic, social, ecological and environmental benefits. The focus of this study...