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991.
基于矿区废弃地植被恢复的视角,在分析矿区废弃地生态系统脆弱性和森林生态效益价值计量理论与方法的基础上,探讨了森林生态效益计量问题。结合矿区废弃地的相关特点,对矿区废弃地植被恢复中森林生态效益计量的具体指标进行了筛选。通过研究,选出涵养水源、净化大气、生物多样性保护、保持水土、游憩效益5个具体效益价值计量指标,为今后矿区废弃地植被恢复中森林生态效益价值的计量研究提供借鉴。  相似文献   
992.
经济发展导致矿业环境受到污染和破坏的趋势得不到遏制,其中很大原因是没有发挥民众的力量.因矿业环境的公众产品属性而彰显市场失灵,必须通过政府管制以弥补市场的不足.但是政府因信息滞后和官员寻租等现象而导致政府失灵,必须通过民众参与以监督政府.民众问责是监督政府矿业环境管制的主要形式,责任政府是应当接受问责的政府.拓宽问责渠道、创新社会管理、健全法律制度等是矿业社区民众问责政府的改革方向.  相似文献   
993.
采用柱淋溶实验模拟辽宁省红透山铜矿区土壤中重金属的淋溶迁移特征,研究了淋溶液pH、电导率(EC)和重金属含量的变化及其相关性,分析了重金属在淋溶前后的总量和形态变化,并初步探讨其生态与健康风险.结果表明,在1~3次淋溶中,淋溶液pH迅速下降,土样中的部分酸性物质被快速溶出,在第3次淋溶之后,淋溶液pH缓慢上升;淋溶初期淋溶液EC大幅度、迅速降低,此后随着淋溶次数的增加EC缓慢降低;Fe、Mn、Cu、As、Cd均能从土样中溶出进入淋溶液,其中Fe、Mn、Cu、As的溶出主要在淋溶初期,而Cd除了在初期有所溶出外,在淋溶后期还存在二次溶出释放阶段;淋溶后土样中绝大部分重金属总量均有所下降,各重金属的解吸率为Cd>As>Fe>Cu>Mn>Zn,其中以Cd、As含量下降最为明显,而Zn基本未溶出;淋溶前后土样中重金属的活性态(弱酸提取态(BCR-1)、可还原态(BCR-2)、可氧化态(BCR-3))含量发生了不同程度的变化,Fe的活性态含量在淋溶后变化很小,Mn、As的活性态含量在淋溶后有所上升,而Cu、Cd的活性态含量在淋溶后有所下降;随着淋溶的进行,土壤中各重金属的赋存形态发生了一定变化,从而可能引起其生态与健康风险的改变.  相似文献   
994.
The tin mining activities in the suburbs of Jos, Plateau State, Nigeria, have resulted in technical enhancement of the natural background radiation as well as higher activity concentrations of primordial radionuclides in the topsoil of mining sites and their environs. Several studies have considered the radiological human health risks of the mining activity; however, to our knowledge no documented study has investigated the radiological impacts on biota. Hence, an attempt is made to assess potential hazards using published data from the literature and the ERICA Tool. This paper considers the effects of mining and milling on terrestrial organisms like shrubs, large mammals, small burrowing mammals, birds (duck), arthropods (earth worm), grasses, and herbs. The dose rates and risk quotients to these organisms are computed using conservative values for activity concentrations of natural radionuclides reported in Bitsichi and Bukuru mining areas. The results suggest that grasses, herbs, lichens, bryophytes and shrubs receive total dose rates that are of potential concern. The effects of dose rates to specific indicator species of interest are highlighted and discussed. We conclude that further investigation and proper regulations should be set in place in order to reduce the risk posed by the tin mining activity on biota. This paper also presents a brief overview of the impact of mineral mining on biota based on documented literature for other countries.  相似文献   
995.
《Environmental Forensics》2013,14(4):255-269
This is the first in a three-article series in this volume of Environmental Forensics describing the framework that was developed to quantitatively allocate mass loading of metals to the Pinal Creek alluvial aquifer. This article describes geochemical fingerprinting, followed by spatial and temporal analysis of Pinal Creek monitoring well data (more than 600,000 records from hundreds of locations), which identified three distinct source areas and plumes on the basis of facility-specific differences in process geochemistry, ore mineralogy, and solution handling. The primary Webster Lake/Gulch source originated in 1926 (700 mg/L chlorine, 200 mg/L copper, 3000–9000 mg/L iron). Secondary contributions from the Bluebird/Oxhide/Live Oak Gulch/Davis Canyon leach complex in Upper Bloody Tanks Wash began circa 1962 (30–200 mg/L chlorine, 1500–3500 mg/L copper, <500 mg/L iron), and recent (1992–2001) contributions came from Miami Unit hydromining releases to Bloody Tanks Wash (30–70 mg/L chlorine, ~1000 mg/L copper, ~2000 mg/L iron). In Kiser Basin, where the plumes commingle, temporal evolution of the plume chemistry is reflected in a shift from a predominantly iron:copper-rich solution (10:1) to an increasingly copper-dominated signature (1:1) with the arrival of the secondary plume. Based on historical records and geochemical fingerprints, the original acid front migrated through the alluvium at ~0.5 m/day; however, later acidic releases traveled at ~2.3 m/day due to exhaustion of the available buffering capacity. The divisible nature of the plume supports quantitative allocation of contributions to the aquifer.  相似文献   
996.
中国城市矿产开发潜力、问题及对策研究   总被引:1,自引:0,他引:1  
城市矿产以开发城市废弃物中人类所需的各类矿产资源为目的,为解决中国面临的资源和环境问题提供了一个有效的解决方案。从中国城市矿产的开发现状着手,重点分析了中国城市矿产的开发潜力,并对当前城市矿产开发过程中面临的问题进行了讨论,最终提出了未来推动中国城市矿产有效开发利用的对策建议,以期对中国城市矿产的发展起到一定的积极意义。  相似文献   
997.
Mercury levels in sediment and predatory fish were measured for 53 localities in Suriname. The average mercury level in bottom sediment surpassed the Canadian standard for sediment in most localities, except the coastal plains. Of the predatory fish, 41 % had a mercury level above the European Union standard for human consumption of 0.5 μg g−1. Highest mercury levels were found in fish from the Brokopondo Reservoir and from the Upper Coppename River. High levels of mercury in fish in pristine areas are explained by atmospheric transportation of mercury with the northeastern trade winds followed by wet deposition. Contrary to gold mining areas, where mercury is bound to drifting sediments, in “pristine” areas the mercury is freely available for bio-accumulation and uptake. Impacts on piscivorous reptiles, birds, and mammals are unknown, but likely to be negative.  相似文献   
998.
Volatile organic compounds at swine facilities: A critical review   总被引:3,自引:0,他引:3  
Ni JQ  Robarge WP  Xiao C  Heber AJ 《Chemosphere》2012,89(7):769-788
Volatile organic compounds (VOCs) are regulated aerial pollutants that have environmental and health concerns. Swine operations produce and emit a complex mixture of VOCs with a wide range of molecular weights and a variety of physicochemical properties. Significant progress has been made in this area since the first experiment on VOCs at a swine facility in the early 1960s. A total of 47 research institutions in 15 North American, European, and Asian countries contributed to an increasing number of scientific publications. Nearly half of the research papers were published by U.S. institutions.Investigated major VOC sources included air inside swine barns, in headspaces of manure storages and composts, in open atmosphere above swine wastewater, and surrounding swine farms. They also included liquid swine manure and wastewater, and dusts inside and outside swine barns. Most of the sample analyses have been focusing on identification of VOC compounds and their relationship with odors. More than 500 VOCs have been identified. About 60% and 10% of the studies contributed to the quantification of VOC concentrations and emissions, respectively. The largest numbers of VOC compounds with reported concentrations in a single experimental study were 82 in air, 36 in manure, and 34 in dust samples.The relatively abundant VOC compounds that were quantified in at least two independent studies included acetic acid, butanoic acid (butyric acid), dimethyl disulfide, dimethyl sulfide, iso-valeric, p-cresol, propionic acid, skatole, trimethyl amine, and valeric acid in air. They included acetic acid, p-cresol, iso-butyric acid, butyric acid, indole, phenol, propionic acid, iso-valeric acid, and skatole in manure. In dust samples, they were acetic acid, propionic acid, butyric acid, valeric acid, p-cresol, hexanal, and decanal. Swine facility VOCs were preferentially bound to smaller-size dusts.Identification and quantification of VOCs were restricted by using instruments based on gas Chromatography (GC) and liquid chromatography (LC) with different detectors most of which require time-consuming procedures to obtain results. Various methodologies and technologies in sampling, sample preparation, and sample analysis have been used. Only four publications reported using GC based analyzers and PTR-MS (proton-transfer-reaction mass spectrometry) that allowed continuous VOC measurement. Because of this, the majority of experimental studies were only performed on limited numbers of air, manure, or dust samples. Many aerial VOCs had concentrations that were too low to be identified by the GC peaks.Although VOCs emitted from swine facilities have environmental concerns, only a few studies investigated VOC emission rates, which ranged from 3.0 to 176.5 mg d−1 kg−1 pig at swine finishing barns and from 2.3 to 45.2 g d−1 m−2 at manure storages. Similar to the other pollutants, spatial and temporal variations of aerial VOC concentrations and emissions existed and were significantly affected by manure management systems, barn structural designs, and ventilation rates.Scientific research in this area has been mainly driven by odor nuisance, instead of environment or health concerns. Compared with other aerial pollutants in animal agriculture, the current scientific knowledge about VOCs at swine facilities is still very limited and far from sufficient to develop reliable emission factors.  相似文献   
999.
基于淮北中湖采煤沉陷区2005年、2014年和2018年的遥感影像进行地表景观解译,研究治理前后该区景观格局变化特征及生态效应.结果表明:治理前,该区耕地破碎化加剧、景观优势最大并持续减弱,沉陷积水区水体呈聚集化趋势;治理后,景观基质由耕地变为水体,林地、草地面积显著增加且景观优势上升,人工湖泊水体聚集程度高.区域景观...  相似文献   
1000.
矿冶区周边水稻对不同来源重金属污染的指示作用   总被引:4,自引:1,他引:4  
有色金属开采与冶炼可对周边环境造成严重的重金属污染,查明重金属污染来源对于矿冶周边重金属污染管理与控制具有重要意义.为探索利用矿冶周边水稻对As、Cd、Pb、Zn和Cu的富集与水稻体内元素的含量平衡特征指示重金属污染来源的可行性,选择了我国著名的水口山Pb-Zn矿山开采与冶炼周边区,根据重金属污染排放和迁移扩散特征,结合当地气象和地貌条件,确定了3个典型采样区,其中两个采样区分别邻近冶炼厂和尾砂库,另一处为位于两者之间的过渡区.采用蛇形采样法在稻田内采集33个成熟水稻及土壤样品,分析水稻不同部位(包括根、茎叶、籽粒)及土壤中As、Cd、Pb、Zn、Cu5种重金属和其他16种元素的含量.结果表明,3个采样区之间土壤中的As、Cd、Pb、Zn和Cu含量均存在显著性差异;各采样区水稻中除根际和籽粒中Cd含量外,各部位重金属含量也均有显著差异.靠近冶炼厂的水稻茎叶中As、Pb含量高于离冶炼厂较远的采样区水稻茎叶.尽管As、Pb在靠近尾砂库采样区土壤中含量最高,但在该区水稻茎叶中的含量却最低;在除As、Cd、Pb、Zn、Cu5种重金属以外的其他16种元素中,水稻根部仅有5种元素含量在各采样区之间存在差异,指示相同的土地利用类型及土壤母质条件;而在茎叶和籽粒中则分别有多达11和10种元素含量出现采样区差异,指示重金属污染来源影响水稻茎叶及籽粒中元素的含量平衡.多元统计分析结果显示,3个采样区水稻茎叶中元素含量平衡存在显著的分异,显示出明显的采样区属性.结合采样区域空间位置、污染物来源、水稻对重金属的富集与转运特征分析,3个采样区重金属主要污染特征可分别确定为水-气混合来源型、大气来源型和尾砂来源型.论文结果证明利用水稻茎叶指示矿冶周边重金属污染来源是可行的.  相似文献   
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