基于RS、GIS与AHP的巴音高勒小流域矿集区地质环境综合评价

针对矿产资源集约化利用区开展综合地质调查评价,建立了适用于小流域矿集区的矿山地质环境综合评价指标体系,利用遥感解译信息提取结合实际调查进行数据标准化处理,层次分析法确定指标层权重,GIS进行叠加矢量分析,以巴音高勒流域为例进行了矿山地质环境综合评价,划分矿山地质环境严重影响区、一般影响区、轻度影响区,表明该流域矿业开发造成的环境影响主要分布于矿床形成的自然异常区,即高背景区域内,为矿山地质环境监测预警、地质环境恢复治理与土地复垦、服务有色金属基地绿色矿业发展提供了科学依据。     

Ecological restoration of mineland with particular reference to the metalliferous mine wasteland in China: A review of research and practice

Despite a principal contributor to the rapid economic growth, the mining industry in China produced a large amount of wasteland and caused water pollution and soil erosion as well as other environmental damages. In 2002, this industry generated 265.4 Mt tailings, 130.4 Mt gangue and 107.8 Mt smelting slags. The degraded land associated with mining is estimated to be 3.2 Mha by the end of 2004, deteriorating the land shortage of China. Restoration of mine wasteland began in late 1970s but the restoration process was sluggish. The overall restoration rate (the ratio of reclaimed land area to the total degraded land area) of mine wasteland was some 10-12% with a higher rate for coal mine spoils but a lower rate for metal-mined derelict land. From 1994 to 2004, 149 research papers were published about the restoration of China's mining wasteland, of which 70 were on metal-mined land and 61 on the non-metal-mined land. Although 37 institutions in China were involved in the restoration research, only a few remained active and productive. Metal-mined derelict land is often more metal toxic and deficient of macronutrients and is tougher for revegetation. Many substrate amelioration techniques were proposed and tolerant plant species were tested for use of reclamation of the metal-mined tailings. Five hyperaccumulator species have been reported in China for the potential use in phytoremediation. However, these accomplishments were all at laboratory or small-scale field demonstration stage and still far from the practical use in reality. To accelerate the restoration and utilization of mine wasteland, several recommendations are put forward in this review. Above these suggestions, the commitment and efficiency of the government at all levels are vital.     

矿山地质灾害防治与土地复垦

通过分析矿山因开采而产生及诱发的地质灾害的类型、成因,分析了闭坑后潜在的灾害类型,结合矿山地质灾害防治与土地复垦的现状,提出了矿山开采和土地复垦同步进行的现代治理模式,以促进生态环境和社会经济的可持续发展。     

关于焦作市矿区废弃地复垦工程措施的探讨

结合焦作市矿区的地质情况,从土壤重构、植被重建、配套工程、监测与监管四方面阐述了该矿区废弃地复垦工程采取的措施,以期通过土地复垦工作促进该区域经济的持续发展和生态的良性循环。     

A national strategy for identification, prioritisation and management of pollution from abandoned non-coal mine sites in England and Wales. I.: Methodology development and initial results

In regions affected by historic non-coal (principally metal) mining activity, government agencies are often faced with the challenge of deploying limited remedial resources at abandoned mine sites to achieve maximum improvements in the chemical and ecological quality of impacted ground and surface waters. As such, strategies for the defensible allocation of public funds require comprehensive and systematic frameworks by which to identify and prioritise polluting sites for remediation. This paper describes the development and initial findings of such a national initiative in England and Wales which allies catchment-scale environmental impact assessments using existing public archive data, with recognition of the uncertainty in impact appraisals arising from disparities in data availability between sites and regions. The methodology identifies polluting sites and takes account not only of the chemical and ecological impacts of mine water discharges on receiving watercourses, but also of socio-economic factors such as conservation and heritage concerns, which can both impede or complement efforts to remediate mine sites. Using a Geographic Information System database and a suite of spatial analyses employing Boolean operators, both the extent of the pollution problem from abandoned non-coal mines in England and Wales (6% of 7815 surface water bodies are affected nationally) and the insight that can be gleaned from systematic analyses of existing archive data are highlighted. The results of the nationwide survey can be used as a dynamic database to inform future remedial planning, in terms of prioritising impacted river basins and abandoned non-coal mine sites themselves for either remediation or future monitoring efforts. As the assessment framework is built upon existing water quality and ecological data and mine site/geological data, there is considerable scope for the approach to be applied elsewhere where the legacy of historic mining persists through the widespread pollution of the aquatic environment.     

Effect of watershed parameters on mercury distribution in different environmental compartments in the Mobile Alabama River Basin, USA

Total mercury (THg) and mono-methylmercury (MeHg) levels in water, sediment, and largemouth bass (LMB) (Micropterus salmoides) were investigated at 52 sites draining contrasting land use/land cover and habitat types within the Mobile Alabama River Basin (MARB). Aqueous THg was positively associated with iron-rich suspended particles and highest in catchments impacted by agriculture. Sediment THg was positively associated with sediment organic mater and iron content, with the highest levels observed in smaller catchments influenced by wetlands, followed by those impacted by agriculture or mixed forest, agriculture, and wetlands. The lowest sediment THg levels were observed in main river channels, except for reaches impacted by coal mining. Sediment MeHg levels were a positive function of sediment THg and organic matter and aqueous nutrient levels. The highest levels occurred in agricultural catchments and those impacted by elevated sulfate levels associated with coal mining. Aqueous MeHg concentrations in main river channels were as high as those in smaller catchments impacted by agriculture or wetlands, suggesting these areas were sources to rivers. Elevated Hg levels in some LMB were observed across all types of land use and land cover, but factors such as shallow water depth, larger wetland catchment surface area, low aqueous potassium levels, and higher Chl a concentrations were associated with higher Hg burdens, particularly in the Coastal Plain province. It is suggested that the observed large variability in LMB Hg burdens is linked to fish displacement by anglers, differences in food web structure, and sediment biogeochemistry, with surficial sediment iron oxides buffering the flux of MeHg from sediments to deeper water pelagic food webs.     

煤矿区土地复垦中塌陷预测分析

首先分析了煤矿区地表塌陷原理,然后对煤矿区塌陷预测模型与方法进行了研究,并以河北省峰峰集团有限公司小屯煤矿为例,采用概率积分法进行了塌陷预测。结果表明,小屯矿扩大区拟塌陷破坏土地面积为560.95 hm2,为矿区土地复垦确定了复垦责任范围。     

高矿化度矿井废水深度处理及应用

同煤集团马脊梁煤矿的矿井废水处理工程采用预处理/双膜法工艺,出水水质达到饮用水标准,其运行成本为3.99元/m~3.对矿井废水进行回收再利用在水资源严重匮乏的矿区具有一定的推广价值.     

某矿山地质环境评估

通过对兴隆矿务局汪庄煤矿地理位置的描述,在充分收集有关资料及现场测绘的基础上,查明矿山开发及运营过程中可能引发和遭受的矿山环境问题,综合当地水文、自然等各方面条件的利用,进行了矿山土地资源环境与地貌景观现状、水资源现状以及矿山地质灾害评估,为制定有效的监测、处理方案提供指导。     

矿区自来水厂的"翻池"现象及对策

某矿区自来水厂在处理矿井尾水时出现了“翻池”现象,分析了产生“翻池”的原因,介绍了对原水进行混合、缓冲、稳流,增设流动电流与浊度双闭环加流量前馈控制的自动加药系统,投加助凝剂等一系列对策,以及达到的效果。     

煤层气田矿山地质环境保护与土地复垦方案探讨——以四川筠连煤层气田为例

在勘探、生产过程中,煤层气会对周边地质环境造成不良影响,需要开展地质环境保护与土地复垦工作。煤层气由于地理位置的特殊性,其矿山地质环境保护与土地复垦方案也有所不同。以四川筠连煤层气田为例,煤层气开采对地质环境的影响主要体现在地质灾害、含水层破坏、地形地貌景观破坏、水土环境污染及土地资源压占等方面。针对这5种地质环境影响,需要采取相应的监测工作,并根据土地利用现状和预测开展恢复治理工程等措施。文章论述和探讨了合理的煤层气田地质环境保护与土地复垦方案,以求为同类工作的开展提供借鉴和参考。     

采煤塌陷区土地复垦与重构土壤质量研究

中国人多地少,土地资源短缺,再加上每年因采煤塌陷的土地甚多,矿区人地关系矛盾突出。实施土地复垦工程是缓和矿区"矿—粮"矛盾的重要措施,同时也是建立稳定煤矿区生态系统的主要措施。本文在探讨矿区土地复垦技术的基础上,研究了复垦后重构土壤的质量演变。结果表明:现有的矿区土地复垦技术主要有非充填式复垦和充填式复垦两大类;重构土壤的容重、含水量、耕作阻力,以及土壤养分和污染性状等,与自然农业土壤相比均存在相异的发展过程。     

神东矿区矿井水综合利用研究

阐述了神东矿区矿井水开发利用中存在的问题,分析了矿井水的水质特征,探讨了矿井水资源化的处理技术、综合利用途径以及进一步提高矿井水资源综合利用的措施,指出神东矿区矿井水的资源化和综合利用具有显著的经济、社会和环境效益,是缓解其水资源用水矛盾、建立资源节约型矿区的必然选择。     

Environmental impact of mining activities on the surface water quality in Tibet: Gyama valley

Nearly 20 years of industrial scale metal mining operations in Tibet have caused an impact on the region's surface water quality. However, no information with respect to the pollution has been provided to the public. The aim of this work was to evaluate the chemical quality of the stream water and to assess the present and future potential risks of acid mine drainage to the regional and downstream environments.This study, based on data collected in 2006, 2007 and 2008 in the Gyama valley, using the Environmental Risk Index (I_ER) documents that elevated concentrations of Cu, Pb, Zn, Mn, Fe and Al in the surface water and streambed at the upper/middle part of the valley pose a considerably high risk to the local environment. In contrast, the risk level at the stream source area is zero and only minor risk at the lower reaches. The iron and copper contamination of the upper/middle part of the river appears to be both natural and accelerated by the mining activities. The level of dissolved contaminants in the water decreases within short distance downstream due to precipitation and sorption to the streambed and strong dilution by a tributary stream and eventually by the Lhasa River.A high content of heavy metals in the stream sediments as well as in a number of tailings with gangue and material from the ore processing, poses a great potential threat to the downstream water users. Environmental changes such as global warming or increased mining activity may increase the mobility of these pools of heavy metals.     

Back Analysis of Reclamation by Pump-Dredged Marine Clay—Influence of Ground Water Lowering—

When pump-dredged clays are discharged into a pond, suspended soil particles settle loosely to create sediments, which subsequently consolidate due to their own weight over a long period of time. In planning the capacity of such a disposal pond, it is important to estimate the time dependent volume change of dredged clays during the reclamation process. As the land thus created is extremely soft, ground improvement work is necessary if there exists a further plan of utilising the land. Predicting the soil profile of reclaimed land is absolutely necessary for designing the ground improvement. In this paper the authors i) outline the 18-year reclamation history of the Kanda Disposal Pond, ii) introduce a program to analyse self-weight consolidation under fully submerged condition, iii) modify the program to represent the suction effect due to ground water lowering, and iv) verify the applicability of the modified program by comparing the calculated results with the measured data.A simple analysis under fully submerged condition cannot explain the record of an 18-year reclamation, even if various combinations of consolidation parameters are used. The code modified to include the suction effect successfully simulates the actual behaviour when the appropriate parameters concerning the suction are chosen.     

Residual effects of lead and zinc mining on freshwater mussels in the Spring River Basin (Kansas, Missouri, and Oklahoma, USA)

Concentrations of selected trace elements in surface water and fluvial sediment were investigated as possible factors limiting the distribution and abundance of freshwater mussels in the Spring River Basin, a 6600 km(2) watershed overlapping a former Pb and Zn mining and ore processing district in the central USA. Mussel taxa richness surveys and supporting physical habitat assessments were performed in 23 stream reaches dispersed throughout the basin and above and below former mining sites. Quantitative mussel density surveys were performed in the Spring River at one upstream reference location and one downstream location. Concentrations of 16 trace elements in the soft tissues of mussels and Asian clams (Corbicula fluminea) were determined at most survey sites. Comparable analyses were performed on surface water samples collected during base flow and peak flow synoptic surveys and sediment samples collected during base flow periods. Sites on the Spring River immediately upstream of heavily mined areas supported at least 21-25 species of mussels, whereas sites near the lower terminus of the river yielded evidence of 6-8 extant species. Between the upper and lower quantitative survey sites, mean mussel and clam densities declined by 89% and 97%, respectively. Tributary reaches below heavily mined areas lacked evident bivalve communities and contained concentrations of Cd, Pb, and Zn that continually or sporadically exceeded hardness-dependent water quality criteria and consensus-based sediment quality guidelines (probable effect concentrations). In less contaminated stream reaches supporting bivalves, concentrations of Cd, Pb, and Zn in mussels and clams were correlated spatially with the levels occurring in surficial sediment (0.50 < or = tau < or = 0.64, p < or = 0.03). In non-headwater perennial stream reaches, sediment Cd, Pb, and Zn levels were related inversely to mussel taxa richness (-0.80 < or = tau < or = -0.64, p < or = 0.004). Metal contaminant burdens in mussels and clams fluctuated measurably in association with variable stream flow conditions and accompanying changes in surface water and sediment chemistry. Concentrations of Cd, Pb, and Zn in mussels approximately paralleled the levels measured in composite clam samples (0.74 < or = tau < or = 0.79, p<0.001), implying C. fluminea could serve as a possible surrogate for native mussels in future metal bioaccumulation studies. Overall, streams draining heavily mined areas exhibited depauperate (or fully extirpated) mussel assemblages and correspondingly elevated concentrations of Cd, Pb, and Zn in water, sediment, and bivalve tissue. Other evaluated environmental chemistry parameters, and physical habitat conditions assessed at the stream reach scale, demonstrated little general relationship to the degraded status of these assemblages. We conclude that pollution attributable to former mining operations continues to adversely influence environmental quality and impede the recovery of mussel communities in a large portion of the Spring River Basin.     

Stream water quality changes following timber harvest in a coastal plain swamp forest

The Goshen Swamp, a fourth order blackwater creek in southeastern North Carolina, was clearcut of 130 acres of riparian and seasonally flooded forest in late May through September 1998. Downstream water quality had been monitored monthly for 2 1/2 years before the clearcut, during the clearcut, and for two years following the clearcut. The objective of this paper was to test the hypothesis that clearcutting in the Goshen Swamp watershed negatively impacted downstream water quality. To do so, data from the Goshen Swamp were compared with data collected from a neighboring control creek (Six Runs Creek) of similar size, land use, and hydrologic characteristics. Compared with the control creek, the post-clearcut Goshen Swamp displayed significantly higher suspended solids, total nitrogen, total phosphorus, total Kjeldahl nitrogen and fecal coliform bacteria, and significantly lower dissolved oxygen over a 15 month period. Longer-term deleterious effects included recurrent nuisance algal blooms that had not been present during the 2 1/2 years before the clearcut. Although a 10 m uncut buffer zone was left streamside, this was insufficient to prevent the above impacts to stream water quality.     

Correlations between watershed and reservoir characteristics, and algal blooms in subtropical reservoirs

This study examined the correlations between watershed and reservoir characteristics, and water quality parameters related to algal blooms in seven subtropical reservoirs. Analysis of the dissimilarity of physico-chemical parameters resulted in separation of the reservoirs into three main groups: four reservoirs with the highest proportion of agriculture and/or urban land use in their watersheds; two reservoirs with a high proportion of forest cover; and one small reservoir with a relatively pristine watershed intermediate between the other two groups. All reservoirs were dominated by cyanobacteria, and at times, had species capable of producing toxins. However, the three reservoirs with the lowest percentage forest cover ( approximately 50%) had the highest frequency and magnitude of toxic species, principally Cylindrospermopsis raciborskii. Analysis of dissimilarity of algal species composition resulted in three reservoir groups similar to that for the physico-chemical parameters, with the exception of the reservoir with the highest percentage urban land use being an outlier. Across all reservoirs, percentage forest cover in the watershed, watershed area and reservoir volume were all significantly correlated with algal cell concentrations and total nitrogen (TN), but not with chlorophyll a concentrations. Total phosphorus (TP) was only correlated with the proportion forest cover in the watershed, suggesting that reservoir volume and depth were of less importance for TP than for algal cell concentrations or TN. These results suggest that watershed pattern and reservoir characteristics, such as water volume and depth, have a measurable effect on the type of algal blooms in reservoirs.     

真空加固超软土工艺的室内模型试验研究

吹填土是由含水率在80%以上的超软土形成。随着围海造陆的发展,吹填厚度越来越厚,土体压缩性非常大,因而在实际工程中出现了很多问题。在现场真空预压检测过程中发现只有土体表面2～3 m范围内土体强度明显提高,以下部分提高较小,通过延长加固时间也无法获得较好的加固效果。通过超软土真空预压室内模型试验发现加固后由于超软土发生很大的压缩变形,使排水板一定深度范围内发生了很大的扭曲变形,甚至发生局部折断现象,导致排水板失效或效率降低,从而使土体一定范围内加固效果欠佳。在加固土体变形基本稳定后,进行了二次插板再加固的试验,结果表明土体的沉降进一步发展,含水率进一步降低,十字板强度进一步提高,且十字板强度沿深度递减幅度大为减少。通过实验提出了对超软土地基进行二次加固的工艺,可使超软吹填土产生较好的加固效果。研究成果为探索更有效的加固深厚吹填土方法提供了依据。     

Limiting Imperviousness

Research shows negative consequences for a stream when more than 10 to 15% of the land in its watershed is covered by impervious surfaces. Yet we find that how imperviousness is measured has a major effect on whether such thresholds are exceeded. First we show large differences between estimates of impervious ness obtained with land use and land cover data, and propose adopting a consistent standard for the future. Second, we illustrate very different results when watershed imperviousness is measured at a few discrete points on the drainage system or continuously along all stream segments. Based on these findings we recommend that planners allow a safety margin when regulating land based on imperviousness, steer development towards already urbanized locations and away from relatively undisturbed locations, and take advantage of methods that mitigate the deleterious effects of imperviousness on stream ecology.