LAND RECLAMATION IS BASIC GUARANTEE OF REGIONAL SUSTAINABLE DEVELOPMENT IN COAL MINING AREAS IN CHINA

Necessity of land reclamation is discussed, setting out viewpoint of sustainable development and land connotation and its attribute and combining destroyed forms and characteristics of land in coal mining areas. It is pointed out that land reclamation of coal mining areas is basic guarantee of solving contradiction between coal mining areas and countryside,raising life of resident and ensuring regional sustainable development.

The environment of coal mining areas and the economic evaluation of the land reclamation

The environment impact of the coal resources mining was analyzed. The method of economic evaluation for the coal mining was established to analyze land destruction. The opportunity cost method was used to quantitatively analyze and estimate the economic loss of the land destruction by coal mining. At the same time, the dump land reclamation of the Yuanbaoshan Open Pit was taken as an example to evaluate environmental and economical benefit with the method of economic evaluation for the coal mining areas land reclamation.

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

Effects of mushroom waste on improvement of reclaimed soil qualityin coal mining areas

Restoring soil quality is the main evaluation norm of the reclamation. In order to reveal the effects of mushroom waste on the quality improvement of reclaimed soil in coal mining areas, the physical, chemical and microbial characteristics of soil are studied. The results show clear improvement in the soil after using mushroom waste. Because of human cultivation and fertilization, cultivated soil after reclamation exhibits high comprehensive quality and the index of quality of surface soil reaches 0.64 and 0.73. The average index of surface soil quality is as high as 0.52 and 0.54. In comparison, the quality of reclaimed soil of forest land is low, with average index of 0.40. The effects of mushroom waste are mainly on the surface soil in the first 2 years after the application. After that period, with the decomposition of mushroom waste, soil quality index tends to be the same as the original soil. The quality of surface soil is higher than that of subsoil, especially after the application of mushroom waste, at which point the soil quality reaches a peak at about 15 cm. Cultivated soil after reclamation has great variance in quality, after the coefficient of 24.74%. Mushroom waste can reduce such variation, particularly with long-term use. The variance efficient falls to 3.59% after 3-year application.

Impact of Sand Mining and Sea Reclamation on the Environment and Socioeconomic Activities of Ikate and Ilubirin Coastal Low Income Communities in Lagos Metropolis, Southwestern Nigeria

Land reclamation is gradually posing negative impact on man due to unplanned urbanization. A study was carried out on impact of land reclamation through sand mining of coastal communities in Ikate and Ilubirin in Lagos, Nigeria. Ten waters (8 surface and 2 groundwater sources), 10 soil samples and air were collected and taken for analysis. Results of water revealed concentrations lower than WHO (2017) and SON (2007) standards. Soil/sediment with average crustal value revealed Pb and Cd above standard values, which is attributed to anthropogenic influence on soils. Quality of air in the study was mainly particulate matter arising from the sea and reclaimed land in the surroundings of the environment with the highest Total Suspended Particulate of 0.8 mg/m3 in sulfur dioxide. This explains corrosion found on the roofs of the communities. Therefore, in the development planning adequate precautions should be put in place to avert environmental degradation.

Ecology economic mode of mining area and its way to realize

Practice has proved that if the traditional economic development mode of isolating exploitation of resources from environmental protection was adopted, or the land reclaim mode of managing after having been destroyed was taken, it is unable to solve the serious environmental problem of mining area effectively. According to the thought of sustainable development, the ecology economic mode of mining area-regard mining area as one three-dimension compound ecological economic system was put forward, and the exploitation and reconstruction activities were arranged, according to the objective rule of the whole operation of ecological economy, so as to make ecology economic system’s whole function optimize, the regional ecology harmonious and the pollutant be controlled in the whole course. It was discussed that the way to realize the ecology economic mode of mining area; the ecological programming of mining area on the basis of the cleaner production and green products strategy; the whole course controlling of ecological disruption based on the ecological industrial technology; the land reclaiming on ecological agricultural technology and the integration craft of exploitation of resources and ecology reconstruction of mining area based on the two integrated new technologies; and the technological system about the programming, monitoring, and appraising on exploitation of resources and the ecological reconstruction of mining area based on “3S” technology.

Distribution characteristics of available trace elements in soil from a reclaimed land in a mining area of north Shaanxi,China

Through field and laboratory tests we studied the temporal and spatial variation in the soil content of four available trace elements:copper(Cu),iron(Fe),manganese(Mn)and zinc(Zn),to analyze their distribution characteristics in reclaimed mining land under different reclamation conditions.The available trace elements content varied considerably with different land reclamation patterns.Extended reclamation time was helpful for the recovery of the available trace element content in the soil,and after more than eight years of soil reclamation,the content of available trace elements was closer to or greater than that in soil under natural conditions.Various treatment measures significantly influenced the content and distribution of available trace elements in the soil,and reasonable artificial treatments,including covering the soil and growing shrubs and herbaceous plants,increased the content of available trace elements.

Environmental issues from coal mining and their solutions

The environmental challenges from coal mining include coal mine accidents,land subsidence,damage to the water environment,mining waste disposal and air pollution.These are either environmental pollution or landscape change.A conceptual framework for solving mine environmental issues is proposed.Clean processes,or remediation measures,are designed to address environmental pollution.Restoration measures are proposed to handle landscape change.The total methane drainage from 56 Chinese high methane concentration coal mines is about 101.94 million cubic meters.Of this methane,19.32 million,35.58 million and 6.97 million cubic meters are utilized for electricity generation,civil fuel supplies and other industrial purposes,respectively.About 39% of the methane is emitted into the atmosphere.The production of coal mining wastes can be decreased 10% by reuse of mining wastes as underground fills,or by using the waste as fuel for power plants or for raw material to make bricks or other infrastructure materials.The proper use of mined land must be decided in terms of local physical and socio-economical conditions.In European countries more than 50% of previously mined lands are reclaimed as forest or grass lands.However,in China more than 70% of the mined lands are reclaimed for agricultural purposes because the large population and a shortage of farmlands make this necessary.Reconstruction of rural communities or native residential improvement is one environmental problem arising from mining.We suggest two ways to reconstruct a farmer's house in China.

煤矿区土壤细菌群落结构及其对不同复垦模式的响应

科学揭示不同复垦模式土壤细菌群落稳定性及其潜在互作关系对于复垦土地差异化管理及可持续利用至关重要。本文以挖深垫浅、煤矸石充填和粉煤灰充填3种模式复垦土壤为研究对象,基于高通量Illumina Miseq 16S rRNA测序技术,采用方差分析、Spearman相关性等分析方法,研究不同复垦模式下的土壤细菌群落结构和多样性。通过构建分子生态网络模型,揭示不同复垦模式下土壤细菌群落的稳定性及菌群间潜在互作关系,明晰对细菌群落结构稳定性起关键作用的微生物种群。结果表明:①不同复垦模式土壤细菌群落的多样性与丰富度水平有显著差异(P<0.05),均表现为挖深垫浅>煤矸石充填>粉煤灰充填;不同复垦模式土壤细菌群落组成相似,变形菌门、酸杆菌门、放线菌门和拟杆菌门是所有模式土壤中的优势菌门,在各复垦模式土壤细菌群落中的占比之和均达70%以上。②不同复垦模式下土壤细菌群落的显著影响因子不同,部分优势细菌门与影响因子间的变化趋势不同,有机质含量是影响挖深垫浅复垦土壤细菌群落组成的主要影响因素,pH是影响煤矸石与粉煤灰充填复垦土壤细菌群落组成的主要影响因素。③挖深垫浅复垦土壤细菌网络复杂,群落联系紧密,能更好地传递物质、能量和信息;煤矸石充填复垦土壤细菌网络内部节点间的连通度低,但菌群信息交换速度慢,拥有4个关键节点,网络相对稳定;粉煤灰充填复垦的土壤细菌网络规模最小,节点连通度不高,在外界环境发生变化时反应快,网络稳定性最差。3种复垦模式土壤细菌群落间关系均以协同合作为主导,煤矸石充填复垦土壤细菌群落间的协同合作关系占比最高。本文揭示了3种不同复垦模式下土壤细菌群落结构与分子生态网络差异,研究结果可为高潜水位采煤塌陷区土地复垦模式的优选以及人为干预方式的选择提供支撑。

基于时序InSAR的山西大同煤田地表沉降监测及时空演化分析

[研究目的]地表沉降作为煤矿区主要地质灾害之一,严重影响矿区经济的可持续发展和居民生活的安全稳定,有必要对矿区地表沉降进行快速高效监测。[研究方法]以大同煤田为例,研究使用2020年1月至2021年12月共31景Sentinel-1影像,基于短基线集干涉测量技术(Small Baseline Subset InSAR,SBAS-InSAR)对地表沉降进行监测,获取大同煤田地表沉降速率和累计沉降结果,使用已有研究成果对监测结果的可靠性进行验证,并分析了沉降时空变化特征及演化规律。[研究结果]大同煤田地表沉降分布较广,沉降总体分布趋势与大同煤田矿业管理数据的走向基本一致。沉降主要分布在大同市南郊区西部以及大同市、怀仁市和山阴县交界处,其中塔山矿地表沉降最为严重,大同煤田最大沉降速率为168.03 mm/a,最大累计沉降量为329.12 mm,总沉降面积为270.95 km^(2),且沉降呈现持续增加的趋势,根据沉降趋势推断需要较长时间才能实现地表活动相对稳定。[结论]研究表明了InSAR技术在煤矿区沉降监测的可行性,可为矿产资源管理工作提供新的技术方法,研究结果可为煤矿区沉降监测预警、灾害防控及资源合理开发利用提供科学依据。

我国矿区土地复垦关键政策实施情况调查分析

研究目的:调查土地复垦4项关键政策的实施情况,判断政策失灵与否,并分析其失灵原因,为相关政策修订提供科学支撑。研究方法:问卷调查法,统计分析法和定量分析法。研究结果:(1)三类受访者认为“谁损毁,谁复垦”政策不完善的比例为65.30%,其中第三方不完善比例高达92.02%,同时三类受访者一致赞同应由政府牵头复垦。(2)在编制土地复垦方案方面,三类受访者表示“不完善”(49.74%)略高于“赞成”(47.01%),其中第三方不完善的比例高达89.57%;矿山企业认为方案实施率较高,但政府部门(26.74%)和第三方(3.07%)表示方案落实不力。(3)矿山企业高度赞成采矿临时用地政策,但三类受访者一致认为政策执行率低,其中“0%执行”比例中政府为22.40%、矿山企业为23.92%、第三方高达91.41%,表明该政策执行率较低,需要改革和完善。(4)三类受访者赞成“边开采、边复垦”比例为43.59%、“不完善”为53.68%,其中第三方认为不完善的比例高达77.30%;政府和矿山企业都表示执行率较好,但第三方认为执行率仅为11.65%;政府(52.80%)和矿山企业(74.41%)不了解“边采边复”技术是政策实施不力的原因之一。研究结论:(1)“谁损毁,谁复垦”、编制“土地复垦方案”、“采矿临时用地”和“边开采,边复垦”4项关键政策的总体失灵度分别为51.11%、56.92%、89.23%和50.43%,均高于50%,同时第三方认为失灵度分别为92.03%、96.93%、98.77%和88.35%,表明4项政策都需要完善和革新;(2)4项政策均受到内部和外部多种因素的影响,导致执行率较低,需要从综合角度进行完善。

采煤沉陷区复垦对土壤细菌群落组装及固碳功能的影响——以东滩矿区为例

复垦能有效提升矿区生态服务功能,但复垦土壤功能重建的微生物学机制尚不清晰。厘清复垦如何影响土壤细菌群落特征、组装机制及固碳功能,对重塑矿区生态自维持能力至关重要。为此,结合零模型分析,采用MiSeq高通量测序及q PCR芯片技术,探索东滩矿区9 a、12 a、15 a和18 a等4个复垦年限土壤细菌群落组装过程及固碳功能变化。结果表明:(1)复垦和复垦时间对土壤理化和酶活性影响显著,复垦土壤pH、铵态氮(AN)、过氧化氢酶(CAT)及磷酸酶(PO)随复垦时间增长呈显著增加(P<0.05),有机碳(SOC)、有效磷(AP)、硝态氮(NN)及脲酶(UE)、β-葡萄糖苷酶(BG)、蛋白酶(PRO)则相反(P<0.05);(2)随机性过程主导了复垦土壤细菌群落的组装过程,且扩散限制的贡献最大;(3)有机碳、硝态氮、铵态氮、有效磷、β-葡萄糖苷酶及过氧化氢酶与碳循环功能基因丰度有显著性相关,复垦改善土壤理化从而增强固碳功能;(4)结构方程模型显示,复垦年限增加直接影响土壤理化性质,进而间接影响土壤微生物群落的组装过程,这可能是导致碳循环功能基因丰度变化的主要原因。研究结果为矿区复垦土壤生产力改善和固碳功能提升提供理论依据。

煤矿区土地复垦工程碳减排量核算体系构建研究

构建科学的碳源和碳汇核算体系对于准确评估我国土地复垦工程的碳减排效益至关重要。基于我国现行的土地复垦标准,对土地复垦工程类别进行了系统解析,并明确其具体内容及相关活动。根据国内外碳核算标准,识别出主要碳排放、碳汇的核算要素,选择了适合我国土地复垦工程的核算方法。对内蒙古准格尔某煤矿土地复垦工程的减排效果进行了评估,案例应用结果显示,煤矿区土地复垦主要包含5大工程类别,涉及4个重要碳排放要素以及4个碳汇要素。案例煤矿区复垦产生的碳排放量可抵消其碳汇量的15.94%。未来土地复垦工作应优化施工方案以减少碳排放量,同时应持续完善核算体系,以求精准跟踪土地复垦的实际减排效益,为土地复垦与碳管理提供有效支撑。

热湿地区矿山地质环境保护与土地复垦研究:以广东地区某水泥用石灰岩矿山为例

华南地区气候炎热多雨导致石灰岩地区土层浅薄、岩石蓄水能力弱、土壤贫瘠且环境较为干燥,这种缺乏土壤、水分和养分的环境不利于树木的根系生长。基于此,以位于典型热湿气候区的广东某水泥用石灰岩矿山为例,重点分析了矿区的地质灾害、含水层、地形地貌景观及水土环境污染等;同时,针对性提出了加强边坡稳定性勘查与监测、重视对含水层破坏的保护、重视对水土环境污染的预防等解决措施。

黄土丘陵沟壑区挖填造地工程勘察的探索与实践

黄土丘陵沟壑区挖填造地工程会遇到众多岩土工程问题。为保证类似工程建设的安全,避免相关工程事故的发生,依托某黄土丘陵沟壑区挖填造地工程实践,归纳了挖填造地工程前原场地勘察要点、研究方法和评价思路,分析了黄土丘陵沟壑区挖填造地工程面临的主要工程地质问题,并给出了建议措施。结果表明:填方区勘察重点为湿陷性黄土和其它覆盖土层的分布以及在高压力条件下工程性质,挖方区勘察重点为土石材料工程性质和土石比;主要工程地质问题涉及地下水环境变化及其对工程的影响、高填方场地沉降与不均匀沉降、填挖边坡稳定性、湿陷性黄土地基增湿变形、软弱淤积土地基问题、不良地质作用等。

基于无人机的人工植被分布识别与重建效果评价

人工植被重建是矿区土地复垦与生态修复的基础性工作,分析人工植被重建效果是评价生态修复质量的重要环节。以内蒙古蒙泰不连沟煤矿土地复垦示范区为主要研究区,采用无人机搭载多光谱相机进行数据采集,并应用3种常见的机器学习算法,综合地物光谱、纹理的差异提取人工植被。在此基础上,选取植被生物量指标,分析研究区坡顶人工植被生长状况,并评价其植被重建效果。研究结果表明,对机器学习分类方法进行超参数调优能够有效提升模型分类精度,超参数调优后随机森林分类模型分类精度最高,总体精度为82.11%,Kappa系数为0.77;使用随机森林模型获得的反演结果精度最高,其R^(2)为0.93,均方根误差为13.97。示范区坡顶的草本植被重建效果欠佳,有接近66.6%面积区域生物量等级处于0~50 g/m^(2)的范围;灌木重建效果较好,有接近61.4%面积区域生物量等级处于100~150 g/m^(2)的范围。

新疆某花岗岩矿地质环境特征及生态修复治理研究

矿产资源是社会发展的重要保障,近年来,随着国家对矿产资源需求的持续增长,矿业开采行业得到快速发展。矿山开采对周边地质环境影响较严重,矿山建设之前有必要对生态环境影响进行预测与评估。根据矿山生产建设规模评估,矿山生产及建设期间,采矿场、废石堆放场、办公生活区、荒料堆放场和矿山道路对土地将产生挖损和压占损毁,预测损毁土地面积合计48.75 hm^(2)。通过对矿山地质环境影响评估得出,预测评估矿山地质灾害的影响程度较轻-较严重;预测矿山开采对地形地貌景观影响严重-较严重-较轻。针对上述问题,在矿山开采和闭坑后,根据区域内的自然生态环境、社会经济发展等进行全面分析,充分考虑当地政府与民众对此提出的合理建议,依据土地复垦适宜性评价结果,结合工程土地复垦适宜性分析,对损毁土地的复垦采取砌体拆除工程、废弃物外运、削坡工程和平整工程等治理方案,实现防灾减灾和生态恢复的目的。

红层缓丘区造地工程设计与施工质量控制措施研究

土地资源的日益紧缺导致人工围海造地、削峰填谷等工程不断增多,造地工程在不同的地形地貌、工程地质条件下所面临着不同的工程技术难题。文章结合四川某红层缓丘区造地工程的实际情况,参考后期场地内建筑物的重要性程度,探讨了造地工程工后沉降控制标准、处治方法及施工质量控制措施,可为类似项目提供借鉴与参考。

土地复垦矿区的景观生态质量变化

为揭示土地复垦对矿区景观生态状况的影响,以徐州市贾汪矿区为例,运用RS、GIS和景观生态学方法,从生态系统稳定与干扰程度2个方面构建景观生态质量评价模型,并分析评价了该区的景观生态质量及变化。研究结果表明:2001-2010年间,贾汪矿区景观生态质量发生了明显变化,总体呈变好的趋势。2001年和2010年景观生态质量达到稳定和较稳定的面积分别为49994.86和56160.31hm2,2010年比2001年增加了6164.45hm2;从总体变化看,变好和略微变好的地区约占28.23%,主要分布在破坏较少的山区和煤矿复垦区,表明土地复垦工程对矿区生态环境起到了一定的改善作用。变差和略微变差的地区约占19.44%,表明部分地区生态环境质量仍在下降,主要由于城镇化的快速发展,煤炭开采的继续,环境保护措施不及时以及复垦地区的二次塌陷、治理标准低等原因。因此,需加大对生态脆弱区的环境保护,完善矿区复垦技术规程,制定生态修复策略,从而实现矿区土地的可持续发展。