岩溶地区矿井水环境影响及防治对策探讨

岩溶地区矿井水对环境的影响复杂,它不仅对地表水体产生不利影响,而且由于落水洞、地下河发育,地下水体与地表水体之间水力联系密切,若矿井水若处置不当,还将对地下水环境产生不利影响.以典型的岩溶地区——贵州省金沙县为例,通过收集目前正常生产的部分矿井水水质资料,调查区域的基本水文状况,认为研究区地表水体规模普遍较小,落水洞、暗河等较为发育,地表水体与地下水体之间的水力联系较为密切,矿井水不仅容易污染地表水,而且容易对地下水产生不利影响.针对其影响方式、范围、程度及特点提出了源头控制、源头控制、矿井水资源化、优化排放方式等一系列的综合防治对策,以供类似地区矿井水的污染防治参考.     

某岛屿GF-1-RS浅层地下水富集性评估

为解决小尺度区域、缺水地区岛屿的浅层地下水富集性评估的相关问题,以岛屿为例,提出以GF-1与DEM等数据为数据源,选取岩性,地貌,坡度,植被覆盖度,地表温度,水域密度和土壤湿度,共7个指标进行提取,构建了该地区浅层地下水富集性遥感评估模型,得出了浅层地下水富集性等级图5级,并通过实测井中或泉水的水量对结果进行了验证。结果表明,评估结果满足误差精度要求,该方法能够对小尺度岛屿地区进行浅层地下水富集性评估。     

成像雷达干涉测量数据相关性与干旱-半干旱地区地表类型特征的关系

利用欧洲资源卫星1号和2号获取的重轨干涉测量雷达数据，首先进行干涉测量数据相关性估测，并结合干涉测量数据的振幅信息，开展新疆喀什试验区地表土地类型的识别与分类，区分和识别出裸土、盐碱地、灌丛、裸岩/戈壁、沼泽和水体 6类土地类型。最后通过对不同土地类型的后向散射特性和相关性的分析，探讨了干涉测量数据相关性与干旱-半干旱地区地表特征的关系。     

西部艰险地区水源地选址研究

为了在西部艰险地区实现军用水源地快速选址,选取地形、岩性、地貌及汇流累积量作为影响地下水富集的赋存条件因子,以土壤湿度、地表温度和植被覆盖度作为地表指示因子,以地貌作为军事防护因子进行研究。充分发挥利用遥感数据进行大范围水源地选址的优势,结合研究区地质资料进行图像解译和上述因子信息提取,建立具有不同层次结构的水源地选址评估指数模型。通过实地调查对模型进行验证,结果表明该评估指数模型预测结果可靠,适用于该地区军用水源地选址。     

包气带在干旱半干旱地区地下水补给研究中的应用

在干旱半干旱地区,包气带的溶质和同位素剖面不但可以提供较长时间尺度上的地下水补给信息,而且记录了过去气候变化与环境变化信息。本文基于学科组近10年的研究成果,以鄂尔多斯盆地为例（包括南部的黄土高原和北部的沙漠高原）,将包气带和饱和带结合起来,利用多种环境示踪技术,提升了包气带在干旱半干旱地区地下水研究中的潜力,并将其应用到地下水补给历史重建、地下水补给机制确定、植被变化对地下水补给影响评价和地下水污染物全过程示踪中。研究表明,由于在干旱半干旱地区,包气带较厚且补给量有限,地下水和现今的浅表水文过程未达到水力平衡,如在沙漠高原西部,近2 500 a降水尚储存在包气带13 m以浅,地下水是4 000 a以前补给的,其水化学特征与浅部包气带水差异巨大;而在黄土高原,补给量较大,但包气带巨厚,年降水仍需要几十到上百年时间入渗到地下水（但并不意味着没有补给,其土壤水在包气带中平均入渗速率为0.1~0.3 m·a-1）,包气带浅部溶质含量较深部和地下水中的高;典型黄土塬区的地下水均不含氚,地下水年龄在几百到上万年。黄土内部层状均匀的土壤质地特征和相对较老的地下水年龄揭示的均匀活塞流入渗是黄土塬区浅层地下水补给的主要方式。黄土高原退耕还林还草和沙漠区植被恢复导致地下水补给呈现不同程度的减少,反映在包气带上表现为溶质含量的增加,可用于定量化确定地下水补给量的变化。本文强化了包气带在干旱半干旱地区地下水补给研究中的作用,在未来地下水资源评价、地下水污染全过程刻画中应得到重视。     

辽宁省阜新地区地下水水质特征及污染防治措施

地下水水质特征和污染程度直接反映地下水环境质量的好坏。由于受工业“三废”、地表水体以及矿山固体废弃物排放等因素的影响,阜新地区地下水水质受到严重的污染,部分地下水化学指标已超出国家饮用水标准。文章综合分析该地区水文地质概况及水质特征,其中包括自然环境下地下水化学特征和人为环境下地下水化学特征,初步探讨了影响地下水污染的主要因素,并提出地下水污染的防治措施和对策,对该地区地下水资源合理开发、保护和可持续利用具有重要意义。     

面向生态的干旱半干旱地区区域地下水资源评价的方法体系

为了提高区域地下水资源评价的可靠性、扩展干旱半干旱地区面向生态的区域地下水资源评价方法,对准噶尔盆地和鄂尔多斯盆地地下水与生态环境关系进行调查研究,认为地下水具有重要的生态价值。目前在干旱半干旱地区区域地下水资源评价中对地下水的生态价值考虑不够,是造成地下水资源评价可靠性不高的原因之一。因此,提出了干旱半干旱地区地下水生态价值的概念,围绕可持续利用的地下水资源量与生态环境良性循环的目标,构建了面向生态的区域地下水资源评价方法体系。方法体系的基本思路是突出系统的观点和地表水与地下水统一评价、水质水量并重、地下水资源与其相关生态环境统一评价的3个原则;通过建立水文地质概念模型、集中参数型模型、分布参数型模型和基于地下水变化的生态环境综合评价4个模型,加上引进水量、水位与水质3个约束条件,以及开发基于GIS的地下水资源评价信息系统的平台,对地下水资源、调蓄能力与生态环境效益进行整体评价与预警。方法体系注重了地下水的资源和生态的双重属性,强调地下水资源与相关生态环境整体评价和预警的一体化,突出了模型体系与GIS技术在区域地下水资源评价和相关生态环境评价的有效集成。     

珠江三角洲地区地下水铁的分布特征及其成因

为了解珠江三角洲地区地下水中铁的含量及其成因,采集并分析了352组地下水样和12组地表水样。分析结果表明:珠江三角洲地区地下水铁含量为未检出～94.8mg/L,平均含量为1.46mg/L。该地区地下水铁含量的分布与其工业化程度及所处区域的补、径、排条件密切相关,尤其在平原区,地下水铁含量与部分地表河流的污染程度更是密切相关,随着远离污染的地表河流,地下水铁含量有明显减少的趋势。不同地区对其地下水铁含量起主导作用的因素也不相同,氧化还原条件是影响珠江三角洲地区地下水铁含量分布的主要因素之一,而酸碱条件和地面污染则只在局部地区对地下水铁含量的分布起主导作用。另外,含水层介质组分、径流条件、上覆土层性质等因素对珠江三角洲地区地下水铁含量也都起到了一定的作用。     

美国Sand Hills地区地下水数值模拟及水量平衡分析

利用地下水数值模型MODFLOW和非饱和带水平衡模型对处于半干旱半湿润沙丘地区(Sand Hills)地下水位进行了模拟,并分析了含水层补排水量,河流与地下水补排关系,以及区域水平衡过程。揭示了独特沙丘地形和土壤特性对地下水补排量的影响。模拟结果表明,入渗率大、非饱和带厚的沙丘有利于降水入渗补给,减少了地下水蒸散发损失。加上下覆含水层具有良好的地下水储水空间,是该地区储存丰富的地下水量,以维持河流稳定流量,供给众多湖泊和湿地的原因。该研究对我国地下水资源评价和生态环境脆弱地区水资源保护具有指导意义。     

陕北风沙滩地区面向生态的地下水可持续开发方案

陕北风沙滩地区地处干旱半干旱地区,矿产资源丰富,生态环境脆弱。地下水是区域内生产生活用水的主要来源,同时也是控制区内生态环境演化的重要因子。在查明该区域地下水补径排条件与生态环境关系的基础上,应用地下水流数值模拟技术,以地下水开发-生态环境响应-地下水调控为主线,分析了地下水开发方案下的生态环境响应,确定了区域地下水开发的合理阈限,为区域地下水开发利用与生态环境的良性发展提供技术支撑。     

内蒙古朱拉扎嘎金矿ETM+数据提取蚀变异常方法研究

中国西北部大部分地区属于荒漠景观区,自然条件恶劣,常规的地质、物探、化探找矿工作难度大,如何借助遥感技术进行矿产资源勘查,是地质工作者积极探索的方向之一。本次工作选择内蒙古阿拉善盟朱拉扎嘎金矿作为实验区,利用卫星遥感ETM⁺数据进行蚀变异常提取方法研究。从蚀变矿物的波谱特征出发,对Crosta法则进行改造,建立了适合本区的异常提取模型：铁化蚀变异常提取以Band 2、 Band 3 、Band 4 、Band 5/Band 1主成分分析为核心技术;含羟基和碳酸盐化蚀变异常提取以Band 2、Band 4、 Band 5 、Band 7主成分分析为核心技术。运用该模型完成了矿区及其外围蚀变异常提取工作,经过地面光谱验证,检测到铁化、含羟基和碳酸盐化蚀变矿物,认为提取方法合理,提取结果可信。本次研究工作可以为矿区外围找矿提供新方法,为推广和应用遥感技术在荒漠景观区找矿提供参考。     

Assessment of the effects of vegetation on soil erosion risk by water: a case of study of the Batta watershed in Tunisia

Soil erosion by water is a serious environmental problem which affects particularly the agriculture of developing countries. Due to specific factors, such as high rainfall intensity, steep slopes and vegetation scarcity, Tunisia is prone to soil erosion. Taking this into account, the main objective of this study was to estimate the soil erosion risk in the Batta watershed in Tunisia using qualitative and quantitative erosion model with remote sensing data and geographic information system (GIS). Moreover, a developed method that deals with evaluating the impact of vegetation on soil erosion by water is also applied. This method used multi-temporal satellite images with seasonal variability and the transformed soil adjusted vegetation index (TSAVI) which is appropriate in arid and semi-arid areas. For both erosion models, the results show that a large area of the Batta watershed is seriously affected by erosion. This potentially high risk is due especially to severe slopes, poor vegetation coverage and high soil erodibility in this watershed. Furthermore, the use of multi-temporal satellite images and vegetation index show that the effect of vegetation is a significant factor to protect the soil against erosion. The risk is especially serious in the summer season, but it decreases with the growth of vegetation cover in spring. Erosion model, combined with a GIS and remote sensing, is an adequate method to evaluate the soil erosion risk by water. The findings can be used by decision makers as a guideline to plan appropriate strategies for soil and water conservation practices.     

On the effect of moisture bonding forces in air-dry soils on threshold friction velocity of wind erosion

Wind erosion is a dominant geomorphological process in arid and semi-arid regions with major impacts on regional climate and desertification. The erosion process occurs when the wind speed exceeds a certain threshold value, which depends on a number of factors including surface soil moisture. The understanding and modelling of aeolian erosion requires a better understanding of the soil erodibility associated with different moisture conditions. In arid regions during the dry season, the atmospheric humidity plays an important role in determining the surface moisture content and the threshold shear velocity. By a series of wind tunnel tests and theoretical analyses, this dependence of threshold velocity on near surface air humidity is shown for three soils of different textures: sand, sandy loam, and clay loam. The results show that the threshold shear velocity decreases with increasing values of relative humidity for values of relative humidity between about 40% and 65%, while above and below this range the threshold shear velocity increases with air humidity. A theoretical framework is developed to explain these dependencies assuming an equilibrium between the surface soil moisture and the humidity of the overlying atmosphere. The conditions under which soil-atmosphere equilibrium occurs were tested experimentally in the laboratory for different soils in order to determine the effect of grain surface area and texture on the time required to reach equilibrium starting from different initial conditions.     

泾惠渠灌区土壤水分动态变化研究综述

在干旱、半干旱地区,水分是环境体系中最活跃的因素,植被对水分具有高度的依赖性,水分成为影响植物生存、生长发育的关键因素,对植被的稳定性生长与恢复重建具有极大的限制性。泾惠渠灌区位于陕西省关中平原中部,属大陆性半干旱气候区,该区降水时空分布不均,水资源短缺。从土壤水分的测试技术和土壤水分的动态变化研究方面进行综述,分析研究灌区2004～2007年四年土壤水分动态观测资料,得出研究区的土壤水分动态变化规律,同时简述水分有效性的研究进展,对提高农业干旱防御能力,制定节水灌溉计划,提高水分利用效率具有重要意义。     

科尔沁沙地典型区域地表环境变化与气候变化的响应关系

以科尔沁沙地阿古拉苏木为典型代表区域, 应用1987-2006年20 a间12幅遥感影像及相应气候数据, 分析了地表环境变化与气候变化间的响应关系, 提出了表征响应敏感程度、影响程度大小排序的气候因子影响指数(CFII). 结果表明: 近20 a研究区地表环境变化表现为不断恶化的趋势. 各类地表环境变化与气候因子变化间有着良好的响应关系, 各类气候因子变化以不同方式和过程不同程度地影响着地表环境的变化. 响应敏感度最大, 即对地表环境变化影响最大的是相对湿度, 其次为降水量和蒸发量. 水分条件是制约干旱半干旱地区地表环境变化的主导因素.     

Morphometric and hypsometric analysis in the Tierra Nueva Basin,San Luis Potosí, México

In areas with long periods of drought, it is essential to implement strategies to manage the available water resource. Tierra Nueva Basin is affected by this situation, consequently the farm production and livestock holdings are affected and the people don’t have access to enough water. In this paper, we propose an integrative methodology based on mathematical tools such as hypsometric and morphometric analysis applying geographic information systems. The proposal is strengthened with the aggregation of geological-structural, morphometrical, hypsometrical parameters and climatological information through a precipitation analysis provided by the National Water Commission from 1962 to 2010. According to the available data and the results obtained through the implemented proposal, an acceptable level of reliability is inferred allowing to determine areas structurally suitable for the use of surface water and its uptake. The methodology that we propose facilitates and simplifies the processes of searching and exploring locations suitable for surface water capture in arid and semi-arid zones, identifying in a qualitative and quantitative manner the optimal zone. For the case study, test-and-validation of the methodology the Tierra Nueva Basin in San Luis Potosí, México was selected. Tierra Nueva is a semi-arid site where “La Muñeca” dam is located. The results obtained in this work confirm the location of the “La Muñeca” dam as one of the most suitable areas for water collection. The methodology that we propose is a useful tool for the studies of water capturing purposes in arid and semi-arid zones.     

基于BMA多模型组合的疏勒河径流预测研究

准确可靠的径流预测对于水资源的科学管理与规划具有重要意义,特别是在水资源紧缺的干旱半干旱地区,径流预测对流域内水资源高效利用与水利工程经济运行具有重要现实意义。针对径流预测通常采用单一方法进行建模与预测,难以利用各预测模型优势的问题,本文利用极限学习机（ELM）模型、支持向量机（SVM）模型、多元自适应回归样条（MARS）等机器学习方法建立了疏勒河上游未来1~7日的径流预测模型。在此基础上,运用贝叶斯模型平均（BMA）方法对ELM、SVM、MARS模型的预测结果进行组合,构建了径流组合预测模型,以获取更可靠的预测结果,并采用蒙特卡洛抽样方法获取BMA的95%置信区间,对预测结果进行了不确定性分析。结果表明：ELM、SVM、MARS模型以及BMA组合模型均适用于干旱半干旱地区的中长期日径流预测;BMA的预测精度较单一模型更高,能够提供更准确的预测值;BMA的95%置信区间对实测值覆盖率高,同时能够提供较好的确定性预测和概率预测结果。表明BMA在资料有限的条件下,表现出较单一模型更高的预测性能,可以成为干旱半干旱地区中长期日径流预测的有效方法。     

锡林河流域地表水和浅层地下水的稳定同位素研究

2006年4—9月,在从锡林河源头沿河流进行地表水和地下水同位素样品采集和分析的基础上,利用全球降水同位素监测网(GNIP)包头站的大气降水稳定同位素资料,结合锡林河流域的气象和水文资料,对锡林河流域大气降水、地表水和地下水稳定同位素进行了研究.结果表明:地下水中δ18O和δD值分别集中在-11.7‰～-14.9‰和-80‰～-89.5‰范围内,δ18O沿地下水流向有增加的趋势,大部分地下水中δ18O的季节波动性不大;河流干流δ18O和δD的年算术平均值从源区的-12.8‰和-94.5‰到入锡林河水库处的-10.0‰和-79.3‰,差值分别约为3‰和15‰.河水中的δ18O值沿流程增加而增大的现象可归结为受含有较高δ18O值的地下水补给作用和河水的蒸发作用的共同影响,其中对δ18O蒸发富集的研究显示,蒸发引起δ18O富集值为1‰.通过地下水线(GWL)和地表水线(SWL)及区域大气降水线(LMWL)的对比分析发现,在径流季节,降水对地表水的贡献小,地下水是地表水主要的补给源,地表径流基本是地下水的排泄.     

A GIS-index integration approach to groundwater suitability zoning for irrigation purposes

In recent decades, the high population growth has increased the demand for agricultural lands and products. Groundwater offers reliability and flexibility in access to water for irrigation purposes, especially in arid and semi-arid areas, such as Amol-Babol Plain, Iran. However, the quality and quantity of groundwater may not be suitable for irrigation purposes in all areas due to urbanizations, and intensive agricultural and industrial activities. Groundwater suitability zoning for irrigation purposes could be useful to improve water resources and land use planning, mostly in areas with water scarcity. Therefore, a GIS-based indices method is proposed to assess suitable zones for agricultural activities, integrating the irrigation water quality (IWQ) index and hydrogeological factors. IWQ index was utilized to assess groundwater quality based on salinity hazard, infiltration hazard, specific ions, and trace elements hazards, and miscellaneous effects such as pH, bicarbonate, and nitrate. The potential of the aquifer for irrigation water abstraction was investigated using hydrogeological surveys such as slope angle of the plain, hydraulic conductivity, and aquifer thickness. The groundwater suitability index classified most of the study area (more than 90 %) as “excellent” or “good” suitability zones for irrigation purposes. A limited area of around 5.6 % of the total area has moderate suitability for irrigation purposes due to the Caspian Seawater intrusion and the presence of fossil saline water. The proposed methodology provides useful information in order to allow irrigation management to prevent water and soil deterioration.     

Groundwater exploration using remote sensing and geographic information systems in a semi-arid area (Southwest of Urmieh, Northwest of Iran)

Shortage of water required for drinking and agricultural uses is a subject with a vital importance in most arid and semi-arid regions. The area of this study is one of the semi-arid regions located in southwest of Urmieh lake, northwest of Iran, between N 37°00′, 37°15′ latitude and E 45°05′, 45°30′ longitude which is composed of Permian dolomitic limestone, limestone, and post-Jurassic granite with a very low primary porosity/permeability character. In order to delineate groundwater potential zones in this area, the study focused on identifying secondary porosity/permeability indicators such as lineaments, vegetation cover, lithology, drainage pattern, drainage density, etc. In this regard, a remote sensing and geographic information system-based methodology was selected. Landsat ETM, IRS (pan), SPOT data, digital elevation model, and digital image processing techniques such as filtering, false color composite, principal component analysis, band rationing and classification have been applied to reach the purposes. Information layers extracted for analysis and interpretation stage were then integrated with other data and modeled through the use of existing geographic information system (GIS) software and their related analytical functions. Finally, based on determined ground water favorability index for different sub zones, layers, weighting, and overlapping, a ground water potential index (GWPI) was defined which respectively was utilized to groundwater potential zoning and preparation of GWPI map of the region. Within the six different sub zones defined, two sub zones labeled with high and very good potential areas were highly recommended for further development and exploration purposes. Geophysical investigations in target areas confirm the labeled subzones. Based on the obtained results of the study, it can be concluded that remote sensing data are very useful tool to extract information of groundwater exploration. Also, application of geographic information systems to find target areas for groundwater exploration are effective to save time and cost.