煤矿区域环境影响评价有关问题探讨

本文结合煤矿区域开发的特点，论述了煤矿区域环境影响评价的作用，原则，基本内容及其应注意的问题。     

Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: A case study at Lihu, South China

Arsenic （As） pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As（III） accounts for 51.0% ± 9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As（III） and As（V） in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis （RDA）. Eight main factors, i.e., sediment iron （SFe）, sediment aluminum （SAI）, sediment calcium （SCa）, sediment organic matter （SOM）, sediment manganese （SMn）, water calcium （WCa^2＋）, water magnesium （WMg^2＋）, and water bicarbonate ion （WILCOX） were extracted from thirteen indicators. Their impacts on arsenic content rank as： SFe〉SCa〉WCa^2＋〉SAl〉wHCO3^-〉SMn〉SOM〉WMg^2＋. Of these factors, SFe, SAl, SCa, SOM, SMn, WMg^2＋ and WCa＆2＋ promote arsenic attenuation, whereas WHCO3^- inhibits it. Further investigation revealed that the redox potential （Eh） and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water.     

A review of environmental characteristics and effects of low-molecular weight organic acids in the surface ecosystem

Low molecular weight organic acids （LMWOAs） are prevalent on the earth＇s surface. They are vital intermediate products during metabolic pathways of organic matter and participate in the tricarboxylic acid cycle during life activities. Photochemical reactions are pivotal for LMWOAs＇ origination and play a large role in determining their diversity and their ultimate fate. Within the long time that organic matter is preserved in sediments, it can be decomposed and converted to release organic and inorganic pollutants as well as C, N, and P nutrients, which are of potential ecological risk in causing secondary pollution to lake water. The sediment pool is a comprehensive and complex compartment closely associated with overlying water by various biochemical processes, during which LMWOAs play critical roles to transport and transform elements. This article elucidates geochemical behaviors of LMWOAs in the surface environment in details, taking natural water, soil, and aerosol as examples, focusing on reviewing research developments on sources and characteristics, migration and mineralization of LMWOAs and relevant environmental effects. Simultaneously, this review article depicts the categories and contents of LMWOAs or their contribution to DOC in environmental media, and evaluates their importance during organic matter early diagenesis. Through concluding and discussing the conversion mechanisms and influencing factors, the next research orientations on LMWOAs in lake ecosystems are determined, mainly concerning relationships with hydrochemical parameters and microorganisms, and interactions with pollutants. This will enrich the knowledge on organic matter degradation and related environmental effects, and help reconstruct a theoretical framework for organic compound succession and influencing factors, providing basic data for lake eutrophication and ecological risk assessment, conducive to better control over water pollution and proper management of water quality.     

皖南新元古代双峰式岩墙群的年龄、地球化学特征及地质意义

皖南许村镇附近发育一套岩墙群,主要由辉长岩和花岗闪长斑岩组成,它们在时空上紧密伴生,成因上密切相关。岩石的SiO2含量集中分布在酸性和基性成分之间,缺乏中性及中酸性成分,构成一套双峰式侵入岩组合。对花岗闪长斑岩进行锆石LA-ICP-MS U-Pb年代学研究,表明双峰式岩墙侵入时间为822.1±6.6Ma。辉长岩具有正εHf(t)值(2.1~4.4)、大离子亲石元素和LREE富集,显示大陆拉斑质玄武岩地球化学和同位素组成特征;花岗闪长斑岩富含Zr、Hf和稀土元素,较高的Ga/A1比值,较低Ba、Sr、P、Ti含量,总体上地球化学特征类似A2-型花岗岩,εHf(t)值范围(1.8~4.6)与辉长岩基本相同。许村双峰式岩墙群的基性端员辉长岩是拉张环境下华南弱亏损岩石圈地幔部分熔融产生玄武质岩浆的产物,而酸性端员花岗闪长斑岩是玄武质岩浆在上升途中受地壳混染,并发生底侵作用和由玄武岩浆提供的热源导致地壳重熔的结果。     

土壤地球化学测量在赣东北良坑钼钨矿区勘查中的应用

良坑钼钨矿区位于赣东北断裂带南东侧、钦杭成矿带北部多金属成矿带内,成矿地质条件优越。文章研究良坑钼钨矿区的地质特征,分析该矿区的土壤地球化学异常,结合地形、地质及矿化特征等,共圈定6个综合异常。优选3个最有利的综合异常进行工程验证,发现数条钼矿体和钨矿体,取得了较好的找矿效果,拓展了赣东北断裂带南东侧找矿新领域,表明土壤地球化学测量在良坑钼钨矿区勘查中具有较好的应用效果,对赣东北断裂两侧进一步找矿具有一定参考。     

湖南郴州调研——区域环境矛盾应从生态补偿破题

由于空气环境污染的责任定性定量考核,在技术设备手段等方面还存在着短时期内难以解决的困难,当前制定生态补偿政策应以水环境污染主要污染物的量与浓度为基点,同比计算生态补偿额度,对污染地区进行补偿或者对污染治理与生态恢复成果进行奖励。     

趋势面分析法在环境领域中应用的评述及展望

随着现代科学技术的发展,各学科之间相互交叉、渗透,数学中的趋势面分析法在环境领域中的应用日渐广泛。趋势面分析法是一种可以有效地分析某一属性数据在空间上的分布规律和变化趋势的多元统计分析方法。文章在介绍了趋势面分析法的数学方法和原理的基础上,回顾和评述了趋势面分析法在环境领域中应用的范围和效果,总结了趋势面分析法在环境领域中应用的优势和不足,进而提出趋势面分析法与GIS技术相结合是一种解决相关环境问题的更为有效的方法,在区域污染研究中将发挥更重要的作用。