地球化学勘查在宝兴沟—十五里桥找矿应用研究

2002年武警黄金第三支队在宝兴沟—依西肯一带开展了1∶10万水系沉积物测量工作,发现多处金异常,而后开展土壤地球化学测量,缩小找矿范围,再开展地表槽探工程揭露、深部钻探工程控制,最终发现了宝兴沟—十五里桥等大型金矿床。此项工作程序充分说明在大兴安岭高覆盖地区开展的水系沉积物和土壤地球化学测量工作方法有效,工作过程合理。     

影响富硒土壤产出富硒农产品的因素

[目的]根据不同地质背景的环境质量和产出富硒农产品的质量,评价不同研究区富硒农产品的优劣.[方法]研究了汕头市后坪、林招、金浦、兴平、东坑5个富硒土壤区Se的分布特征、成因来源以及所产出的富硒农产品,分析了研究区Se的迁移、转化和富集规律,按地质背景的不同分析了土壤有益元素、有毒有害元素的含量及其对农产品品质和富硒能力的影响.[结果]农产品的富硒主要受农产品类型、地质背景特征和土壤Se有效性的影响.[结论]农产品富硒的机制和Se的来源主要受不同地质背景下农产品对重金属元素吸收系数及营养元素含量高低的影响.     

Use of Soil Survey Mapping and Sampling for Determining Geochemistry of Regions

Abstract

The U.S. National Cooperative Soil Survey (NCSS) information about geographic distribution of soils is based on landforms and soil‐forming factors. A recent effort was initiated to determine the geochemistry of soils that are sampled as part of the routine NCSS work. The objectives of this article are to describe the mapping and site selection procedures, utility of these procedures in the geochemical analysis of soils, and the work and future direction of the Soil Geochemistry Program that was developed for this effort. This program was created within the U.S. Department of Agriculture, Natural Resources Conservation Service (USDA‐NRCS), for the purposes of instituting and monitoring the quality of laboratory geochemical methods and data, investigating the distribution of natural elemental concentrations in soils, and providing leadership in the application of geochemical data for NRCS. The soil survey has typically used the representative pedon concept as a basis for site selection, determined from the evaluation of soil morphology and component landforms within mapping units. The intent of this concept is to extend limited point data to geographic coverage. A geospatial database was compiled, containing major and trace element data for selected NCSS pedons. These data are provided with depth for major diagnostic horizons. Although initial geochemistry efforts have concentrated on benchmark soils to facilitate evaluation of source factors and broaden the utility of the data, this dataset includes both anthropogenic and nonanthropogenic soils. Future efforts require the investigation of geochemical variability of mapping units and the pedogenic redistribution of trace elements within soil landscapes.     

Assessment of soil contamination by potentially toxic elements in the aljustrel mining area in order to implement soil reclamation strategies

Land pollution due to past mining activities is a major environmental issue in many European countries. The Aljustrel mine (SW Portugal), located in the western sector of the Iberian Pyrite Belt (IBP) presents a negative visual and environmental impact as a consequence of the mining activity that has developed since the Roman era. Its impacts are also a restraint on the life quality of the population. The exposure of pyrite and other sulphides to air are responsible for the pollution observed in soils, surface water and stream sediments. This paper investigates the pollution load of potential toxic elements in soil samples collected around the Aljustrel mining area. The aim is to assess the levels of soil contamination with respect to average concentrations of toxic elements in the region and to understand the partitioning and availability of pollutants in the area. The results showed severe soil contamination (mainly As, Cd, Cu, Pb and Zn). The concentrations of As (up to 3936 mg kg⁻¹) and certain heavy metals (up to 5414 mg kg⁻¹ Cu, 61·6 mg kg⁻¹ Cd, 20 000 mg kg⁻¹ Pb and 20 000 mg kg⁻¹ Zn) are two orders of magnitude above the regional South Portuguese Zone (SPZ) background values. The median concentrations of As, Cd, Cu, Pb and Zn exceed the values established for world soils, the European Union, Portugal and Andalusia. The results suggest that the distribution patterns of Co, Cr and Ni element concentrations in the Aljustrel area are primarily influenced by the lithology and geochemistry nature of bedrock. The soil background of this geological domain is characterized by relatively high heavy metal contents, essentially derived from the parent rocks. Copyright © 2010 John Wiley & Sons, Ltd.     

农用地绿色产能评价体系构建及实证分析

绿色产能评价是农用地分等的进一步深化。该文在农用地分等成果基础上,结合土地质量地球化学评估,提出以产能评价、环境健康评价为主,有益元素、生态潜在风险为辅的综合性农用地评价方法,构建农用地绿色产能评价体系。最后选取吉林省西部4县（市）为研究区,进行农用地绿色产能评价,划定农用地绿色产能区。结果表明,研究区农用地总体质量良好,99.94%为绿色农田,其中绿色高产区主要分布在前郭东部和北部地区;镇赉南部及前郭北部地区有益元素丰富,大安北部及前郭西南部地区有益元素较缺乏;前郭东部地区农用地存在潜在风险,占总面积的1.5%。     

台风暴雨对热带林生态系统地球化学循环的影响

该文分析了９６１２号台风在海南尖峰岭热带山地雨林天然更新林集水区产生的暴雨径流过程及其水化学动态．结果得出：①总径流系数为３２．４２％,水文响应值为２３．１６％,瞬时最大洪峰流量为０．１１３５ｍ３·ｓ－１·ｈｍ－２;②因受海洋气团的影响,台风过程中该地降水的ｐＨ值、Ｋ和Ｃａ含量很高;③径流水中的ｐＨ及各养分动态变化趋势有两种相反的变化类型,一种是Ｎ,Ｐ,Ｃａ,Ｍｇ,Ａｌ元素,在降雨强度较大的暴雨期间,养分浓度大,且基本上随降雨强度的增大而增大．另一种是ｐＨ值、Ｋ和Ｓｉ元素,在暴雨期间,浓度随降雨强度的增强而减小,并在最大降雨强度时达到最低值;④台风暴雨能加速森林生态系统养分的丧失;⑤暴雨是热带地区普遍缺磷的一个重要原因;⑥在９６１２号台风暴雨过程中,养分的输入 输出变化表现为Ｎ,Ｍｇ,Ｃａ和Ｋ的输入大于输出,Ｐ,Ａｌ,Ｓｉ为输出大于输入．     

Salinization,alkalinization and sodification in Punjab (Pakistan): characterization of the geochemical and physical processes of degradation

Evidence of soil degradation impeding soil tillage and irrigation in cultivated soils in Pakistan is identified, described and represented in a general process of degradation. Based on a chemical analysis of soil characteristics, it is shown that a more general geochemical degradation process may occur in these soils. Two paths of salinization, i.e. neutral salinization and alkalinization inducing a process of sodification, are identified. The wide range of chemical properties of soils and corresponding geochemical processes can be explained by the great diversity of quality in irrigation water that is taken either from the canal or from the groundwater. The basic module of a geochemical model AQUA (Vallès and DeCockborne, 1992) is calibrated with the help of a study of the soil geochemical properties (identification of minerals, characterization of exchanges) and then used to assess the effect of four different water qualities on sandy and loamy soils. Based on these scenarios, the salinity, alkalinity and sodicity hazard of irrigation water is assessed by taking into account simultaneously the electrical conductivity and the residual alkalinity (calcite-residual alkalinity, residual sodium carbonates) or irrigation water and the soil cation exchange capacity: these three indicators appear the most relevant in the context of the study. Copyright © 1999 John Wiley & Sons, Ltd.     

廊坊市蓄滞洪区农业种植条件分析

适度开展工农业生产是当前蓄滞洪区经济可持续发展的重要途径,为指导农民充分、科学的运用土地、气候资源开展农业生产,减轻农民损失,维护农业用地及流域的生态环境安全,根据廊坊市国土农业地球化学调查成果和重点行业企业用地土壤污染调查资料,分析了土壤层和耕层的主要地球化学特征、气候特点及工业生产环境潜在污染风险,进行了农业种植区划：在保证行洪蓄洪要求的前提下,永定河泛区以瓜、果、油料、生态林种植为主,冲洪积湖积平原以粮、棉、菜、豆、牧草、速生林种植为主。同时指出区内企业应控制有毒粉尘的形成与扩散,遵照碳达峰、碳中和的目标要求尽快谋划转型升级。     

吉林省中部春、秋季玉米田土壤铅含量及其有效态转化空间特征比较

基于半变异函数与局部空间自相关方法,对吉林省中部地区春、秋季玉米田土壤铅元素的全量和有效态含量的空间特征进行比较。结果表明,研究春、秋季土壤铅元素超背景值样点比率分别为100%和93.55%,春季土壤未出现铅元素污染,秋季土壤样点铅元素污染比例为3.23%,秋季土壤铅元素的全量与有效量均值均大于春季土壤,铅元素呈累积活化趋势。半变异函数模拟参数显示,秋季铅元素全量C0/(C0+C)为强空间相关性,主要受随机因素影响;春季铅元素全量和有效量、秋季铅元素有效量C0/(C0+C)为中等空间相关性,受到区域性因素影响相对较强。春、秋季土壤铅元素全量之间及相应季节的全量与有效量之间的局部自相关类型空间分布差异较大,春、秋季铅元素有效量的聚集类型分布较一致。春、秋季土壤铅元素全量及有效量HH聚集区集中在吉林省中部和西南部,长春市与四平市附近玉米田土壤铅元素累积转化相对较明显,四平地区耕地土壤的铅元素输入量明显高于长春地区,铅元素全量的区域性输入变化未引起其有效态转化情况的明显变化。