中国污染场地土壤修复的现状与治理对策（以无锡市为例）

随着我国经济的持续快速发展,城市规模不断扩大,许多原来位于城区的污染企业从城市中心迁出,留下了大量的污染场地。本文概述了污染场地修复的现状与存在问题,并建议通过“六大体系建设”,加强场地污染的防治及修复。     

我国农田土壤重金属污染来源及特点

近年来,我国重金属污染日趋严重引起了人们广泛关注。本文概括了我国农田土壤重金属污染来源及特点,为我国农田重金属污染防治提供依据。     

Coupled Numerical Analysis of the Stability Behaviour of Unsaturated Soil Slopes Under Rainfall Conditions

Thebasicstressvariablesintheconstitutivemodelde velopedbyAlonsoetal[5] aresoilnetstressandsoilmatricsuctions ,whicharedefinedby　　　σ″ =σ -ua (1)　　　s=ua-uw (2 )whereσisthetotalstress,uwistheporewaterpressureanduaistheporeairpressure .　　Thenetmeanstresspanddeviatoricstressqarede finedas　　　p =σ1+2σ33-ua (3)　　　q =σ1-σ3(4 )　　Asgenerallyregarded ,thesoilsuctioniscomposedoftwoparts ,matricsuctionandosmosissuction .TheosmosissuctionisneglectedoriginallyinAlonsoetal′smodelandhe…     

Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area （SZIA）, China

Heavy metal contamination of soils, derived from sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides, and so on, has been of wide concern in the last several decades. The Shenyang Zhangshi Irrigation Area (SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years. This study investigated the spatial distribution and temporal variation of soil cadmium (Cd) and copper (Cu) contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods. The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils. The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil (LSGSS) in China, and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990. The contamination magnitude of soil Cd and the soil extent of Cd con- tamination had evidently increased since sewage irrigation ceased in 1992. The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil, but obviously decresed in subsoil. The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation. The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils.     

CLEA模型及其在中国应用典型案例剖析

为构建中国土地风险评价模型,介绍CLEA模型的暴露评估、毒性评估和风险表征方法.采用基本评价模式评价中国某示范区13种污染物,并对评价结果进行分析.提出借鉴CLEA模型中阈值效应本底暴露量的概念,完善中国土地利用风险评价模型的建议.     

膨润土修复矿区污染土壤的初探

绍兴某矿区土壤受重金属Pb和Zn的复合污染。本文研究了膨润土修复矿区污染土壤过程中不同pH、膨润土对污染土壤修复效果的影响。结果表明：pH、膨润土与污染土壤比是影响膨润土对Pb和Zn的吸附的主要因素,当pH=5．0时,吸附效果最佳。当pH=5．0,膨润土与污染土壤比=1：10时,平衡液中Pb和Zn的浓度比不添加膨润土分别降低44％和58％。膨润土与污染土壤比=1：5时修复效果最好。因此,在pH在5,膨润土与污染土壤比=1：5时,可以达到最好的修复效果,膨润土可以用于修复被Pb和Zn污染的土壤。     

用石灰处理膨胀土路基填料

膨胀土在低压时遇水会发生体积膨胀,失水时会发生体积收缩,对膨胀土路基进行处理是保证路基稳定工作的常用工程措施之一。本文介绍了膨胀土工程性质对公路工程的危害以及膨胀土的石灰处治方法,对不同石灰掺加剂量的实验结果进行了分析,并提出了石灰处理膨胀土的施工工艺及注意事项。     

太湖地区几种水稻土的有机碳储存及其分布特性

选择了采自江苏省吴县市的黄泥土、乌泥土、白土等太湖地区代表性水稻土 ,测定了土壤有机碳的剖面分布、易氧化性碳分异、在土壤团聚体中的分布及 13 C稳定性同位素的剖面分异 .结果表明太湖地区水稻土中有机碳储量达 7～ 10 kg/m2 ,有机碳主要分布于 2～ 0 .2 5mm和 0 .2 5～0 .0 2 mm两级团聚体中 ,各土壤间有机碳的氧化活泼性接近 ,稳定性同位素组成类似 ,说明其有机碳地球化学性质趋向于与当前 C- 3农作物利用状况相平衡 .     

几种水稻土对磷的吸附及解吸特性研究

水稻土对磷的吸附曲线与简单Ｌａｎｇｍｕｉｒ等温吸附方程基本吻合,土壤对磷的吸附及解吸能力主要受土壤物理性粘粒含量及土壤活性铁、活性铝含量的影响,而与土壤本身有效磷含量无关。同一种水稻土随吸附磷量的增加,其解吸率有增加的趋势     

化学淋洗法修复重金属污染土壤效果研究

在国内外相关研究的基础上,文章研究化学淋洗修复技术在重金属污染土壤修复方面的运用．用浓酸消解土样并用火焰原子吸收法测定土壤中重金属含量,选用土壤柱作淋洗实验,分析去离子水和EDTA溶液两种淋洗剂对Cu、Zn、Pb、Cd四种重金属的淋洗效率,并对化学淋洗修复效果进行比较．