房地产用地土壤污染环境风险评价——以江苏某搬迁企业原址用地为例

许多房地产项目都是在工业企业原址上进行开发建设,可能存在不同程度的土壤污染。土壤污染的评估和修复方案已成为房地产开发项目环评的重点,文中采用单因子指数法、内梅罗指数法和土壤背景值对照法对江苏某房地产用地土壤进行了环境风险评价,结果表明该地块不需要进行土壤修复和处置。     

Preparation and performance of arsenate (V) adsorbents derived from concrete wastes

Solid adsorbent materials, prepared from waste cement powder and concrete sludge were assessed for removal of arsenic in the form of arsenic (As(V)) from water. All the materials exhibited arsenic removal capacity when added to distilled water containing 10–700 mg/L arsenic. The arsenic removal isotherms were expressed by the Langmuir type equations, and the highest removal capacity was observed for the adsorbent prepared from concrete sludge with heat treatment at 105 °C, the maximum removal capacity being 175 mg-As(V)/g. Based on changes in arsenic and calcium ion concentrations, and solution pH, the removal mechanism for arsenic was considered to involve the precipitation of calcium arsenate, Ca₃(AsO₄)₂. The enhanced removal of arsenic for the adsorbent prepared from concrete sludge with heat treatment was thought to reflect ion exchange by ettringite. The prepared adsorbents, derived from waste cement and concrete using simple procedures, may offer a cost effective approach for arsenic removal and clean-up of contaminated waters, especially in developing countries.     

The Coastal Environmental Characteristics of Taiwan

Abstract

There are three major factors affecting the coastal environment in Taiwan: tidal current, long-shore current and land subsidence. in Taiwan, most industrial areas are located on the southwestern coast. Most of the pollutants from the factories are discharged directly to the ocean, harbours or rivers. the pollutants in harbours or rivers will eventually be delivered to coastal waters. There, the tidal current is the major force dispersing the pollutants nearshore. the polluted water extends to an area about 5 km on both sides from the discharge source, and within about 3–4 km off-shore. in this study, Hsien-Da Harbour in southwestern Taiwan is cited to explain the effects of tidal current on the coastal environment. the long-shore current induced by breaking waves is the major force shaping the coastal morphology. Along the western coast of Taiwan, the long-shore current mainly flows northward along the southern section, and southward along the northern section. in the last one hundred years, in general, the coast has been eroded along the northern and southern sections of western coast, and some reclaimed lands were formed in the middle section. Recently, erosion in some coastal zones is quite serious because of excess groundwater extraction, especially along the southwestern coast. Groundwater extraction might also induce land subsidence. There are some areas near the coast which suffer serious land subsidence problems.     

The Declining Influence of Science On Marine Environmental Policy

Abstract

Differences between the scientific and environmental policy communities regarding marine environmental protection strategies are discussed in the context of the nature and extent of scientific influence on marine environmental policy. Public perceptions of the nature and severity of marine pollution frequently differ from scientific assessments. the thesis of this paper is that the increasing influence of public perception on marine environmental protection policy is leading to the adoption of simplistic and unnecessarily extreme approaches to marine pollution prevention and to a reduced reliance on science. This trend is illustrated by some recent international developments and some suggestions are made towards enhancing the influence of science on marine protection policy.     

四川省环境污染经济损失与污染治理投资比例探讨

环境保护同经济建设和社会发展相协调,是我国环境保护的基本原则。本文从环境保护与经济发展的相互关系出发,比较实际地估计了我省各种污染排放物及造成的经济损失,探讨了环保治理资金社会投入的比例问题。     

ECONOMIC POLICIES FOR REGULATING AGRICULTURAL DRAINAGE WATER1

ABSTRACT: Agricultural drainage water is a major source of environmental pollution in many areas. This paper reviews the literature on the economics of nonpoint-source pollution and applies it to the regulation of agricultural drainage water. Four types of regulatory policies are considered. The empirical analysis is carried out for cotton production in the San Joaquin Valley of California. Variable inputs are the quantity of water applied and the type of irrigation system. All four policies can achieve economic efficiency under the conditions assumed here, but the policies differ in terms of the distributional impacts and administrative requirements.     

ESTIMATING THE WATER QUALITY BENEFITS FROM SOIL EROSION CONTROL1

ABSTRACT: A framework for estimating the water quality benefits from soil erosion was developed. The framework is based on the linkages between soil erosion and offsite damages. The linkages are: erosion on the field, movement of eroded materials to waterways, impact of discharged material on water quality parameters, impact of water quality changes on ability of water to provide economic services, and the economic value of the changes in water use. These linkages need to be modeled in order to estimate the water quality benefits from reductions in soil erosion. Methods for modeling each link on a geographic level, which enables the analyses of national soil conservation, were examined. Areas where data or models were found to be lacking include transport of sediment and nutrients to water systems, impact of discharged materials on water quality parameters, and impact of water quality on ability of water to provide economic services. An economic evaluation of 1983 soil conservation programs was presented as an example of how the framework could be used. A number of simplifying assumptions were made to represent links that could not be modeled with available data.     

环境电磁污染和防治

本文对环境电磁污染的现状,危害及产生作了部份介绍;同时阐述了污染的防治技术和目前该项工作尚存在问题。     

城市环境水文问题分析

城市化对水环境污染是一个具有普遍性和严重性的问题.城市水环境污染分为点污染和面污染两类.本文针对城市降雨径流污染(城市面源污染)作了系统分析.其内容包括城市化对降雨径流的影响,城市面污染的积累和暴雨径流的冲刷,以及推求城市暴雨径流污染负荷过程的模拟途径.     

Comparative analysis of air pollution emissions by electric utilities: Public policy implications

One of the objectives of US environmental regulations was to reduce industrial air pollution emissions, especially from the electric utility industry, the major industrial air polluter. In this study, a comparative analysis of air pollution emissions from fossil-fuel-burning electric utility plants is conducted. The analysis focuses on a 12-yr period from 1975 to 1987 for three air pollutants: particulates, surfur dioxide, and nitrogen oxides. The results indicate that particulate emissions have been significantly reduced but that sulfur dioxide and nitrogen oxides are still major problems for a number of plants. Furthermore, the disparity in the performance by plants indicates that by using current technology, the industry as a whole could greatly reduce these emissions. These results have policy implication for future environmental legislation.