Potential of weed species applied to remediation of soils contaminated with heavy metals

To screen out a series of ideal plants that can effectively remedy contaminated soils by heavy metals is the main groundwork of phytoremediation engineering and the first step of its commercial application on a large scale. In this study, accumulation and endurance of 45 weed species in ]6 families from an agricultural site were in situ examined by using the pot-culture field experiment, and the remediation potential of some weed species with high accumulation of heavy metals was assayed. The results showed that Solanum nigrum and Conyza canadensis can not only accumulate high concentration of Cd, but also strongly endure to single Cd and Cd-Pb-Cu-Zn combined pollution. Thus 2 weed species can be regarded as good hyperaccumulators for the remediation of Cd-contaminated soils. Although there were high Cd-accumulation in Artemigia selengensis, Znula britannica and Cephalanoplos setosum, their biomass was adversely affected due to action of heavy metals in the soils. If the problem of low endurance to heavy metals can be solved by a reinforcer, 3 weed species can be perhaps applied commercially.     

Effects of traffic pollution on the genetic structure of Poa annua L. populations

The genetic composition of Poa annua L, populations with a series of traffic pollution was studied by starch electrophoresis. Five enzyme systems were stained. The results showed that: (1) Traffic pollution can dramatically change genotypic frequencies at some loci of P. annua populations. Significant deviations from HardyWeinberg equilibrium were observed on loci Fe - 1 and Me due to the excess of heterozygotes in some populations.(2) The effective number of alleles per locus and the observed and expected heterozygosity were higher in the pollution series than in the clear control site(Botanic Park population), but the increase was not related with the pollution extent. (3) Most genetic variation was found within populations, and only 6.21% was among populations of the polluted series. Slightly higher differentiation( FST = 7.98%) was observed when the control population was included. (4) The calculated gene flow(Nm) is 2.8841 per generation. The mean of genetic identity is 0.9864 and the genetic distance average to 0.0138.     

也给山水放个长假

一年三个长假，时光集中消费，吃皇粮的人们真是有福了，一个一个成了时间的小小富翁，平时想做而未能做成的事，可以在这些长假里去拾掇；平时想会而没有时间去会的亲友，可以在这些长假里去欢聚；平时里觉睡不足的人，也大可在这些长假里放心地扯鼾。更有那喜爱旅游的人士，可以好好利用这些长假出门去游山玩水。     

天津、杭州率先完成环境容量测算工作

全国大气和地表水环境容量测算工作进展顺利,目前已有部分省、直辖市完成了主要工作,天津市、杭州市的容量测算工作已通过国家环保总局的审查。 记者从国家环保总局获悉,全国大气和地表水环境容量测算工作正按照东、中、西部的顺序依次进行,将分别在今年7、8、9月之前完成,现在东部地区绝大多数重点城市已完成大气环境容量测算工作,正按程序送审,山东省重点城市大气环境容量测算技术报告已通过审查 据国家环保总局有关部门负责人介绍,天津市是全国第一个完成大气和地表水环境容量测算工作的省级行政区。环保总局的审查组在对天津市递…     

灾害--环境问题的发言人

回顾历史，最初无论在哪个国家的政治舞台上，环保都是跑龙套的。环保最终能登堂人室，是困为请了灾害这个“新闻发言人”：     

Comparison of Pb and Cd adsorption to the surface coatings and surficial sediments collected in Xianghai Wetland

Surface coatings and surficial sediments were obtained in four natural waters in Xianghai Wetland in China to study the role of surface coatings and surficial sediments in controlling the transporting and cycling of heavy metals in aquatic environments. Pb and Cd adsorption to the surface coatings and surficial sediments were measured under controlled laboratory conditions(mineral salts solution with defined speciation, ionic strength 0.0.5 mol/L, 25℃ and pH 6.0 for surface coatings: and 0.00.5 mol/L CaCl2 solution, 25℃ and pH 6.0 for surficial sediments). The Langmuir adsorption isotherm was applied to estimate equilibrium coefficients of Pb and Cd adsorption to the surface coatings and surficial sediments, and the component analyses of surface coatings and surficial sediments were also carried out.Correlation analyses between the maximum adsorption of Pb and Cd (Гmax) and the components in the surface coatings and surficial sediments suggested that there was a statistically significant trend for Pb and Cd adsorption(Гmax) to the surface coatings to increase with increasing in contents of Fe and Mn oxides in the surface coatings and surficial sediments. And the metal adsorption abilities of surface coatings were much stronger than those of surficial sediments, highlighting that in the same water, i.e. at the same pH and initial metal concentrations, the metals(such as lead and cadmium) in supernatant were feasible to be adsorbed by surface coatings than surficial sediments. The more importance of surface coatings than surficial sediments for adsorbing and cycling of heavy metals in aquatic environments was evidenced.     

环境保护和环境容量产权的合理界定

环境容量是经济增长和环境保护兼顾的结合点．通过环境容量资源产权的双重界定,即用在地方政府层面上的界定和企业层面上的界定来实现经济和环境的协调发展．     

城市环境生态系统主要问题与城市工业可持续发展

本文将可持续发展的新观念与我国的城市工业生产相联系，提出发展生态城市，生态工业是解决我国城市环境问题的根本途径。通过分析城市生态系统主要元素（人口环境、大气环境、地面环境、水环境）的现状及发展趋势，提出，综述了一些有针对性的得力保护措施。     

沿江开发环保篇

世界著名工业区大都在大江大河的入海口，作为工业制造大省的江苏省，也处在中国的第一大河——长江的入海口。伴随着火热的夏天的来临，“沿江开发”——作为江苏迎接世界制造业加速向长江三角洲转移的一项前瞻性举措，正在大规模推进，其八百里岸线，正在成为江苏省经济发展的聚焦点。与此同时，现有的环境容量能否支撑新一轮的全面开发。以重工业为主的开发计划将会对环境造成怎样的影响，决策者们采取了怎样的措施来遏翻进一步的污染……这一系列的问题也再次引起了人们的关注，环境保护成为另一个聚焦点。     

湿地保护是可持续发展的重要课题

通过对湿地多方面重要价值的详尽介绍，揭示了国内外一些湿地生态恶化状况及其原因。文章具体提出了我国加强湿地生态保护工作的一些见解，如，提高对湿地保护的认识，提出积极合理的湿地保护目标；确立科学的湿地保护原则，制定并实施湿地保护规划等。     

生态环境的保护和建设是西部大开发的基础

森林是人类赖以生存的基础资源，良好的生态环境是实现人与自然，生态系统和社会经济系统协调发展的重要纽带，是实现西部大开发的基础条件，是建设小康社会的重要内容，高水平的绿化，良好的生态环境，是国家富强，民族繁荣，社会文明的重要标志之一。