艾比湖流域典型植物生长的水文地质条件研究

在野外实际调查资料基础上,总结了艾比湖流域典型植物胡杨、梭梭、红柳赋存的地貌位置、当前主要存在问题、适生地下水位埋深、包气带岩性与结构等水文地质条件,为流域的综合治理提供依据。     

核电厂人因及组织行政管理安全审查体系

定期安全审查 (PSR)是国际原子能机构 (IAEA)近年推广的一种新的核电厂安全审查方式 ,它强调系统性、全面性和关键性。人因安全因素 (HF)、组织机构和行政管理安全因素 (OA)是PSR的重要组成部分 ,也是PSR中审查难度较大的部分之一。其难点主要在于如何用有限的评审指标去刻画出最能表征人因、OA对核电厂安全运行最具影响的特征因子 ,建立起科学的、系统化的审查体系 ,且该体系还需具有较强的可操作性。基于上述认识 ,笔者建立了核电厂人因及组织行政管理安全审查体系 ,它包含安全目标与方针、人员配备与资格、组织机构与管理、配置控制、培训、职业健康、运行经验反馈、质量保证、人 -机接口、遵章守法等 10类 19个要素。同时介绍了其评审指标、审查内容、审查方法和程序等。该体系已应用于秦山核电厂。     

Uptake and Metabolism of TNT and GTN by Plants Expressing Bacterial Pentaerythritol Tetranitrate Reductase

The manufacture and improper disposal of explosives has resulted in a significant amount of land requiring remediation. The compound 2,4,6-trinitrotoluene (TNT) is the most persistent and toxic of the explosive pollutants with current treatment methods being energy intensive and costly. Bacterial enzymes such as pentaerythritol tetranitrate reductase (PETNR) from Enterobacter cloacae PB2 have been found to have activity against TNT; however, microbes often lack the biomassnecessary for remediation applications. The PETNRgene (onr1) was transformed into tobacco plants in an attempt to combine the metabolic diversity of microbes with the sequestering properties of plants. The resulting transgenic plants were shown to have enhanced tolerance to TNT during germination and as seedlings. Phytoremediation applications with these plants may provide an alternative treatment of TNT contamination.     

WATER SUPPLY DILEMMAS OF GEOTHERMAL DEVELOPMENT IN THE IMPERIAL VALLEY OF CALIFORNIA1

Abstract: There are four known geothermal resource areas in the Imperial Valley that have a combined potential of over 4,000 megawatts of electrical energy for 25 years. Water resources available to support geothermal enerfy development are imprted Colorado River water, agricultural waste waters, Salton Sea water, and groundwater. In addtion, geothermal power plants can produce their own cooling water from steam condensate. Nevertheless, the relatively high water requirements of geothermal facilities along with a series of real and potential constraints may cause water supply dilemmas involving both the acquistion and use of cooling water. Important constraints are institutional policies, water supply costs, technical problems, and impacts upon the Salton Sea. These constranits and related dilemmas are examined in light of relevanty information on the valley's water resources, geothermal resources and energy technologies, cooling water requrements, and water supply options.     

A Hydrological Model for Predicting the Effects of Dams on the Shoreline Vegetation of Lakes and Reservoirs

/ The species richness of shoreline vegetation of unregulated lakes in Nova Scotia, Canada, is known to increase as a function of catchment area, a topographic variable governing water level fluctuations. Predictions based on catchment area however, fail to account for richness patterns at the margins of lakes enlarged by dams. Here, we compare the vegetation and hydrological regimes of regulated and unregulated systems. Hydrological regimes of regulated systems deviated from natural systems of similar catchment area by being either hypovariable or hypervariable for both within-year and among-year fluctuations in water level. Plant communities of dammed systems were less diverse, contained more exotic species, and were, with one exception, devoid of rare shoreline herbs. Data from "recovering," or previously dammed systems indicated that shoreline communities can be restored upon return of the appropriate hydrological regime. Using observed within-year and among-year water level fluctuation data, we propose a general model for the maintenance or restoration of diverse herbaceous wetlands on shorelines of temperate lakes or reservoirs. Managers can manipulate the within-year water level variation within prescribed limits (1-2 m), while ensuring that among-year variation (SD of summer levels) is less than 25% of within-year variation. This preliminary model is based on data from low-fertility, temperate lakes in river systems. To calibrate the model, plant community data from other regions are needed, as are long-term water-level data for unregulated lakes, data which are essential but largely lacking in many areas.KEY WORDS: Catchment area; Regulated lakes; Shoreline restoration; Rare plants; Exotic plants; Diversity     

植物整治技术在重金属废水处理中的应用

综述了植物整治技术的一般原理和研究现状 ,介绍了藻类植物、草本植物、木本植物在重金属废水治理中的应用。     

应用生化单元深度处理电镀废水

一般认为电镀废水中缺乏充足的有机污染物 ,因而少有将生化单元应用于电镀废水处理。分析电镀废水中依然可能存在充足的溶解性有机物 ,通过在一电镀废水治理工程中利用生化进行深度处理的实际应用 ,结果表明该单元的存在不仅必要 ,而且可行 ,实际运行所排放的废水水质指标远低于排放标准。     

微电解法处理电镀废水

通过对酸性含Cr6+、Ni2+、Cu2+的电镀废水进行"微电解—中和—混凝沉淀"处理的实验,发现只要满足微电解接触时间大于5min,中和后pH>7.5这两个条件,处理后的废水中重金属浓度即可达标,并根据这一结果,开发出"微电解含Cr6+—中和—混凝沉淀"的电镀废水处理新工艺,实践证明其运行简便,处理成本低,效果好。     

种养殖耦合的海水农业系统研究

本研究建立了养殖耦合的海水农业系统,结果表明,种养殖耦合的海水农业系统对污染物具有良好的净化效果,对Chl.去除效果尤其显著,污染物NO3-N、NO2-N、NH4-N、TP、COD、TN、Chl.的去除率分别为:58.11、58.61、62.86、54.45、52.62、46.84和85.69%.用养殖废水种植蔬菜,实现了废水无害化和资源化的统一,具有较好的经济、生态效益.     

Pollution of NPEOs in four municipal sewage treatment plants in the north of China

The concentration and distribution of nonylphenol polyethoxylates (NPEOs represents the mixture, and NPnEO represents the monomer) and its metabolites in the influent and effluent of four municipal sewage treatment plants (STPs) in the north of China were measured. Moreover, the concentration and distribution of the above chemicals in the sludge of two STPs were also determined, and the transfer and fate of NPEOs in the sewage treatment process were discussed primarily by analyzing the distribution of the products in the effluent and the sludge. The results showed that NPEOs and its metabolites existed in all the samples of the influent, effluent, and sludge. NPEOs were degraded in the sewage treatment process with the removal efficiency in the range of 23.38%–77.11%, or an average of 52.86%. However, the large analogs of NPnEO were only degraded to small ones, whose degradation rate was rather slow, and consequently the degradation was not complete. Hence, the concentrations of some small metabolites, such as nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), and nonylphenol diethoxylate (NP2EO) were elevated in the effluent. These small metabolites are more toxic than the large NPnEO analogs, and some of them were reported to exhibit environmental endocrine disrupting activity. From this point of view, the process of sewage treatment does not reduce but elevate the risk of NPEOs, which becomes the main source of these small NPnEO in the environment. The sludge exhibited good adsorption ability for NPEOs, especially for the small analogs, which led to the high level of NPEOs in the sludge. Hence, reasonable disposal of the surplus sludge to avoid re-pollution is very important. Translated from Research of Environmental Sciences, 2006, 19(3): 61–66 [译自: 环境科学研究]