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Water stress, water transfer and social equity in Northern China--implications for policy reforms 总被引:4,自引:0,他引:4
Cai X 《Journal of environmental management》2008,87(1):14-25
Water stress in Northern China is characterized with major, inefficient irrigation water use and rapidly growing non-agricultural water demands, as well as limited water quantity and declining water quality. Water use in the region is undergoing transfer from agricultural to municipal and industrial sectors. Currently, part of the economic loss and environmental damage due to water stress can be considered as a consequence of water transfer failures, including the current transfers, which hurt farmers' livelihood and income, and the needed transfers, which industry and cities have been waiting for but have not received. This paper starts with a discussion of the causes of water stress in Northern China, which is fundamental to understand the necessity and complexity of agricultural water transfers. Following that, it reviews water transfers in Northern China as a cause for concern over the social stability, economy and environment of the region. Based on an integrated analysis of economic, environmental, fiscal and social implications, this paper begins by identifying critical barriers to smooth water redistribution; and ends with implications for policy reforms, ensuring that farmers can and will save water. It is concluded that the decisions of water reallocation under water stress should be shared by communities at all levels, from the local to the national, to ensure equal access of water, especially the availability of the basic water need for all groups. 相似文献
804.
PCDD/F and dioxin-like PCB in Hong Kong air in relation to their regional transport in the Pearl River Delta region 总被引:3,自引:0,他引:3
PCDD/F and dioxin-like PCB were measured in 142 air samples of Hong Kong. The annual average PCDD/F and dioxin-like PCB concentrations obtained for Hong Kong air at Tap Mun (PCDD/F: 1724+/-1984; dioxin-like PCB: 1572+/-1170 fg m(-3)), Yuen Long (PCDD/F: 2927+/-2695; dioxin-like PCB: 4331+/-1962 fg m(-3)) and Tsuen Wan (PCDD/F: 1875+/-1502; dioxin-like PCB: 2972+/-1510 fg m(-3)) from January 2004 to March 2005 were comparable to other urban centers around the world and were within the Japanese and USA ambient air quality guidelines. A clear seasonal pattern was observed for PCDD/F, generally with a 50-60 times higher air concentration in winter when background northerly wind was weaker and land-sea breeze prevailed, resulting in regional transport; and a lower concentration in summer, due to the inflow of clean oceanic southeasterly wind from the South China Sea. A higher WHO-TEQ value of dioxin-like PCB (mainly attributed to the relatively higher WHO-TEQ value of PCB 126) in Yuen Long during winter, compared with other months, could also be related to the regional transport by the winter monsoon wind and the low mixing height in winter. Spatially, air concentrations of PCDD/F and dioxin-like PCB demonstrated a west-to-east gradient (with Yuen Long>Tsuen Wan>Tap Mun). It is suggested that PCDD/F and dioxin-like PCB were transported into the western airshed of Hong Kong from the Pearl River Delta by land-sea breeze circulation and confined to the northwestern part, due to the blocking effect of the northwestern airshed in Hong Kong. 相似文献
805.
化工装置工业管道面临焊接和腐蚀两大问题,装置的长期运行与管道定期检验的矛盾日益突出。通过对数字射线、脉冲涡流、超声导波三种管道在线检测技术的对比分析,结合基于风险的检验(RBI)理念,探索出一套适用于工业管道在线检验的技术,对节约企业成本、保障管道安全具有重要意义。 相似文献
806.
采用显示性比较优势理论,对2005-2010年我国华北地区5个省市人均CO2净排放和单位GDP CO2净排放的显示性比较优势做了分析;同时采用变异系数差异分析,结合空间自相关分析方法,对其空间格局和演变规律做了深入研究.研究发现,华北地区5省市人均CO2净排放高于全国平均水平.北京、天津、河北、山西4个省市出现下滑势头,而内蒙古自治区呈现大幅上升势头.山西单位GDP CO2净排放在全国最高,天津和北京低于全国平均水平.华北地区人均CO2净排放和单位GDP CO2净排放比较优势空间分别呈现负相关和正相关特性. 相似文献
807.
贵州万山汞矿区汞的环境污染及对生态系统的影响 总被引:34,自引:9,他引:34
通过对贵州万山汞矿地区环境样品(水、土壤、植物、农作物和动物)的系统研究,发现该地区的环境汞污染以土壤、大气污染为主,水体基本处于正常范围.土壤汞含量为24.31~347.52mg·kg-1,比全国土壤平均值高出2~3个数量级;水中汞含量除了冶炼厂荷花池中含量较高外,其它水体为0.10~0.68ng·mL-1.由于矿山长期的开采和冶炼,整个环境的汞污染严重,当地的植被、农作物、动物中存在明显的汞蓄积,各种植物不同部位的汞含量为0.47~331.4mg·kg-1;苔藓可以高度富集汞. 相似文献
808.
火电厂烟气排放连续监测系统(Colltinuous emissions monitoring systems)以下简称CEMS)是为环境执法机构提供数据,对企业的排污状况进行跟踪和管理的一个重要手段,环保技术部门参比方法(国家或行业发布的标准方法)是作为检验GEMS准确度的重要方法。2008年江苏省装机容量300MW以上火电厂GEMS比对监测的过程中,部分电厂CEMS与参比监测方法数据存在一定的差异,本文对此进行分析并找出原因,用参比的手工监测方法进行校验、指导CEMS,以此提高CEMS监测数据的代表性、准确性和可比性,让CEMS更好的服务于环境管理。 相似文献
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810.
Antibiotic micro-pollution is usually found at the ng/L–level in drinking water sources or discharge water of wastewater treatment plants. In this study, a novel approach mediated by manganese oxidizing bacteria (MnOB) in a biofilter was developed to control the pollution. The results indicated that the biogenic manganese oxide (MnOx) produced during the oxidation of the feeding manganese ions could coat the surface of the filtering sand effecting the simultaneous removal of antibiotics. It was found that the removal of antibiotics is insured as long as the feeding manganese was well removed and was not influenced by the hydraulic loading. The growth rate of the MnOB group revealed that the antibiotic concentration at 50 and 100 ng/L promoted their activity, but it was inhibited at 500 and 1000 ng/L. The structure of the bacterial community was stable in the presence of antibiotics (50 ng/L), but their extracellular processes changed. The removal performance of the feeding manganese seemed to relate to the extracellular processes of the dominant bacterial genus. Moreover, the freshly formed MnOx was a buserite-like material that was rich in Mn(III) and Mn(IV) (94.1%), favoring the degradation. The biofilter did not generate additional antibiotic resistant genes in the presence of antibiotics. 相似文献