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291.
近年来,环境监测能力建设项目资金投入不断加大,项目规模增长迅速,实施任务日益繁重,项目绩效考核要求越来越高,但项目管理还处于比较粗放的状态。在分析环境监测能力建设项目管理现状和需求的基础上,提出通过转变项目管理模式、强化信息支撑手段、完善制度建设、培养管理人才等多种手段,提高项目管理的科学性和时效性,实现重点项目管理的精细化、科学化和规范化。 相似文献
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Ma YG Cheng JP Jiao F Duo KX Rong Z Li M Wang WH 《Environmental monitoring and assessment》2008,146(1-3):127-138
Distribution and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in drinking water resources have been carried out for the first time in Henan Province, China. Water samples collected from four river systems and their tributaries, as well as groundwater resources, were analyzed according to EPA method 525.2. Total of 68 water samples were collected in 18 cities in Henan province in May, August and November, 2001. Concentrations of sum of 16 priority PAHs in water samples ranged from 15 to 844 ng/L with a mean value of 178 +/- 210 ng/L (n = 68). The spatial and temporal distribution of PAHs showed that the Huanghe and the Huaihe river systems had relatively higher concentrations of total PAHs. Higher concentrations of total PAHs were observed in August and November than in May, with respective mean values of 262, 232 and 33.6 ng/L. Ratios of Ant/(Ant + Phe) and Flur/(Flur + Pyr) were calculated to evaluate the possible sources of PAH contamination, which indicated that the coal combustion sources were the main contributors to PAHs in most drinking water resources. Some petrogenic (or pyrolytic) sources of PAHs were also found. The toxic equivalency factors (TEFs) were used to calculate benzo[a]pyrene equivalents (BaPE) for water samples. The average value of BaPE was 0.6 ng/L. The values in most stations were much lower than the guideline values in drinking water of Chinese Environmental Protection Agency (CEPA, 2.8 ng/L) and the US Environmental Protection Agency (US EPA, 200 ng/L). Overall, the drinking water resources in Henan province showed some carcinogenic potential. 相似文献
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Xiyong Hou Mingjie Li Meng Gao Liangju Yu Xiaoli Bi 《Environmental monitoring and assessment》2013,185(1):267-277
Annual normalized difference vegetation index (NDVI) and chlorophyll-a (Chl-a) concentration are the most important large-scale indicators of terrestrial and oceanic ecosystem net primary productivity. In this paper, the Sea-viewing Wide Field-of-view Sensor level 3 standard mapped image annual products from 1998 to 2009 are used to study the spatial–temporal characters of terrestrial NDVI and oceanic Chl-a concentration on two sides of the coastline of China by using the methods of mean value (M), coefficient of variation (CV), the slope of unary linear regression model (Slope), and the Hurst index (H). In detail, we researched and analyzed the spatial–temporal dynamics, the longitudinal zonality and latitudinal zonality, the direction, intensity, and persistency of historical changes. The results showed that: (1) spatial patterns of M and CV between NDVI and Chl-a concentration from 1998 to 2009 were very different. The dynamic variation of terrestrial NDVI was much mild, while the variation of oceanic Chl-a concentration was relatively much larger; (2) distinct longitudinal zonality was found for Chl-a concentration and NDVI due to their hypersensitivity to the distance to shoreline, and strong latitudinal zonality existed for Chl-a concentration while terrestrial NDVI had a very weak latitudinal zonality; (3) overall, the NDVI showed a slight decreasing trend while the Chl-a concentration showed a significant increasing trend in the past 12 years, and both of them exhibit strong self-similarity and long-range dependence which indicates opposite future trends between land and ocean. 相似文献
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Hongxia Gao Yidian Dong Chunyan Meng Weijun Guan Yingli Liu Guizhi Xing 《Environmental monitoring and assessment》2013,185(3):2475-2482
This work aimed to determine the DNA and oxidative damage on mice by mixtures of organic contaminants in wastewater-irrigated soil, in order to assess their usefulness as markers for this kind of pollution. Wastewater-irrigated soil samples in the vicinity of an industrial area in Tangshan, China were collected, and soil irrigated by underground water satisfying drinking water standards was used as control group. Organic pollutants were extracted from the soil using ultrasonic oscillation, and analyzed by gas chromatography–mass spectrometry (GC-MS). Meanwhile, DNA damage on mice was determined by the Comet assay after oral gavage with the extracts, and changes in total superoxide dismutase (T-SOD) activity, glutathione peroxidase glutathione, GSH peroxidase (GSH-PX) activity and malondialdehyde content in serum of mice were investigated. The number of categories and concentrations of organic compounds in the wastewater-irrigated soil is more than those in groundwater-irrigated soil, as identified by the GC-MS. The toxicity test of mice showed that compared with reagent control group, the activities of T-SOD and GSH-PX decreased; the tailing rate of peripheral blood lymphocyte of mice increased and was more than that of the control group. This shows that mammalian toxicity end points can be used to determine the joint toxicity of organic pollutants in soil. When there is no means to identify each and every pollutant in soil, it is feasible to evaluate the combined effects of various pollutants to determine the extent to which the soil is polluted. 相似文献
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大气环境综合观测研究站(简称大气超级站)是开展大气环境污染综合立体观测、进行大气重污染过程污染特征动态表征、深入分析大气污染成因的重要平台。了解中国当前不同地区大气超级站的建设和应用现状、存在的问题及发展需求,有利于科学指导和规范中国大气超级站的设计、建设、运维和应用,提高其在大气重污染过程应急管控和空气质量改善中的技术支撑能力。研究通过对国内60余个大气超级站进行问卷调研,综述了中国目前大气超级站的现状,并基于统计分析结果,对中国大气超级站发展提出建议。 相似文献