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981.
982.
根据对哈尔滨市所辖8区蔬菜生产基地土壤环境的调查和监测,利用土壤综合污染指数进行评价,哈尔滨市蔬菜生产基地土壤质量状况。 相似文献
983.
本文以2001年至2005年辽河铁岭段及其支流监狈嘲招为依据,分析“十五”期间辽河铁岭段及其支流水质污染状况、污染原因,并提出相应的治理措施。 相似文献
984.
985.
The July 2006 war waged by Israel on Lebanon caused an estimated USD 1 billion of direct (financial) damage to infrastructure. However, it generated also significant indirect (economic/inter-temporal) costs. One sector that suffered considerably in this respect was agriculture, the main source of income for 30–40 per cent of Lebanese. This paper's main objective is to develop a methodology to estimate the total—direct and indirect—cost of the war to agricultural crop production, using an area of south Lebanon as a focal point. The indirect loss assessment viewed inter-temporal reductions in crop production values as the opportunity cost of not working fields due to the presence of unexploded ordnance (UXO). Various crops were evaluated for two scenarios (50 and 100 per cent damage due to UXO) over UXO-clearance periods of five and 10 years. The results indicate that any damage estimates that include only direct losses will under-estimate total losses by 80 and 87 per cent for the five- and 10-year periods, respectively. 相似文献
986.
系统采集秦岭安河铅锌尾矿复垦区尾砂、覆土、蔬菜、作物和中药材等样品,采用火焰原子吸收光谱法测定了样品中Pb、Zn、Cu、Cd 的质量比,并依据国家标准对其进行了评价.旨在调查当地铅锌尾矿复垦作物的重金属污染现状,探讨蔬菜、作物和中药材等重金属污染与覆上、尾砂的关系.提出防控铅锌尾矿复垦作物重金属污染的技术对策.结果表明:1)尾矿复垦与污灌作物中的重金属普遍超标,不能食用,其中污灌地菠菜叶Ph超标1 910倍,葱叶Cd超标1750倍.复垦地玉米籽粒Pb超标35倍,黄豆籽粒Cd超标.189倍;2)尾矿复垦作物中的重金属质量比与尾砂、覆土的重金属质量比具有高度的正相关关系,其污染与铅锌选矿活动有关;3)尾矿复垦地上的小麦、黄豆和玉米籽粒中重金属质量比趋势是:小麦最高,黄豆次之,玉米最低,重金属质量比与作物生长期呈正相关;4)不同植物组织部位中Zn、Cu、Pb、Cd等重金属质量比趋势均表现为:根最高,攀叶次之,耔实最低. 相似文献
987.
从现代安全理论的角度,论述企业安全管理工作的主要内容、重点工作方面安全管理不到位可能发生的事故后果,以期达到保证企业的安全生产的目的。 相似文献
988.
煤矿危险源风险预警与控制的研究 总被引:2,自引:1,他引:1
根据现代安全管理的理论与方法,结合煤矿人-机-环境特点和不同煤矿事故的发生机理,对煤矿危险源风险预警和控制的基本理论和方法进行了探讨,提出了基于危险源的煤矿风险预警与控制的一般流程,给出煤矿危险源辨识、风险评价、监控和预警的方法,为煤矿安全管理信息系统提供理论基础。 相似文献
989.
Spatial variability of organochlorine pesticides (DDTs and HCHs) in surface soils from the alluvial region of Beijing, China 总被引:1,自引:0,他引:1
ZHANG Hong-yan GAO Ru-tai HUANG Yuan-fang JIA Xiao-hong JIANG Shu-ren 《环境科学学报(英文版)》2007,19(2):194-199
The spatial variability in the concentrations of 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis-(p-chlorophenyl) ethane (DDT) in surface soils was studied on the basis of the analysis of 131 soil samples collected from the surface layer (0-20 cm depth) of the alluvial region of Beijing, China. The concentrations of total HCHs (including α-, β-, γ-, and δ-isomers) and total DDTs (i ncluding p,p'-DDT, p,p'-DDD, p,p'-DDE, and o,p'-DDT) in the surface soils tested were in the range from nondetectable to 31.72 μg/kg dry soil, with a mean value of 0.91, and from nondetectable to 5910.83 μg/kg dry soil, with a mean value of 32.13,respectively. It was observed that concentrations of HCHs in all soil samples and concentrations of DDTs in 112 soil samples were much lower than the first grade (50 μg/kg) permitted in "Environment quality standard for soils in China (GB15618-1995)". This suggests that the pollution due to organochlorine pesticides was generally not significant in the farmland soils in the Beijing alluvial region. In this study, the spatial distribution and trend of HCHs and DDTs were analyzed using Geostatistical Analyst and GS (513).Spatial distribution indicated how these pesticides had been applied in the past. Trend analysis showed that the concentrations of HCHs,DDTs, and their related metabolites followed an obvious distribution trend in the surface soils from the alluvial region of Beijing. 相似文献
990.
Denitrification potential enhancement by addition of external carbon sources in a pre-denitrification process 总被引:3,自引:0,他引:3
The aim of this study is to investigate the denitrification potential enhancement by addition of external carbon sources and to estimate the denitrification potential for the predenitrification system using nitrate utilization rate (NUR) batch tests. It is shown that the denitrification potential can be substantially increased with the addition of three external carbon sources, i.e. methanol, ethanol, and acetate, and the denitrification rates of ethanol, acetate, and methanol reached up to 9.6, 12, and 3.2 mgN/(g VSS.h), respectively, while that of starch wastewater was only 0.74 mgN/(g VSS,h). By comparison, ethanol was found to be the best external carbon source. NUR batch tests with starch wastewater and waste ethanol were carried out. The denitfification potential increased from 5.6 to 16.5 mg NO3-N/L owing to waste ethanol addition. By means of NUR tests, the wastewater characteristics and kinetic parameters can be estimated, which are used to determine the denitrification potential of wastewater, to calculate the denitrification potential of the plant and to predict the nitrate effluent quality, as well as provide information for developing carbon dosage control strategy. 相似文献