生态环境的脆弱性对垃圾不适当处置的响应

垃圾的不适当处置,对生态环境的负面影响是多方面的。在上海、北京和石家庄等地研究表明,垃圾的随意处置,已经造成了许多环境污染问题:垃圾的污染成分包括“三氮”、COD、BOD、重金属离子、有机污染物等,这些污染物在包气带砂性土的侧向迁移距离约15 m,而在地下水中则可达到120 m/a,在地表水中影响距离可达200 多m,在粘性土中的垂向迁移一般在3 m以浅;Cd、Hg、As、F、Pb等有毒离子在垃圾处置场附近高梁粒的综合污染指数可达192-238,超过国家食品卫生标准高达650倍,在西瓜和甜瓜中,这些离子超标少的几倍,高的达100多或1300多倍;垃圾中COD、Cl-、NH4+、NO3-、NO2-等对地表水的单项污染指数高的达100多倍,并在静止的地表水呈现指数函数衰减;对地下水的单项污染指数高的可达340多倍,高出地下水三类标准100多倍,综合污染指数少的60,高的达170。

RESPONSE OF ECOLOGICAL ENVIRONMENT VULNERABILITY TO INEFFECTIVE DISPOSAL OF GARBAGE

Ineffective disposal of garbage has been causing many environment problems such as water resource, air, and soil pollution. The results of study for the garbage sites of Shanghai, Beijing and Shijiazhuang showed that pollutants from urban solid wastes are beyond number including COD, Cl- , NH4+ , NO3-, NO2- , Cd2+ , Hg2+ , As2+ , F+ , Pb2+ and so on. The pollutants migrate over a lateral distance of 15 m in sandy soils, they move over 200-m distance in surface water, and diffuse at the speed of 120 m/a in groundwaters. The concentrations of Cd2+ , Hg2+ , As2+, F+ and Pb2+ in broom corn are more than 650 times higher than the national foodstuff health standard, comprehensive pollution indices usually range from 192 to 238 and the concentrations exceed 100 times the standard in water melon and muskmelon, comprehensive pollution indices are from several to 100 or 1300. The concentrations of COD, Cl- , NH4+ , NO3- and NO2- in surface water are more than 100 times those of grade-Ⅲ standard surface water, and comprehensive pollution indices are also more than 100. These pollutant concentrations in groundwaters are over 340 times those of grade-Ⅲ standard groundwaters, and comprehensive pollution indices usually vary from 60 to 170. This paper discussed systematically these issues based on a great deal of results obtained by the authors.