长江三角洲地表水环境污染规律及调控对策

根据野外实地考察和定点观测数据 ,结合历年环境监测资料 ,初步揭示了长江三角洲地表水环境污染的现状与近十年来的时空演变规律 :河网干流水质基本良好 ,中小河流污染突出 ;城市河流有机污染严重 ,普遍出现水体黑臭现象 ;湖泊氮磷含量逐年增高 ,水体富营养化加剧 ;市郊小城镇河网水质急剧恶化 ,已成为新的水环境污染中心。造成长江三角洲地表水环境污染的主要物源包括工业废水和生活污水、畜禽粪便、农田化肥、底泥等。针对上述污染规律和成因机制 ,提出了相应的调控对策。

POLLUTION PATTERNS AND MODULATING COUNTERMEASURES OF SURFACE WATER ENVIRONMENTS IN THE YANGTZE DELTA

On the basis of the field investigation and experimental data, the status and spatial and temporal patterns for the last decade in surface water pollution were revealed in the Yangtze delta. The water qualities of large rivers are still very well, but most of medium and small rivers have been polluted very seriously. The rivers in city are mainly polluted by the oxygen demanded organic matters,with water become more black and odoriferous. The concentrations of nitrogen and phosphorus in lakes are increasing annually,accelerating the process of the eutrophication. The surface water quality in small towns become rapidly deteriorating, and each small town is becoming a new water pollution center. The pollutants in surface water of the Yangtze delta are mainly originated from industrial waste, municipal sewage, dejecta of livestocks and poultry, chemical fertilizers in field, bottom sediments in rivers and lakes, and so on. In the light of above pollution patterns and origins, modulating countermeasures have been proposed. The rules and laws on water environment protection and water pollution prevention and control in valleys should be made much more perfect. A uniform and regional agency of water environmental management should be established.A lot of sewage plants should be built quickly in order to increase the sewage treatment ratio and the level of waste water purification.The integrate harness of dejecta of livestock and poultry should be strengthened to make them resourceful,reducible and innocuous.The amount of chemical fertilizer in field should be reduced and the quantity of organic and complex pertilizer should be increased.The integrate reparation of medium and small rivers should be enhanced,as well as riverhead protection.