摘要
20世纪70年代以来,中国重要的湖泊和河流水域如五大湖泊、三峡库区、滇池、白洋淀、南四湖、异龙湖等氮、磷富营养化问题急剧恶化。研究结果表明,在中国水体污染严重的流域,农田、农村畜禽养殖和城乡结合部的生活排污是造成水体氮、磷富营养化的主要原因,其贡献率大大超过来自城市生活污水的点源污染和工业的点源污染。20世纪80年代初以来,在各重要流域菜果花(蔬菜、水果、花卉)播种面积增加了4.4倍。菜果花种植为新型产业,农民并未掌握合理的施肥技术。由于种植效益高,菜农为了追求效益,超高量使用氮、磷肥料,单季作物化肥纯养分用量平均为569～2000 kg·ha-1,为普通大田作物的数倍甚至数十倍,成为水体富营养化的主要潜在威胁之一。与此同时,农村养殖产业带的发展,使得一些地方畜禽养殖产生的氮、磷数量剧增,最大已达到1 721 kgN·ha-1和639 kgP2O5·ha-1,大大超过了农田可承载的安全负荷,成为各大水域的重要污染源。而城乡结合部地带缺少排污管网等基础设施,加上这一地带城区快速扩张,使之成为城区面源污染的主要来源。分析结果还显示,尽管中国农业面源污染的程度已十分严重,然而,各主要驱动因素仍然有增无减,进入21世纪初,中国农业面源污染对水体富营养化的影响将进一步加剧,农业和农村发展引起的水?
Since 1970s, the N and P eutrophication of major Chinese lakes and water systems has been getting worserapidly. Investigation revealed that non-point source pollution from agriculture and rural region is the leading source ofwater pollution. The contribution of non-point source pollutants from fertilization of crop land, rural animal husbandry andliving sewage of transition region between rural and urban area is much greater than that of point-source from wastes of civildomestic and industry in urban area with developed wastewater pipe nets. Since 1980s, the acreage of vegetables, fruits andflowers has been increased by 4.4 times. Due to high profit, it is common using very high rates of N and P fertilizers on thesecrops. The average fertilizer application rate is 569-2000 kg (pure nutrient)ha-1 in single crop, about 10 times as that forgrain crops. The increasing vegetable area with high fertilizer input is one of the biggest potential problems for eutrophicationof water bodies in watersheds. At the same time, animal breeding farmers in rural region intended to be developed in apattern that certain townships with very high concentration of animal breeding farmers. N and P amount from animalhusbandry in such concentrated region has reached very high level, as much as 1721 kg N and 639 kg P2O5 per hectareagricultural land area, far more surpassing the acceptance capacity of soil to these organic nutrients. In almost all of theimportant watersheds in China, non-point source N- and P-discharge to aquatic ecosystem from animal husbandry isbecoming a crucial pollution source. Fast expansion of new city zones without wastewater pipe nets in transition regionbetween rural and urban area makes such zones the main non-point source pollution. The research results also showed thatalthough the non-point source pollution is already serious in the country, the growing influence factors will lead to evenworse situation in the early 21 century. The non-point source pollution from agriculture and rural area will become one of the
出处
《中国农业科学》
CAS
CSCD
北大核心
2004年第7期1008-1017,共10页
Scientia Agricultura Sinica
基金
农业部重点资助项目
国家科技部"973"资助项目(G1999011806
2002CB410800)
国家科技部重大专项资助项目(K99-05-35-02)
上海市农委资助项目[农科功字(2002)第4-1-4号]
关键词
中国
农业面源污染
21世纪初期
形势估计
控制
水体富营养化
Eutrophication
Nitrate pollution in groundwater
Non-point source pollution
Dianchi lake
Taihu lake
