三江平原稻田磷输出及迁移过程研究  

Export of Phosphorus from Paddy Field and Its Transport Process in Sanjiang Plain

作　　者：祝惠[1,2] 阎百兴[1] 

机构地区：[1]中国科学院湿地生态与环境重点实验室,中国科学院东北地理与农业生态研究所,吉林长春130012 [2]中国科学院研究生院,北京100049

出　　处：《湿地科学》2010年第3期266-272,共7页Wetland Science

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-YW-Q06-03);国家自然科学基金项目(40901128,40771035)资助

摘　　要：为了认知三江平原稻田磷的输出机制,通过不同尺度田间原位实验,研究了稻田磷在侧渗输出过程中的含量、侧渗速率以及田埂截留率的变化规律,量化输出磷负荷量;并进一步通过采样分析,揭示磷在各级排水系统中的迁移过程。结果表明,近沟渠田埂对侧渗液中总磷(TP)和可溶性总磷(DTP)的截留率都较高,平均达到50%～60%左右,且随田埂宽度增加,截留能力增强。现有耕作模式下,TP和DTP的年输出总量分别为0.19t/(km2.a)和0.02t/(km2.a),分别占当年施肥总量的9.85%和1.12%。稻田水排出后,其磷含量在水渠—排干—沼泽性河流—江河系统中逐级递减,说明各级排水系统不但起到疏通河道的作用,还具有较好的磷净化功能。As the largest concentrative distribution area for freshwater marshes in China,Sanjiang Plain is of great ecological value for its function of regulating climate,preserving water sources,and protecting biodiversity,etc.Meanwhile,it is one of the main grain-producing areas in China which supplies a significant amount of grain.In order to increase the grain production,paddy field became a major land use type in Sanjiang Plain in recent years,which may lead to adverse effects for water and wetland system because of the nonpoint source pollutants export.Thus,researches on the mechanism of nonpoint source pollution in paddy field are urgent and important for protecting the wetland system and preventing water quality degradation.This study aimed to discuss the export mechanism of phosphorus from paddy field in Sanjiang Plain.Different scales of in-situ experiments were performed to study the concentrations of phosphorus,the intercepting ratio of bund to phosphorus,the lateral seepage velocity during the export process,and to quantify the annual export load of phosphorus.Furthermore,the transport process of phosphorus in drainage systems was also discussed.The artificial drainage,surface runoff and lateral seepage through bund are the three ways of phosphorus export.In the study,the water quantity of artificial drainage and surface runoff was estimated by the summation of each drainage process or runoff event,and the water quality was calculated by the weighted average concentration of phosphorus;the quantity of lateral seepage was calculated by the change of water level,the rainfall and evaporation date according to water-balance of a trench near the paddy field,the quality of lateral seepage water was determined by the weighted average of phosphorus in seepage water sampled from different soil depths.The 102 water samples were sampled from the trench-drain-marshy river-river system before and after the two artificial drainage（in May and August）events so as to test the natural purification ability of the system.The

关 键 词：侧渗 负荷 非点源污染 磷 稻田 三江平原 

分 类 号：X522[环境科学与工程—环境工程]