人工降雨条件下不同粒径泥沙中氮磷流失特征分析  

Loss Characteristics of Nitrogen and Phosphorus in the Sediment of Different Sizes under Artificial Rainfall

作　　者：李波[1] 李晔[1] 韩惟怡[1] 秦华[1] 赵建博[1] 

机构地区：[1]武汉理工大学资源与环境工程学院,武汉430070

出　　处：《水土保持学报》2016年第3期39-43,共5页Journal of Soil and Water Conservation

基　　金：国家水体污染控制与治理科技重大专项(2012ZX07104-002)

摘　　要：针对香溪河流域农业面源污染严重以及坡耕地传统耕作模式造成的氮磷流失等问题,选取库区典型石灰性土壤进行人工模拟降雨试验,研究地表径流和不同粒径泥沙中氮磷等养分流失特征。结果表明：地表径流中不同形态氮素养分的流失过程,均表现为降雨初期出现浓度峰值,之后随降雨的进行迅速降低,TP输出浓度先有一个较小幅度的下降过程,之后随产流时间的延长而增加,最后趋于稳定;流失泥沙颗粒组成表现为粘粒（〈2μm）与细砂粒（20-200μm）含量随降雨过程进行有一定增加,而粉粒（2-20μm）和石砾（〉2000μm）含量却有所降低,粗砂粒（200-2 000μm）含量则几乎不变;不同粒径径流泥沙中各养分流失浓度最大的均为粒径〈2μm粘粒,粒径〈200μm的颗粒各养分流失贡献率均高达70%以上,表明水土流失导致土壤中大量细小颗粒与养分流失,其中流失泥沙携带的养分含量与细小颗粒含量呈明显的正相关。For serious agricultural nonpoint source pollution, and nitrogen and phosphorus in Xiangxi River Watershed Sloping loss caused by traditional farming patterns and other issues, selecting reservoir typical calcareous soil carried out artificial rainfall simulation experiment to study characteristics of nutrient loss about different particle surface runoff and sediment nitrogen and phosphorus and so on. The results showed that： the loss in runoff process different forms of nitrogen nutrients expressed as peak concentration of rainfall occurs early, after decreased rapidly with rainfall conduct. TP output decreased concentration process prior to a smaller amplitude after time with runoff prolonged increase, and finally stabilized. The loss of sediment particles showed 〈2μm clay and fine sand content 20-200μm process with a certain increase in rainfall, while 2-20μm particles and 〉2 000μm gravel content reduced, 200-2 000 μm coarse sand content was almost unchanged. Different sizes of each nutrient runoff and sediment loss of concentration were the largest particle size 〈2 μm clay, particle size 〈200 μm particle contribution of each nutrient loss rate as high as 70%, indicated soil erosion resulting in a large number of fine particles of soil and nutrient loss, including the loss of sediment carried by the nutrient content and the content of fine particles were positively correlated.

关 键 词：人工降雨 石灰土 粒径 氮磷流失 

分 类 号：S157.1[农业科学—土壤学]