紫色土坡耕地磷素径流流失特征分析

Phosphorus Loss from Runoff at Slope Plots of Purple Soil Area

以径流小区定位监测为基础,研究了紫色土坡耕地在不同处理下坡耕地磷养分流失现状,研究磷养分流失与施肥量的关系,不同耕作方式对磷流失量的影响.研究结果表明:①磷素流失与降雨量、径流量呈现出一定的相关性,即同一时期内,降雨越多,产流越多,养分流失就越多;②不同的施肥水平下,总磷流失率随着施肥量的增加而增加,增量处理是优化处理时1.53倍.而可溶性磷的迁移与施肥条件没有明显的相关关系;③不同的耕作方式下,顺坡耕作的总磷流失率为横坡垄作的5.34倍;④玉米不同生育期,土壤总磷随地表径流迁移的强度其大小顺序各个处理表现为:抽雄开花期,拔节期,成熟期.

Basing on the location monitoring runoff plots,the studies of the purple soil in different treatments of farmland under the status of phosphorus nutrient loss,nutrient loss study of phosphorus and the relationship between fertilization and different farming methods on the impact of loss of phosphorus,which measured the loss of the P factor were done.The results show that： ① nutrient loss and rainfall runoff showed a certain degree of relevance,that is,during the same period,the more rainfall,more phosphorus nutrient loss;② the loss rate of TP（Total Phosphorus） was increasing with the application rates of fertilizer.There was no difference between the loss rate of DP（Dissolved phosphorus） and the application rates of fertilizer;③ with different farming measures,the loss rate of TP under longitudinal ridge was 1.53 times of the one under cross ridge;④ during various bearing stages of summer maize,there were obvious differences in the losses of phosphorus by runoff,with the order of jointing stage〉tasseling stage〉maturing stage.