中国水土保持科学2017，Vol.15Issue(5)：31-38,8.DOI:10.16843/j.sswc.2017.05.005
玉米季横垄坡面径流及可溶性有机碳流失特征
Characteristics of runoff and dissolved organic carbon loss in slope farmland with contour ridges during maize growth stages
摘要
Abstract
[Background] The purple soil region is one of the typical areas suffering serious soil erosion in Southwest China.At the same time,the growth periods of the maize coincide with the timing of rainstorms.Serious soil erosion would surely result in the loss of runoff and organic carbon.Our aims are to investigate the characteristics of the loss and the migration of dissolved organic carbon (DOC) during the growth period of maize in the slope farmland of purple soil,providing a scientific basis for the effective prevention and control of organic carbon loss during the maize planting.[Methods] Surface runoff,interflow and its loss characteristics of dissolved organic carbon of the whole growth period of maize were studied by the combination methods of field runoff plots and artificial rainfall simulation in slope farmland of purple soil areas.Contour ridge is designed according to local agricultural customs.A total of 12 rainfall simulation experiments are conducted in two 1 m by 2 m boxes under three rainfall intensities (1.0,1.5,and 2.0 mm/min) on a typical slope gradient of 15°.[Results] The surface runoff was obviously affected by rainfall redistribution,and surface runoff presented the maximum in seedling stage and the minimum in tasseling stage.However,the interflow was less affected by rainfall intensity and rainfall redistribution.Although the DOC mass concentration of surface runoff showed a decreasing trend gradually,and the initial value of the DOC mass concentration was relatively higher under rainfall intensity of 2.0 mm/min.The interflow DOC mass concentration showed a trend of rising first and then decreasing and it was most significant under rainfall intensity of 1.0 mm/min.In the first 30 minutes of the runoff generation,the DOC migration load of surface runoff displayed an order of seedling stage ＞ mature stage ＞ jointing stage ＞ tasseling stage,and it was affected greatly by rainfall intensity.However,the DOC migration load of interflow displayed an order of seedling stage ＞ jointing stage ＞ tasseling stage ＞ mature stage,and the effect of rainfall intensity on the transfer load of the interflow DOC was not obvious.During the same growth period,the mass concentration of interflow DOC was higher than that of the surface runoff,besides,but interflow occurrence was later than that of surface runoff.The interflow DOC migration load was 1.35 times of the surface runoff DOC.[Conclusions] The growth period of maize had an obvious influence on surface runoff.Interflow was the main mode of the DOC migration in slope farmland of purple soil.The variation of mass concentration of DOC depended on the time of runoff generation and the change of maize growth stage.关键词
玉米/生育期/可溶性有机碳/地表径流/壤中流/迁移负荷Key words
maize/growth period/dissolved organic carbon/surface runoff/interflow/migration load分类
农业科技引用本文复制引用
武万华,何淑勤,宫渊波,郑子成..玉米季横垄坡面径流及可溶性有机碳流失特征[J].中国水土保持科学,2017,15(5):31-38,8.基金项目
国家自然科学基金“紫色土坡耕地侵蚀演化特征及其对作物防蚀的响应机制”(41271307) （41271307）
四川省教育厅项目“紫色土区玉米季横垄坡面片蚀过程研究”(15ZB0009) （15ZB0009）
