文献类型： 外文期刊

作者： Wang, Shuang ¹ ; Feng, Xiaojie ¹ ; Wang, Yongdong ¹ ; Zheng, Zicheng ¹ ; Li, Tingxuan ¹ ; He, Shuqin ² ; Zhang, Xizhou ¹ ;

作者机构： 1.Sichuan Agr Univ, Coll Resources Sci, 211 Huimin Rd, Chengdu 611130, Sichuan, Peoples R China

2.Sichuan Agr Univ, Coll Forestry, 211 Huimin Rd, Chengdu 611130, Sichuan, Peoples R China

3.Sichuan Acad Agr Sci, Soil & Fertilizer Res Inst, 2 Lion Mt Rd, Chengdu 610066, Sichuan, Peoples R China

关键词： Nitrogen loss; Surface runoff; Interflow; Sediment yield; Slope gradient; Maize growth stages

期刊名称：CATENA （ 影响因子：5.198； 五年影响因子：5.594 ）

ISSN： 0341-8162

年卷期： 2019 年 182 卷

页码：

收录情况： SCI

摘要： Nitrogen (N) loss from agricultural nonpoint source pollution results in eutrophication. In this study, the characteristics of N loss were explored using simulated rainfall conditions during different maize growth stages (seedling, elongation, tasseling, and maturity) under different slope gradients (10 degrees, 15 degrees, and 20 degrees), from May to August 2016. The surface runoff and sediment yield increased with increasing rainfall duration. As the slope gradient increased, surface runoff and sediment yield also increased, and N loss accelerated during the maize seedling stage. Interflow and N loss decreased as the slope gradient increased, and the maximum interflow and N loss were found during the tasseling and elongation stages of maize. Similarly, maximum average N losses were recorded during the maize seedling stage for both surface runoff and sediment yield (35.01 mg m(-2) and 5.63 mg m(-2), respectively), while the maximum interflow (163.91 mg m(-2)) was recorded during the elongation stage. The surface runoff and interflow accounted for 9.27%-45.90% and 50.79%-89.35%, respectively, of the average total nitrogen (TN) loss under different slope gradients and during different maize growth stages. Thus, we concluded that interflow was the main pathway for N loss. Surface runoff and interflow mainly contained dissolved total nitrogen (DTN), while nitrate nitrogen (NO3-N) was the primary form of DTN during the different maize growth stages. Path coefficients and contribution rates of slope gradients were the highest for DTN loss in surface runoff and for ammonium nitrogen (NH4-N) loss in interflow. The path coefficients and contribution rates of surface runoff, interflow, and sediment yield were the highest for TN, NO3-N, NH4-N, TN, DTN, NO3-N, and TN loss, respectively. We concluded that surface runoff, interflow, and sediment yield were the main factors affecting N loss at our study site in the purple soil region of southwest China, followed by slope gradient and vegetation coverage.