玉米季横垄坡面径流及可溶性有机碳流失特征

发布时间：2018-03-09 05:08

本文选题：玉米　切入点：生育期　出处：《中国水土保持科学》2017年05期 　论文类型：期刊论文

【摘要】：为了探明紫色土坡耕地玉米各生育期可溶性有机碳流失特征与迁移途径,为玉米种植过程中有机碳流失有效防控提供科学依据。通过采用野外径流小区和人工模拟降雨相结合的方法,探讨紫色土玉米季坡耕地地表径流、壤中流及其可溶性有机碳的流失特征。结果表明,地表径流量受降雨再分配作用明显,表现为苗期最大,抽雄期最小;壤中流则受降雨强度和降雨再分配作用的影响较小。地表径流DOC质量浓度均呈现逐渐降低的趋势,且2.0 mm/min降雨强度下DOC质量浓度初值相对较高;而壤中流DOC质量浓度呈现先升后降的趋势,在1.0 mm/min降雨强度下变化最为显著。自产流开始30 min内,地表径流DOC迁移负荷表现为苗期成熟期拔节期抽雄期,且受降雨强度影响较大;而壤中流DOC迁移负荷表现为苗期拔节期抽雄期成熟期,且受降雨强度影响不明显。同一生育期,壤中流DOC质量浓度高于地表径流,且壤中流产生晚于地表径流,但壤中流DOC迁移负荷却是地表径流DOC迁移负荷的1.35倍。玉米生育期对地表径流量影响明显,壤中流是紫色土坡耕地DOC迁移的主要方式,径流DOC质量浓度的变化取决于产流时间和生育期的变化。
[Abstract]:In order to find out the characteristics of soluble organic carbon loss and the migration pathway of maize in different growth stages in sloping soil of purple soil. This paper provides a scientific basis for the effective control of organic carbon loss during maize planting. By using the method of combining field runoff plot with artificial simulated rainfall, the surface runoff of maize season sloping farmland in purple soil is discussed. The characteristics of soil runoff and its loss of soluble organic carbon. The results showed that the surface runoff was significantly redistributed by rainfall, which was the largest in seedling stage and the smallest in pumping stage. Surface runoff DOC concentration decreased gradually, and the initial value of DOC concentration was relatively high under 2.0 mm/min rainfall intensity. However, the DOC concentration in the soil flow increased first and then decreased, and the change was most significant under the rainfall intensity of 1.0 mm/min. Within 30 min from the beginning of the self-producing flow, the surface runoff DOC transport load was shown as the jointing stage in the seedling maturity stage, and the topping stage at the jointing stage. The transport load of DOC in the middle flow of soil was at the stage of jointing stage and mature stage, and was not affected by the rainfall intensity. The DOC concentration in the middle stream of soil was higher than that of the surface runoff in the same growth period, and the transport load of DOC in the middle stream of soil was higher than that of the surface runoff. The DOC transport load of soil flow was 1.35 times as much as that of surface runoff DOC transport load. Maize growth period had a significant effect on surface runoff, and soil intermediate flow was the main mode of DOC migration in purple soil sloping farmland. The variation of DOC concentration in runoff depends on the runoff time and growth period.
【作者单位】：四川农业大学林学院;四川省水土保持与荒漠化防治重点实验室;四川农业大学资源学院;
【基金】：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) 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)
【分类号】：S157

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