摘要
【目的】研究不同植被格局对坡面产流产沙特征的影响,为黄土高原水资源匮乏地区坡面水土保持植被格局的优化配置提供依据。【方法】采用野外模拟降雨试验,测定5种植被格局(2种块状镶嵌格局、横条带状格局、顺坡带状格局和裸地格局)的产流产沙特征及土壤入渗特征,探讨坡面不同植被格局和破碎度对产流、产沙、入渗的影响。【结果】(1)植被具有良好的蓄水减沙效益,植被的减沙效益为47.44%~91.67%,蓄水效益为25.67%~62.94%,植被的减沙能力强于蓄水能力。(2)植被格局对坡面的产流产沙量均有显著性影响(P<0.05),试验所设置的几种格局的蓄水减沙效益依次为:块状镶嵌格局>横条带状格局>顺坡带状格局。块状镶嵌格局水土保持效果最佳。(3)不同植被格局的产流过程均呈现“快速上升-相对稳定”的趋势,植被格局有助于延迟坡面径流峰值的出现时间。(4)植被斑块的破碎化指数与侵蚀产沙呈反比,植被斑块破碎化程度越高,侵蚀产沙量越低,蓄水减沙效益越好。(5)不同植被格局的入渗系数为:块状镶嵌格局>横条带状格局>顺坡带状格局>裸地,Horton模型对不同植被格局土壤入渗的拟合效果较好。【结论】通过以上研究发现,块状镶嵌格局的蓄水减沙效益明显优于裸地和顺坡带状格局,因此在水资源有限的黄土区,可以采取植被与裸地交替分布的方式种植植被,以达到蓄水、减沙效益最大化。
[Objective]In order to provide the basis for the optimal allocation of vegetation patterns for soil and water conservation in the Loess Plateau and other water resource deficient areas,the effects of different vegetation patterns and fragmentation on runoff and sediment yield were studied.[Method]To explore the impacts of different vegetation patterns on runoff,sediment,and infiltration in this research,we measured the characteristics of runoff,sediment,and soil infiltration of five vegetation patterns(block-shaped mosaic pattern plots SP1,SP2,horizontal strip pattern plot BP,slope band pattern plot LP,and bare land pattern plot CK,respectively)by field simulated rainfall tests.[Result](1)In general,vegetation had relatively good capacity in sediment reduction and water storage.The sediment reduction efficiency reached 47.44%-91.67%,and the water storage efficiency reached 25.67%-62.94%.Therefore,the sediment reduction capacity of vegetation was stronger than the water storage capacity.(2)The vegetation patterns had statistically significant effects on the runoff and sediment yield on the slope(P<0.05).The order of the highest to lowest storage and sediment reduction effects of vegetation patterns were block-shaped mosaic pattern,horizontal strip pattern,followed by the slope band pattern.Thus,the block-shaped mosaic pattern had the best soil and water conservation effect.(3)The process for the runoff occurrence of different vegetation patterns showed a trend of“a rapid-rise phase followed by a relative stable phase”.The vegetation patterns helped to delay the occurrence of the runoff peaks.(4)The fragmentation index of vegetation patches was inversely proportional to the erosion and sediment production.The higher the degree of fragmentation of vegetation patches was,the lower the sediment yield and the better the efficiency of water storage and sediment reduction were.(5)The infiltration coefficient of different vegetation patterns was in the following order:the block-shaped mosaic pattern>horizontal strip p
作者
王恒星
张建军
孙若修
张佳楠
Wang Hengxing;Zhang Jianjun;Sun Ruoxiu;Zhang Jianan(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;National Field Research Station of Forest Ecosystem in Jixian County,Jixian 042200,Shanxi,China)
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2021年第3期85-95,共11页
Journal of Beijing Forestry University
基金
国家重点研发计划项目(2016YFC0501704)。
关键词
黄土高原
植被格局
破碎度
产流产沙特征
入渗特征
the Loess Plateau
vegetation pattern
fragmentation index
runoff and sediment production characteristics
infiltration characteristics
