Influence of vegetation parameters on runoff and sediment characteristics in patterned Artemisia capillaris plots

• 来源期刊: 干旱区科学(英文版)
• 学科: 农学
• 关键词: arid and semi-arid areas Artemisia capillaris patches runoff and sediment roots and shoots vegetation parameters
• 年，卷（期）: 2014,（3）
• 页码范围: 352-360
• 页数: 9页
• 分类号: S157
• 语种: 中文

摘要

Vegetation patterns are important in the regulation of earth surface hydrological processes in arid and semi-arid areas. Laboratory-simulated rainfall experiments were used at the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Yangling, northwestern China, to quantify the effects of Artemisia capillaris patterns on runoff and soil loss. The quantitative relationships between runoff/sediment yield and vegeta- tion parameters were also thoroughly analyzed using the path analysis method for identifying the reduction mechanism of vegetation on soil erosion. A simulated rainfall intensity of 90 mm/h was applied on a control plot without vegetation(C0) and on the other three different vegetation distribution patterns: a checkerboard pattern(CP), a banded pattern perpendicular to the slope direction(BP), and a single long strip parallel to the slope direction(LP). Each patterned plot received two sets of experiments, i.e. intact plants and roots only, respectively. All treatments had three replicates. The results showed that all the three other different patterns(CP, BP and LP) of A. capillaris could effectively reduce the runoff and sediment yield. Compared with C0, the other three intact plant plots had a 12%–25% less runoff and 58%–92% less sediment. Roots contributed more to sediment reduction(46%–70%), whereas shoots contributed more to runoff reduction(57%–81%). BP and CP exhibited preferable controlling effects on soil erosion compared with LP. Path analysis indicated that root length density and plant number were key pa- rameters influencing runoff rate, while root surface area density and root weight density were central indicators affecting sediment rate. The results indicated that an appropriate increase of sowing density has practical signifi- cance in conserving soil and water.