Effects of woodland spatial distribution on soil erosion in small watershed: A case study in Wuqi County, northern Shaanxi
Yao Wenjun, Zhang Yan, Zhu Qingke
School of Soil and Water Conservation, Key Laboratory of Soil and Water Conservation and Desertification Combating,Ministry of Education, Beijing Forestry University,100083, Beijing,China
We analyzed spatial distribution of woodlands and its impact on soil erosion in small watersheds in this study. Thirty nine small watersheds in Wuqi County on the hilly and gully loess plateau of northern Shaanxi Province were selected following the method of uniform sampling (1%). Woodland area proportion, woodland patch density, shape index of woodlands, woodland coverage, and slope position index were calculated for each watershed and taken as elements to carry out hierarchical cluster analysis for the 39 watersheds. Relationship between woodland distribution and soil erosion was analyzed based on soil loss data obtained from the National Soil Erosion Survey. The 39 watersheds were classified into four categories. Watershed category 1 is characterized by a large proportion of woodlands and woodlands are distributed on the lower slopes. For Category 2, the proportion of woodlands is relatively small and woodlands are distributed on the middle slopes. For Category 3, the proportion of woodland is small and distributed on the upper slopes. For Category 4 the proportion of woodlands is large and distributed on middle slopes. Soil loss was negatively correlated with woodland vegetation coverage (P <0.05) in Category 1 and 4. The multiple linear correlation coefficient describing the integrated effects of the five parameters for woodland spatial distribution characteristics on the soil loss is 0.577 (P <0.05). The results indicate that woodland coverage is a major inhibitive factor to soil erosion. Meanwhile, the proportion of woodland area, woodland patch density and shape index can affect soil erosion in the scale of small watershed. To a certain degree, the woodlands on the upper slopes will reduce soil loss in small watersheds.
姚文俊, 张岩, 朱清科. 小流域林地空间分布对土壤侵蚀的影响——以陕北吴起县为例[J]. 中国水土保持科学, 2015, 13(1): 16-22.
Yao Wenjun, Zhang Yan, Zhu Qingke. Effects of woodland spatial distribution on soil erosion in small watershed: A case study in Wuqi County, northern Shaanxi. SSWCC, 2015, 13(1): 16-22.