陕北多沙粗沙区乡村聚落土壤侵蚀的典型流域调查与估算——以碾庄沟流域为例

Investigation and Estimation of Soil Erosion of Rural Settlements in Abundant and Coarse Sediment Area of North Shaanxi——An Example in Nianzhuanggou River Basin

随着乡村聚落的发展,陕北多沙粗沙区乡村聚落土壤侵蚀的严重性已经凸显。以碾庄沟流域为例,研究了乡村聚落土壤侵蚀方式,并对侵蚀总量进行了估算。结果显示:从乡村聚落土壤侵蚀的主要方式来看,以新建窑洞的弃土侵蚀最大,窑洞坍塌侵蚀次之,聚落水蚀侵蚀量最小,其中塌窑侵蚀和建窑侵蚀两项合计占到乡村聚落土壤侵蚀总量的94.6%;从乡村聚落的侵蚀总量来看,面积占1.08%的乡村聚落产生的侵蚀量却占到全流域侵蚀总量的6.83%,人居侵蚀模数达6.3万t/(km2.a)或8.18 t/(人.a)。因此,对乡村聚落土壤侵蚀应加以重视,而土壤侵蚀的防治工作应该以新建窑洞的管理和废弃窑洞坍塌的治理为重点。

With development of the rural settlement, soil erosion becomes more and more serious in Abundant and Coarse Sediment Area of North Shaanxi. Taking Nianzhuanggou reaches as an example, the soil erosion patterns are studied and amount of soil erosion is evaluated in this paper. The results indicate that in view of main soil erosion patterns in rural settlements, the amount of soil erosion due to construction of new caves is the greatest, erosion amount due to cave collapse takes second place and the amount of water erosion is the least. The former two are the main soil erosion patterns, accounting for 94. 6% of the total amount of rural settlement erosion. In view of the total erosion amount of rural settlements, the amount of soil erosion resulted by the rural settlements which possesses only 1.08% of the area of the whole Nianzhuanggou river basin accounts for 6. 83% of the total erosion of the whole area. The living environment erosion modulus reaches 63 thousand tons per square kilometer per year or 8. 18 tons per year per person. Therefore, attention must be paid to the soil erosion in rural settlements. The efforts for soil erosion prevention should be focused on the management of cave construction and proper treatment of abandoned and collapsed caves.