摘要
土壤风蚀造成的直接生态后果是土地资源的退化。在春播前两次沙尘暴事件中,对科尔沁沙地几种具有代表性的土地类型的土壤风蚀量及土壤特性进行了野外测定、分析,结果表明:(1)在同一沙尘暴天气下,由于土地利用和耕作方式的不同,土壤风蚀量存在着差异,新垦农地和翻耕农地的风蚀量显著高于未垦草地、免耕农地和麻黄地;免耕农地则与未垦草地的风蚀量相差不大,风蚀危害较轻;麻黄地几乎不受风蚀侵害。新垦农地、翻耕农地、免耕农地、未垦草地、麻黄地两次观测的土壤风蚀量平均值依次为24.59、15.60、2.26、1.46和0.22 g/h.cm2。(2)基于土壤特性计算的土壤退化指数结果表明,新垦农地和翻耕农地发生了较为严重的退化。
Soil erosion results in degradation of the land resources and destroys the ecological environment. This paper investigated the soil erosive volumes and analyzed the soil properties of several typical lands in Horqin Sandy Land with two sand storm events before Spring Seeding, aiming at appraising the changes of soil ero sive volumes and quantitatively describing the extent of soil degradation accord ing to soil degradation index, under the different means of land use and cultivation in the studied areas. The conclusions are: (1) there are differentia in soil erosive volumes under the same sandstorm weather due to the different means of the land use and cultivation. Of the five land types, new -reclaimed farmland,cu ltivated land,no -till farmland in -cult grassland and Ephedra land, the amount of soil erosion are evidently higher in the new - reclaimed farmland and the cultivated land than that of other types because of the different means of land use and cultivation; There is little discrepancy in erosive volumes between no - till f armland and in - cult grassland where the erosion are not serious ; Ephedra land is hardly suffered from erosion. The average values of soil erosive volumes of the two sandstorms are 24.59,15.60,2.26,1.46, 0.22 g · h^-1. cm^-2 cor responding to the five land types. Additionally, different wind velocity in a sandstorm may ca use different erosive intensity, the faster the wind blow, the more sand moved b y airflow. (2) According to the comparison of the particle size distribution among the different land types, it can be seen that the volumes of middie and fine s and in new - reclaimed farmland and cultivated land are obviously higher than that of other land types, while the volumes of extreme fine sand and silt are lower. In in - cult grassland,no - till farmland and Ephedra land the volumes of extreme fine sand and silt improved evidently result in the protection of ground litter and pen ed the serious degradation in new- reclaimed farmland and cultivated land.
出处
《干旱区地理》
CSCD
北大核心
2006年第6期861-866,共6页
Arid Land Geography
基金
国家社会科学基金资助项目(05BJY024)
中国科学院寒区旱区环境与工程研究所知识创新工程项目(210097)
关键词
土地利用与耕作
输沙量
土壤特性
土壤退化指数
科尔沁沙地
land use and cultivation
windblown sediment
soil properties
soil degradation index
Horqin Sandy Land