水蚀风蚀交错区六道沟流域土壤肥力评价

Evaluation of Soil Fertility in Liudaogou Watershed Located in a Water-Wind Erosion Area

本研究在六道沟流域采集土壤样品74个,通过测试分析各指标值,建立评价指标体系,采用模糊综合评价法(Fuzzy)与层次分析法(AHP)相结合的手段,计算出土壤肥力综合性指标值(IFI),对六道沟流域土壤肥力进行评价.结果表明:从土地利用类型来看,农用地IFI最高(0.68),表明农用地土壤肥力较好,荒草地和林地次之(IFI分别为0.53和0.40),灌木地土壤肥力最差(IFI为0.35).空间分布格局上,IFI以六道沟流域主沟线为中心向周围递减.总体来看,六道沟流域土壤肥力质量处于中下等水平,其中第3级土壤所占面积最大,占流域总面积的46.9%.处于1和2级的土壤仅占到流域面积的23.8%,而处于3-5级的土壤占到76.2%,是前者的3倍多.

Seventy-four soil samples were collected in Liudaogou watershed located in a water-wind erosion area in Shaanxi. An evaluation system for soil fertility was established by determining the related indexes of the samples. An integrated soil ation （Fuzzy） used in combination watershed. Of the 4 types of land fertility index （IFI） was calculated based on fuzzy comprehensive evalu- with analytic hierarchy process （AHP）, to evaluate soil fertility of the use investigated, farmland had the highest IFI （0. 68）, followed in sequence by grassland （0.53）, woodland （0.40） and shrubland （0. 35）. Based on its spatial distribution pat- tern, IFI of Liudaogou watershed was found to diminish steadily from the main trench line outward to the adjacent locations. Overall, the quality of soil fertility in Liudaogou watershed is at a medium-low level,which can be classified into five grade levels. The third grade covers the largest area, accounting for 46.9% of the total. The first and second grades only account for 23.8% of the total, while the third,fourth and fifth grades account for 76.2% of the total.