基于SQI的岷江上游干旱河谷肥力空间分异特征

Spatial Differentiation Characteristics of Soil Fertility in the Dry Valley of the Upper Minjiang River Based on Soil Quality Index

选择岷江上游干旱河谷杂谷脑河流域为典型研究区域,通过调查取样、理化分析和模型计算,定量分析该区土壤肥力的空间变异特征。结果表明:土壤有机质、有效磷、全钾和有效钾的含量沿河呈现先升高后略下降的趋势;全氮、有效氮和pH值缓慢增大;全磷呈现上下波动状态。土壤有机质、全氮、有效氮和全钾含量随着海拔升高而增大;全磷、有效磷和有效钾含量随着海拔升高而先增大后降低;pH值略有降低。岷江上游干旱河谷高半山区域(2 000 m以上)土壤保持了较高水平的土壤质量,而杂谷脑河下游土壤质量优于上游。

Understanding the spatial differentiation characteristics of soil fertility in dry valley of the upper Minjiang River plays a key role in man - land relationship and coordinated development of resources and environment. Based on investigation and calculation of chemical properties of soil samples and method of soil quality index to quantitatively analyze the characteristics of soil horizontal and vertical zonality in dry valley of the upper Minjiang River. The results show that： the soil organic matte （SOM） , available phos-phorus （AP） , total potassium （ TK） and available potassium （ AK ） content increased first and decreased afterwards along the river gradient. The total nitrogen, available nitrogen and pH value content increased slowly, and the total phosphorus content presented a fluctuation state. The soil organic matte （SOM） , total nitrogen （TN） , available nitrogen （AN） and total potassium （TK） content increased with the increase of altitude. Total phosphorus （TP） , available phosphorus （AP） and available potassium （AK） increased first and decreased afterwards with the increase of altitude, and the pH value decreased slowly. The results of soil quality index indicated that the soil quality maintained higher in the upper reaches of the Minjiang River, and soil quality in the downstream of the river were better than that in the upper reaches of the river.