甘肃省黄土区小流域土壤养分评价

Evaluation of Soil Nutrients in Small Watershed in Loess Area of Gansu Province

在位于黄土高原甘肃省东南部桥子沟小流域内进行调查并采集土壤样品,分不同土壤类型和土地利用类型分层采集土样,选择土壤有机质、速效磷、速效钾、有效铜、有效铁、有效锰、有效锌7项土壤化学指标作为土壤养分的评价指标,建立物元模型评价小流域土壤养分等级,结果显示流域内有机质整体处于极贫乏的水平等级,其他土壤养分指标都处于丰富~适量水平;不同土壤类型中,黄绵土的土壤养分整体水平较灰漠土和黑褐土高;不同土地利用条件下,林地的土壤养分水平最优。

This research was carried out in Qiaozigou small watershed, the southeast of Gansu Province, Loess Plateau.Soil samples of different soil types and land use types were investigated and collected hierarchically. Soil organic matter, available phosphorus, available potassium, available copper, available iron, available manganese and available zinc were chosen as the evaluation indices of soil nutrients. The regional soil nutrient evaluation model was constructed with matter-element model. The results showed the grade of soil organic matter was very lack, and the grades of the other soil nutrient indices rich or moderate in Qiaozigou small watershed. The grades of soil nutrients were higher in Loess soil than in gray desert soil and black-cinnamon soil. Woodland had the best grades of soil nutrients among the different land use types.