四川盆地紫色水稻土评价方法研究—以蓬溪县水稻土为例

STUDIES OF THE EVALUATION METHODS OF PURPLE PADDY SOILS IN SICHUAN BASIN

通过田间取样实测和调查统计,用定量的方法对土地进行评价,并开展相应的大比例尺制图。评价时注意土壤的自然属性和经济属性对土地生产力的影响,以土地自然生产力高低作为评价的最终指标。与土地自然生产力有关的评价因子,扣除经济属性后,经逐步回归计算。结果表明,影响紫色水稻土自然生产力的因子有:灌溉保证半、土壤有机质含量、土壤全磷含量、耕层厚度、物理性粘粒含量、生物气候潜力值等。

Quantitative evaluation and mapping in large scale(1:10000)were com-pleted based on B&W air-photos(scale 1:15000)and the statistical datataken in the field in Pengxi county,Sichuan province.Much attentionwas paid in the process of evaluation to soil productivity as influencedby its natural and economic properties.The natural productivity of thesoil was taken as the final index for the evaluation.Furthermore,theevaluation factors related to the natural productivity of the soil,exclu-sive of its economic properties,were selected by progressive regressionwith a computer The results showed that 7 principal factors greatlyaffect the natural productivity of rain-fed tilled purple soil,i.e.organicmatter content,tillage depth,field capacity,slope,available phosphoruscontent and bio-climate potential,while 6 were identified for purple pa-ddy soil:irrigation level,organic matter,total P content,tillage depth,physical clay content and bio-climatic potential.