苍梧县崩岗洪积扇农田土壤理化特性

崩岗是中国南方最严重的土壤侵蚀类型之一，给土地资源带来了相当大的威胁，尤其是崩岗产生的洪积物严重影响到洪积扇农田的土壤性质。分别选择苍梧县龙圩镇崩岗洪积扇果园和稻田为研究对象，探讨洪积扇土壤理化特性。结果表明：崩岗侵蚀导致洪积扇农田土壤退化，土壤性质均显著弱于对照区，同时由扇顶到扇缘，土壤容重呈现减小的趋势，孔隙度和饱和含水量呈增加的趋势，土壤砾石和砂粒含量均逐渐减少，粉粒和粘粒含量则逐渐增加，养分也随之呈增加趋势。Pearson相关分析显示，土壤容重、砾石、砂粒与土壤养分指标呈负相关关系，土壤孔隙度、饱和含水量、粉粒、粘粒与土壤养分指标呈正相关关系。

Soil Properties of Alluvial Fan Soil of Collapsing Gully in Cangwu County

Collapsing gully is one of the soil types most seriously eroded in southern China, and considerablly threats land resources, affects the nature of the farmland soil especially in the alluvial material generated by collapsing gully. In this paper, we chose Cangwu Longxu alluvial fan collapsing gully orchards and rice fields as the research object, studied alluvial fan soil physical and chemical properties. The results showed that: Collapsing erosion led to alluvial fan farmland soil degradation, soil properties were significantly weaker than the control area, while from the start to to fan edge, soil bulk density, gravel and sand content showed a decreasing trend, porosity, saturation water content, silt and clay content showed an increasing trend, nutrients was also in an increasing trend. Pearson correlation analysis showed that soil bulk density, gravel, sand and soil nutrient indicators showed a negative correlation between soil porosity, saturated water content, silt, clay and soil nutrient indicators showed a positive correlation.