紫色土表层和亚表层微生物数量比较

实验室对四川内江、乐山和云南元谋不同类型紫色土表层和亚表层微生物数量特性的比较分析表明：土壤有机质、氮磷钾全量及其速效量均表现为表层高于亚表层，与紫色土类型和利用方式无关；三大类土壤微生物细菌、放线菌和霉菌数量均表现出表层高于亚表层，表明紫色土表层的有机质和通气性优于亚表层，适宜于这三大类微生物生长；温湿气候条件下的四川盆地和干热气候条件下的云南元谋其紫色土微生物数量的剖面变化具有相同的趋势，唯土壤营养状况在四川盆地紫色土中表现为表层优于亚表层，而在云南元谋紫色土中由于表层土壤的退化作用表现为亚表层优于表层的相反情况。

Contrast Research of Microbe Quantity Between Surface and Subsurface Pruple Soil

After analyzing purple soil sampled from Neijiang,Leshan of Sichuan Provinec and Yuanmou of Yunnan Province,the contrast results of microbe quantity feature between surface and subsurface purple soil were obtained as follows.The content of soil organic matter,total and available nitrogen,phosphorous and potassium of surface was higher than subsurface,not relating to the type of purple soil and soil utilization way.The quantity of microbe_bacteria,actinomyces and mould in surface purple soil was higher than subsurface,which indicated that the organic matter and airy condition in surface soil was more suitable for microbe's growing.There was the same tendency in profile change of microbe quantity in purple soil located in temperate_humid climate of Sichuan basin in contrast with dry_hot climate of Yuanmou,Yunnan.The nutrient situation of purple soil in Sichuan basin shown that state of surface was better than subsurface,while in Yuanmou of Yunnan the state was on the contrary due to the degradation of surface soil.