兰州市郊区土壤水稳定性微团聚体的组成分析

微团聚体是土壤肥力的物质撞础．水稳性的微团聚体质量分数能够反映土壤的肥力状况．通过对兰州市郊区29个样点的分析得出：水稳性微团聚体质量分数少,使得土壤易板结．该现象在调查区已经明显出现;有机质质量分数与土壤的微团聚休质量分数呈正相关,但相关性不显著;碳酸钙质量分数与土壤中的水稳性团聚体呈显著相关．这在粘粒质量分数和有机质质量分数低的钙质土壤中．碳酸钙成为土壤团聚体的重要胶结剂．改善土壤结构必须重视有机肥料的使用;灌溉技术要改进,传统的漫灌方式不仅对土壤结构有很大的破坏作用,而且浪费水资源;用养结合才能保障土壤可持续利用。

Composition of stable micro-aggregates in the soil of Lanzhou suburbs

This study focuses on the composition and stability of micro-aggregates in the suburban soil of Lanzhou.The main findings are as follows:The content of stable micro-aggregates was low,which generally results in hardened soil. This phenomenon had been discovered in the study area. The content of organic matter had no linear correlation with the amount of micro-aggregates. This result may results from the low content of organic matter.The content of CaCO 3 had notable positive correlation with that of the aggregates. So CaCO 3 would become the important cement of soil to form the micro-aggregates in low organic matter and little clay soil. By a comparison with the natural soil,several tentative conclusions can be drawn from this and previous studies:Organic manure can play an important role in the soil structure. Therefore,we should pay attention to the use of organic manure in soil.Traditional ways of irrigation such as flooding that destroys the soil texture should be changed. Modern irrigating methods such as spraying and dripping should be chosen instead.Land use should be combined with protection to make soil development sustainable.