中文摘要：

本文就不同开垦年限下旱地、水田、菜园和荒地土壤水稳性团聚体、有机C和各养分的变化规律及其相互关系进行了研究。结果表明，荒地开垦为旱地、水田和菜园后，〉5mm的水稳性团聚体含量迅速下降，但随着利用年限的延长，〉0．25mm的水稳性团聚体总量呈增加趋势。早地和菜园土壤有机C的积累速度高于全N，而水田土壤中全N和有机C含量同时迅速上升。土壤全P含量随开垦年限增加快速升高，但土壤K素淋失严重，随着熟化程度的提高而降低。红壤各粒级水稳性团聚体含量与有机C和全N含量之间均达到了显著相关关系，而与全P和全K间相关性不显著。可见，土壤团聚体稳定性程度保持在何种水平，主要取决于农田有机C库及N的平衡状况。

英文摘要：

The variation of water-stable aggregates, nutrients and their correlation in four land uses （upland, paddy soil, vegetable soil and wasteland soil） under different reclamation years were studied. The results showed that the content of〉5 mm aggregates decreased rapidly after the wasteland soil was cultivated to upland, paddy soil and vegetable soil. With the reclamation years prolonged, the total content of 〉0.25 mm aggregates increased. The accumulation rate of soil organic C was higher than soil N for upland and vegetable soil, but kept stable for paddy soil. The content of soil P increased rapidly with the reclamation years prolonged in red soil. And in this study, soil K run offseriously and the content of soil K decreased with the reclamation years prolonged. Soil organic C and soil N were significantly correlated with the content of water-stable aggregates, but soil P and K were not significant correlated with the content of water-stable aggregates. So the level of stability of water-stable aggregates was mainly depended on the balance of soil organic C and soil N.