免耕制度下耕作土壤结构演化的数字图像分析

利用数字图像方法 ,研究了室内模拟和自然田间免耕下的土壤结构演化状况。图像定性表明随免耕时间的推移土壤中团聚体由小变大 ,土体逐渐趋于紧实。图像定量分析结果表明随着免耕时间的推移 ,小团聚体和小孔隙减少而大团聚体和大孔隙增加。田间土样的结果表明了自然的阶段性降雨对土壤结构可能具有一定的调节作用 ,但从图像与团聚体粒径分布和孔隙孔径分布的变化来看 ,免耕是否有利于土壤性质和农业生产尚很难确定

IMAGE ANALYSIS OF DEVELOPMENT OF CULTIVATED SOIL STRUCTURES UNDER NON-TILLAGE SYSTEM

This paper, by using digital image method, studied the structural development of cultivated soils under non-tillage system with simulated laboratory conditions and natural filed conditions. The obtained images qualitatively showed that aggregates in soils became larger, and soil blocks became more compacted under the states of non-tillage. The analytical results of aggregate and pore size distributions clearly showed that smaller aggregates and pores decreased while larger aggregates and pores increased. The results of field soil samples also showed that natural interval rainfall may have a function on adjustment of soil structure, yet it is still uncertain whether non-tillage system is beneficial to soil properties and agricultural production if judged from the soil images and the changes of aggregate and pore size distributions.