北方地区植物篱系统土壤水分特征曲线模拟与分析

Simulation and analysis of soil water retention curves within and between hedgerows in Northern China farm systems

以北方风沙区、黄土区、黑土区的典型植物篱为研究对象,在测定植物篱系统带内、带间部位土壤质地、土壤孔隙度、有机质含量、水稳性团聚体等指标的基础上,采用Van Genuchten模型模拟了不同地区植物篱土壤水分特征曲线。结果表明,风沙区、黑土区植物篱带内土壤孔隙度、有机质、水稳性团聚体含量均比带间高,黄土区植物篱带内土壤孔隙度、有机质、水稳性团聚体含量则比带间的低;各区域植物篱系统带内土壤含水率均比带间高,并且土壤持水力(土壤含水率)随着土壤水吸力的增大而减弱,风沙区植物篱带内、带间土壤持水力最弱,黑土区植物篱相应部位土壤持水力最高。说明植物篱具有改善土壤质地、结构,提高土壤含水率的作用,在治理坡面水土流失方面具有重要意义。

This study aimed to simulate soil water retention curves within and between hedgerows of farm systems in northern China by the Van Genuchten model.Typical hedgerow systems in regions of sandy,loess and black soils were selected for study.The soil texture,soil porosity,soil organic matter and soil water-stable aggregates within and between hedgerows were measured.It was found that the soil porosity,soil organic matter and soil water-stable aggregates within hedgerows in sandy and black soil areas were higher than those from between hedgerows;but this result was adverse in loess area.The soil moisture content within hedgerows was higher than that between hedgerows.The soil water holding capacities within and between hedgerows were lowest in sandy soils and highest in black soils.It was concluded that hedgerows can improve soil texture,structure and soil water retention,and make an important contribution to control of sheet erosion on sloping land.