缓丘坡耕地模拟降雨及土壤通透性研究

利用模拟降雨试验,对发育于红砂岩、千枚岩、第四纪红色粘土母质的赣北丘陵旱作红壤和下蜀黄土母质的宁镇丘陵区旱作黄棕壤,进行了水土流失量、土壤水分特征曲线、室内外土壤通透性等测定,并建立了相应的关系方程。结果表明,耕种黄棕壤较耕种红壤,水土流失更为严重,而且亚表层土壤性质对水土流失有重要影响。在类似的模拟降雨条件下,耕种黄棕壤产生的地表径流1525 l,径流含沙量23.4g/l土壤流失量291.7 t/km²,耕种红壤相应值为621.41,1.6g/l和10.8t/km²。亚表层容重、总孔隙度、有效水含量和透水速度,前者分别为1.4,44%,20%,1.4mm/h,后者分别为1.2,52%,21.7%,25mm/h。根据结果还提出了有关耕地夏季灌溉的建议。

STUDY ON SIMULATED RAINFALL AND SOIL PERMEABILI TY OF FLATTISH HILL SLOPING FARMLAND

A simulated rainfall study on cultivated red earths derived from red sandstone, phyllite, quaternary red clay in the northen Jianxi P-ovince and cultivated yellow brown earths from Xiashu Loess in the southern Jliansu Province, including six runoff experimental plots, was conducted for measuring water and soil losses in flattish hill region. Determination of some soil physical properties influencing soil erosion, such as soil permeability, was carried out.