几种草被植物的水土保持效应研究

利用小型观测场,对比了几种草被植物地降水、径流量、土壤侵蚀量和土壤的物理性质.结果表明, 与裸地相比,草被植物可以增加土壤的覆盖度,减少降水的径流系数,减少土壤侵蚀量,其中百脉根Lotus corniculatus的效应最为明显.草被植物可以减小土壤容重,增加土壤空隙率,使土壤蓄水保水能力增加,同时提高土壤入渗速率和土壤的抗蚀性,其中百脉根地土壤含水量和入渗速率最大,苇状羊茅Festuca arundinacea地崩解所需时间最长.如苇状羊茅地、葛藤Pueraria lobata地、百脉根地和空旷地0～2 m土层土壤平均含水量分别是15.74%,15.83%,16.06%和14.61%,苇状羊茅、葛藤、百脉根地土壤完全崩解所需时间分别比空旷地多780,627,704 min.

The effect of several grassy species on soil and water conservation

The rainfall-runoff coefficients,soil erosion quantity and soil physical characters were studied in experimental fields in 2002.The results were as follows:grassy lands can increase canopy,decrease runoff coefficient and soil erosion compared with the contrast,the effect of water and soil conservation of pueraria lands is the best than other treatments.At the same time grassy lands can decrease soil bulk density,can lead to better soil water content and come to be better resister of collapse of water and wind.For example,the soil water was 15.74%,15.83%,16.06% and 14.61% in tall fescue lands,in crowfoot lands,in pueraria lands and in uncovered fields,respectively;among these treatments,water content and leaking rate of pueraria lands were the highest,time of resisting collapse of water and wind is the longest in tall fescue lands.