干湿两季等高绿篱红壤浅沟坡面土壤水分空间变化

以红壤丘岗区等高绿篱浅沟坡面为研究对象,比较干湿两季有无绿篱浅沟坡面土壤水分的空间分布,并对试验小区的径流量以及土壤侵蚀量进行对比.结果表明:在旱季,小区土壤含水率变化随着土层加深均呈现增长的趋势；在雨季,无绿篱小区土壤含水率随着土层加深呈现增长的趋势,而绿篱小区土壤含水率表现为30 cm土层＞45 cm土层＞15 cm土层；绿篱小区的土壤水分变异系数随着土层加深呈降低趋势,相同土层干湿两季绿篱小区土壤水分变异系数均大于无绿篱小区土壤水分变异系数.在干湿两季,坡中位置绿篱小区土壤含水率始终大于无绿篱小区土壤含水率,坡上和坡下位置上绿篱小区土壤含水率小于无绿篱小区土壤含水率,种植等高绿篱的坡面保水保土效果明显,使植物在干湿两季能充分利用浅沟坡面水分,对缓解季节性干旱、保持水土起到显著作用.

Spatial variation of soil water in red soil slope-land with ephemeral gullies under contour hedgerow in wet and dry seasons

Ephemeral gully plays an important role in soil losses in hilly red soil region.A field experiment was carried out to study the impact of contour hedgerow on spatial variation of soil water in red soil slope-land with ephemeral gullies.The results showed that there was an upward trend for the soil moisture from the soil surface to the bottom in the dry season.However,there was an upward trend for the soil moisture from the soil surface to the bottom in plot in the rainy season without contour hedgerow setting while it shows that the trend was 30 cm soil layer>45 cm soil layer>15 cm soil layer in the plot with contour hedgerow setting.The coefficient of variation of soil moisture in plot with contour hedgerow setting showed a decreasing tendency from the soil surface to the bottom,and it is larger than that of plot without contour hedgerow setting in the same layer.In the wet and dry seasons,the soil moisture in plot with contour hedgerow setting is more than that of plot without contour hedgerow setting at slope middle,but less at upper slop and lower slop.Therefore,the contour hedgerow can maintain soil and water effectively,making the plants to take advantage of shallow slope water in the wet and dry seasons,which plays a significant role in easing seasonal drought and conserving soil and water.