刈割利用对封育沙地土壤水分的影响

在腾格里沙漠南缘长期封育沙地区，通过一个生长季的定位观测，分析研究全刈割和刈割一半两种利用强度对封育沙地土壤水分生态的影响，结果表明：在天然植被围栏封育区和人工种植+围栏封育区，全刈割、半刈割处理下的土壤含水量与对照间均存在显著差异。植被对土壤水分的消耗量随着刈割利用强度的增加而减小，封育沙地0～80cm各层的土壤含水量总体上具有随刈割利用强度的增加而增大的变化趋势；在3-7月份沙地土壤水分逐步降低的过程中，全刈割处理、半刈割处理与对照间土壤水分含量的差异较大，而在7-9月份沙地土壤水分逐步回升的过程中，不同利用处理间土壤水分含量的差异则显著减小；不同利用强度下封育沙地土壤水分随深度增加均表现为先增加后降低的变化趋势，在0～30cm土壤层，离地表越近，土壤含水量越低，而在30～70cm土壤层，则表现为随深度增加而快速下降的趋势。不同强度的刈割处理与对照间各深度层的土壤含水量差异大多都表现为：全刈割处理﹥半刈割处理﹥不刈割处理。表明刈割利用对封育沙地土壤水分生态具有一定的调节改善作用。

The Effect of the Cutting Using on Soil Water of Fencing Sandy Land

Based on located observation of a growing season, the effects of different cutting utilization (all cutting and half cutting) on soil moisture of fencing sandy land in the southern margin of the Tenggeli Desert were studied. The results showed that in enclosed natural vegetation and artificial+closed fencing planting plots, there were significant differences in soil moisture between all cutting and half cutting with the ck. The exhaustion of soil moisture for vegetation decreased and the soil moisture of different layers within 100 cm increased with the increase of cutting intensities. As the soil moisture decreased gradually from March to July, there were great differences in soil moisture between all cutting and half cutting with the ck. However, the soil moisture increased gradually from July to September, the difference of the soil moisture was reduced in different cutting using treatments. The soil moisture in desert-closing protection of different using intensities increased at first, and then decreased with the increase of soil depth. In 0-30 cm, the nearer the earth's surface, the lower the soil moisture was. However, in 30-70cm, it decreased quickly with the increase of soil depth. The difference of the soil moisture between different cutting using intensities and the ck was in the following order: some regulation and improvement effects on soil moisture of fencing sandy land.