退牧对安西荒漠化草原植被的生态效应

通过对安西温性荒漠化草原退牧还草围栏建设工程区生态环境监测点放牧与退牧管理后草地生物量的跟踪调查和牧草光合生理生态特征的监测,分析显示:与放牧区相比较,围栏退牧草场内的植株生长高度比围栏外放牧区高4.3～4.8 cm,植被覆盖度高16.6%～17.4%,草场平均产草量高235.2～300.5 kg/hm2,植被生长状况良好,同时草原环境中气温较低,湿度较高,且光合速率较高,有利于牧草的生长,表明退牧措施效果显著.高光谱遥感进一步监测结果显示退牧区牧草光谱反射率高,植被盖度大.草原围栏退牧封育,极大地改善了安西县草原生态环境,草原植被得到有效恢复,提高了草原防风固沙、净化空气、保护生物多样性等生态功能.

Ecology effect of retrieving grassland from grazing on desertification grassland vegetation in Anxi

Comparison of biomass and photosynthetic characteristics between grazing and non-grazing meadow was conducted at eco-environmental monitoring site of fencing construction area in temperate desertification grassland in Anxi.The results showed that plant height,vegetation coverage and average forage yield in fenced area were 4.3~4.8 cm,16.6%~17.4% and 235.2~300.5 kg/hm2 higher than that of unfenced area,respectively;indicating an effective improvement measure and a good plant growth condition in terms of lower temperature,higher humidity and photosynthetic rate.The further result from high spectrum remote sensing showed that spectrum reflectance and vegetation covering were higher in fenced area.The fencing improved grassland eco-environment and rehabilitate grassland vegetation effectively,increased its ecological functions of blocking wind,stabilizing sand,cleaning air and protecting biodiversity.