呼伦贝尔草原区返青期的遥感监测研究

摘要

In this paper, based on the data of MODIS -NDVI vegetable index from 2000 to 2014 , we monitored the returning green period and the vegetation growth of Hulun Buir Grass-land by using the double Logistic ( D-L) as the function fitting methods of NDVI time-series. We also analyzed the effect of the "Grassland ecological protection and compensation mecha-nism"in Hulun Buir Grassland. The results showed that Hulun Buir Grassland returning green period is most concentrated in April. And after the implementation of the "grassland ecological protection and compensation mechanism", the return green area in April increased proportion by 13%, showing that the general trend of the returning green period was advanced. The vegetable returning green period is mainly affected by the regional hydrothermal conditions. Extreme cli-mate phenomena is an important reason to affect the returning green period to be significantly de-layed or clearly advanced. After the implementation of the policy, the steppe returning green pe-riod and vegetation growth states showed overall trend become better. The research results can provide important scientific basis for the implementation of seasonal grazing and forage livestock balance system in the steppe area.%以2000-2014年MODIS植被指数NDVI数据为基础,使用双Logistic函数作为NDVI时间序列的滤波函数,对呼伦贝尔草原返青期的时间与植被长势进行动态监测,同时分析"草原生态保护补助奖励机制"在呼伦贝尔草原区的实施效果. 研究结果表明,呼伦贝尔草原返青期以4月份最为集中,实施"草原生态保护补助奖励机制"后,4月份返青的面积占比提高了13 %,表现出返青日期总体提前的趋势. 植被返青时间主要受区域水热条件的影响,极端气候现象是导致返青期显著推迟或明显提前的重要原因.政策实施后,草原返青期植被生长状况表现出总体向好的态势. 研究成果可为在草原区实行季节性放牧和草畜平衡制度提供重要的科学依据.