关键词: 生物量, 草畜平衡, 若尔盖地区, 枯草指数

Abstract: Under the dual pressure of natural withering and continuous grazing by livestock,the above ground biomass of winter and spring grasses continues to be decreased,making this period become a high incidence and recurrence period of ecological damage and livestock disasters. Therefore,this study utilized Landsat satellite imagery from the Ruoergai region and established an optimal estimation model for winter grass biomass based on the Dead grass vegetation index (DGVI). The validation R² of the model reached 0.791 1. Based on this,a spatio-temporal dynamic monitoring and evaluation method for the forage-livestock balance in winter was proposed,and the grassland stock and overload status in different months of winter in the Ruoergai area were calculated. The overloading rate in this area rapidly increases from November to January in the early winter period and in most areas. It reaches an overloaded state and remains basically stable from January to February of the following year. The dynamic estimation method of winter forage-livestock balance based on DGVI has higher accuracy and stronger application ability than the estimation of winter forage-livestock balance using green vegetation index. The research results provide a feasible application technology and new ideas for the spatio-temporal dynamic monitoring and evaluation of winter forage-livestock balance during the dry season.

Key words: Biomass, Forage-livestock balance, Ruoergai region, Dead grass vegetation index