The factors affecting the estimation of pasture biomass using non-destructive methods in the forest-steppe zone of Mongolia

摘要

Monitoring of pasture biomass is essential to utilize the resources more efficiently and sustainable way.The standard method to determine the biomass is to cut plants growing in the pasture.But labor and time intensive,and it also causes some damage to the pasture.So,there is a need to develop a non-destructive method which is easy and accurate.Therefore,a field type portable Normalized Difference Vegetation Index(hereinafter referred as NDVI)meter was used in nine different pastures(seven in mountainous and two in meadow pastures)to detrmine NDVI two times in a year at 30 spots which represented the vegetation in each pasture.At the same time,the aboveground parts of the plants in the circles were cut,separated into the live and dead samples,and the dry matter(DM)measured.The amount of chlorophylls was also determined.The results indicated a positive correlation between the amounts of chlorophylls and estimated live biomass of the mountainous pastures,but the high amounts of chlorophylls in the meadow pastures disturbed the estimation of the biomass using the NDVI meter.