碌曲县天然草原资源及可食牧草养分含量评价OA

To accurately assess the productivity and nutritional dynamics of natural grasslands in Luqu county on the eastern margin of the Qinghai-Tibet Plateau,this study conducted field surveys during the growing season(June-August)on two main grassland types(alpine meadow and mountain meadow).By integrating laboratory analy-sis,geographic information technology,and the relative feed value(RFV)index,the study systematically measured for-age yield,nutrient content,and spatial distribution.Livestock carrying capacity was evaluated based on both dry matter and digestible crude protein(CP)yield.The results indicate that alpine meadow dominates the study area(accounting for 60.21％of the total).During the growing season,hay yield continued to increase while CP content decreased:the county's total hay yield rose from 493 900 t in June to 1 010 200 t in August,while CP content decreased from 13.83％to 11.70％,and the RFV index dropped by approximately 27.6％.Livestock carrying capacity assessment revealed that accounting result based on digestible CP was 0.24 sheep unit/hm2 lower than that based on dry matter on average,with phosphorus(P)identified as the limiting nutrient across the region.Spatial analysis further identified Langmusi town as a high-yield area for CP.In conclusion,this study suggests that carrying capacity evaluation for natural grasslands in Luqu county should shift from a"dry matter balance"approach to a"nutritional balance"framework,implementing zoned precision management strategies focused on protein and phosphorus supplementation,so as to promote grass-livestock balance and ecological conservation.