Studies on dynamics monitor and sustainable development in eastern edge of Qinghai-Tibetan alpine 3/grassland-grass biomass and nutritive dynamics in 8 main grassland types
ZHAO Zhong 1, WANG An lu 2, MA Hai sheng 1, SONG Hui qin 1 (1. Gansu Animal Husbandry Science and Technology Centre, Lanzhou 730030, China; 2. Luqu Animal Husbandry Bureau of Gansu Province, Luqu 747200, China)
Dynamics of grass biomass was monitored and measured during continuous 3 years on 8 representative grassland types in eastern edge of Qinghai Tibetan alpine grassland, which were Elymus nutans Kobresia humilistype, Stipa aliena K. capillifolia + Carex crebratype, Pentaphylloides fruticosa K. bellardiitype, K. tibetica+C. coriophoratype, Polygonum viviparum+ K. capillifoliatype, Salix cuplaris - K. capillifoliatype, Sibiraea angustata- K. capillifoliatype and Brachypodium sylvaticum -Carex crebratype. The results showed that the dynamics of accumulated grass biomass above-ground was accorded with the Logistic curve line, the dynamics of decline was accorded with Y=a+bX model. June to July were best time of biomass accumulation. However, the top yield was appeared in late August. Water and temperature were dominant factors affecting the primary productivity. The contents of course protein, course fiber and course fat were closely related to growing seasons. The trends of DE and NND were similar to those of plant biomass.