火烧后草原植物营养和热值的变化

研究了不同时间不同频次的草原火烧后，植物体内营养含量和热值的变化。表明，割草地火烧后当年羊草体内营养含量普遍高于割草未烧地，但随着生长季的推进，火烧地羊草体内Ｎ、Ｃａ、Ｃ的含量逐渐低于未烧地，大针芭也表出出与间 草相似的变化规律，只是在生长季后期，未烧地大针茅体内粗纤维含量高于火烧地，火烧后翌年，烧地羊草体内除粗纤维外，未烧地大针茅体内粗纤维含量高于火烧地。火烧后翌年，火烧地羊草体内除粗纤维外，其

Response of nutrient and caloric value in grassland plant following burning

Changes in plant nutrient content and caloric value following grassland burning in various time and frequencies were studied. In the same year of burning in field mown and burned, the nutrient content in Aneurolepidium chinese generally grew higher than that of unburned field. But with the proceeding of growth season, the contents of N, Ca and C in Aneurolepidium chinese in burned field went gradually down lower that that of unburned field. The changing pattern of nutrient content in Stipa grandis was nearly similar to Aneurolepidium chinese, only in late stage of growth period the content of coarse fiber in Stipa grandis of unburned field exceeded that of burned field. In the second year following burning, the nutrient content in Aneurolepidium chinese of burned field was still higher than that of unburned field, except for coarse fiber. In field burned in spring and autumn. The nutrient content in Aneurolepidium chinese generally went down. As for the elements in Aneurolepidium Chinese, burning increased the contents of Zn, Mn, K, Ca and Mg, decreased the contents of Na and P, exerted an irregular influence on the contents of Fe, Cu and Al. In the same year of burning, the caloric value of Aneurolepidium chinese decreased,that of Stipa grandis increased, that of community mixture increased. Generally speaking,proper burning could be adopted to be a tool to increase the nutrient content and caloric value of grassland plants.