金强河流域不同退化草地牧草营养成分研究

以天祝县金强河流域高山草甸中的冬季草场的不同退化样地为研究对象，在试验室条件下测定了牧草的粗蛋白、粗脂肪、粗纤维、粗灰分、无氮浸出物等指标，并用总可消化养分（TDN）综合比较了各退化样地间差异。分析结果表明：（1）不同退化阶段的草地营养呈现出退化趋势，未退化样地牧草粗蛋白含量为14．1％，中度退化样地为11．1％，极度退化样地为6．4％左右；（2）随草地的退化，TDN下降明显，各样地间鲜草产量和TDN均呈现出”低-高-低”的变化趋势。由此可知适度利用草地，可以促进草地萌发，改善牧草的产量和营养，相反若持续过度利用，草地质量则会严重下降。

The Component of Pasture Nutrition in Different Deteriorated Grasslands in the Jinqiang Rive Drainage Area

The different samples of deteriorated grassland in winter alpine meadow grassland in the Jinqiang Rive drainage area of Tianzhu County were taken as study objects, the indices (crude protein, crude fat, crude fiber, crude ash and nitrogen-free extract (NFE), etc.) of pasture were determined under the condition of laboratory, and the differences between each samples of deteriorated grassland were comprehensively compared by total digestible nutrition (TDN). The results indicated that the pasture nutrition in different deteriorated stages showed a degenerative tendency that the crude protein contents of pasture in the samples of non-deteriorated grassland, medium-deteriorated grassland and extreme-deteriorated grassland were 14.1%, 11.1% and around 6.4%, respectively; TDN obviously reduced with the degeneration of grassland, and the yield and TDN of fresh grass in every samples of grassland all showed a tendency of low - high -low. Therefore, utilizing grassland moderately can promote the germination of grassland and increase the yield and nutrition of pasture, or the quality of grassland will reduce badly.