不同放牧率下小花碱茅可溶性碳水化合物和氮素含量的变化

Changes of the content of water-soluble carbohydrate and nitrogen in Puccinellia tenuiflora under different stocking rates

在东北松嫩草原上通过小区围栏放牧,对不同放牧率下小花碱茅可溶性碳水化合物和氮素含量的变化进行了分析。结果表明,小花碱茅在生长季初期茎基部的可溶性碳水化合物含量最低,随着季节推移逐渐增加;一定程度的放牧有利于牧草可溶性碳水化合物的提高,促进牧草再生。氮素含量在生长季初期最大,然后随季节推移逐渐降低;适当放牧能够刺激根对土壤中氮素的吸收,使其向地上部分转移,提高牧草的营养价值。

Changes of the content of watersoluble carbohydrate and nitrogen in P.tenuiflora under different stocking rates were studied by grazing experiment on Songnen grassland in the northeast of China. The results indicated that the content of watersoluble carbohydrate in base stem of P.tenuiflora was lowest at the beginning of growth period, then it increased gradually with the seasons. Proper stocking rates were favorable for the increase of watersoluble carbohydrate and could accelerate the regrowth of herbage. The content of nitrogen was highest at the beginning of growth period, then it decreased gradually with the seasons. Proper stocking rates could stimulate the assimilation for nitrogen in soil and bring it to the aboveground part, which improved the nutrient value of herbage.