不同放牧强度下矮嵩草无性系构件组成量化研究

对不同放牧强度下 ( 0 ,2 ,4 ,8只 /hm2 二龄藏羊 )高寒草甸矮嵩草无性系构件组成进行了数量化研究。结果表明 ,随着放牧强度的增加 ,单位面积无性系内矮嵩草分株数、分蘖数、叶片数量及其营养分蘖和生殖分蘖生物量呈减少趋势 ;矮嵩草分蘖节距地面高度略有加深 ,而平均分蘖节直径变化规律不明显 ;生殖分株种子数和分蘖种子数有较明显的增加 ,在重牧区开始减少。随着放牧强度的增加 ,矮嵩草无性系营养和生殖分株生物量以中牧区为最大 ,分别是 6 9 133mg和 91 76 6mg。无性系大小对矮嵩草构件数量和生物量的影响随着放牧强度的增加逐渐减弱

Quantitatively study on the clonal composition of Kobresia humilis under different stocking intensities

The clonal composition and growth of Kobresia humilis under different stocking intensities (0,2,4,8 sheeps/hm 2 ) were studied in Alpine Meadow. The results showed that the numbers of ramet, tillers, leaves, its vegetative tillers and biomass of flowering ramet under standard unit (1cm 2 ) decreased as the increase of stock intensity. The height under the ground of average tiller nodes was appreciably deepened but the diameter of tiller nodes was not obviously changed. From the heavy degenerative gradation, the seed numbers of the flowering ramet and vegetative tiller were increased.The aboveground biomass of vegetative and flowering ramet of clonal K. humulis for medial degenerative gradation were maximal value, which were 69 133mg and 91 766mg,respectively. The effect of big and small clonal K.humulis on its component numbers and biomass was gradually weakened as the increase of stock intensity.