模拟牦牛和藏羊践踏与降水对矮生嵩草根系营养物质含量的影响

Effect of Simulated Yak and Tibetan Sheep Trampling and Rainfall on Nutrients Content in Kobresia humilis Root

在高山草甸进行模拟牦牛和藏羊践踏与降水双因子调控试验,探究矮生嵩草根系营养物质含量对模拟牦牛和藏羊践踏强度与降水的响应。结果发现,随着模拟践踏强度(牦牛和藏羊)的增加,矮生嵩草根系还原糖、可溶性蛋白、可溶性糖、淀粉及粗蛋白质含量均呈先升后降趋势。在相同践踏强度下,随着模拟降水量的下降,矮生嵩草根系可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质含量均呈下降趋势。3个水分处理下,牦牛和藏羊中度践踏下矮生嵩草根系物质含量(可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质)均显著高于对照(P<0.05)。丰水处理下,牦牛和藏羊践踏下矮生嵩草根系营养物质含量均显著高于同等践踏强度下少雨处理(P<0.05)。丰水和缺水处理下,牦牛中度践踏下矮生嵩草根系可溶性糖和可溶性蛋白含量显著高于藏羊中度践踏处理。少雨、平水和丰水处理下,藏羊重度践踏处理下根系还原糖、淀粉和粗蛋白质含量均显著高于牦牛重度践踏处理(P<0.05)。模拟践踏和降水共同作用对矮生嵩草根系可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质的影响均达极显著水平。综合可得,适度的牦牛和藏羊践踏有利于根系营养物质的积累,少雨和重度践踏会抑制根系营养物质的积累。

In order to providing a basis for the reasonable management and utilization of alpine meadow,the effects of trampling of yak and Tibetan sheep and rainfall on nutrients content in Kobresia humilis root were studied with a two factors（simulated trampling and rainfall）controlled experiment in Tianzhu alpine meadow.The results showed that the content of reducing sugar,soluble protein,soluble sugar,starch and crude protein increased firstly then decreased with increasing yak and Tibetan sheep trampling intensity.Each index showed the trend of decline under the same intensity with simulated precipitation decreasing.Under the three rainfall treatment（lower,average and high level of rainfall）,the starch content（reducing sugar,soluble protein,soluble sugar,starch and crude protein）of K.humilis under the moderate trampling of yaks and Tibetan sheep was significantly higher than that of CK（P〈0.05）.Contrary to the treatment of higher rainfall,the content of the root matter under yak and Tibetan sheep same trample intensity was significantly decreased under the lower rainfall（P〈0.05）.Under the treatment of lower and higher rainfall,the content of soluble sugar and soluble protein in the K.humilis root under yak moderate trampling was significantly higher than that under the Tibetan sheep moderate trampling.Under the three rainfall treatment（lower,average and high level of rainfall）,the contents of reducing sugar,starch and crude protein under the Tibetan sheep heavy trampling intensity was significant higher than yak heavy trampling intensity（P〈0.05）.The interaction between simulated rainfall and simulated trampling had significant effect on reducing sugar,soluble protein,soluble sugar,starch and crude protein of K.humilis.Moderate yak and Tibetan sheep trampling are beneficial to the accumulation of K.humilis root nutritive material,and contrary to the lower rainfall and heavy trampling intensity.