草业学报2017，Vol.26Issue(2)：43-52,10.DOI:10.11686/cyxb2016130
阴山扁蓿豆光合特性对模拟牦牛、藏羊践踏和降水的短期响应
Short-term photosynthetic responses of Medicago ruthenia var.inschanicus to simulated yak and Tibetan sheep trampling and rainfall
摘要
Abstract
To determine the effects of yak and Tibetan sheep trampling and rainfall on the photosynthetic characteristics of Medicago ruthenia var.inschanicus,the responses of single leaf area,chlorophyll content (SPAD value),and photosynthetic gas exchange parameters to short simulated yak and Tibetan sheep trampling and rainfall were studied with a two-factor (simulated trampling and rainfall) controlled experiment in a Tianzhu alpine meadow.The single leaf area,SPAD value,transpiration rate (Tr),stomatal conductance (Gs),and net photosynthetic rate (Pn) decreased with increasing yak and Tibetan sheep trampling intensity and declining rainfall,while the intracellular concentration of CO2 (Ci) increased.Under the same rainfall conditions,the Tr,Gs,and Pn were all higher under a light trampling intensity of Tibetan sheep and yaks than in the control (no trampling),while the Ci was lower than that in the control.The magnitude of decreases in the single leaf area,SPAD value,Tr,Gs,and Pn,and increases in Ci were greater under heavy trampling by yaks than under heavy trampling by Tibetan sheep.Simulated rainfall alone or simulated trampling alone significantly affected the tested indicators,and the interaction between simulated rainfall and simulated trampling had a significant effect on single leaf area,Tr,Gs,Pn,and SPAD value (at the final trampling stage) of M.ruthenia var.inschanicus.These results showed that the photosynthesis of M.ruthenia var.inschanicus was promoted by light trampling,but inhibited by heavy trampling by Tibetan sheep and yaks.Compared with Tibetan sheep,yaks had stronger inhibitory effects on the photosynthetic activity of M.ruthenia var.inschanicus.关键词
阴山扁蓿豆/光合特性/模拟牦牛、藏羊践踏/模拟降水/高寒草甸Key words
Medicago ruthenia var.inschanicus/photosynthetic characteristics/simulated yak and Tibetan sheep trampling/simulated rainfall/alpine meadow引用本文复制引用
肖红,徐长林,张德罡,张建文,杨海磊,柴锦隆,潘涛涛,王艳,鱼小军..阴山扁蓿豆光合特性对模拟牦牛、藏羊践踏和降水的短期响应[J].草业学报,2017,26(2):43-52,10.基金项目
国家自然科学基金(31360570)资助. （31360570）
