模拟践踏和降水对高寒草甸阴山扁蓿豆有性繁殖特征的影响  

Effects of simulated trampling and rainfall on sexual reproduction characteristics of Medicago ruthenica var. inschanica on alpine meadow

作　　者：肖红[1] 徐长林[1] 张德罡[1] 柴锦隆 潘涛涛[1] 鱼小军[1] XIAO Hong;XU Chang-lin;ZHANG De-gang;CHAI Jin-long;PAN Tao-tao;YU Xiao-jun(Pratacultural College, Gansu Agricultural University, Key Laboratory of Grassland Ecosystem of Ministry of Education, Sino-U.S. Centers for Grazing Land Ecosystem Sustainability, Pratacultural Engineering Laboratory of Gansu Province, Lanzhou 730070, China)

机构地区：[1]甘肃农业大学草业学院草业生态系统教育部重点实验室中美草地畜牧业可持续发展研究中心甘肃省草业工程实验室,兰州730070

出　　处：《生态学杂志》2018年第7期1976-1982,共7页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(31360570)资助

摘　　要：在甘肃天祝高寒草甸进行了为期2年的野外试验,研究了模拟牦牛和藏羊践踏(藏羊轻度践踏、藏羊中度践踏、藏羊重度践踏、牦牛轻度践踏、牦牛中度践踏、牦牛重度践踏)及模拟降水量(少雨、平水和丰水)对阴山扁蓿豆有性繁殖特性的影响。结果表明:阴山扁蓿豆株高、荚果长、单位面积荚果数、每荚果种子数、种子千粒重和种子产量均随牦牛和藏羊践踏强度的增加、降水量的降低呈下降趋势;少雨条件下,重度践踏单位面积荚果数较未践踏降低70%以上;牦牛和藏羊践踏下的种子千粒重比未践踏减少13%以下;少雨条件下,藏羊轻度、中度和重度践踏下的阴山扁蓿豆种子产量分别比同强度牦牛践踏高60.1%、13.8%和56.7%;降水、践踏及两者的交互作用均极显著影响了植株自然高度;降水和践踏均极显著影响了阴山扁蓿豆荚果长、单位面积荚果数、每荚果种子数、种子千粒重,两者的交互作用则无显著影响。综上,同一放牧强度下,牦牛践踏对阴山扁蓿豆有性繁殖的不利影响大于藏羊践踏;少雨和家畜重度践踏均严重抑制了阴山扁蓿豆的有性繁殖。A two-year field experiment was conducted to examine the effects of simulated yak and Tibetan sheep trampling（ light,moderate,and heavy trampling） and simulated rainfall（ low,average,and high） on sexual reproduction of Medicago ruthenica var. inschanica in a Tianzhu alpine meadow in Gansu Province. The results showed that the plant height,pod length,number of pods per square meter,seed number per pod,1000-grain weight and seed yield of M. ruthenica decreased with the increases of trampling intensity and the decreases of rainfall. Under low rainfall level,heavy trampling decreased the pod number per square meter by 70% than un-trampling. The 1000-grain weight of M. ruthenica seeds under trampling was 13% lower than that of un-trampling. Under low rainfall level,the seed yield of M. ruthenica under light,moderate,and heavy trampling of Tibetan sheep was 60.1%,13.8% and 56.7% higher than that under corresponding intensity of yak trampling,respectively. Rainfall,trampling and their interaction showed significant effects on the height of M. ruthenica. Moreover,rainfall and trampling significantly affected the sexual reproduction indices of M. ruthenica; however,their interaction effect was not statistically significant. Overall,the negative effect of yak trampling on M. ruthenica sexual reproduction was higher than that of Tibetan sheep under same trampling intensity. The sexual reproduction of M. ruthenica was inhibited by low rainfall level and heavy trampling.

关 键 词：牦牛 藏羊 践踏 降水 阴山扁蓿豆 有性繁殖 

分 类 号：S541[农业科学—作物学]