维普中文期刊产品整合服务

Effects of grazing intensity on seed production of Caragana stenophylla along a climatic aridity gradient in the Inner Mongolia Steppe,China

查看全文 作  者:XIE [1,2]Lina;CHEN [2]Weizhong;Christopher A [3]GABLER;HAN [2]Lei;GUO [2]Hongyu;CHEN [2]Qing;MA [2]Chengcang;GU [1]Song 高影响力作者 机构地区:[1]College of Life Sciences,Nankai University;[2]Tianjin Key Laboratory of Animal and Plant Resistance,College of Life Sciences,Tianjin Normal University;[3]Department of Biology and Biochemistry,University of Houston高影响力机构 出  处:《Journal of Arid Land》索引2016年第8卷第6期,共9页高影响力期刊 基  金:supported by the National Natural Science Foundation of China(31570453,31170381,31270502,31300386);the PhD Candidate Research Innovation Fund of Nankai University;the Doctoral Fund of Tianjin Normal University(52XB1208) 摘  要:As the increases of climatic aridity and grazing intensity,shrubs play an increasingly important role in grassland ecosystem in arid and semi-arid regions,and its abundance also generally increases.However,the effects of climatic aridity and grazing intensity on sexual reproduction of shrubs in grassland remain largely unclear.In order to understand the effects of grazing intensity and climatic drought stress,and their interaction on seed production of shrub species,we examined the seed number,seed weight and seed yield of Caragana stenophylla under three grazing intensities(fenced,mild grazing and severe grazing) across a climatic aridity gradient(semi-arid,arid,very arid and intensively arid zones) in the Inner Mongolia Steppe,northern China during 2012–2013.The seed number,seed weight and seed yield gradually increased from the semi-arid to the very arid zones,but decreased from the very arid to the intensively arid zones in fenced plots.The seed number and seed yield decreased from the semi-arid to the intensively arid zones in mild and severe grazing treatment plots,therefore,grazing enhanced the suppression effect of climatic aridity on seed production of C.stenophylla.The seed number and seed yield gradually decreased as grazing intensity increased.The seed weight was highest in severe grazing plots,followed by the mild grazing plots and then the fenced plots.Precipitation varied interannually during the study period.We observed that the seed number,seed weight and seed yield were lower in the low precipitation year(2013) than in the high precipitation year(2012).As climatic drought stress increased,the negative effects of grazing on seed production of C.stenophylla also gradually increased.Our results indicated that climatic drought stress may contribute to the encroachment of C.stenophylla shrub in arid zones by promoting its seed production.However,grazing had negative effects on sexual reproduction of C.stenophylla,and the combined effects of drought stress and grazing seriously suppressed sexual reproduction of C.stenophylla in the intensively arid zone. 关 键 词:牧草种子生产 内蒙古草原 气候干旱 放牧强度 生产强度 梯度 中国 草地生态系统
相关文献

参考文献(40)

引证文献(6)

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费