不同放牧方式对高寒草地功能群生态化学计量特征的影响  

Effects of Different Livestock Assembly on the Stoichiometry of Alpine Grassland Functional Groups

作　　者：冯斌 杨晓霞 刘文亭 董全民[1,2] 张春平 刘玉祯 孙彩彩 李彩弟 时光 杨增增 张小芳 魏琳娜[2,3] FENG Bin;YANG Xiao-xia;LIU Wen-ting;DONG Quan-min;ZHANG Chun-ping;LIU Yu-zhen;SUN Cai-cai;LI Cai-di;SHI Guang;Yang Zeng-zeng;ZHANG Xiao-fang;WEI Lin-na(Academy of Animal Science and Veterinary Medicine, Qinghai University/Qinghai Academy of Animal and Veterinary Science, Xining, Qinghai Province 810016, China;Qinghai Provincial Key Laboratory of Adaptive Management on Alpine Grassland, Qinghai University, Xining, Qinghai Province 810016, China;College of Agriculture and Animal Husbandry, Qinghai University, Xining, Qinghai Province 810016, China)

机构地区：[1]青海大学畜牧兽医科学院,青海省畜牧兽医科学院,青海西宁810016 [2]青海大学青海省高寒草地适应性管理重点实验室,青海西宁810016 [3]青海大学农牧学院,青海西宁810016

出　　处：《草地学报》2022年第5期1063-1070,共8页Acta Agrestia Sinica

基　　金：青海省科技厅创新平台建设专项(2020-ZJ-T07);国家自然基金项目(31772655);国家自然科学基金联合基金项目(U20A2007)资助。

摘　　要：本研究基于青藏高原东北部高寒草甸化草原设置的控制放牧试验,测定牦牛单牧(YG)、藏羊单牧(SG)、牦牛藏羊1∶6混牧(MG1∶6)、牦牛藏羊1∶4混牧(MG1∶4)、牦牛藏羊1∶2混牧(MG1∶2)和禁牧对照(NG)下禾本科、莎草科、豆科和杂类草的C,N,P含量并计算分析其计量特征。结果表明:各放牧处理增加了禾本科和莎草科的N含量,降低了杂类草的C含量,此外仅YG处理增加了莎草科的P含量;各放牧处理降低了禾本科和莎草科牧草的C∶N,除YG降低了莎草科的C∶P和N∶P以外,其他放牧处理增加了C∶P和N∶P;不同放牧方式下各功能群C∶N,C∶P,N∶P与N,P具有显著的负相关性(P<0.05)。依据中度放牧干扰下植物超补偿性生长的机制和植被生长速率假说,YG促进了莎草科物种的生长,同时也表明N、P在促进植被更新方面起到了重要的作用,是高寒草地植被生长重要的限制性元素。The stability of the Qinghai-Tibet Plateau ecosystem is of great significance to global climate regulation and the maintenance of biodiversity.The response of contents and stoichiometry of carbon(C),nitrogen(N)and phosphorus(P)of plant functional groups to different livestock assembly under moderate grazing is important to reveal the utilization,distribution and balance of C,N and P among plant functional groups under grazing management.The experiment treatments included:only yak grazing(YG),only Tibetan sheep grazing(SG),yak and Tibetan sheep grazing mixed as 1∶6(MG1∶6),yak and Tibetan sheep grazing mixed as 1∶4(MG1∶4),yak and Tibetan sheep grazing mixed as 1∶2(MG1∶2)and no grazing for control(NG).The element contents and their stoichiometry of four plant functional groups(Poaceae,Cyperaceae,Fabaceae and forb)were measured through a manipulated grazing experiment on an alpine grassland.The results showed that∶All grazing treatments increased the N content of Poaceae and Cyperaceae,but decreased the C content of forb.Besides,YG increased the P content of Cyperaceae.All grazing treatments decreased C∶N of Poaceae and Cyperaceae.YG decreased whereas the other grazing treatments increased C∶P and N∶P of Cyperaceae.It showed a significantly negative correlation among C∶N,C∶P,N∶P and the contents of N,P for each functional group under all treatments(P<0.05).YG promotes the growth of Cyperaceae,meanwhile it shows that N and P play an important role in promoting vegetation regeneration and may restrict plant growth in alpine grassland based on the mechanism of super-compensatory growth of plant under moderate grazing and growth-rate hypothesis.

关 键 词：中度放牧 高寒草地 功能群 生态化学计量特征 放牧方式 

分 类 号：S812[农业科学—草业科学]