三江源区高寒草甸植物种群生态位对返青期休牧时间的响应  

Response of Ecological Niche of Alpine Meadow Population to Rest Grazing Time During Green Period in Three-River Source Region

作　　者：宋志萍 王晓丽[1] 王彦龙[1] 周选博 谢乐乐 SONG Zhi-ping;WANG Xiao-li;WANG Yan-long;ZHOU Xuan-bo;XIE Le-le(Academy of Animal Science and Veterinary Medicine, Qinghai University, Xining, Qinghai Province 810000, China)

机构地区：[1]青海大学畜牧兽医科学院,青海西宁810000

出　　处：《草地学报》2022年第7期1651-1658,共8页Acta Agrestia Sinica

基　　金：国家自然科学基金区域联合基金(U21A20183,U21A20186);国家自然科学基金项目(31700454);中国科学院-青海省人民政府-三江源国家公园联合研究专项(LHZX-2020-08)资助。

摘　　要：为研究返青期休牧对高寒草甸物种生态位的影响,在果洛州玛沁县高寒草甸设置5个休牧时间,即0 d(放牧),20 d,30 d,40 d和50 d,连续两年监测并计算各处理下主要物种重要值。同时,将休牧时间作为环境梯度,研究返青期休牧对植物物种生态位宽度和重叠度的影响。结果表明:与放牧相比,重要值增加最显著的是乳白香青(Anaphalis lactea)和垂穗披碱草(Elymus nutans),分别增加了455.6%,106.3%;高山嵩草(Kobresia pygmaea)(0.997)、细叶亚菊(Ajania tenuifolia)(0.995)、双柱头藨草(Scirpus distigmaticus)(0.993)的生态位宽度最高;高山嵩草和肉果草(Lancea tibetica)(0.997)、高山嵩草和草地早熟禾(Poa pratensis)(0.996)、双柱头藨草和高山嵩草(0.996)、垂穗披碱草和草地早熟禾(0.995)的生态位重叠度最高。休牧40 d促进莎草科和禾本科植物的生长,抑制毒害草的生长发育。因此,高寒草甸的物种重要值越高,其物种生态位宽度往往也越大。We studied the effects of rest grazing on plant niches in an alpine meadow.In the study,five rest-grazing periods in the spring were set and named 0 d(grazing),20 d,30 d,40 d,and 50 d in Maqin County,Guoluo Prefecture,then we monitored and calculated the importance values of major species in plant communities under various grazing treatments for two consecutive years.Simultaneously,we studied the effects of resting grazing time on niche width and niche overlap of alpine meadow plant species by using rest grazing time as the environmental gradient.The results showed that:Compared with grazing,the most significant increase in importance value was Anaphalis lactea and Elymus nutans,which increased by 455.6%and 106.3%.The niche widths of Kobresia pygmaea(0.997),Ajania tenuifolia(0.995),and Scirpus distigmaticus(0.993)were the highest;The top three niche overlap values were Kobresia pygmaea and Lancea tibetica(0.997),Kobresia pygmaea and Poa pratensis(0.996),Scirpus distigmaticus and Kobresia pygmaea(0.996),Elymus nutans and Poa pratensis(0.995).It can be seen that under the treatment of 40 days of rest grazing,the growth of cyperaceae and poaceae plants was promoted,while the growth and development of poisonous weeds were inhibited.Therefore,the species with higher importance values tended to have large niche width.

关 键 词：高寒草甸 物种重要值 返青期休牧 生态位宽度 生态位重叠 

分 类 号：S812.8[农业科学—草业科学]