摘要
【目的】揭示禁牧处理对西藏亏祖山温性草原优势植物群落中主要植物物种的生态位和种间联结的影响,为青藏高原温性草原植物多样性保护和科学管理提供理论依据。【方法】采用“Levins”方法、方差比率法(V_(r))、卡方检验、联结系数(A_(c))和Ochiai(O_(i))指数,对亏祖山温性草原优势植物群落中的8个主要植物物种进行分析。【结果】(1)禁牧增加了草沙蚕(Tripogon bromoides)、高山嵩草(Carex parvula)、白草(Pennisetum flaccidum)和丝颖针茅(Stipa capillacea)的生态位宽度和生态位重叠值。(2)研究区内禁牧处理的群落总体表现为负关联(V_(r)=0.43),自然放牧群落总体表现为正关联(V_(r)=1.21);χ^(2)检验表明8个优势物种所组成的28个种对在禁牧和自然放牧处理下分别有67.9%和53.6%的种对表现出负联结性;联结系数Ac值表明,禁牧和自然放牧处理下分别有50%和42.9%的种对均呈负联结;禁牧使得优势种(草沙蚕、高山嵩草、白草和丝颖针茅)之间的Oi指数增大。【结论】禁牧使亏祖山温性草原优势植物群落内种间竞争加强,种间关系变紧密,群落结构趋于不稳定。
[Objective]In order to reveal the effects of non-grazing restriction on ecological niches and interspecific associations of the herbaceous species in the dominant plant communities in the temperate grasslands of the Kuizu Mountains in Linzhou County,Tibet,and to provide theoretical basis for the protection of plant diversity in the temperate grasslands in the Tibetan Plateau and for scientific management of the grasslands.[Methods]The“Levins”method,variance ratio method(V_(r)),Chi-square test,association coefficient(A_(c)),and Ochiai(O_(i))index were used to analyze eight major plant species in the dominant plant communities in the temperate grasslands of the Kuizu Mountains in Tibet.[Results](1)Non-grazing treatments increased the niche width and niche overlap of grass sedge(Tripogon bromoides),alpine tarragon(Carex parvula),whitegrass(Pennisetum flaccidum),and silky needle fescue(Stipa capillacea).(2)The enclosure community in the study area showed an overall negative association(V_(r)=0.43),and the free-grazing community showed an overall positive association(V_(r)=1.21).According to the Chi square test,67.9%and 53.6%of the 28 species pairs composed of 8 dominant species displayed negative association under the non-grazing and free grazing treatments,respectively.The association coefficient showed that 50%and 42.9%of species pairs were negatively linked under the non-grazing and free grazing treatments,respectively.The non-grazing treatments increased the Oi values of the main species,including Tripogon bromoides,Carex parvula,Pennisetum flaccidum,and Stipa capillacea.[Conclusion]Based on the interspecific association analysis,non-grazing treatments strengthened inter-species competition within the dominant plant communities in the temperate grasslands in the Kuizu Mountains,and the inter-species relationships become closer with unstable community structures.
作者
杨金涛
张晓晗
尹正辉
桑旦群培
古桑群宗
YANG Jintao;ZHANG Xiaohan;YIN Zhenghui;SANGDAN Qunpei;GUSANG Qunzong(College of Science,Tibet University,Lhasa 850000,China;First Medium Occupation Technical School of Lhasa City,Lhasa 850000,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2024年第2期330-337,共8页
Acta Botanica Boreali-Occidentalia Sinica
基金
西藏大学2022年国家级大学生创新训练计划项目(202210694005)。
关键词
禁牧
亏祖山
生态位
种间联结
non-grazing
Kuizu Mountains
ecological niche
interspecific association
