厦门大学学报（自然科学版）2025，Vol.64Issue(3)：423-432,10.DOI:10.6043/j.issn.0438-0479.202411019
梯度增温对色季拉山高寒草甸植物物种多样性与生产力的影响
Effects of gradient warming on plant species diversity and productivity of alpine meadows of the Sygera Mountains
摘要
Abstract
[Objective]Investigate the effects of climate warming on the species diversity and productivity of plant communities in alpine meadow ecosystems.[Methods]Using the alpine meadow of the Sygera Mountain as research site,an open-top air chamber(OTC)warming device was employed.Six warming gradients(CK,T1,T2,T3,T4,T5)were randomly set up in a sample plot of 50 m×50 m for one-year experiments,to investigate the microenvironments,the responses of plant community composition,biomass,and species diversity under different warming levels.The microenvironment was continuously and dynamically monitored using temperature and humidity logger records(0-10 cm)and button type temperature and humidity sensors(0-10 cm).Plant community composition was investigated and biomass was collected in August during the peak plant growing season.Aboveground biomass was obtained by manual cutting and mowing,while below ground biomass was collected by root auger drilling at depths of 0-10 cm,＞10-20 cm,and＞20-30 cm.Roots were separated using an 80-mesh soil sieve,rinsed,and air-dried.Finally,both aboveground and underground samples were dried in an oven at 65℃ to a constant mass,so as to obtain the aboveground and underground biomass.[Results]1)Under warming treatments,air temperature increased by 1.96,2.19,2.26,2.28 and 2.43℃,and soil temperature increased by 0.52,0.92,0.96,1.46 and 1.76℃ during the peak growing season(August).Air-soil humidity showed a decreasing trend with increasing temperature,with the largest air humidity reducion under T5 treatment,compared to CK(7.25％),and a significant soil humidity decrease under T4 treatment compared to CK(10.24％).2)Community cover and height were significantly reduced(P＜0.05)under intense warming(T5).Although species composition did not change significantly with increasing temperature,the Shannon-Weiner index decreased under T5 treatment compared to CK,while the other warming treatments showed varying degrees of increase.The Margalef richness index under moderate warming(T3)was significantly higher(P＜0.05)than that under CK,while the Shannon-Weiner index under T5 was significantly lower(P＜0.05)than that under other treatments.3)Under the warming treatments,the aboveground biomass and total biomass under T2 were significantly higher(P＜0.05)than those under T5,reaching 291.28 and 598.08 g/m2,respectively.Aboveground biomass and total biomass were significantly reduced(P＜0.05)under heightened warming,and the propertion of biomass allocated to belowground parts was highest under T5(71.12％).4)Air-soil temperature was significantly positively correlated with species diversity(P＜0.05),and strongly significantly negatively correlated with community coverage degree(P＜0.01).Soil moisture was significantly negatively correlated with aboveground biomass(P＜0.05),which may be due to the high degree of warming forcing the soil water content to decrease,inhibiting plant growth and leading to a decrease in plant community cover,reducing aboveground biomass and total biomass.[Conclusion]A one-year warming experiment in the alpine meadow of Sygera Mountain revealed that warming in the peak growing season(August)led to a small increase in air-soil temperature,a large decrease in surface soil moisture,and a warm drying of soil microenvironment.The number of species was higher under the warming treatments compared to CK,but the community height and coverage degree showed a decreasing trend.Among different warming treatments,species diversity of the T5 treatment was more sensitive to the response than that of T1-T3,suppressing the accumulation of aboveground biomass.Except for the T3 treatment,all warming treatments promoted belowground biomass production,with T5 exhibiting the highest belowground biomass allocation.In conclusion,short-term warming changed the microhydrothermal conditions of alpine meadow plant communities in the Sygera Mountain.Moderate warming(T1-T3)enhanced species diversity and biomass accumulation,while intense warming(T5)led to a decrease in soil water content,which inhibited plant growth and biomass production.关键词
增温/高寒草甸/物种多样性/生产力/微气候Key words
warming/alpine meadow/species diversity/productivity/microclimate分类
生物学引用本文复制引用
杨小菊,孙雪婷,胡旭,罗大庆,扎西次仁,吴虹皓,屈兴乐..梯度增温对色季拉山高寒草甸植物物种多样性与生产力的影响[J].厦门大学学报（自然科学版）,2025,64(3):423-432,10.基金项目
西藏农牧学院青年科研基金(NYQNKY2023-04) （NYQNKY2023-04）
西藏农牧学院研究生创新计划项目(YJS2023-03) （YJS2023-03）
第二次青藏高原综合科学考察研究项目(2019QZZK1006) （2019QZZK1006）
西藏农牧学院林学博士点(一期)(533325001) （一期）
