西藏高寒草地对氮添加的时间稳定性响应：从群落组成的视角

doi:10.1016/j.jia.2024.07.034

摘要/Abstract

摘要：

沿着环境梯度变化植物群落组成通常会呈现渐变。然而，目前大多数实验研究都集中在单个群落上，在环境梯度上外源养分输入如何影响植物群落的时间稳定性仍不清楚。我们沿着西藏高原北部的降雨梯度，在四种高寒草地（高寒荒漠草原，ADS；高寒草原，AS；高寒草甸草原，AMS；高寒草甸，AM）中进行了为期8年的氮添加实验，并采用双因子方差分析方法研究了氮添加对不同高寒草地群落时间稳定性的影响。我们发现，随着氮添加梯度的升高群落地上生物量在高寒草甸和高寒草甸草原中呈现饱和趋势，高寒草原没有任何变化，而在高寒荒漠草原地上生物量则逐渐增加。不同类型高寒草地群落时间稳定性表现出不同的模式：随着氮梯度的升高，高寒荒漠草原和高寒草甸草原的时间稳定性呈逐渐下降趋势，而在高寒草甸草原则呈单峰趋势。然而，氮添加量对高寒草原群落时间稳定性没有显著影响。优势种稳定性是降雨梯度上高寒草地群落时间稳定性变化的主要控制因素，而物种异步性对时间稳定性的影响则随着降雨量的减少而逐渐增大。这些研究结果表明，在环境梯度上群落组成尤其是优势种，可以介导氮输入对群落时间稳定性的影响。因此，保护和恢复优势物种对群落时间稳定性的维持具有重要的意义。

Abstract:

Plant community composition typically undergoes progressive changes along environmental gradients. However, most experimental studies have focused on individual communities, so it remains unclear how exogenous nutrient inputs affect the stability of plant communities along environmental gradients. Along a rainfall gradient on the northern Tibetan Plateau, we conducted an 8-year nitrogen (N) addition experiment in four alpine grasslands: alpine desert steppe (ADS), alpine steppe (AS), alpine meadow steppe (AMS), alpine meadow (AM), and we used two-way ANOVA to examine the effects of N addition on the temporal stability of these different alpine grasslands. We found that community aboveground biomass showed saturation trends in AM and AMS with increasing N gradients, while there was no change in AS and a gradual increase in ADS. The temporal stability showed different patterns of gradual decreases in ADS and AM, and a unimodal trend in AMS with increasing N gradients. However, N addition had no effect on the temporal stability of AS. Dominant species stability was the controlling factor for alpine grasslands along the transect, while the effect of asynchrony gradually increased with decreasing precipitation. These findings highlight that community composition, especially the dominant species, along the environmental gradient can mediate the effects of N inputs on community temporal stability. Thus, the conservation and restoration of the dominant species are particularly important under future scenarios of increased atmospheric N deposition.

Key words: community composition , dominant species , environmental gradient , plant abundance groups , Tibetan Plateau

Ning Zong, Peili Shi. 西藏高寒草地对氮添加的时间稳定性响应：从群落组成的视角[J]. Journal of Integrative Agriculture, 2025, 24(3): 871-884.

Ning Zong, Peili Shi. Temporal stability responses to nitrogen addition in Tibetan alpine grasslands: A community composition perspective[J]. Journal of Integrative Agriculture, 2025, 24(3): 871-884.

参考文献

Aber J, McDowell W, Nadelhoffer K, Magill A, Berntson G, Kamakea M, McNulty S, Currie W, Rustad L, Fernandez I. 1998. Nitrogen saturation in temperate forest ecosystems - Hypotheses revisited. Bioscience, 48, 921–934.

Bowman W D, Cleveland C C, Halada Ĺ, Hreško J, Baron J S. 2008. Negative impact of nitrogen deposition on soil buffering capacity. Nature Geoscience, 1, 767–770.

Chen H, Zhu Q, Peng C, Wu N, Wang Y, Fang X, Gao Y, Zhu D, Yang G, Tian J, Kang X, Piao S, Ouyang H, Xiang W, Luo Z, Jiang H, Song X, Zhang Y, Yu G, Zhao X, et al. 2013. The impacts of climate change and human activities on biogeochemical cycles on the Qinghai-Tibetan Plateau. Global Change Biology, 19, 2940–2955.

Clark C M, Tilman D. 2008. Loss of plant species after chronic low-level nitrogen deposition to prairie grasslands. Nature, 451, 712–715.

Donohue I, Hillebrand H, Montoya J M, Petchey O L, Pimm S L, Fowler M S, Healy K, Jackson A L, Lurgi M, McClean D, O’Connor N E, O’Gorman E J, Yang Q. 2016. Navigating the complexity of ecological stability. Ecology Letters, 19, 1172–1185.

Du E, Terrer C, Pellegrini A F A, Ahlstrom A, van Lissa C J, Zhao X, Xia N, Wu X, Jackson R B. 2020. Global patterns of terrestrial nitrogen and phosphorus limitation. Nature Geoscience, 13, 221–226.

Galloway J N, Dentener F J, Capone D G, Boyer E W, Howarth R W, Seitzinger S P, Asner G P, Cleveland C C, Green P A, Holland E A, Karl D M, Michaels A F, Porter J H, Townsend A R, Vöosmarty C J. 2004. Nitrogen cycles: Past, present, and future. Biogeochemistry, 70, 153–226.

Gruber N, Galloway J N. 2008. An earth-system perspective of the global nitrogen cycle. Nature, 451, 293–296.

Hautier Y, Seabloom E W, Borer E T, Adler P B, Harpole W S, Hillebrand H, Lind E M, MacDougall A S, Stevens C J, Bakker J D, Buckley Y M, Chu C, Collins S L, Daleo P, Damschen E I, Davies K F, Fay P A, Firn J, Gruner D S, Jin V L, et al. 2014. Eutrophication weakens stabilizing effects of diversity in natural grasslands. Nature, 508, 521–525.

Hou G, Shi P, Zhou T, Sun J, Zong N, Song M, Zhang X. 2023. Dominant species play a leading role in shaping community stability in the Northern Tibetan grasslands. Journal of Plant Ecology, 16, rtac110.

Hou G, Zhou T, Sun J, Zong N, Shi P, Yu J, Song M, Zhu J, Zhang Y. 2022. Functional identity of leaf dry matter content regulates community stability in the northern Tibetan grasslands. Science of the Total Environment, 838, 156150.

Huang M, Liu X, Zhou S. 2020. Asynchrony among species and functional groups and temporal stability under perturbations: Patterns and consequences. Journal of Ecology, 108, 2038–2046.

Isbell F, Craven D, Connolly J, Loreau M, Schmid B, Beierkuhnlein C, Bezemer T M, Bonin C, Bruelheide H, de Luca E, Ebeling A, Griffin J N, Guo Q, Hautier Y, Hector A, Jentsch A, Kreyling J, Lanta V, Manning P, Meyer S T, et al. 2015. Biodiversity increases the resistance of ecosystem productivity to climate extremes. Nature, 526, 574–577.

Jia X, Tao D, Ke Y, Li W, Yang T, Yang Y, He N, Smith M D, Yu Q. 2022. Dominant species control effects of nitrogen addition on ecosystem stability. Science of the Total Environment, 838, 156060.

Jia Y, Yu G, He N, Zhan X, Fang H, Sheng W, Zuo Y, Zhang D, Wang Q. 2014. Spatial and decadal variations in inorganic nitrogen wet deposition in China induced by human activity. Scientific Reports, 4, 3763.

LeBauer D S, Treseder K K. 2008. Nitrogen limitation of net primary productivity in terrestrial ecosystems is globally distributed. Ecology, 89, 371–379.

Lehman C L, Tilman D. 2000. Biodiversity, stability, and productivity in competitive communities. The American Naturalist, 156, 534–552.

Liu J, Li X, Ma Q, Zhang X, Chen Y, Isbell F, Wang D. 2019. Nitrogen addition reduced ecosystem stability regardless of its impacts on plant diversity. Journal of Ecology, 107, 2427–2435.

Loreau M, de Mazancourt C. 2008. Species synchrony and its drivers: Neutral and non-neutral community dynamics in ﬂuctuating environments. The American Naturalist, 172, E48–E66.

Loreau M, de Mazancourt C. 2013. Biodiversity and ecosystem stability: A synthesis of underlying mechanisms. Ecology Letters, 16, 106–115.

Loreau M, Naeem S, Inchausti P, Bengtsson J, Grime J P, Hector A, Hooper D U, Huston M A, Raffaelli D, Schmid B, Tilman D, Wardle D A. 2001. Biodiversity and ecosystem functioning: Current knowledge and future challenges. Science, 294, 804–808.

Lü C, Tian H. 2007. Spatial and temporal patterns of nitrogen deposition in China: Synthesis of observational data. Journal of Geophysical Research: Atmospheres, 112, D22S05.

Ma F, Zhang F, Quan Q, Song B, Wang J, Zhou Q, Niu S. 2021. Common species stability and species asynchrony rather than richness determine ecosystem stability under nitrogen enrichment. Ecosystems, 24, 686–698.

Ma Z, Liu H, Mi Z, Zhang Z, Wang Y, Xu W, Jiang L, He J. 2017. Climate warming reduces the temporal stability of plant community biomass production. Nature Communications, 8, 15378.

Polley H W, Wilsey B J, Derner J D. 2007. Dominant species constrain effects of species diversity on temporal variability in biomass production of tallgrass prairie. Oikos, 116, 2044–2052.

Sasaki T, Lu X, Hirota M, Bai Y. 2019. Species asynchrony and response diversity determine multifunctional stability of natural grasslands. Journal of Ecology, 107, 1862–1875.

Smith B, Wilson J B. 1996. A consumer’s guide to evenness indices. Oikos, 76, 70–82.

Song M, Yu F. 2015. Reduced compensatory effects explain the nitrogen-mediated reduction in stability of an alpine meadow on the Tibetan Plateau. New Phytologist, 207, 70–77.

Song M, Yu F, Ouyang H, Cao G, Xu X, Cornelissen J H C. 2012. Different inter-annual responses to availability and form of nitrogen explain species coexistence in an alpine meadow community after release from grazing. Global Change Biology, 18, 3100–3111.

Song M, Zong N, Jiang J, Shi P, Zhang X, Gao J, Zhou H, Li Y, Loreau M. 2019. Nutrient-induced shifts of dominant species reduce ecosystem stability via increases in species synchrony and population variability. Science of the Total Environment, 692, 441–449.

Tian D, Niu S. 2015. A global analysis of soil acidification caused by nitrogen addition. Environmental Research Letters, 10, 024019.

Tian Q, Lu P, Zhai X, Zhang R, Zheng Y, Wang H, Nie B, Bai W, Niu S, Shi P, Yang Y, Li K, Yang D, Stevens C, Lambers H, Zhang W. 2022. An integrated belowground trait-based understanding of nitrogen-driven plant diversity loss. Global Change Biology, 28, 3651–3664.

Tilman D. 1996. Biodiversity: Population versus ecosystem stability. Ecology, 77, 350–363.

Wang Y, Niu X, Zhao L, Liang C, Miao B, Zhang Q, Zhang J, Schmid B, Ma W. 2020. Biotic stability mechanisms in Inner Mongolian grassland. Proceedings of the Royal Society (B: Biological Sciences), 287, 20200675.

Wang Y, Wang S, Zhao L, Liang C, Miao B, Zhang Q, Niu X, Ma W, Schmid B. 2022. Stability and asynchrony of local communities but less so diversity increase regional stability of Inner Mongolian grassland. eLife, 11, e74881.

Yachi S, Loreau M. 1999. Biodiversity and ecosystem productivity in a fluctuating environment: The insurance hypothesis. Proceedings of the National Academy of Sciences of the United States of America, 96, 1463–1468.

Yang G, Hautier Y, Zhang Z, Lü X, Han X. 2022a. Decoupled responses of above- and below-ground stability of productivity to nitrogen addition at the local and larger spatial scale. Global Change Biology, 28, 2711–2720.

Yang Y, Chen X, Liu L, Li T, Dou Y, Qiao J, Wang Y, An S, Chang S. 2022b. Nitrogen fertilization weakens the linkage between soil carbon and microbial diversity: A global meta-analysis. Global Change Biology, 28, 6446–6461.

Zhang Y, Feng J, Loreau M, He N, Han X, Jiang L. 2019. Nitrogen addition does not reduce the role of spatial asynchrony in stabilising grassland communities. Ecology Letters, 22, 563–571.

Zhang Y, Loreau M, He N, Zhang G, Han X. 2017. Mowing exacerbates the loss of ecosystem stability under nitrogen enrichment in a temperate grassland. Functional Ecology, 31, 1637–1646.

Zhao G, Shi P, Wu J, Xiong D, Zong N, Zhang X. 2017. Foliar nutrient resorption patterns of four functional plants along a precipitation gradient on the Tibetan Changtang Plateau. Ecology and Evolution, 7, 7201–7212.

Zhou B, Li S, Li F, Dong S, Ma F, Zhu S, Zhou H, Stufkens P. 2019. Plant functional groups asynchrony keep the community biomass stability along with the climate change - a 20-year experimental observation of alpine meadow in eastern Qinghai-Tibet Plateau. Agriculture, Ecosystems and Environment, 282, 49–57.

Zhou M, Yang Q, Zhang H, Yao X, Zeng W, Wang W. 2020. Plant community temporal stability in response to nitrogen addition among different degraded grasslands. Science of the Total Environment, 729, 138886.

Zong N, Hou G, Shi P, Song M. 2023. Winter warming alleviates the severely negative effects of nitrogen addition on ecosystem stability in a Tibetan alpine grassland. Science of the Total Environment, 855, 158923.

Zong N, Shi P, Zheng L, Zhou T, Cong N, Hou G, Song M, Tian J, Zhang X, Zhu J. 2021. Restoration effects of fertilization and grazing exclusion on different degraded alpine grasslands: Evidence from a 10-year experiment. Ecological Engineering, 170, 106361.

Zong N, Zhao G, Shi P. 2019. Different sensitivity and threshold in response to nitrogen addition in four alpine grasslands along a precipitation transect on the Northern Tibetan Plateau. Ecology and Evolution, 9, 9782–9793.