Grazing filtering effect based on intraspecific and interspecific trait variation and its scale effects

doi:10.17521/cjpe.2023.0358

Abstract

Abstract:

Aims Grazing is the primary human disturbance in grassland ecosystems and serves as a key external filtering factor in the grassland community assembly. However, the specific mechanisms about the influence of grazing intensity on community assembly in grasslands, particularly the relative roles of intraspecific and interspecific trait variation, remain unclear. This study systematically analyzed the responses of aboveground (shoots and leaves) and belowground (roots) plant traits to grazing, and examined the filtering effect of grazing intensity by considering intraspecific and interspecific trait variation at two spatial scales: from the auger coring to plot scale, and from the plot to site scale.
Methods In this study, we conducted field investigation based on a long-term grazing manipulation experiment in a typical steppe in Nei Mongol, China. Samples of plant aboveground parts and root systems were acquired at the individual plant level using the auger coring method. The filtering effects of grazing intensity were assessed at both the auger coring and plot scales. Furthermore, we explored the regulatory mechanisms of soil moisture and nutrients on grazing filtration.
Important findings (1) Intraspecific and interspecific variations in most aboveground traits tended to increase with higher grazing intensity, they were opposite in root traits. (2) At the auger coring scale, the filtering intensity of grazing based on intraspecific variation and interspecific variation of aboveground traits initially increased, peaked at moderate grazing intensity, and then decreased. However, the filtering intensity based on intraspecific and interspecific variations of root traits consistently increased. At the plot scale, the filtering intensity of grazing based on intraspecific and interspecific variations of aboveground traits linearly decreased; the grazing filtration intensity based on intraspecific variation of roots traits increased, while the grazing filtration intensity based on interspecific differences weakened. (3) As the spatial scale increased, the influence of grazing intensity on grassland community assembly shifted from filtering based on interspecific trait variation to filtering based on intraspecific trait variation. This shift was regulated by soil moisture and nutrient availability. These findings provide new insights into the regulatory mechanisms of grazing on grassland community assembly and provide important bases for understanding vegetation landscape heterogeneity and assessing scale effects resulting from long-term grazing. There were certain limitations in this study, where leaf and root traits mainly focused on structural characteristics. we could integrate chemical traits, such as leaf and root carbon and nitrogen contents, to comprehensively exploring the regulatory mechanisms of grazing on the variation of aboveground and belowground plant traits in future studies.

Key words: plant functional trait, intraspecific variation, interspecific variation, community assembly, grazing intensity, environmental filtering, scale effect, typical steppe

QIN Jia-Chen, WANG Huan, ZHU Jiang, WANG Yang, TIAN Chen, BAI Yong-Fei, YANG Pei-Zhi, ZHENG Shu-Xia. Grazing filtering effect based on intraspecific and interspecific trait variation and its scale effects[J]. Chin J Plant Ecol, 2024, 48(7): 858-871.

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Figures/Tables 8

Fig. 1 Effects of grazing intensity on intraspecific (σIC2) and interspecific (σPC2) trait variation at the auger coring scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second, and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 2 Effects of grazing intensity on intraspecific (σIC2) and interspecific (σPC2) trait variation at the plot scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 3 Effect of grazing filtration based on intraspecific trait variation (TIC/IR) at the auger coring scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 4 Effect of grazing filtration based on interspecific trait variation (TPC/PR) at the auger coring scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 5 Effect of grazing filtration based on intraspecific trait variation (TIC/IR) at the plot scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 6 Effect of grazing filtration based on interspecific trait variation (TPC/PR) at the plot scale in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots; LA, leaf area; PB, plant individual aboveground biomass; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd and SRL-3rd represent the specific root length of the first, second and third order roots.

Fig. 7 Effects of grazing intensity on soil water and nutrients in Nei Mongol typical steppe.

Fig. 8 Correlations between plant traits (TIC/IR and TPC/PR) and soil properties at the auger coring (A) and plot (B) scales in Nei Mongol typical steppe. ARD-1st, ARD-2nd and ARD-3rd represent the average diameter of the first, second and third order roots. LA, leaf area; PB, aboveground biomass of plants; PH, plant height; SLA, specific leaf area; SRL-1st, SRL-2nd, and SRL-3rd represent the specific root length of the first, second and third order roots. Soil properties: SOC, soil organic carbon content; STN, total soil nitrogen content; STP, total soil phosphorus content; SWC, soil water content. TIC/IR, effect of grazing filtration based on intraspecific trait variation; TPC/PR, effect of grazing filtration based on interspecific trait variation. +, p < 0.1; *, p < 0.05; **, p < 0.01.

References 45

[1]	Bai YF, Han XG, Wu JG, Chen ZZ, Li LH (2004). Ecosystem stability and compensatory effects in the Inner Mongolia grassland. Nature, 431, 181-184.
[2]	Bai YF, Wu JG, Pan QM, Huang JH, Wang QB, Li FS, Buyantuyev A, Han XG (2007). Positive linear relationship between productivity and diversity: evidence from the Eurasian Steppe. Journal of Applied Ecology, 44, 1023-1034.
[3]	Bolnick DI, Amarasekare P, Araújo MS, Bürger R, Levine JM, Novak M, Rudolf VHW, Schreiber SJ, Urban MC, Vasseur DA (2011). Why intraspecific trait variation matters in community ecology. Trends in Ecology & Evolution, 26, 183-192.
[4]	Cuchillo-Hilario M, Wrage-Mönnig N, Isselstein J (2018). Forage selectivity by cattle and sheep co-grazing swards differing in plant species diversity. Grass and Forage Science, 73, 320-329.
[5]	Des Roches S, Post DM, Turley NE, Bailey JK, Hendry AP, Kinnison MT, Schweitzer JA, Palkovacs EP (2018). The ecological importance of intraspecific variation. Nature Ecology & Evolution, 2, 57-64.
[6]	Diamond JM (1975). Assembly of species communities//Cody ML, Diamond JM. Ecology and Evolution of Communities. Harvard University Press, Cambridge, USA. 342-444.
[7]	Díaz S, Cabido M, Casanoves F (1998). Plant functional traits and environmental filters at a regional scale. Journal of Vegetation Science, 9, 113-122.
[8]	Díaz S, Lavorel S, McIntyre S, Falczuk V, Casanoves F, Milchunas DG, Skarpe C, Rusch G, Sternberg M, Noy-Meir I, Landsberg J, Zhang W, Clark H, Campbell BD (2007). Plant trait responses to grazing—A global synthesis. Global Change Biology, 13, 313-341.
[9]	Díaz S, Noy-Meir I, Cabido M (2001). Can grazing response of herbaceous plants be predicted from simple vegetative traits? Journal of Applied Ecology, 38, 497-508.
[10]	Eldridge DJ, Delgado-Baquerizo M, Travers SK, Val J, Oliver I (2017). Do grazing intensity and herbivore type affect soil health? Insights from a semi-arid productivity gradient. Journal of Applied Ecology, 54, 976-985.
[11]	Funk JL, Larson JE, Ames GM, Butterfield BJ, Cavender-Bares J, Firn J, Laughlin DC, Sutton-Grier AE, Williams L, Wright J (2017). Revisiting the Holy Grail: using plant functional traits to understand ecological processes. Biological Reviews, 92, 1156-1173.
[12]	Grime JP (2006). Trait convergence and trait divergence in herbaceous plant communities: mechanisms and consequences. Journal of Vegetation Science, 17, 255-260.
[13]	Gross N, Börger L, Soriano-Morales SI, Le Bagousse-Pinguet Y, Quero JL, García-Gómez M, Valencia-Gómez E, Maestre FT (2013). Uncovering multiscale effects of aridity and biotic interactions on the functional structure of Mediterranean shrublands. Journal of Ecology, 101, 637-649.
[14]	Guo DL, Li H, Mitchell RJ, Han WX, Hendricks JJ, Fahey TJ, Hendrick RL (2008). Fine root heterogeneity by branch order: exploring the discrepancy in root turnover estimates between minirhizotron and carbon isotopic methods. New Phytologist, 177, 443-456. DOI PMID
[15]	Hodge A (2004). The plastic plant: root responses to heterogeneous supplies of nutrients. New Phytologist, 162, 9-24.
[16]	Hoffmann C, Giese M, Dickhoefer U, Wan HW, Bai YF, Steffens M, Liu CY, Butterbach-Bahl K, Han XG (2016). Effects of grazing and climate variability on grassland ecosystem functions in Inner Mongolia: synthesis of a 6-year grazing experiment. Journal of Arid Environments, 135, 50-63.
[17]	Huang DH, Chen ZZ (1986). Preliminary observation on root distribution depth of 49 species of plants in Xilin Gol sandy grassland, Inner Mongolia. Chinese Journal of Grassland, 8(2), 31-32.
	[黄德华, 陈佐忠 (1986). 内蒙古锡林郭勒沙地草场49种植物根系分布深度的初步观察. 中国草原, 8(2), 31-32.]
[18]	Kumar A, Shahbaz M, Koirala M, Blagodatskaya E, Seidel SJ, Kuzyakov Y, Pausch J (2019). Root trait plasticity and plant nutrient acquisition in phosphorus limited soil. Journal of Plant Nutrition and Soil Science, 182, 945-952.
[19]	Li TL, Huo GW, Wu YN (2022). Comparison of root traits of Stipa krylovii and Allium polyrhizum under grazing in typical steppe. Chinese Journal of Applied Ecology, 33, 360-368.
	[李天良, 霍光伟, 乌云娜 (2022). 放牧影响下典型草原克氏针茅和多根葱根系属性比较. 应用生态学报, 33, 360-368.] DOI
[20]	Li WH, Xu FW, Zheng SX, Taube F, Bai YF (2017). Patterns and thresholds of grazing-induced changes in community structure and ecosystem functioning: species-level responses and the critical role of species traits. Journal of Applied Ecology, 54, 963-975.
[21]	Lu XY, Kelsey KC, Yan Y, Sun J, Wang XD, Cheng GW, Neff JC (2017). Effects of grazing on ecosystem structure and function of alpine grasslands in Qinghai-Tibetan Plateau: a synthesis. Ecosphere, 8, e01656. DOI: 10.1002/ecs2.1656.
[22]	Luo WT, Wu YN, Zhang FJ, Huo GW, Lü JZ (2011). Root characteristics under different grazing intensities in Stipa krylovii steppe. Chinese Journal of Ecology, 30, 2692-2699.
	[雒文涛, 乌云娜, 张凤杰, 霍光伟, 吕建洲 (2011). 不同放牧强度下克氏针茅(Stipa krylovii)草原的根系特征. 生态学杂志, 30, 2692-2699.]
[23]	Maynard DS, Serván CA, Capitán JA, Allesina S (2019). Phenotypic variability promotes diversity and stability in competitive communities. Ecology Letters, 22, 1776-1786. DOI PMID
[24]	Meng TT, Ni J, Wang GH (2007). Plant functional traits, environments and ecosystem functioning. Journal of Plant Ecology (Chinese Version), 31, 150-165.
	[孟婷婷, 倪健, 王国宏 (2007). 植物功能性状与环境和生态系统功能. 植物生态学报, 31, 150-165.] DOI
[25]	Niu K, He J, Lechowicz MJ (2016). Grazing-induced shifts in community functional composition and soil nutrient availability in Tibetan alpine meadows. Journal of Applied Ecology, 53, 1554-1564.
[26]	Pakeman RJ, Fielding DA (2021). Increased grazing drives homogenisation but reduced grazing increases turnover in upland habitat mosaics. Biodiversity and Conservation, 30, 4279-4295.
[27]	Shan YM, Chen DM, Guan XX, Zheng SX, Chen HJ, Wang MJ, Bai YF (2011). Seasonally dependent impacts of grazing on soil nitrogen mineralization and linkages to ecosystem functioning in Inner Mongolia grassland. Soil Biology & Biochemistry, 43, 1943-1954.
[28]	Shi T, Cao J, Yan RR, Yan YC, Zhang YX, Wang X, Xin XP (2023). Effects of mowing on soil microbial stoichiometry in meadow grassland. Soil and Fertilizer Sciences in China, (3), 127-134.
	[石田, 曹娟, 闫瑞瑞, 闫玉春, 张煜星, 王旭, 辛晓平 (2023). 刈割对草甸草原土壤微生物化学计量特征的影响. 中国土壤与肥料, (3), 127-134.]
[29]	Siefert A, Ravenscroft C, Althoff D, Alvarez-Yépiz JC, Carter BE, Glennon KL, Heberling JM, Jo IS, Pontes A, Sauer A, Willis A, Fridley JD (2012). Scale dependence of vegetation-environment relationships: a meta-analysis of multivariate data. Journal of Vegetation Science, 23, 942-951.
[30]	Stein A, Gerstner K, Kreft H (2014). Environmental heterogeneity as a universal driver of species richness across taxa, biomes and spatial scales. Ecology Letters, 17, 866-880. DOI PMID
[31]	Sun D, Wesche K, Chen D, Zhang S, Wu G, Du G, Comerford NB (2011). Grazing depresses soil carbon storage through changing plant biomass and composition in a Tibetan alpine meadow. Plant, Soil and Environment, 57, 271-278.
[32]	Tong C, Wu J, Yong S, Yang J, Yong W (2004). A landscape-scale assessment of steppe degradation in the Xilin River Basin, Inner Mongolia, China. Journal of Arid Environments, 59, 133-149.
[33]	Violle C, Enquist BJ, McGill BJ, Jiang L, Albert CH, Hulshof C, Jung V, Messier J (2012). The return of the variance: intraspecific variability in community ecology. Trends in Ecology & Evolution, 27, 244-252.
[34]	Violle C, Navas ML, Vile D, Kazakou E, Fortunel C, Hummel I, Garnier E (2007). Let the concept of trait be functional! Oikos, 116, 882-892.
[35]	Wan H, Bai Y, Schönbach P, Gierus M, Taube F (2011). Effects of grazing management system on plant community structure and functioning in a semiarid steppe: scaling from species to community. Plant and Soil, 340, 215-226.
[36]	Wang CN, Li X, Lu XM, Wang Y, Bai YF (2023). Intraspecific trait variation governs grazing-induced shifts in plant community above- and below-ground functional trait composition. Agriculture, Ecosystems & Environment, 346, 108357. DOI: 10.1016/j.agee.2023.108357.
[37]	Wang J, Wang D, Li C, Seastedt TR, Liang C, Wang L, Sun W, Liang M, Li Y (2018). Feces nitrogen release induced by different large herbivores in a dry grassland. Ecological Applications, 28, 201-211. DOI PMID
[38]	Weiher E, Paul Clarke GD, Keddy PA (1998). Community assembly rules, morphological dispersion, and the coexistence of plant species. Oikos, 81, 309-322.
[39]	Xu B, Zhao HL, Xu H, Liu YX (2000). Twinspan analysis of plant community composition under experimental grazing in a sandy grassland. Acta Phytoecologica Sinica, 24, 252-256.
	[徐斌, 赵哈林, 徐浩, 刘寅虓 (2000). 沙地草场放牧试验植物群落的TWINSPAN数量分析. 植物生态学报, 24, 252-256.]
[40]	Zhang B, Hautier Y, Tan X, You C, Cadotte MW, Chu C, Jiang L, Sui X, Ren T, Han X, Chen S (2020). Species responses to changing precipitation depend on trait plasticity rather than trait means and intraspecific variation. Functional Ecology, 34, 2622-2633.
[41]	Zhao M, Zhao K, Wang YB, Yin GM, Liu SB, Yan BL, Meng WJ, Lyu SJ, Han GD (2023). Long-term grazing disturbance reduced plant diversity in Stipa breviflora desert steppe. Acta Prataculturae Sinica, 32(9), 39-49.
	[赵敏, 赵坤, 王赟博, 殷国梅, 刘思博, 闫宝龙, 孟卫军, 吕世杰, 韩国栋 (2023). 长期放牧干扰降低了短花针茅荒漠草原植物多样性. 草业学报, 32(9), 39-49.] DOI
[42]	Zheng SX, Chi YG, Yang XJ, Li WH, Lan ZC, Bai YF (2022). Direct and indirect effects of nitrogen enrichment and grazing on grassland productivity through intraspecific trait variability. Journal of Applied Ecology, 59, 598-610.
[43]	Zheng SX, Lan ZC, Li WH, Shao RX, Shan YM, Wan HW, Taube F, Bai YF (2011). Differential responses of plant functional trait to grazing between two contrasting dominant C₃ and C₄ species in a typical steppe of Inner Mongolia, China. Plant and Soil, 340, 141-155.
[44]	Zheng SX, Ren HY, Lan ZC, Li WH, Wang KB, Bai YF (2010). Effects of grazing on leaf traits and ecosystem functioning in Inner Mongolia grasslands: scaling from species to community. Biogeosciences, 7, 1117-1132.
[45]	Zhou GY, Zhou XH, Nie YY, Bai SH, Zhou LY, Shao JJ, Cheng WS, Wang JW, Hu FQ, Fu YL (2018). Drought-induced changes in root biomass largely result from altered root morphological traits: evidence from a synthesis of global field trials. Plant, Cell & Environment, 41, 2589-2599.