Effects of neighborhood tree species diversity on foliar nitrogen-phosphorus stoichiometry of Cunninghamia lanceolata

doi:10.17521/cjpe.2022.0128

Abstract

Abstract:

Aims Biodiversity loss threatens ecosystem functions. Investigating the effect of biodiversity on the ecological stoichiometry of plant nutrients, therefore, can help reveal the mechanisms of the effect of biodiversity on ecosystem functions.

Methods Using a tree species diversity experiment in subtropical China, Cunninghamia lanceolatafrom plots with different tree species richness (1, 4, 8, 16, 32) were selected as focal tree species. The effects of neighborhood species richness (NSR), functional trait dissimilarities between neighborhood tree species and the focal tree, neighborhood competition index (NCI) on foliar nitrogen (N), phosphorus (P) content and N:P of C. lanceolata were investigated.

Important findings (1) The results showed that the dissimilarity in specific root length (SRL_diss) between neighborhood trees and focal trees significantly increased the foliar P content of C. lanceolata, while the dissimilarity in root tissue density (RTD_diss) significantly decreased the foliar N content of C. lanceolata. (2) Neighborhood competition significantly decreased the foliar N content and N:P of C. lanceolata. (3) The interaction effects of NCI and SRL_diss, as well as the interaction between NSR and SRL_diss significantly reduced the foliar P content of C. lanceolata. The result indicates that the positive effect of SRL_diss on the foliar P content of C. lanceolata decreased with increasing NSR, and the positive effect of SRL_diss on the foliar P content of C. lanceolata decreased with increasing NCI. (4) The interaction between NSR and phylogenetic dissimilarity (NP_diss) significantly increased foliar N:P of C. lanceolata, demonstrating that the negative effect of NP_diss on the foliar N:P content of C. lanceolata decreased with increasing NSR. Our results indicated that the foliar P content of C. lanceolata was significantly enhanced by mixing with tree species with different trait dissimilarities, while foliar N content of C. lanceolata was decreased by neighborhood competition. Tree species richness can help mitigate the adverse effects of interspecific competition on C. lanceolata through niche complementation when mixing with species that have greater trait dissimilarity.

Key words: tree species richness, trait dissimilarity, niche complementarity, competition, nutrient

RAN Song-Song, YU Zai-Peng, WAN Xiao-Hua, FU Yan-Rong, ZOU Bing-Zhang, WANG Si-Rong, HUANG Zhi-Qun. Effects of neighborhood tree species diversity on foliar nitrogen-phosphorus stoichiometry of Cunninghamia lanceolata[J]. Chin J Plant Ecol, 2023, 47(7): 932-942.

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Figures/Tables 5

References 66

[1]	Abbas M, Ebeling A, Oelmann Y, Ptacnik R, Roscher C, Weigelt A, Weisser WW, Wilcke W, Hillebrand H (2013). Biodiversity effects on plant stoichiometry. PLoS ONE, 8, e58179. DOI: 10.1371/journal.pone.0058179. DOI URL
[2]	Borer ET, Lind EM, Ogdahl EJ, Seabloom EW, Tilman D, Montgomery RA, Kinkel LL (2015). Food-web composition and plant diversity control foliar nutrient content and stoichiometry. Journal of Ecology, 103, 1432-1441. DOI URL
[3]	Bu WS, Gu HJ, Zhang CC, Zhang Y, Singh AN, Fang XM, Fan J, Wang HM, Chen FS (2020). Mixed broadleaved tree species increases soil phosphorus availability but decreases the coniferous tree nutrient concentration in subtropical China. Forests, 11, 461. DOI: 10.3390/f11040461. DOI URL
[4]	Cadotte M, Albert CH, Walker SC (2013). The ecology of differences: assessing community assembly with trait and evolutionary distances. Ecology Letters, 16, 1234-1244. DOI PMID
[5]	Cardinale BJ, Wright JP, Cadotte MW, Carroll IT, Hector A, Srivastava DS, Loreau M, Weis JJ (2007). Impacts of plant diversity on biomass production increase through time because of species complementarity. Proceedings of the National Academy of Sciences of the United States of America, 104, 18123-18128. DOI PMID
[6]	Chen YX, Wright SJ, Muller-Landau HC, Hubbell SP, Wang YF, Yu SX (2016). Positive effects of neighborhood complementarity on tree growth in a Neotropical forest. Ecology, 97, 776-785. PMID
[7]	Dănescu A, Albrecht AT, Bauhus J (2016). Structural diversity promotes productivity of mixed, uneven-aged forests in southwestern Germany. Oecologia, 182, 319-333. DOI PMID
[8]	de Kroon H, Hendriks M, van Ruijven J, Ravenek J, Padilla FM, Jongejans E, Visser EJW, Mommer L (2012). Root responses to nutrients and soil biota: drivers of species coexistence and ecosystem productivity. Journal of Ecology, 100, 6-15. DOI URL
[9]	Fichtner A, Härdtle W, Bruelheide H, Kunz M, Li Y, von Oheimb G (2018). Neighbourhood interactions drive overyielding in mixed-species tree communities. Nature Communications, 9, 1144. DOI: 10.1038/s41467-018-03529-w. DOI PMID
[10]	Fichtner A, Härdtle W, Li Y, Bruelheide H, Kunz M, von Oheimb G (2017). From competition to facilitation: How tree species respond to neighbourhood diversity. Ecology Letters, 20, 892-900. DOI PMID
[11]	Firn J, Erskine PD, Lamb D (2007). Woody species diversity influences productivity and soil nutrient availability in tropical plantations. Oecologia, 154, 521-533. PMID
[12]	Forrester DI, Bauhus J (2016). A review of processes behind diversity-productivity relationships in forests. Current Forestry Reports, 2, 45-61. DOI URL
[13]	Fort F, Cruz P, Jouany C (2014). Hierarchy of root functional trait values and plasticity drive early-stage competition for water and phosphorus among grasses. Functional Ecology, 28, 1030-1040. DOI URL
[14]	Fortunel C, Valencia R, Wright SJ, Garwood NC, Kraft NJB (2016). Functional trait differences influence neighbourhood interactions in a hyperdiverse Amazonian forest. Ecology Letters, 19, 1062-1070. DOI PMID
[15]	Guiz J, Ebeling A, Eisenhauer N, Hacker N, Hertzog L, Oelmann Y, Roscher C, Wagg C, Hillebrand H (2018). Interspecific competition alters leaf stoichiometry in 20 grassland species. Oikos, 127, 903-914. DOI URL
[16]	Guo QX, Wu XY, Korpelainen H, Li CY (2020). Stronger intra-specific competition aggravates negative effects of drought on the growth of Cunninghamia lanceolata. Environmental and Experimental Botany, 175, 104042. DOI: 10.1016/j.envexpbot.2020.104042. DOI URL
[17]	Hector A, Bazeley-White E, Loreau M, Otway S, Schmid B (2002). Overyielding in grassland communities: testing the sampling effect hypothesis with replicated biodiversity experiments. Ecology Letters, 5, 502-511. DOI URL
[18]	Hegyi F (1974). A simulation model for managing jack-pine stands. Royal College of Forestry, 30, 74-90.
[19]	Hooper DU, Chapin III FS, Ewel JJ, Hector A, Inchausti P, Lavorel S, Lawton JH, Lodge DM, Loreau M, Naeem S, Schmid B, Setälä H, Symstad AJ, Vandermeer J, Wardle DA (2005). Effects of biodiversity on ecosystem functioning: a consensus of current knowledge. Ecological Monographs, 75, 3-35. DOI URL
[20]	Huang Y, Chen Y, Castro-Izaguirre N, Baruffol M, Brezzi M, Lang A, Li Y, Härdtle W, von Oheimb G, Yang X, Liu X, Pei K, Both S, Yang B, Eichenberg D, et al. (2018). Impacts of species richness on productivity in a large-scale subtropical forest experiment. Science, 362, 80-83. DOI PMID
[21]	Huang ZQ, Wan XH, He ZM, Yu ZP, Wang MH, Hu ZH, Yang YS (2013). Soil microbial biomass, community composition and soil nitrogen cycling in relation to tree species in subtropical China. Soil Biology & Biochemistry, 62, 68-75. DOI URL
[22]	Isbell F, Calcagno V, Hector A, Connolly J, Stanley Harpole W, Reich PB, Scherer-Lorenzen M, Schmid B, Tilman D, van Ruijven J, Weigelt A, Wilsey BJ, Zavaleta ES, Loreau M (2011). High plant diversity is needed to maintain ecosystem services. Nature, 477, 199-202. DOI
[23]	Jactel H, Bauhus J, Boberg J, Bonal D, Castagneyrol B, Gardiner B, Gonzalez-Olabarria JR, Koricheva J, Meurisse N, Brockerhoff EG (2017). Tree diversity drives forest stand resistance to natural disturbances. Current Forestry Reports, 3, 223-243. DOI URL
[24]	Kraft NJB, Crutsinger GM, Forrestel EJ, Emery NC (2014). Functional trait differences and the outcome of community assembly: an experimental test with vernal pool annual plants. Oikos, 123, 1391-1399. DOI URL
[25]	Liu C, Xiang WH, Tian DL, Fang X, Peng CH (2011). Overyielding of fine root biomass as increasing plant species richness in subtropical forests in central southern China. Chinese Journal of Plant Ecology, 35, 539-550. DOI URL
	[刘聪, 项文化, 田大伦, 方晰, 彭长辉 (2011). 中亚热带森林植物多样性增加导致细根生物量“超产”. 植物生态学报, 35, 539-550.] DOI
[26]	Liu SR, Yang YJ, Wang H (2018). Development strategy and management countermeasures of planted forests in China: transforming from timber-centered single objective management towards multi-purpose management for enhancing quality and benefits of ecosystem services. Acta Ecologica Sinica, 38, 1-10. DOI URL
	[刘世荣, 杨予静, 王晖 (2018). 中国人工林经营发展战略与对策: 从追求木材产量的单一目标经营转向提升生态系统服务质量和效益的多目标经营. 生态学报, 38, 1-10.]
[27]	Loreau M (2000). Biodiversity and ecosystem functioning: recent theoretical advances. Oikos, 91, 3-17. DOI URL
[28]	Lu HC, Condés S, del Río M, Goudiaby V, den Ouden J, Mohren GMJ, Schelhaas MJ, de Waal R, Sterck FJ (2018). Species and soil effects on overyielding of tree species mixtures in the Netherlands. Forest Ecology and Management, 409, 105-118. DOI URL
[29]	Luo YH, Sun DJ, Lin JY, Guo WF, Lu LH, Wen YG (2013). Effect of Close-to-Nature management on the natural regeneration and species diversity in a masson pine plantation. Acta Ecologica Sinica, 33, 6154-6162. DOI URL
	[罗应华, 孙冬婧, 林建勇, 郭文福, 卢立华, 温远光 (2013). 马尾松人工林近自然化改造对植物自然更新及物种多样性的影响. 生态学报, 33, 6154-6162.]
[30]	Ma WH, Fang JY (2006). The relationship between species richness and productivity in four typical grasslands of northern China. Biodiversity Science, 14, 21-28. DOI
	[马文红, 方精云 (2006). 中国北方典型草地物种丰富度与生产力的关系. 生物多样性, 14, 21-28.] DOI
[31]	Mayfield MM, Levine JM (2010). Opposing effects of competitive exclusion on the phylogenetic structure of communities. Ecology Letters, 13, 1085-1093. DOI PMID
[32]	Mellert KH, Prietzel J, Straussberger R, Rehfuess KE, Kahle HP, Perez P, Spiecker H (2008). Relationships between long-term trends of air temperature, precipitation, nitrogen nutrition and growth of coniferous stands in central Europe and Finland. European Journal of Forest Research, 127, 507-524. DOI URL
[33]	Miller AE, Bowman WD, Suding KN (2007). Plant uptake of inorganic and organic nitrogen: neighbor identity matters. Ecology, 88, 1832-1840. PMID
[34]	Muledi J, Bauman D, Jacobs A, Meerts P, Shutcha M, Drouet T (2020). Tree growth, recruitment, and survival in a tropical dry woodland: the importance of soil and functional identity of the neighbourhood. Forest Ecology and Management, 460, 117894. DOI: 10.1016/j.foreco.2020.117894. DOI URL
[35]	Nickmans H, Collet C, Bonal D, Verheyen K, Ponette Q (2017). Tree size and local neighbourhood affect foliar nutrient content in a mixed plantation of beech (Fagus sylvatica) and maple (Acer pseudoplatanus). Forest Ecology and Management, 400, 159-172. DOI URL
[36]	Oelmann Y, Potvin C, Mark T, Werther L, Tapernon S, Wilcke W (2010). Tree mixture effects on aboveground nutrient pools of trees in an experimental plantation in Panama. Plant and Soil, 326, 199-212. DOI URL
[37]	Paine CET, Norden N, Chave J, Forget PM, Fortunel C, Dexter KG, Baraloto C (2012). Phylogenetic density dependence and environmental filtering predict seedling mortality in a tropical forest. Ecology Letters, 15, 34-41. DOI PMID
[38]	Pan FJ, Zhang W, Liu SJ, Li DJ, Wang KL (2015). Leaf N:P stoichiometry across plant functional groups in the karst region of southwestern China. Trees, 29, 883-892. DOI URL
[39]	Parker IM, Saunders M, Bontrager M, Weitz AP, Hendricks R, Magarey R, Suiter K, Gilbert GS (2015). Phylogenetic structure and host abundance drive disease pressure in communities. Nature, 520, 542-544. DOI
[40]	Piao TF, Comita LS, Jin GZ, Kim JH (2013). Density dependence across multiple life stages in a temperate old-growth forest of northeast China. Oecologia, 172, 207-217. DOI PMID
[41]	Pollastrini M, Nogales AG, Benavides R, Bonal D, Finer L, Fotelli M, Gessler A, Grossiord C, Radoglou K, Strasser RJ, Bussotti F (2017). Tree diversity affects chlorophyll a fluorescence and other leaf traits of tree species in a boreal forest. Tree Physiology, 37, 199-208. DOI PMID
[42]	Reich PB, Tilman D, Isbell F, Mueller K, Hobbie SE, Flynn DFB, Eisenhauer N (2012). Impacts of biodiversity loss escalate through time as redundancy fades. Science, 336, 589-592. DOI PMID
[43]	Richards AE, Forrester DI, Bauhus J, Scherer-Lorenzen M (2010). The influence of mixed tree plantations on the nutrition of individual species: a review. Tree Physiology, 30, 1192-1208. DOI PMID
[44]	Rieger I, Kowarik I, Ziche D, Wellbrock N, Cierjacks A (2019). Linkages between phosphorus and plant diversity in central European forest ecosystems—Complementarity or competition? Forests, 10, 1156. DOI: 10.3390/f10121156. DOI URL
[45]	Roscher C, Schumacher J, Schmid B, Schulze ED (2015). Contrasting effects of intraspecific trait variation on trait- based niches and performance of legumes in plant mixtures. PLoS ONE, 10, e0119786. DOI: 10.1371/journal.pone.0119786. DOI URL
[46]	Setiawan NN, Vanhellemont M, Baeten L, Gobin R, de Smedt P, Proesmans W, Ampoorter E, Verheyen K (2016). Does neighbourhood tree diversity affect the crown arthropod community in saplings? Biodiversity and Conservation, 25, 169-185. DOI URL
[47]	Sheng WT (2018). On the maintenance of long-term productivity of plantation in China. Forest Research, 31(1), 1-14.
	[盛炜彤 (2018). 关于我国人工林长期生产力的保持. 林业科学研究, 31(1), 1-14.]
[48]	Simon J, Li XY, Rennenberg H (2014). Competition for nitrogen between European beech and sycamore maple shifts in favour of beech with decreasing light availability. Tree Physiology, 34, 49-60. DOI PMID
[49]	Simon J, Waldhecker P, Brüggemann N, Rennenberg H (2010). Competition for nitrogen sources between European beech (Fagus sylvatica) and sycamore maple (Acer pseudoplatanus) seedlings. Plant Biology, 12, 453-458. DOI PMID
[50]	Sirami C, Gross N, Baillod AB, Fahrig L (2019). Increasing crop heterogeneity enhances multitrophic diversity across agricultural regions. Proceedings of the National Academy of Sciences of the United States of America, 116, 16442-16447. DOI PMID
[51]	Tilman D, Reich PB, Knops J, Wedin D, Mielke T, Lehman C (2001). Diversity and productivity in a long-term grassland experiment. Science, 294, 843-845. PMID
[52]	Tobner CM, Paquette A, Gravel D, Reich PB, Williams LJ, Messier C (2016). Functional identity is the main driver of diversity effects in young tree communities. Ecology Letters, 19, 638-647. DOI PMID
[53]	Turnbull LA, Isbell F, Purves DW, Loreau M, Hector A (2016). Understanding the value of plant diversity for ecosystem functioning through niche theory. Proceedings of the Royal Society B, 283, 20160536. DOI: 10.1098/rspb.2016.0536. DOI
[54]	Vilà M, Carrillo-Gavilán A, Vayreda J, Bugmann H, Fridman J, Grodzki W, Haase J, Kunstler G, Schelhaas M, Trasobares A (2013). Disentangling biodiversity and climatic determinants of wood production. PLoS ONE, 8, e53530. DOI: 10.1371/journal.pone.0053530. DOI URL
[55]	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. DOI URL
[56]	Wagg C, Ebeling A, Roscher C, Ravenek J, Bachmann D, Eisenhauer N, Mommer L, Buchmann N, Hillebrand H, Schmid B, Weisser WW (2017). Functional trait dissimilarity drives both species complementarity and competitive disparity. Functional Ecology, 31, 2320-2329. DOI URL
[57]	Walker JT, James JJ, Drenovsky RE (2017). Competition from Bromus tectorum removes differences between perennial grasses in N capture and conservation strategies. Plant and Soil, 412, 177-188. DOI URL
[58]	Xu XJ, Timmer VR (1999). Growth and nitrogen nutrition of Chinese fir seedlings exposed to nutrient loading and fertilization. Plant and Soil, 216, 83-91. DOI URL
[59]	Yang X, Thornton PE, Ricciuto DM, Post WM (2014). The role of phosphorus dynamics in tropical forests—A modeling study using CLM-CNP. Biogeosciences, 11, 1667-1681. DOI URL
[60]	Yang YS, Chen GS, Xie JS, He ZM, Chen YX, Huang RZ (2002). Nutrient cycling of N and P by a mixed forest of Cunninghamia lanceolata and Tsoongiodendron odorum in subtropical China. Acta Phytoecologica Sinica, 26, 473-480.
	[杨玉盛, 陈光水, 谢锦升, 何宗明, 陈银秀, 黄荣珍 (2002). 杉木-观光木混交林群落N、P养分循环的研究. 植物生态学报, 26, 473-480.]
[61]	Zemunik G, Turner BL, Lambers H, Laliberté E (2015). Diversity of plant nutrient-acquisition strategies increases during long-term ecosystem development. Nature Plants, 1, 15050. DOI: 10.1038/nplants.2015.50. DOI
[62]	Zeugin F, Potvin C, Jansa J, Scherer-Lorenzen M (2010). Is tree diversity an important driver for phosphorus and nitrogen acquisition of a young tropical plantation? Forest Ecology and Management, 260, 1424-1433. DOI URL
[63]	Zhang P, Pang SJ, Yang BG, Liu SL, Jia HY, Chen JB, Guo DQ (2021). Effects of different mixing patterns on growth, litter production and soil nutrients in Eucalyptus plantations. Journal of Northwest A&F University (Natural Science Edition), 49(2), 31-37.
	[张培, 庞圣江, 杨保国, 刘士玲, 贾宏炎, 陈健波, 郭东强 (2021). 不同混交模式对桉树林分生长、凋落物量和土壤养分的影响. 西北农林科技大学学报(自然科学版), 49(2), 31-37.]
[64]	Zhou J, Li QR, Liu M, Zhou XQ, Song MH, Qiao N, Wang HM, Xu XL (2021). Neighboring tree species alter uptake of NH+ 4 and NO- 3 by Chinese fir. Trees, 35, 459-467. DOI
[65]	Zhu DH, Hui DF, Wang MQ, Yang Q, Yu SX (2020). Light and competition alter leaf stoichiometry of introduced species and native mangrove species. Science of the Total Environment, 738, 140301. DOI: 10.1016/j.scitotenv.2020.140301. DOI URL
[66]	Zou XH, Wu PF, Chen NL, Wang P, Ma XQ (2015). Chinese fir root response to spatial and temporal heterogeneity of phosphorus availability in the soil. Canadian Journal of Forest Research, 45, 402-410. DOI URL

编号 No.	树种丰富度 Species richness	样地重复数 Replicates	树种组成 Tree species composition
A	1	4	杉木 Cunninghamia lanceolata
B	4	3	红锥、杉木、柳杉、米槠 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii
C	4	3	红锥、杉木、福建柏、南方红豆杉 Castanopsis hystrix, Cunninghamia lanceolata, Fokienia hodginsii, Taxus wallichiana var. mairei
D	4	3	杉木、马尾松、南方红豆杉、壳菜果 Cunninghamia lanceolata, Pinus massoniana, Taxus wallichiana var. mairei, Mytilaria laosensis
E	8	3	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica, Manglietia fordiana, Alnus trabeculosa
F	8	3	红锥、杉木、柳杉、米槠、福建柏、南方红豆杉、闽楠、木荷 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba
G	8	3	红锥、杉木、枫香树、马尾松、福建柏、南方红豆杉、苦槠、壳菜果 Castanopsis hystrix, Cunninghamia lanceolata, Liquidambar formosana, Pinus massoniana, Fokienia hodginsii, Taxus wallichiana var. mairei, Castanopsis sclerophylla, Mytilaria laosensis
H	16	4	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木、福建柏、南方红豆杉、闽楠、木荷、红豆树、深山含笑、刨花润楠、浙江楠 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica, Manglietia fordiana, Alnus trabeculosa, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Ormosia hosiei, Michelia maudiae, Machilus pauhoi, Phoebe chekiangensis
I	16	4	红锥、杉木、柳杉、米槠、枫香树、马尾松、枳椇、栓皮栎、福建柏、南方红豆杉、闽楠、木荷、苦槠、壳菜果、鸡爪槭、柯 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Liquidambar formosana, Pinus massoniana, Quercus variabilis, Hovenia acerba, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Castanopsis sclerophylla, Mytilaria laosensis, Acer palmatum, Lithocarpus glaber
J	32	4	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木、福建柏、南方红豆杉、闽楠、木荷、红豆树、深山含笑、刨花润楠、浙江楠、枫香树、马尾松、朴树、栓皮栎、枳椇、黧蒴锥、青钱柳、无患子、苦槠、壳菜果、鸡爪槭、柯、樟、山杜英、紫薇、木樨 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica Manglietia fordiana, Alnus trabeculosa, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Ormosia hosiei, Michelia maudiae, Machilus pauhoi, Phoebe chekiangensis, Liquidambar formosana, Pinus massoniana, Celtis sinensis, Quercus variabilis, Hovenia acerba, Castanopsis fissa, Cyclocarya paliurus, Sapindus saponaria, Castanopsis sclerophylla, Mytilaria laosensis, Acer palmatum, Lithocarpus glaber, Cinnamomum camphora, Elaeocarpus sylvestris, Lagerstroemia indica, Osmanthus fragrans

编号 No.	树种丰富度 Species richness	样地重复数 Replicates	树种组成 Tree species composition
A	1	4	杉木 Cunninghamia lanceolata
B	4	3	红锥、杉木、柳杉、米槠 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii
C	4	3	红锥、杉木、福建柏、南方红豆杉 Castanopsis hystrix, Cunninghamia lanceolata, Fokienia hodginsii, Taxus wallichiana var. mairei
D	4	3	杉木、马尾松、南方红豆杉、壳菜果 Cunninghamia lanceolata, Pinus massoniana, Taxus wallichiana var. mairei, Mytilaria laosensis
E	8	3	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica, Manglietia fordiana, Alnus trabeculosa
F	8	3	红锥、杉木、柳杉、米槠、福建柏、南方红豆杉、闽楠、木荷 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba
G	8	3	红锥、杉木、枫香树、马尾松、福建柏、南方红豆杉、苦槠、壳菜果 Castanopsis hystrix, Cunninghamia lanceolata, Liquidambar formosana, Pinus massoniana, Fokienia hodginsii, Taxus wallichiana var. mairei, Castanopsis sclerophylla, Mytilaria laosensis
H	16	4	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木、福建柏、南方红豆杉、闽楠、木荷、红豆树、深山含笑、刨花润楠、浙江楠 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica, Manglietia fordiana, Alnus trabeculosa, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Ormosia hosiei, Michelia maudiae, Machilus pauhoi, Phoebe chekiangensis
I	16	4	红锥、杉木、柳杉、米槠、枫香树、马尾松、枳椇、栓皮栎、福建柏、南方红豆杉、闽楠、木荷、苦槠、壳菜果、鸡爪槭、柯 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Liquidambar formosana, Pinus massoniana, Quercus variabilis, Hovenia acerba, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Castanopsis sclerophylla, Mytilaria laosensis, Acer palmatum, Lithocarpus glaber
J	32	4	红锥、杉木、柳杉、米槠、醉香含笑、野鸦椿、木莲、江南桤木、福建柏、南方红豆杉、闽楠、木荷、红豆树、深山含笑、刨花润楠、浙江楠、枫香树、马尾松、朴树、栓皮栎、枳椇、黧蒴锥、青钱柳、无患子、苦槠、壳菜果、鸡爪槭、柯、樟、山杜英、紫薇、木樨 Castanopsis hystrix, Cunninghamia lanceolata, Cryptomeria japonica var. sinensis, Castanopsis carlesii, Michelia macclurei, Euscaphis japonica Manglietia fordiana, Alnus trabeculosa, Fokienia hodginsii, Taxus wallichiana var. mairei, Phoebe bournei, Schima superba, Ormosia hosiei, Michelia maudiae, Machilus pauhoi, Phoebe chekiangensis, Liquidambar formosana, Pinus massoniana, Celtis sinensis, Quercus variabilis, Hovenia acerba, Castanopsis fissa, Cyclocarya paliurus, Sapindus saponaria, Castanopsis sclerophylla, Mytilaria laosensis, Acer palmatum, Lithocarpus glaber, Cinnamomum camphora, Elaeocarpus sylvestris, Lagerstroemia indica, Osmanthus fragrans

编号 No.	树种丰富度 Species richness	重复数 Replicate	目标树高 Focal tree height (m)	目标树地径 Focal tree ground diameter (mm)	平均树高 Mean tree heigh (m)	平均地径 Mean ground diameter (mm)
A	1	4	1.4 ± 0.2	25 ± 4.2	1.1 ± 0.1	18 ± 1.6
B	4	3	1.4 ± 0.3	27 ± 6.0	1.2 ± 0.2	19 ± 1.1
C	4	3	1.5 ± 0.3	26 ± 5.4	1.2 ± 0.2	19 ± 1.6
D	4	3	1.4 ± 0.2	23 ± 3.2	1.4 ± 0.2	21 ± 1.4
E	8	3	1.6 ± 0.3	28 ± 5.3	1.3 ± 0.2	19 ± 1.6
F	8	3	1.4 ± 0.4	27 ± 8.1	1.2 ± 0.1	19 ± 0.9
G	8	3	1.6 ± 0.3	29 ± 6.0	1.2 ± 0.2	19 ± 1.6
H	16	4	1.5 ± 0.2	26 ± 4.6	1.2 ± 0.1	18 ± 1.5
I	16	4	1.3 ± 0.2	26 ± 3.8	1.1 ± 0.1	17 ± 1.4
J	32	4	1.4 ± 0.2	25 ± 4.9	1.2 ± 0.1	18 ± 1.4

编号 No.	树种丰富度 Species richness	重复数 Replicate	目标树高 Focal tree height (m)	目标树地径 Focal tree ground diameter (mm)	平均树高 Mean tree heigh (m)	平均地径 Mean ground diameter (mm)
A	1	4	1.4 ± 0.2	25 ± 4.2	1.1 ± 0.1	18 ± 1.6
B	4	3	1.4 ± 0.3	27 ± 6.0	1.2 ± 0.2	19 ± 1.1
C	4	3	1.5 ± 0.3	26 ± 5.4	1.2 ± 0.2	19 ± 1.6
D	4	3	1.4 ± 0.2	23 ± 3.2	1.4 ± 0.2	21 ± 1.4
E	8	3	1.6 ± 0.3	28 ± 5.3	1.3 ± 0.2	19 ± 1.6
F	8	3	1.4 ± 0.4	27 ± 8.1	1.2 ± 0.1	19 ± 0.9
G	8	3	1.6 ± 0.3	29 ± 6.0	1.2 ± 0.2	19 ± 1.6
H	16	4	1.5 ± 0.2	26 ± 4.6	1.2 ± 0.1	18 ± 1.5
I	16	4	1.3 ± 0.2	26 ± 3.8	1.1 ± 0.1	17 ± 1.4
J	32	4	1.4 ± 0.2	25 ± 4.9	1.2 ± 0.1	18 ± 1.4

	变量 Variable	系数 Estimate	标准误 SE	df	t	p	R²m	R²c
叶片氮含量 Foliar N content	截距 Intercept	2.87	0.02	66.4	184.16	<0.001	0.05	0.20
叶片氮含量 Foliar N content	NSR	0.03	0.02	55.0	1.83	0.073
	NCI	-0.03	0.01	263.0	-2.06	0.04
	RTD_diss	-0.04	0.02	93.5	-2.30	0.024
叶片磷含量 Foliar P content	截距 Intercept	-0.05	0.02	134.6	-2.45	0.016	0.17	0.29
叶片磷含量 Foliar P content	NSR	0.03	0.02	123.9	1.26	0.212
	NCI	0.02	0.02	263.4	0.92	0.361
	SRL_diss	0.05	0.02	191.1	1.98	0.049
	NSR × SRL_diss	-0.05	0.02	87.6	-2.40	0.018
	NCI × SRL_diss	-0.05	0.02	263.8	-2.25	0.026
叶片氮磷比 Foliar N:P	截距 Intercept	2.89	0.03	159.0	114.09	<0.001	0.16	0.33
叶片氮磷比 Foliar N:P	NSR	0.02	0.31	168.8	0.61	0.546
	NCI	-0.05	0.02	263.8	-2.90	0.004
	NP_diss	-0.06	0.03	228.5	-1.90	0.059
	NSR × NP_diss	0.07	0.02	108.3	2.69	0.008
	NCI × NP_diss	0.04	0.02	251.7	1.58	0.116