Effects of topography and stand structure of warm temperate deciduous broad-leaved forest on understory herb diversity in Donglingshan, Beijing

doi:10.17520/biods.2022671

Abstract

Abstract:

Aim: Topographic and stand structure are important factors affecting species diversity of understory communities. Our objective was to explore the effects of different topographic factors and forest stand structure on the species diversity of herbaceous plants in a warm temperate deciduous broad-leaved forest.

Methods: Based on the survey data of 450 1 m × 1 m herbaceous plots in the 20 ha Donglingshan forest dynamics plot, Beijing, we used species richness index, Shannon-Wiener diversity index, Simpson dominance index and Pielou evenness index as the indicators of herbaceous species diversity to analyze the changes of each diversity index with different factors of topographic and forest stand structure. Meanwhile, we utilized Pearson correlation analysis, regression analysis, redundancy analysis (RDA), and hierarchical partitioning methods to explore the influence of topographic and forest stand structure factors on herbaceous species diversity.

Results: (1) The herbaceous Shannon-Wiener diversity index in the forest was negatively correlated with the slope aspect (P < 0.05), and the Shannon-Wiener diversity index decreased with the slope aspect (from sunny to shady slopes). The four diversity indices had no significant correlation with elevation, slope, and concavity. (2) The species richness index and Shannon-Wiener diversity index decreased with the increase in stand density and forest species richness but increased with the rise of mean DBH. The four species diversity indices were not significantly correlated with coefficient of variation of DBH (DBHcv). (3) The hierarchical partitioning method showed that environmental factors explained herbaceous species diversity as follows: stand density > DBH > DBHcv > elevation. Stand density was the main factor affecting the species diversity of herbaceous plants under the forest.

Conclusion: This study revealed the effects of different topographic factors and forest stand structure factors on the diversity of herbaceous plants in the warm temperate deciduous broad-leaved forest, and confirmed that stand density was the key factor. Our findings will contribute to the comprehensive understanding of forest biodiversity in the promotion and protection of forest ecosystem and biodiversity.

Key words: topography, forest stand structure, herbaceous plants, species diversity

Tingting Deng, Yan Wei, Siyuan Ren, Yan Zhu. Effects of topography and stand structure of warm temperate deciduous broad-leaved forest on understory herb diversity in Donglingshan, Beijing[J]. Biodiv Sci, 2023, 31(7): 22671.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2022671

https://www.biodiversity-science.net/EN/Y2023/V31/I7/22671

Figures/Tables 4

Table 1 Correlation coefficients between topography, forest stand structure and herbaceous species diversity index in a 20 ha warm temperate deciduous broad-leaved forest dynamics plot in Donglingshan

参数 Parameters	物种丰富度 Species richness	Shannon-Wiener多样性指数 Shannon-Wiener diversity index	Simpson优势度指数 Simpson dominance index
海拔 Elevation	-0.017	-0.102	-0.119	-0.130
坡度 Slope	0.042	0.043	0.075	0.017
凹凸度 Convexity	0.087	0.047	0.051	-0.028
坡向 Slope aspect	-0.148	-0.187^*	-0.153	-0.111
林分密度 Stand density	-0.280^**	-0.224^*	-0.163	0.065
平均胸径 Mean of diameter at breast height (DBH)	0.295^**	0.243^**	0.181	0.032
胸径变异系数 Coefficient of variation of DBH (DBHcv)	-0.154	-0.107	-0.07	0.021
林地物种丰富度 Forest species richness	-0.234^**	-0.180^*	-0.163	-0.032

Fig. 1 Regression fitting between topography and forest stand structure and herbaceous species diversity index in a 20 ha warm temperate deciduous broad-leaved forest dynamics plot in Donglingshan. DBHcv, Coefficient of variation of DBH. Gray represent 95% confidence interval.

Fig. 2 Redundancy analysis (RDA) biplot of topography and forest stand structure and herbaceous species diversity index in 20 ha warm temperate deciduous broad-leaved forest dynamics plot in Donglingshan. R, Species richness; H′, Shannon-Wiener diversity index; D, Simpson dominance index; E, Pielou evenness index; DBHcv, Coefficient of variation of DBH.

Fig. 3 The relative importance of individual variable of topography and forest stand structure in 20 ha warm temperate deciduous broad-leaved forest dynamics plot in Donglingshan by rdacca.hp. DBHcv, Coefficient of variation of DBH.

References 68

[1]	Ali A, Yan ER, Chen HYH, Chang SX, Zhao YT, Yang XD, Xu MS (2016) Stand structural diversity rather than species diversity enhances aboveground carbon storage in secondary subtropical forests in Eastern China. Biogeosciences, 13, 4627-4635. DOI URL
[2]	Bell G, Lechowicz MJ, Waterway MJ (2000) Environmental heterogeneity and species diversity of forest sedges. Journal of Ecology, 88, 67-87. DOI URL
[3]	Braun EL (1950) Deciduous Forests of Eastern North America. The Blakiston Company, Philadelphia, Pennsylvania.
[4]	Chazdon RL, Pearcy RW (1991) The importance of sunflecks for forest understory plants. BioScience, 41, 760-766. DOI URL
[5]	Chen X, Li YH, Zuo YF, Lin S, Chu DJ, He KN (2022) Effects of stand characteristics and soil nutrient characteristics on herbaceous diversity. Acta Botanica Boreali-Occidentalia Sinica, 42, 1396-1407. (in Chinese with English abstract)
	[陈笑, 李远航, 左亚凡, 林莎, 初鼎晋, 贺康宁 (2022) 林分特征和土壤养分对林下草本物种多样性的影响. 西北植物学报, 42, 1396-1407.]
[6]	Chmura D (2013) Impact of alien tree species Quercus rubra L. on understorey environment and flora: A study of the Silesian upland (southern Poland). Polish Journal of Ecology, 61, 431-442.
[7]	Cielo-Filho R, Gneri MA, Martins FR (2007) Position on slope, disturbance, and tree species coexistence in a seasonal semideciduous forest in SE Brazil. Plant Ecology, 190, 189-203. DOI URL
[8]	Clark JS (2010) Individuals and the variation needed for high species diversity in forest trees. Science, 327, 1129-1132. DOI PMID
[9]	Condit R (1995) Research in large, long-term tropical forest plots. Trends in Ecology & Evolution, 10, 18-22. DOI URL
[10]	Cook JE (2015) Structural effects on understory attributes in second-growth forests of northern Wisconsin, USA. Forest Ecology and Management, 347, 188-199. DOI URL
[11]	Gaston KJ (2000) Global patterns in biodiversity. Nature, 405, 220-227. DOI
[12]	Gilliam FS (2007) The ecological significance of the herbaceous layer in temperate forest ecosystems. BioScience, 57, 845-858. DOI URL
[13]	Gilliam FS (2014) The Herbaceous Layer in Forests of Eastern North America, 2nd edn. Oxford University Press, New York.
[14]	Grime JP (1973) Competitive exclusion in herbaceous vegetation. Nature, 242, 344-347. DOI
[15]	Gu HY, Li JX, Qi G, Wang SZ (2020) Species spatial distributions in a warm-temperate deciduous broad-leaved forest in China. Journal of Forestry Research, 31, 1187-1194. DOI
[16]	Hart SA, Chen HYH (2006) Understory vegetation dynamics of North American boreal forests. Critical Reviews in Plant Sciences. 25, 381-397.
[17]	Hou JH, Huang JH, Ma KP (2004) Eleven-year population growth dynamics of major species in a Quercus liaotungensis forest in the Dongling Mountains, northern China. Acta Phytoecologica Sinica, 28, 609-615. (in Chinese with English abstract)
	[侯继华, 黄建辉, 马克平 (2004) 东灵山辽东栎林主要树种种群11年动态变化. 植物生态学报, 28, 609-615.] DOI
[18]	Hu YC, Zhang XL, Han XY, Wan XL, Liang TM, Lu XJ (2022) Responses of stand growth regeneration and understory species diversity in Quercus mongolica secondary forest to stand density. Chinese Journal of Applied Ecology, 33, 727-732. (in Chinese with English abstract)
	[胡延辰, 张晓林, 韩晓义, 万小亮, 梁泰铭, 陆秀君 (2022) 蒙古栋次生林的生长更新与林下植被多样性对林分密度的响应. 应用生态学报, 33, 727-732.] DOI
[19]	Jia SH, Wang XG, Hao ZQ, Bagchi R (2022) The effects of natural enemies on herb diversity in a temperate forest depend on species traits and neighbouring tree composition. Journal of Ecology, 110, 2615-2627. DOI URL
[20]	Jiang ZH, Ma KM (2015) Environmental filtering drives herb community composition and functional trait changes across an elevational gradient. Plant Ecology and Evolution, 148, 301-310. DOI URL
[21]	Jucker T, Bouriaud O, Avacaritei D, Dănilă I, Duduman G, Valladares F, Coomes DA (2014) Competition for light and water play contrasting roles in driving diversity-productivity relationships in Iberian forests. Journal of Ecology, 102, 1202-1213. DOI URL
[22]	Lai JS, Zou Y, Zhang JL, Peres-Neto PR (2022) Generalizing hierarchical and variation partitioning in multiple regression and canonical analyses using the rdacca.hp R package. Methods in Ecology and Evolution, 13, 782-788. DOI URL
[23]	Legendre P, Mi XC, Ren HB, Ma KP, Yu MJ, Sun IF, He FL (2009) Partitioning beta diversity in a subtropical broad-leaved forest of China. Ecology, 90, 663-674. DOI PMID
[24]	Lei XD, Fu LY, Li HK, Li YT, Tang SZ (2018) Methodology and applications of site quality assessment based on potential mean annual increment. Scientia Silvae Sinicae, 54, 116-126. (in Chinese with English abstract)
	[雷相东, 符利勇, 李海奎, 李玉堂, 唐守正 (2018) 基于林分潜在生长量的立地质量评价方法与应用. 林业科学, 54, 116-126.]
[25]	Li BH, Zhang J, Yao XL, Ye J, Wang XG, Hao ZQ (2008) Seasonal dynamics and spatial distribution patterns of herbs plant diversity in broad-leaved Korean pine (Pnus koraiensis) mixed forest in Changbai Mountains. Chinese Journal of Applied Ecology, 19, 467-473. (in Chinese with English abstract)
	[李步杭, 张健, 姚晓琳, 叶吉, 王绪高, 郝占庆 (2008) 长白山阔叶红松林草本植物多样性季节动态及空间分布格局. 应用生态学报, 19, 467-473.]
[26]	Li DZ, Zang RG (2004) The research advances on the structure and function of forest canopy, as well as their temporal and spatial changes. World Forestry Research, 17, 12-16. (in Chinese with English abstract)
	[李德志, 臧润国 (2004) 森林冠层结构与功能及其时空变化研究进展. 世界林业研究, 17, 12-16.]
[27]	Li GX, Ma KM (2018) Progress in the study of elevational patterns of soil microbial diversity. Acta Ecologica Sinica, 38, 1521-1529. (in Chinese with English abstract)
	[厉桂香, 马克明 (2018) 土壤微生物多样性海拔格局研究进展. 生态学报, 38, 1521-1529.]
[28]	Linares-Palomino R, Cardona V, Hennig EI, Hensen I, Hoffmann D, Lendzion J, Soto D, Herzog SK, Kessler M (2009) Non-woody life-form contribution to vascular plant species richness in a tropical American forest. Plant Ecology, 201, 87-99. DOI URL
[29]	Liu BR (2021) Recent advances in altitudinal distribution patterns of biodiversity. Ecology and Environmental Sciences, 30, 438-444. (in Chinese with English abstract)
	[刘秉儒 (2021) 生物多样性的海拔分布格局研究及进展. 生态环境学报, 30, 438-444.] DOI
[30]	Liu GF, Liu YP, Eerdemutu, Hou ML (2021) Species diversity of understory herbaceous plants in four typical natural secondary forests in Hanshan Nature Reserve. Journal of Northwest Forestry University, 36(2), 31-37. (in Chinese with English abstract)
	[刘贵峰, 刘玉平, 额尔德木图, 侯美玲 (2021) 罕山自然保护区4种典型天然次生林林下草本植物物种多样性. 西北林学院学报, 36(2), 31-37.]
[31]	Liu HF, Li L, Sang WG (2011) Species composition and community structure of the Donglingshan forest dynamic plot in a warm temperate deciduous broad-leaved secondary forest, China. Biodiversity Science, 19, 232-242. (in Chinese with English abstract) DOI
	[刘海丰, 李亮, 桑卫国 (2011) 东灵山暖温带落叶阔叶次生林动态监测样地: 物种组成与群落结构. 生物多样性, 19, 232-242.] DOI
[32]	Liu MX, Nan XN, Zhang GJ, Li BW, Xu L, Mu RL, Li L, Yu RX (2021) Relationship between species diversity and functional diversity of plant communities on different slopes in alpine meadow. Acta Ecologica Sinica, 41, 5398-5407. (in Chinese with English abstract)
	[刘旻霞, 南笑宁, 张国娟, 李博文, 徐璐, 穆若兰, 李亮, 于瑞新 (2021) 高寒草甸不同坡向植物群落物种多样性与功能多样性的关系. 生态学报, 41, 5398-5407.]
[33]	Liu Y, Yu X, Yu Y, Hu WH, LAI JS (2023) Application of “rdacca.hp” R package in ecological data analysis: Case and progress. Chinese Journal of Plant Ecology, 47, 134-144. (in Chinese with English abstract) DOI
	[刘尧, 于馨, 于洋, 胡文浩, 赖江山 (2023) rdacca.hp包在生态学数据分析中的应用: 案例与进展. 植物生态学报, 47, 134-144.] DOI
[34]	Lutz JA, Furniss TJ, Johnson DJ, Davies SJ, Allen D, Alonso A, Anderson-Teixeira KJ, Andrade A, Baltzer J, Becker KML, Blomdahl EM, Bourg NA, Bunyavejchewin S, Burslem DFRP, Cansler CA, Cao K, Cao M, Cárdenas D, Chang LW, Chao KJ, Chao WC, Chiang JM, Chu CJ, Chuyong GB, Clay K, Condit R, Cordell S, Dattaraja HS, Duque A, Ewango CEN, Fischer GA, Fletcher C, Freund JA, Giardina C, Germain SJ, Gilbert GS, Hao ZQ, Hart T, Hau BCH, He FL, Hector A, Howe RW, Hsieh CF, Hu YH, Hubbell SP, Inman-Narahari FM, Itoh A, Janík D, Kassim AR, Kenfack D, Korte L, Král K, Larson AJ, Li YD, Lin Y, Liu SR, Lum S, Ma KP, Makana JR, Malhi Y, McMahon SM, McShea WJ, Memiaghe HR, Mi XC, Morecroft M, Musili PM, Myers JA, Novotny V, de Oliveira A, Ong P, Orwig DA, Ostertag R, Parker GG, Patankar R, Phillips RP, Reynolds G, Sack L, Song GZM, Su SH, Sukumar R, Sun IF, Suresh HS, Swanson ME, Tan S, Thomas DW, Thompson J, Uriarte M, Valencia R, Vicentini A, Vrška T, Wang XG, Weiblen GD, Wolf A, Wu SH, Xu H, Yamakura T, Yap S, Zimmerman JK (2018) Global importance of large-diameter trees. Global Ecology and Biogeography, 27, 849-864.
[35]	Ma F, Wang SZ, Feng JZ, Sang WG (2018) Spatial distribution patterns of snag and standing trees in a warm temperate deciduous broad-leaved forest in Dongling Mountain, Beijing. Acta Ecologica Sinica, 38, 5717-5725. (in Chinese with English abstract)
	[马芳, 王顺忠, 冯金朝, 桑卫国 (2018) 北京东灵山暖温带落叶阔叶林枯立木与活立木空间分布格局. 生态学报, 38, 5717-5725.]
[36]	Ma KP, Huang JH, Yu SL, Chen LZ (1995) Plant community diversity in Dongling Mountain, Beijing, China. II. Species richness, evenness and species diversities. Acta Ecologica Sinica, 15, 268-277. (in Chinese with English abstract)
	[马克平, 黄建辉, 于顺利, 陈灵芝 (1995) 北京东灵山地区植物群落多样性的研究. II. 丰富度、均匀度和物种多样性指数. 生态学报, 15, 268-277.]
[37]	Machado MA, De Almeida JEB, (2019) Spatial structure, diversity, and edaphic factors of an area of Amazonian coast vegetation in Brazil. Journal of the Torrey Botanical Society, 146, 58-68. DOI URL
[38]	McCool DK, Brown LC, Foster GR, Mutchler CK, Meyer LD (1987) Revised slope steepness factor for the universal soil loss equation. Transactions of the ASAE, 30, 1387-1396. DOI URL
[39]	Muller RN (2014) Nutrient relations of the herbaceous layer in deciduous forest ecosystems. In: The Herbaceous Layer in Forests of Eastern North America, 2nd edn (ed. Gilliam FS), pp. 13-34. Oxford University Press, New York.
[40]	Murphy SJ, Salpeter K, Comita LS (2016) Higher beta-diversity observed for herbs over woody plants is driven by stronger habitat filtering in a tropical understory. Ecology, 97, 2074-2084. DOI URL
[41]	Oksanen J, Blanchet FG, Friendly M, Kindt R, Legendre P, McGlinn D, Minchin PR, O'Hara RB, Simpson GL, Solymos P, Stevens MHH, Szoecs E, Wagner H (2020) vegan: Community Ecology Package. R packages version 2.5-7. https://CRAN.R-project.org/package=vegan/. (accessed on 2020-11-28)
[42]	Radhamoni HVN, Queenborough SA, Arietta AZA, Suresh HS, Dattaraja HS, Kumar SS, Sukumar R, Comita LS (2023) Local- and landscape-scale drivers of terrestrial herbaceous plant diversity along a tropical rainfall gradient in western Ghats, India. Journal of Ecology, 111, 1021-1036. DOI URL
[43]	Richards PW (1952) The Tropical Rain Forest:An Ecological Study. Cambridge University Press, London.
[44]	Sang WG, Su HX, Chen LZ (2002) Coupling biomass and energy in warm temperate deciduous broad-leaved oak (Quercus liaotungensis) forest ecosystem. Acta Phytoecologica Sinica, 26, 88-92. (in Chinese with English abstract)
	[桑卫国, 苏宏新, 陈灵芝 (2002) 东灵山暖温带落叶阔叶林生物量和能量密度研究. 植物生态学报, 26, 88-92.]
[45]	Shen ZH, Zhang XS, Jin YX (2000) Spatial pattern analysis and topographical interpretation of species diversity in the forests of Dalaoling in the region of the Three Gorges. Acta Botanica Sinica, 42, 620-627. (in Chinese with English abstract)
	[沈泽昊, 张新时, 金义兴 (2000) 三峡大老岭森林物种多样性的空间格局分析及其地形解释. 植物学报, 42, 620-627.]
[46]	Shu WW, Lu LH, Li H, Nong Y, He RM, Chen H, Huang B (2021) Effects of stand density on understory vegetation and soil properties of Cunninghamia lanceolata plantation. Acta Ecologica Sinica, 41, 4521-4530. (in Chinese with English abstract)
	[舒韦维, 卢立华, 李华, 农友, 何日明, 陈海, 黄彪 (2021) 林分密度对杉木人工林林下植被和土壤性质的影响. 生态学报, 41, 4521-4530.]
[47]	Spicer ME, Mellor H, Carson WP (2020) Seeing beyond the trees: A comparison of tropical and temperate plant growth forms and their vertical distribution. Ecology, 101, e02974.
[48]	Spicer ME, Radhamoni HVN, Duguid MC, Queenborough SA, Comita LS (2022) Herbaceous plant diversity in forest ecosystems: Patterns, mechanisms, and threats. Plant Ecology, 223, 117-129. DOI
[49]	Tang ZY, Fang JY (2004) A review on the elevational patterns of plant species diversity. Biodiversity Science, 12, 20-28. (in Chinese with English abstract) DOI URL
	[唐志尧, 方精云 (2004) 植物物种多样性的垂直分布格局. 生物多样性, 12, 20-28.] DOI
[50]	Thrippleton T, Bugmann H, Folini M, Snell RS (2018) Overstorey-understorey interactions intensify after drought-induced forest die-off: Long-term effects for forest structure and composition. Ecosystems, 21, 723-739. DOI URL
[51]	Tilman D (1999) The ecological consequences of changes in biodiversity: A search for general principles. Ecology, 80, 1455-1474.
[52]	Wang DP, Ji SY, Chen FP (2001) A review on the species diversity of plant community. Chinese Journal of Ecology, 20(4), 55-60. (in Chinese with English abstract)
	[汪殿蓓, 暨淑仪, 陈飞鹏 (2001) 植物群落物种多样性研究综述. 生态学杂志, 20(4), 55-60.]
[53]	Wang YH, Li SF, Lang XD, Huang XB, Liu WD, Xu CH, Su JR (2020) Effects of topographic heterogeneity on species diversity in a monsoon ever green broad-leaved forest in Pu'er, Yunnan, China. Chinese Journal of Plant Ecology, 44, 1015-1027. (in Chinese with English abstract) DOI URL
	[王艳红, 李帅锋, 郎学东, 黄小波, 刘万德, 徐崇华, 苏建荣 (2020) 地形异质性对云南普洱季风常绿阔叶林物种多样性的影响. 植物生态学报, 44, 1015-1027.]
[54]	Warren RJ, Bradford MA (2011) The shape of things to come:Woodland herb niche contraction begins during recruitment in mesic forest microhabitat. Proceedings of the Royal Society B: Biological Sciences, 278, 1390-1398.
[55]	Wayman RB, North M (2007) Initial response of a mixed-conifer understory plant community to burning and thinning restoration treatments. Forest Ecology and Management, 239, 32-44. DOI URL
[56]	Wulf M, Naaf T (2009) Herb layer response to broadleaf tree species with different leaf litter quality and canopy structure in temperate forests. Journal of Vegetation Science, 20, 517-526. DOI URL
[57]	Xie JY, Chen LZ (1994) Species diversity characteristics of deciduous forests in the warm temperate zone of North China. Acta Ecologica Sinica, 14, 337-344. (in Chinese with English abstract)
	[谢晋阳, 陈灵芝 (1994) 暖温带落叶阔叶林的物种多样性特征. 生态学报, 14, 337-344.]
[58]	Xue R, Yang Q, Miao FH, Wang XZ, Shen YY (2018) Slope aspect influences plant biomass, soil properties and microbial composition in alpine meadow on the Qinghai-Tibetan Plateau. Journal of Soil Science and Plant Nutrition, 18, 1-12.
[59]	Yang X, Yao ZL, Wang B, Wen HD, Deng Y, Cao M, Zhang ZM, Tan ZH, Lin LX (2023) Driving effects of forest stand structure of a subtropical evergreen broad-leaved forest on species composition variation: From local to regional scales. Biodiversity Science, 31, 22139. (in Chinese with English abstract) DOI
	[杨欣, 姚志良, 王彬, 温韩东, 邓云, 曹敏, 张志明, 谭正洪, 林露湘 (2023) 亚热带常绿阔叶林林分结构对物种组成变异的驱动作用: 从局域到区域尺度. 生物多样性, 31, 22139.] DOI
[60]	Zhang L, Qi S, Zhou P, Wu BC, Zhang D, Cui RR, Huang X, Ma N (2022) Analysis of influencing factors on the understory herbaceous plant diversity of Platycladus orientalis forest in Beijing mountainous areas. Acta Agrestia Sinica, 30, 2199-2206. (in Chinese with English abstract)
	[张林, 齐实, 周飘, 伍冰晨, 张岱, 崔冉冉, 黄宪, 马宁 (2022) 北京山区侧柏林下草本植物多样性的影响因素分析. 草地学报, 30, 2199-2206.] DOI
[61]	Zhang LH, Qi JQ, Li TT, Yu SY, Zhang XY, Zhang R, Hao JF (2019) Effects of stand density on understory plant diversity and biomass in a Pinus massoniana plantation in Wenfeng Mountain, Xinjin County. Acta Ecologica Sinica, 39, 5709-5717. (in Chinese with English abstract)
	[张柳桦, 齐锦秋, 李婷婷, 鱼舜尧, 张潇月, 张荣, 郝建锋 (2019) 林分密度对新津文峰山马尾松人工林林下物种多样性和生物量的影响. 生态学报, 39, 5709-5717.]
[62]	Zhang LX, Zhang F, Shangguan TL (2000) Vegetation diversity of Luya Mountains. Chinese Biodiversity, 8, 361-369. (in Chinese with English abstract)
	[张丽霞, 张峰, 上官铁梁 (2000) 芦芽山植物群落的多样性研究. 生物多样性, 8, 361-369.]
[63]	Zhang SX, Qin RM, Yang XY, Wen J, Xu MH (2020) Patterns of species diversity in herbaceous communities at different altitude gradients and their relationships with environmental factors in Lüliang Mountains in Shanxi Province, China. Guihaia, 40, 1860-1868. (in Chinese with English abstract)
	[张世雄, 秦瑞敏, 杨晓艳, 温静, 徐满厚 (2020) 山西吕梁山草本群落物种多样性的海拔梯度格局及与环境因子的关系. 广西植物, 40, 1860-1868.]
[64]	Zhang W, Liu WC, Xu MP, Deng J, Han XH, Yang GH, Feng YZ, Ren GX (2019) Response of forest growth to C : N : P stoichiometry in plants and soils during Robinia pseudoacacia afforestation on the Loess Plateau, China. Geoderma, 337, 280-289. DOI
[65]	Zhang YX, Liu TR, Guo JP, Tan ZJ, Dong W, Wang HH (2021) Changes in the understory diversity of secondary Pinus tabulaeformis forests are the result of stand density and soil properties. Global Ecology and Conservation, 28, e01628.
[66]	Zhao ZH, Hui GY (2020) Advances in structural diversity of stand structure. Scientia Silvae Sinicae, 56, 143-152. (in Chinese with English abstract)
	[赵中华, 惠刚盈 (2020) 林分结构多样性研究进展. 林业科学, 56, 143-152.]
[67]	Zhu Q, Ai XR, Wu ML, Huang X, Wang J, Peng ZL (2019) Species diversity pattern and environmental explanation of evergreen deciduous broad-leaved mixed forest in Qizimei Mountains. Acta Botanica Boreali-Occidentalia Sinica, 39, 1491-1502. (in Chinese with English abstract)
	[朱强, 艾训濡, 吴漫玲, 黄小, 王进, 彭宗林 (2019) 七姊妹山常绿落叶阔叶混交林物种多样性格局及其环境解释. 西北植物学报, 39, 1491-1502.]
[68]	Zhu YJ, Yang XH, Shi ZJ, Liu YS, Zhang X (2018) The influence of stand factors on species diversity of herb layer in Zhangbei poplar plantations. Chinese Journal of Ecology, 37, 2869-2879. (in Chinese with English abstract)
	[朱媛君, 杨晓晖, 时忠杰, 刘艳书, 张晓 (2018) 林分因子对张北杨树人工林林下草本层物种多样性的影响. 生态学杂志, 37, 2869-2879.]