Underestimation of mountain species richness on the Qingzang Plateau when using base zone surveys: a case study of mountain vertical vegetation spectrum in the Rongbu River watershed of Mount Qomolangma

doi:10.17521/cjpe.2024.0236

Abstract

Abstract:

Aims Species richness patterns along altitudinal gradients in mountain ecosystems have been a central theme in ecological research. While past studies often investigated species richness on individual mountains, regional-scale analyses have typically relied on samples collected along roadsides or foothills, potentially neglecting the crucial aspect of vertical zonation in mountain biodiversity.
Methods Eight mountains along the Rongbu River with varying base altitudes (ranging from 3 785 m to 5 155 m) were selected for the study. Employing transect and quadrat methods, species richness was comprehensively surveyed across the vertical zones of these mountains.
Important findings (1) A total of 81 plant species were recorded in this survey, including species such as Elymus nutans, Poa tibetica, Arenaria bryophylla, and Astragalus strictus, all of which were documented across all eight mountains in the basin. (2) On a watershed scale, species richness per unit area (1 m²) followed a unimodal curve with respect to altitude. However, on individual mountain ranges, the distribution patterns of species richness per unit area along the altitude gradient varied, showing U-shaped distributions, positive correlations, or no significant relationships. (3) Overall, the cumulative species richness in the lower parts of the mountains was lower than in the middle and upper parts. Additionally, the species richness per unit area was higher on the shady slopes of the mountains compared to the sunny slopes. This study revealed a significant disparity between species richness in the base zone of the mountains and the overall species richness of the entire mountain. This finding indicates that plant surveys conducted solely along roadsides or at the mountain base significantly underestimate the species richness of the entire mountain by 13.5% to 54.8%. Therefore, it is imperative to pay particular attention to the distribution patterns of species richness across mountain spatial scales and their key influencing factors in mountain ecosystems, especially on the Qingzang Plateau.

Key words: Rongbu River watershed, mountain species richness, vertical vegetation spectrum, spatial patterns, Mount Qomolangma

LI Bo-Wen, ZHOU Yang, LÜ Jing-Ya, A Wang, CHEN Lan-Ying, LIU Shi-Zhang, WU Jing, LÜ Wang-Wang, SUN Jian-Ping, JIA Yue-Feng, ZHAO Kuang, WANG Shi-Ping. Underestimation of mountain species richness on the Qingzang Plateau when using base zone surveys: a case study of mountain vertical vegetation spectrum in the Rongbu River watershed of Mount Qomolangma[J]. Chin J Plant Ecol, 2025, 49(3): 404-414.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2024.0236

https://www.plant-ecology.com/EN/Y2025/V49/I3/404

Figures/Tables 8

Fig. 1 Distribution of the Rongbu River watershed and surveyed mountains (A) and schematic diagram of the surveyed mountain regions (B). M01-M08 represent eight mountain slopes investigated in the Rongbu River watershed, numbered sequentially from upstream to downstream. A1, A2 and A3 represent three altitude zones classified based on altitude. E1, E2 and E3 represent three survey scenarios defined for each mountain slope.

Table 1 Detailed information in all mountains surveyed in the Rongbu River watershed

山体编号 Mountain No.	山体基带海拔 Mountain base altitude (m)	调查海拔上限 Upper altitude (m)	样线长度 Transect length (m)	垂直落差 Altitude difference (m)	年降水量 Annual Precipitation (mm)	年平均气温 Mean annual air temperature (℃)	坡向 Slope	坐标 Coordinate
M01	5 155	5 274	700	119	1 101	-6.4	西南 Southwest	86.89° E, 28.08° N
M02	5 150	5 281	300	131	685	-6.2	东北 Northeast	86.85° E, 28.13° N
M03	4 619	5 041	1 000	422	403	0.9	西北 Northwest	86.85° E, 28.30° N
M04	4 695	5 029	400	334	451	1.7	西南 Southwest	86.85° E, 28.33° N
M05	4 327	4 755	600	428	330	3.1	东北 Northeast	86.94° E, 28.37° N
M06	4 365	4 652	500	287	342	3.5	西南 Southwest	86.97° E, 28.37° N
M07	3 785	4 123	600	338	734	2.2	东北 Northeast	87.35° E, 28.32° N
M08	3 810	4 313	500	503	734	2.2	西南 Southwest	87.36° E, 28.31° N

Table 2 Information on different mountains categorized by altitude ranges in the Rongbu River watershed

山体编号 Mountain ID	海拔区间 Altitude range	物种丰富度 Species richness	海拔下限 Lower limit of altitude (m)	海拔上限 Upper limit of altitude (m)
M01	A1	32	5 155	5 195
	A2	13	5 195	5 235
	A3	15	5 235	5 275
M02	A1	16	5 150	5 194
	A2	19	5 194	5 238
	A3	24	5 238	5 281
M03	A1	30	4 619	4 760
	A2	31	4 760	4 901
	A3	36	4 901	5 041
M04	A1	19	4 695	4 807
	A2	24	4 807	4 918
	A3	24	4 918	5 029
M05	A1	24	4 327	4 470
	A2	29	4 470	4 613
	A3	33	4 613	4 755
M06	A1	20	4 365	4 461
	A2	35	4 461	4 567
	A3	28	4 567	4 652
M07	A1	14	3 785	3 898
	A2	20	3 898	4 011
	A3	23	4 011	4 123
M08	A1	10	3 810	3 978
	A2	13	3 978	4 146
	A3	11	4 146	4 313

Fig. 2 Variation in cumulative species richness of each mountain along the altitude gradient in the Rongbu River watershed. M01-M08 denote eight independent mountains surveyed from upstream to downstream of the Rongbu River, details see Table 2.

Fig. 3 Variation in cumulative species richness with mountain survey altitude range at the watershed scale of Rongbu River (aggregate results of eight mountains). E1 represents surveys limited to the lower part of the mountain, E2 represents surveys in both the middle and lower parts of the mountain, and E3 represents surveys covering the entire mountain.

Fig. 4 Comparison of species richness per unit area on shady and sunny slopes across different base zone altitude gradients in Rongbu River watershed. BA1-BA4 represent four different base zone altitude gradients from the upstream to the downstream of the Rongbu River (5 153, 4 657, 4 346 and 3 798 m, respectively). * indicates a significant difference in species richness per unit area between the shady and sunny slopes (p < 0.05).

Fig. 5 Relationship between species richness across altitude gradients on individual mountains in Rongbu River watershed. A-H represent Mountains M01-M08, mountain details see Table 2. Grey points indicate species richness surveyed in each plot. R2 and p values of the fits are annotated in the top of each subplot. Solid black line represents a significant fitted curve (p < 0.05).

Fig. 6 Relationship between cumulative species richness in the base zone and cumulative species richness in the middle and upper parts of mountains within the Rongbu River watershed. A2, A3, and All represent regions within the middle part and upper part of the mountain, and the entire mountain, respectively.

References 36

[1]	Barry RG (2008) Mountain Weather and Climate. 3rd ed. Cambridge University Press, New York.
[2]	Cheng C, He N, Li M, Xu L, Cai W, Li X, Zhao W, Li C, Sun OJ (2023). Plant species richness on the Tibetan Plateau: patterns and determinants. Ecography, 2023, e06265. DOI: 10.1111/ecog.06265.
[3]	Chi XL, Tang ZY (2011). Effects of area, temperature and geometric constraints on elevational patterns of species richness: a case study in the Mountain Taibai, Qinling Mountains, China, Chinese Journal of Plant Ecology, 35, 362-370.
	[池秀莲, 唐志尧 (2011). 面积、温度及分布区限制对物种丰富度海拔格局的影响: 以秦岭太白山为例. 植物生态学报, 35, 362-370.] DOI
[4]	Ding WN, Ree RH, Spicer RA, Xing YW (2020). Ancient orogenic and monsoon-driven assembly of the world’s richest temperate alpine flora. Science, 369, 578-581.
[5]	Dorji T, Moe SR, Klein JA, Totland Ø (2014). Plant species richness, evenness, and composition along environmental gradients in an alpine meadow grazing ecosystem in central Tibet, China. Arctic, Antarctic, and Alpine Research, 46, 308-326.
[6]	Fang JY, Kanzaki M, Wang XP, Yoda K, Sun SZ, Shimota K (2004). Community structure of alpine sparse vegetation and effects of micro-topography in Pushila, Everest-Choyu region, Tibet, China. Biodiversity Science, 12, 190-199. DOI
	[方精云, 神崎护, 王襄平, 依田恭二, 孙世洲, 下田胜久 (2004). 西藏珠峰-卓奥友峰普士拉地区高山稀疏植被的群落特征及小地形的影响. 生物多样性, 12, 190-199.] DOI
[7]	Gaston KJ (2000). Global patterns in biodiversity. Nature, 405, 220-227.
[8]	He JS, Chen WL (1997). A review of gradient changes in species in species diversity of land plant communities. Acta Ecologica Sinica, 17, 91-98.
	[贺金生, 陈伟烈 (1997). 陆地植物群落物种多样性的梯度变化特征. 生态学报, 17, 91-98.]
[9]	Körner C (2000). Why are there global gradients in species richness? Mountains might hold the answer. Trends in Ecology & Evolution, 15, 513-514.
[10]	Körner C (2007). The use of ‘altitude’ in ecological research. Trends in Ecology & Evolution, 22, 569-574.
[11]	La D, Zhang YJ, Liu J, Cui LL, Pang YZ (2016). Spatial distribution patterns and environmental interpretation of plant species richness in the Lhasa Valley, Tibet. Acta Prataculturae Sinica, 25, 202-211. DOI
	[拉多, 张燕杰, 刘杰, 崔玲玲, 庞有智 (2016) 拉萨河谷植物物种丰富度空间分布格局及其环境解释. 草业学报, 25, 202-211.] DOI
[12]	La Q, Zhaxi CR, Zhu WD, Xu M, Zhong Y (2014). Plant species-richness and association with environmental factors in the riparian zone of the Yarlung Zangbo River of Tibet, China. Biodiversity Science, 22, 337-347. DOI
	[拉琼, 扎西次仁, 朱卫东, 许敏, 钟扬 (2014). 雅鲁藏布江河岸植物物种丰富度分布格局及其环境解释. 生物多样性, 22, 337-347.] DOI
[13]	Li WH, Ganjurjav H, Cao XJ, Yan YL, Li Y, Luo WR, Hu GZ, Danjiu LB, He SC, Gao QZ (2017). Effects of altitude on plant productivity and species diversity in alpine meadows of northern Tibet. Acta Prataculturae Sinica, 26, 200-207.
	[栗文瀚, 干珠扎布, 曹旭娟, 闫玉龙, 李钰, 罗文蓉, 胡国铮, 旦久罗布, 何世丞, 高清竹 (2017). 海拔梯度对藏北高寒草地生产力和物种多样性的影响. 草业学报, 26, 200-207.] DOI
[14]	Liu KM, Zheng Z, Gong DJ (2017). Elevational patterns of species richness and their underlying mechanism. Chinese Journal of Ecology, 36, 541-554.
	[刘开明, 郑智, 龚大洁 (2017). 物种丰富度的垂直分布格局及其形成机制. 生态学杂志, 36, 541-554.]
[15]	Liu Z, Li Q, Chen DD, Zhai WT, Zhao L, Xu SX, Zhao XQ (2015). Patterns of plant species diversity along an altitudinal gradient and its effect on above-ground biomass in alpine meadows in Qinghai-Tibet Plateau. Biodiversity Science, 23, 451-462. DOI
	[刘哲, 李奇, 陈懂懂, 翟文婷, 赵亮, 徐世晓, 赵新全 (2015). 青藏高原高寒草甸物种多样性的海拔梯度分布格局及对地上生物量的影响. 生物多样性, 23, 451-462.] DOI
[16]	Meng FD, Wang CS, Zhang ZH, Chang XF, Wang SP (2013). Comparative study of monitoring methods about plant diversity and aboveground biomass of alpine grasslands in the Tibetan Plateau. Acat Botanica Boreali-Occidentalia Sinica, 33, 1923-1929.
	[孟凡栋, 王常顺, 张振华, 常小峰, 汪诗平 (2013). 西藏高原高寒草地群落植物多样性和地上生物量监测方法的比较研究. 西北植物学报, 33, 1923-1929.]
[17]	Meng FD, Wang CS, Zhu XX, Cui SJ, Wang Q, Zhou Y, Wang SP (2016). Sampling methods about species richness and aboveground biomass of Potentilla fruticosa shrub meadow on Tibetan Plateau. Chinese Journal of Ecology, 35, 3435-3442.
	[孟凡栋, 王常顺, 朱小雪, 崔树娟, 王奇, 周阳, 汪诗平 (2016). 西藏高原金露梅灌丛草甸物种丰富度和生物量取样方法探讨. 生态学杂志, 35, 3435-3442.]
[18]	Moeslund JE, Arge L, Bøcher PK, Dalgaard T, Svenning JC (2013). Topography as a driver of local terrestrial vascular plant diversity patterns. Nordic Journal of Botany, 31, 129-144.
[19]	Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GA, Kent J (2000). Biodiversity hotspots for conservation priorities. Nature, 403, 853-858.
[20]	Niu YJ, Zhou JW, Yang SW, Wang GZ, Liu L, Hua LM (2017). Quantitative apportionment of slope aspect and altitude to soil moisture and temperature and plant distribution on alpine meadow. Chinese Journal of Applied Ecology, 28, 1489-1497.
	[牛钰杰, 周建伟, 杨思维, 王贵珍, 刘丽, 花立民 (2017). 坡向和海拔对高寒草甸山体土壤水热和植物分布格局的定量分解. 应用生态学报, 28, 1489-1497.] DOI
[21]	Nogués-Bravo D, Araújo MB, Romdal T, Rahbek C (2008). Scale effects and human impact on the elevational species richness gradients. Nature, 453, 216-219.
[22]	O’Brien EM (2006). Biological relativity to water-energy dynamics. Journal of Biogeography, 33, 1868-1888.
[23]	Palmer MW, White PS (1994). Scale dependence and the species-area relationship. The American Naturalist, 144, 717-740.
[24]	Perring F (1959). Topographical gradients of chalk grassland. Journal of Ecology, 47, 447-481.
[25]	Rahbek C (1995). The elevational gradient of species richness: a uniform pattern? Ecography, 18, 200-205.
[26]	Rahbek C (2005). The role of spatial scale and the perception of large-scale species-richness patterns. Ecology Letters, 8, 224-239.
[27]	Rahbek C, Borregaard MK, Colwell RK, Dalsgaard B, Holt BG, Morueta-Holme N, Nogues-Bravo D, Whittaker RJ, Fjeldså J (2019). Humboldt’s Enigma: What causes global patterns of mountain biodiversity? Science, 365, 1108-1113.
[28]	Shimono A, Zhou HK, Shen HH, Hirota M, Ohtsuka T, Tang YH (2010). Patterns of plant diversity at high altitudes on the Qinghai-Tibetan Plateau. Journal of Plant Ecology, 3, 1-7. DOI
[29]	Stevens GC (1992). The elevational gradient in altitudinal range: an extension of Rapoport’s latitudinal rule to altitude. The American Naturalist, 140, 893-911.
[30]	Sundqvist MK, Sanders NJ, Wardle DA (2013). Community and ecosystem responses to elevational gradients: processes, mechanisms, and insights for global change. Annual Review of Ecology, Evolution, and Systematics, 44, 261-280.
[31]	Wang CT, Long RJ, Wang QJ, Ding LM, Wang MP (2007). Effects of altitude on plant-species diversity and productivity in an alpine meadow, Qinghai-Tibetan Plateau. Australian Journal of Botany, 55, 110-117.
[32]	Wang ZH, Chen AP, Piao SL, Fang JY (2004). Pattern of species richness along an altitudinal gradient on Gaoligong Mountains, Southwest China. Biodiversity Science, 12, 82-88. DOI
	[王志恒, 陈安平, 朴世龙, 方精云 (2004). 高黎贡山种子植物物种丰富度沿海拔梯度的变化. 生物多样性, 12, 82-88.] DOI
[33]	Whittaker RJ, Willis KJ, Field R (2001). Scale and species richness: towards a general, hierarchical theory of species diversity. Journal of Biogeography, 28, 453-470.
[34]	Yang K, Jiang YX, Tang WJ, He J, Shao CK, Zhou X, Lu H, Chen YY, Li X, Shi JC (2023). A high-resolution near-surface meteorological forcing dataset for the Third Pole region (TPMFD, 1979-2022). National Tibetan Plateau/Third Pole Environment Data Center. DOI: 10.11888/Atmos.tpdc.300398.
	[阳坤, 姜尧志, 唐文君, 何杰, 邵长坤, 周旭, 卢麾, 陈莹莹, 李新, 施建成 (2023). 第三极地区长时间序列高分辨率地面气象要素驱动数据集(TPMFD, 1979-2022). 国家青藏高原数据中心. DOI: 10.11888/Atmos.tpdc.300398.]
[35]	Yao SC, Wang JS, Ding LB, Bao XT, Li C, Wang T, Liu WJ, Li YY (2018). Quantitative classification and ordination of grassland communities in Lhasa River Valley. Acta Ecologica Sinica, 38, 4779-4788.
	[姚帅臣, 王景升, 丁陆彬, 包小婷, 李超, 王彤, 刘文婧, 李妍妍 (2018). 拉萨河谷草地群落的数量分类与排序. 生态学报, 38, 4779-4788.]
[36]	Zhang XL, Dong SK, Guo XD, Han YH, Li HM, Feng J, Wang C, Liu QR (2015). Comparison of different sampling techniques for alpine grassland plant diversity on Qinghai-Tibet Plateau. Chinese Journal of Ecology, 34, 3568-3574.
	[张晓蕾, 董世魁, 郭贤达, 韩雨晖, 李灏漫, 冯憬, 王琛, 刘全儒 (2015). 青藏高原高寒草地植物多样性调查方法的比较. 生态学杂志, 34, 3568-3574.]