喀斯特与非喀斯特森林乔木叶性状及其相关性网络的差异

doi:10.17521/cjpe.2022.0469

摘要/Abstract

摘要：

喀斯特地区岩石裸露、土壤浅薄、持水能力差。对比分析喀斯特和非喀斯特森林树种叶性状有利于了解叶片对喀斯特生境的生理生态适应。前期比较研究集中在叶经济学性状, 对叶水力学(抗旱)和机械抗性(防御)性状关注较少。该研究测定热带-亚热带地区典型喀斯特和非喀斯特森林共101种乔木的叶形态解剖、机械抗性和水力学性状, 比较两个植物类群叶性状以及性状网络的差异。结果发现: (1)与非喀斯特森林乔木相比, 喀斯特森林乔木叶撕裂力(F_t)较大、最大导水率(K_{leaf_max})较高, 膨压丧失点(Ψ_tlp)和气孔安全边界均较低。(2)喀斯特森林乔木叶性状网络的平均路径长度和直径较短, 边缘密度较大, 表明叶性状之间的关联程度更高。(3)喀斯特森林乔木叶性状网络的关键性状为比叶质量(LMA)和机械抗性, 而非喀斯特森林则为叶厚度(LT)和叶密度。喀斯特森林乔木LMA与Ψ_tlp负相关, 与F_t正相关, 即增加叶构建成本可同时提高机械抗性和耐失水能力; 非喀斯特森林乔木无此相关关系。(4)喀斯特森林乔木K_{leaf_max}与叶抗栓塞能力(耐旱性)之间权衡, 它们与叶形态解剖和机械抗性均不相关; 非喀斯特森林乔木无水力学权衡关系, K_{leaf_max}与LT和叶密度显著相关。该研究进一步揭示了与非喀斯特森林相比, 喀斯特森林乔木倾向于采取异水策略, 且叶性状之间密切协同。

关键词: 形态, 解剖, 水力学, 机械阻力, 热带-亚热带森林, 喀斯特

Abstract:

Aims This study aims to clarify the differences in ecological strategies between karst and non-karst forest tree species, in terms of leaf morphology and anatomy, hydraulics, and mechanical resistance.

Methods A total of 101 tree species were selected from typical karst and non-karst forests in tropical-subtropical regions. We measured: (1) leaf morphological and anatomical traits including leaf thickness (LT), leaf density (LD), vein density and leaf mass per area (LMA); (2) leaf mechanical traits including force to punch and force to tear (F_t); and (3) leaf hydraulic traits including maximum hydraulic conductance (K_{leaf_max}), cavitation resistance (P50_leaf), turgor loss point (Ψ_tlp), and stomatal safety margin (HSM_tlp). We compared the differences in leaf traits between karst and non-karst forest tree species, and analyzed their traits correlation networks.

Important findings (1) Compared to non-karst forest tree species, on average the karst tree species had greater F_t, higher K_{leaf_max}, lower (more negative) Ψ_tlp and HSM_tlp. (2) Leaf trait network of karst forest tree species showed shorter average path length and diameter and lower edge density than non-karst forest tree species, indicating that traits combinations were closer in karst forests. (3) Mechanical traits and LMA showed high connectedness in the trait networks of karst forest tree species, LT and LD showed high connectedness in those of non-karst tree species. In karst forest tree species, LMA was positively correlated with F_t and negatively correlated with Ψ_tlp, indicating that increasing leaf carbon investment can simultaneously enhance meachnical resistance and drought tolerance. However, no such correlations were found in non-karst forest tree species. (4) Across karst forests tree species, we found a significant tradeoff between K_{leaf_max} and P50_leaf, both of which were not related with leaf mechanical resistance, and morphological and anatomical traits. By contrast, there was no hydraulic tradeoff in non-karst forest tree species, and K_{leaf_max} was significantly correlated with LT and LD. This study further reveals that compared to non-karst forest tree species, karst forest tree species tend to exhibit isohydraulic strategy and show closer coordination among leaf traits.

Key words: morphology, anatomy, hydraulics, mechanical resistance, tropical-subtropical forest, karst

万春燕, 余俊瑞, 朱师丹. 喀斯特与非喀斯特森林乔木叶性状及其相关性网络的差异. 植物生态学报, 2023, 47(10): 1386-1397. DOI: 10.17521/cjpe.2022.0469

WAN Chun-Yan, YU Jun-Rui, ZHU Shi-Dan. Differences in leaf traits and trait correlation networks between karst and non-karst forest tree species. Chinese Journal of Plant Ecology, 2023, 47(10): 1386-1397. DOI: 10.17521/cjpe.2022.0469

导出引用管理器 EndNote|Ris|BibTeX

链接本文: https://www.plant-ecology.com/CN/10.17521/cjpe.2022.0469

https://www.plant-ecology.com/CN/Y2023/V47/I10/1386

图/表 4

参考文献 58

[1]	Bartlett MK, Scoffoni C, Sack L (2012). The determinants of leaf turgor loss point and prediction of drought tolerance of species and biomes: a global meta-analysis. Ecology Letters, 15, 393-405. DOI PMID
[2]	Blackman CJ, Brodribb TJ, Jordan GJ (2010). Leaf hydraulic vulnerability is related to conduit dimensions and drought resistance across a diverse range of woody angiosperms. New Phytologist, 188, 1113-1123. DOI PMID
[3]	Blumenthal DM, Mueller KE, Kray JA, Ocheltree TW, Augustine DJ, Wilcox KR (2020). Traits link drought resistance with herbivore defence and plant economics in semi-arid grasslands: the central roles of phenology and leaf dry matter content. Journal of Ecology, 108, 2336-2351. DOI URL
[4]	Chen YJ, Cao KF, Schnitzer SA, Fan ZX, Zhang JL, Bongers F (2015). Water-use advantage for lianas over trees in tropical seasonal forests. New Phytologist, 205, 128-136. DOI URL
[5]	Chen ZC, Wang L, Dai YX, Wan XC, Liu SR (2017). Phenology-dependent variation in the non-structural carbohydrates of broadleaf evergreen species plays an important role in determining tolerance to defoliation (or herbivory). Scientific Reports, 7, 10125. DOI: 10.1038/s41598-017-09757-2.
[6]	Deng XB, Tang JW (2010). Chinese Ecosystem Localization Observation and Research Dataset—Volume on Forest Ecosystems: Xishuangbanna Yunnan (1998-2006). China Agriculture Press, Beijing.
	[邓晓保, 唐建维 (2010). 中国生态系统定位观测与研究数据集——森林生态系统卷: 云南西双版纳站(1998-2006). 中国农业出版社, 北京.]
[7]	Deng Y, Ke J, Wu S, Jiang GH, Jiang ZC, Zhu AJ (2020). Responses of plant water uptake to groundwater depth in limestone outcrops. Journal of Hydrology, 590, 125377. DOI: 10.1016/j.jhydrol.2020.125377.
[8]	Ding YL, Nie YP, Chen HS, Wang KL, Querejeta JI (2021). Water uptake depth is coordinated with leaf water potential, water-use efficiency and drought vulnerability in karst vegetation. New Phytologist, 229, 1339-1353. DOI URL
[9]	Feng X, Ackerly DD, Dawson TE, Manzoni S, Mclaughlin B, Skelton RP, Vico G, Weitz AP, Thompson SE (2019). Beyond isohydricity: the role of environmental variability in determining plant drought responses. Plant, Cell & Environment, 42, 1104-1111.
[10]	Flores-Moreno H, Fazayeli F, Banerjee A, Datta A, Kattge J, Butler EE, Atkin OK, Wythers K, Chen M, Anand M, Bahn M, Byun C, Cornelissen JHC, Craine J, Gonzalez- Melo A, et al. (2019). Robustness of trait connections across environmental gradients and growth forms. Global Ecology and Biogeography, 28, 1806-1826. DOI
[11]	Fu PL, Zhu SD, Zhang JL, Finnegan PM, Jiang YJ, Lin H, Fan ZX, Cao KF (2019). The contrasting leaf functional traits between a karst forest and a nearby non-karst forest in south-west China. Functional Plant Biology, 46, 907-915. DOI URL
[12]	Han L, Zhao CZ, Xu T, Feng W, Duan BB (2017). Relationships between leaf thickness and vein traits of Achnatherum splendens under different soil moisture conditions in a flood plain wetland, Heihe River, China. Chinese Journal of Plant Ecology, 41, 529-538. DOI URL
	[韩玲, 赵成章, 徐婷, 冯威, 段贝贝 (2017). 不同土壤水分条件下洪泛平原湿地芨芨草叶片厚度与叶脉性状的关系. 植物生态学报, 41, 529-538.] DOI
[13]	He NP, Li Y, Liu CC, Xu L, Li MX, Zhang JH, He JS, Tang ZY, Han XG, Ye Q, Xiao CW, Yu Q, Liu SR, Sun W, Niu SL, et al. (2020). Plant trait networks: improved resolution of the dimensionality of adaptation. Trends in Ecology & Evolution, 35, 908-918. DOI URL
[14]	Hothorn T, Bretz F, Westfall P (2008). Simultaneous inference in general parametric models. Biometrische Zeitschrift, 50, 346-363.
[15]	Hua L, He PC, Goldstein G, Liu H, Yin D, Zhu SD, Ye Q (2020). Linking vein properties to leaf biomechanics across 58 woody species from a subtropical forest. Plant Biology, 22, 212-220. DOI PMID
[16]	Huang QH, Cai YL (2009). Mapping karst rock in southwest China. Mountain Research and Development, 29, 14-20. DOI URL
[17]	Huang YQ, Li XK, Zhang ZF, He CX, Zhao P, You YM, Mo L (2011). Seasonal changes in Cyclobalanopsis glauca transpiration and canopy stomatal conductance and their dependence on subterranean water and climatic factors in rocky karst terrain. Journal of Hydrology, 402, 135-143. DOI URL
[18]	Jin Y, Wang CK (2016). Leaf hydraulic traits and their trade- offs for nine Chinese temperate tree species with different wood properties. Chinese Journal of Plant Ecology, 40, 702-710. DOI URL
	[金鹰, 王传宽 (2016). 九种不同材性的温带树种叶水力性状及其权衡关系. 植物生态学报, 40, 702-710.] DOI
[19]	John GP, Scoffoni C, Buckley TN, Villar R, Poorter H, Sack L (2017). The anatomical and compositional basis of leaf mass per area. Ecology Letters, 20, 412-425. DOI PMID
[20]	Kleyer M, Trinogga J, Cebrián-Piqueras MA, Trenkamp A, Fløjgaard C, Ejrnæs R, Bouma TJ, Minden V, Maier M, Mantilla-Contreras J, Albach DC, Blasius B (2019). Trait correlation network analysis identifies biomass allocation traits and stem specific length as hub traits in herbaceous perennial plants. Journal of Ecology, 107, 829-842. DOI URL
[21]	Kumagai T, Porporato A (2012). Strategies of a Bornean tropical rainforest water use as a function of rainfall regime: isohydric or anisohydric? Plant, Cell & Environment, 35, 61-71.
[22]	Lamont BB, Groom PK, Williams M, He TH (2015). LMA, density and thickness: recognizing different leaf shapes and correcting for their nonlaminarity. New Phytologist, 207, 942-947. DOI PMID
[23]	Li L, McCormack ML, Ma CG, Kong DL, Zhang Q, Chen XY, Zeng H, Niinemets Ü, Guo DL (2015). Leaf economics and hydraulic traits are decoupled in five species-rich tropical-subtropical forests. Ecology Letters, 18, 899-906. DOI PMID
[24]	Liu CC, Li Y, He NP (2022). Differential adaptation of lianas and trees in wet and dry forests revealed by trait correlation networks. Ecological Indicators, 135, 108564. DOI: 10.1016/j.ecolind.2022.108564.
[25]	Liu MX, Xu XL, Wang DB, Sun AY, Wang KL (2016). Karst catchments exhibited higher degradation stress from climate change than the non-karst catchments in southwest China: an ecohydrological perspective. Journal of Hydrology, 535, 173-180.
[26]	Marini L, Ayres MP, Battisti A, Faccoli M (2012). Climate affects severity and altitudinal distribution of outbreaks in an eruptive bark beetle. Climatic Change, 115, 327-341. DOI URL
[27]	Markesteijn L, Poorter L, Bongers F, Paz H, Sack L (2011). Hydraulics and life history of tropical dry forest tree species: coordination of species’ drought and shade tolerance. New Phytologist, 191, 480-495. DOI PMID
[28]	Martin-StPaul N, Delzon S, Cochard H (2017). Plant resistance to drought depends on timely stomatal closure. Ecology Letters, 20, 1437-1447. DOI PMID
[29]	McDowell N, Pockman WT, Allen CD, Breshears DD, Cobb N, Kolb T, Plaut J, Sperry J, West A, Williams DG, Yepez EA (2008). Mechanisms of plant survival and mortality during drought: Why do some plants survive while others succumb to drought? New Phytologist, 178, 719-739. DOI PMID
[30]	Méndez-Alonzo R, Ewers FW, Jacobsen AL, Pratt RB, Scoffoni C, Bartlett MK, Sack L (2019). Covariation between leaf hydraulics and biomechanics is driven by leaf density in Mediterranean shrubs. Trees, 33, 507-519. DOI
[31]	Nardini A, Pedà G, Rocca NL (2012). Trade-offs between leaf hydraulic capacity and drought vulnerability: morpho- anatomical bases, carbon costs and ecological consequences. New Phytologist, 196, 788-798. DOI PMID
[32]	Ogburn RM, Edwards EJ (2012). Quantifying succulence: a rapid, physiologically meaningful metric of plant water storage. Plant, Cell & Environment, 35, 1533-1542.
[33]	Oliveira RS, Eller CB, Barros FdV, Hirota M, Brum M, Bittencourt P (2021). Linking plant hydraulics and the fast-slow continuum to understand resilience to drought in tropical ecosystems. New Phytologist, 230, 904-923. DOI PMID
[34]	Onoda Y, Westoby M, Adler PB, Choong AMF, Clissold FJ, Cornelissen JHC, Díaz S, Dominy NJ, Elgart A, Enrico L, Fine PVA, Howard JJ, Jalili A, Kitajima K, Kurokawa H, et al. (2011). Global patterns of leaf mechanical properties. Ecology Letters, 14, 301-312. DOI PMID
[35]	Poorter H, Lambers H, Evans JR (2014). Trait correlation networks: a whole-plant perspective on the recently criticized leaf economic spectrum. New Phytologist, 201, 378-382. DOI PMID
[36]	Powers JS, Vargas GG, Brodribb TJ, Schwartz NB, Pérez-Aviles D, Smith-Martin CM, Becknell JM, Aureli F, Blanco R, Calderón-Morales E, Calvo-Alvarado JC, Calvo-Obando AJ, Chavarría MM, Carvajal-Vanegas D, Jiménez-Rodríguez CD, et al. (2020). A catastrophic tropical drought kills hydraulically vulnerable tree species. Global Change Biology, 26, 3122-3133. DOI PMID
[37]	Reich PB, Oleksyn J (2004). Global patterns of plant leaf N and P in relation to temperature and latitude. Proceedings of the National Academy of Sciences of the United States of America, 101, 11001-11006.
[38]	Sack L, Cowan PD, Jaikumar N, Holbrook NM (2003). The ‘hydrology’ of leaves: co-ordination of structure and function in temperate woody species. Plant, Cell & Environment, 26, 1343-1356.
[39]	Sack L, Frole K (2006). Leaf structural diversity is related to hydraulic capacity in tropical rain forest trees. Ecology, 87, 483-491. PMID
[40]	Sack L, Scoffoni C (2013). Leaf venation: structure, function, development, evolution, ecology and applications in the past, present and future. New Phytologist, 198, 983-1000. DOI PMID
[41]	Sade N, Gebremedhin A, Moshelion M (2012). Risk-taking plants. Plant Signaling & Behavior, 7, 767-770.
[42]	Sanchez-Martinez P, Martínez-Vilalta J, Dexter KG, Segovia RA, Mencuccini M (2020). Adaptation and coordinated evolution of plant hydraulic traits. Ecology Letters, 23, 1599-1610. DOI URL
[43]	Scoffoni C, Rawls M, Mckown A, Cochard H, Sack L (2011). Decline of leaf hydraulic conductance with dehydration: relationship to leaf size and venation architecture. Plant Physiology, 156, 832-843. DOI PMID
[44]	Scoffoni C, Vuong C, Diep S, Cochard H, Sack L (2014). Leaf shrinkage with dehydration: coordination with hydraulic vulnerability and drought tolerance. Plant Physiology, 164, 1772-1788. DOI PMID
[45]	Shipley B, Lechowicz MJ, Wright I, Reich PB (2006). Fundamental trade-offs generating the worldwide leaf economics spectrum. Ecology, 87, 535-541. PMID
[46]	Song TQ (2015). Plants and the Environment in Karst Areas of Southwest China. Science Press, Beijing.
	[宋同清 (2015). 西南喀斯特植物与环境. 科学出版社, 北京.]
[47]	Song TQ, Peng WX, Zeng FP, Wang KL, Qin WG, Tan WN, Liu L, Du H, Lu SY (2010). Spatial pattern of forest communities and environmental interpretation in Mulun national nature reserve, karst cluster-peak depression region. Chinese Journal of Plant Ecology, 34, 298-308.
	[宋同清, 彭晚霞, 曾馥平, 王克林, 覃文更, 谭卫宁, 刘璐, 杜虎, 鹿士杨 (2010). 木论喀斯特峰丛洼地森林群落空间格局及环境解释. 植物生态学报, 34, 298-308.] DOI
[48]	Tang SB, Liu JF, Lambers H, Zhang LL, Liu ZF, Lin YT, Kuang YW (2021). Increase in leaf organic acids to enhance adaptability of dominant plant species in karst habitats. Ecology and Evolution, 11, 10277-10289. DOI PMID
[49]	Wei Y, Liu H, He PC, Liu XR, Ye Q (2022). Coordination between leaf construction cost and mechanical resistance of dominant woody species in subtropical forests at different successional stages. Journal of Tropical and Subtropical Botany, 30, 483-491.
	[韦伊, 刘慧, 贺鹏程, 刘小容, 叶清 (2022). 南亚热带不同演替阶段森林优势树种叶片构建成本与机械抗性的协同关系. 热带亚热带植物学报, 30, 483-491.]
[50]	Wright IJ, Reich PB, Westoby M, Ackerly DD, Baruch Z, Bongers F, Cavender-Bares J, Chapin T, Cornelissen JHC, Diemer M, Flexas J, Garnier E, Groom PK, Gulias J, Hikosaka K, et al. (2004). The worldwide leaf economics spectrum. Nature, 428, 821-827. DOI
[51]	Yan CL, Ni MY, Cao KF, Zhu SD (2020). Leaf hydraulic safety margin and safety-efficiency trade-off across angiosperm woody species. Biology Letters, 16, 20200456. DOI: 10.1098/rsbl.2020.0456.
[52]	Yao GQ, Nie ZF, Turner NC, Li FM, Gao TP, Fang XW, Scoffoni C (2021). Combined high leaf hydraulic safety and efficiency provides drought tolerance in Caragana species adapted to low mean annual precipitation. New Phytologist, 229, 230-244. DOI URL
[53]	Yuan DX (1992). Karst in southwest China and its comparison with karst in north China. Quaternary Science, 12, 352-361.
	[袁道先 (1992). 中国西南部的岩溶及其与华北岩溶的对比. 第四纪研究, 12, 352-361.]
[54]	Zhang QM (2011). Chinese Ecosystem Localization Observation and Research Dataset—Volume on Forest Ecosystems: Dinghu, Guangdong (1998-2008). China Agriculture Press, Beijing.
	[张倩媚 (2011). 中国生态系统定位观测与研究数据集——森林生态系统卷: 广东鼎湖山站(1998-2008). 中国农业出版社, 北京.]
[55]	Zhang QW, Zhu SD, Jansen S, Cao KF (2021). Topography strongly affects drought stress and xylem embolism re- sistance in woody plants from a karst forest in Southwest China. Functional Ecology, 35, 566-577. DOI URL
[56]	Zhang YB, Zhou CY, Lv WQ, Dai LH, Tang JG, Zhou SQ, Huang LH, Li AD, Zhang JL (2019). Comparative study of the stoichiometric characteristics of karst and non-karst forests in Guizhou, China. Journal of Forestry Research, 30, 799-806. DOI
[57]	Zhu H (2007). The karst ecosystem of southern China and its biodiversity. Tropical Forestry, 35, 44-47.
	[朱华 (2007). 中国南方石灰岩(喀斯特)生态系统及生物多样性特征. 热带林业, 35, 44-47.]
[58]	Zhu SD, Chen YJ, Fu PL, Cao KF (2017). Different hydraulic traits of woody plants from tropical forests with contrasting soil water availability. Tree Physiology, 37, 1469-1477. DOI URL

类别 Type	性状 Trait	缩写 Code	单位 Unit	定义 Definition
形态解剖 Morphology & anatomy	比叶质量 Leaf mass per area	LMA	g·m^-2	叶面积与干质量的比值, 经济学核心性状, 与碳投资成本有关(Wright et al., 2004) Defined as leaf dry mass per unit area. A central leaf economic trait that related to carbon investment (Wright et al., 2004)
	叶片密度 Leaf density	LD	mg·cm^-3	叶干质量与体积的比值, 反映叶组织的致密程度, 与碳投资成本有关(Lamont et al., 2015) Defined as the ratio of dry mass to volume. It reflects the density of leaf tissue, a central leaf economic trait that related to carbon investment (Lamont et al., 2015)
	叶脉密度 Vein density	VD	mm·mm^-2	单位面积三级叶脉以上的叶脉长度之和, 与水分运输有关(Lamont et al., 2015) Defined as the sum of the vein length per unit leaf area. It relates to water transport capacity (Lamont et al., 2015)
	叶片厚度 Leaf thickness	LT	μm	叶各组织厚度之和, 与抗性和光合能力以及碳投资成本相关(Lamont et al., 2015) Defined as the sum of the thicknesses of leaf tissues. It relates to resistance, photosynthetic capacity, and carbon investment cost (Lamont et al., 2015)
机械抗性 Biomechanics	穿刺力 Leaf force to punch	F_p	kN·m^-1	穿透单位周长的叶片所需要的力, 反映机械抗性(Onoda et al., 2011) Defined as the force to penetrate a leaf. It reflects mechanical resistance (Onoda et al., 2011)
机械抗性 Biomechanics	撕裂力 Leaf force to tear	F_t	kN·m^-1	撕裂单位宽度的叶片所需要的力, 反映机械抗性(Onoda et al., 2011) Defined as the force to tear a leaf. It reflects mechanical resistance (Onoda et al., 2011)
水力学 Hydraulics	抗栓塞能力 Leaf cavitation resistance	P50_leaf	MPa	叶片导水率损失50%时的水势值, 反映叶栓塞抗性和水力失败的阈值(Sack & Frole, 2006) Defined as the water potential inducing 50% loss of leaf hydraulic conductance. It reflects embolic resistance and the threshold of hydraulic failure (Sack & Frole, 2006)
	叶片最大导水率 Maximum leaf hydraulic conductance	K_{leaf_max}	mmol·m^-2·s^-1· MPa^-1	反映叶水分运输能力, 与气体交换参数相关(Sack & Frole, 2006) It reflects the water transport capacity of leaves and relates to gas exchange (Sack & Frole, 2006)
	膨压丧失点 Leaf water potential at turgor loss point	Ψ_tlp	MPa	膨压为0时的水势, 反映耐失水能力, 与气孔关闭有关(Bartlett et al., 2012) Defined as leaf water potential at which turgor pressure is zero. It estimates to desiccation resistance and relates to stomatal closure (Bartlett et al., 2012)
	气孔安全边界 Stomatal safety margin	HSM_tlp	MPa	Ψ_tlp与P50_leaf的差值, 反映气孔调节策略(Powers et al., 2020) Defined as the difference between Ψ_tlp and P50_leaf. It reflects the stomatal regulation strategy (Powers et al., 2020)

类别 Type	性状 Trait	缩写 Code	单位 Unit	定义 Definition
形态解剖 Morphology & anatomy	比叶质量 Leaf mass per area	LMA	g·m^-2	叶面积与干质量的比值, 经济学核心性状, 与碳投资成本有关(Wright et al., 2004) Defined as leaf dry mass per unit area. A central leaf economic trait that related to carbon investment (Wright et al., 2004)
	叶片密度 Leaf density	LD	mg·cm^-3	叶干质量与体积的比值, 反映叶组织的致密程度, 与碳投资成本有关(Lamont et al., 2015) Defined as the ratio of dry mass to volume. It reflects the density of leaf tissue, a central leaf economic trait that related to carbon investment (Lamont et al., 2015)
	叶脉密度 Vein density	VD	mm·mm^-2	单位面积三级叶脉以上的叶脉长度之和, 与水分运输有关(Lamont et al., 2015) Defined as the sum of the vein length per unit leaf area. It relates to water transport capacity (Lamont et al., 2015)
	叶片厚度 Leaf thickness	LT	μm	叶各组织厚度之和, 与抗性和光合能力以及碳投资成本相关(Lamont et al., 2015) Defined as the sum of the thicknesses of leaf tissues. It relates to resistance, photosynthetic capacity, and carbon investment cost (Lamont et al., 2015)
机械抗性 Biomechanics	穿刺力 Leaf force to punch	F_p	kN·m^-1	穿透单位周长的叶片所需要的力, 反映机械抗性(Onoda et al., 2011) Defined as the force to penetrate a leaf. It reflects mechanical resistance (Onoda et al., 2011)
机械抗性 Biomechanics	撕裂力 Leaf force to tear	F_t	kN·m^-1	撕裂单位宽度的叶片所需要的力, 反映机械抗性(Onoda et al., 2011) Defined as the force to tear a leaf. It reflects mechanical resistance (Onoda et al., 2011)
水力学 Hydraulics	抗栓塞能力 Leaf cavitation resistance	P50_leaf	MPa	叶片导水率损失50%时的水势值, 反映叶栓塞抗性和水力失败的阈值(Sack & Frole, 2006) Defined as the water potential inducing 50% loss of leaf hydraulic conductance. It reflects embolic resistance and the threshold of hydraulic failure (Sack & Frole, 2006)
	叶片最大导水率 Maximum leaf hydraulic conductance	K_{leaf_max}	mmol·m^-2·s^-1· MPa^-1	反映叶水分运输能力, 与气体交换参数相关(Sack & Frole, 2006) It reflects the water transport capacity of leaves and relates to gas exchange (Sack & Frole, 2006)
	膨压丧失点 Leaf water potential at turgor loss point	Ψ_tlp	MPa	膨压为0时的水势, 反映耐失水能力, 与气孔关闭有关(Bartlett et al., 2012) Defined as leaf water potential at which turgor pressure is zero. It estimates to desiccation resistance and relates to stomatal closure (Bartlett et al., 2012)
	气孔安全边界 Stomatal safety margin	HSM_tlp	MPa	Ψ_tlp与P50_leaf的差值, 反映气孔调节策略(Powers et al., 2020) Defined as the difference between Ψ_tlp and P50_leaf. It reflects the stomatal regulation strategy (Powers et al., 2020)