Abstract
Although the growth limitation hypothesis (GLH) is the most accepted physiological explanation for alpine treeline formation, the debate about its formation mechanisms still remains controversial due to contradictory findings from different studies. The functional difference between trees and alpine low-stature shrubs may hold answers, as shrubs grow well at higher elevations. We investigated carbon (C) storage in deciduous treeline species Betula ermanii (Erman’s birch) and two dominant shrubs (deciduous Vaccinium uliginosum and evergreen Rhododendron aureum), which naturally grow next to each other at the treeline ecotone on Changbai Mountain, Northeast China. We determined growth and non-structural carbohydrate (NSC) concentrations in organs with increasing elevation at the mid-growing season. Results showed that in the treeline ecotone soil temperature was lower than tree canopy air temperature due to unobvious aerodynamic decoupling near the ground. Species growth consistently decreased with increasing elevation, while NSC concentrations responded differently to elevation between trees and shrubs. An elevational increase and decrease in NSC were observed in leaves and woody organs, respectively, of B. ermanii. NSC concentrations in each organ significantly increased with increasing elevation for R. aureum but decreased for V. uliginosum. At the treeline, shrubs had higher values than B. ermanii in NSC, ratios of soluble sugars to starch in leaves, and leaf mass per area. Organ dependence of NSC with increasing elevation in Betula trees provided partial support for the GLH, while R. aureum and V. uliginosum provided strong support for the GLH and carbon limitation hypothesis, respectively. These imply that alpine shrubs may have evolved to maintain more advantageous C balance and functional features than did trees as an adaptation to higher-elevation climates.
Similar content being viewed by others
References
Alvarez-Uria P, Körner C (2007) Low temperature limits of root growth in deciduous and evergreen temperate tree species. Funct Ecol 21:211–218
Dang HS, Zhang KR, Zhang QF, Xu YM (2015) Temporal variations of mobile carbohydrates in Abies fargesii at the upper tree limits. Plant Biol 17:106–113
Dawes MA, Hattenschwiler S, Bebi P, Hagedorn F, Handa IT, Körner C, Rixen C (2011) Species-specific tree growth responses to 9 years of CO2 enrichment at the alpine treeline. J Ecol 99:383–394
Fajardo A (2016) Wood density is a poor predictor of competitive ability among individuals of the same species. For Ecol Manag 372:217–225
Fajardo A, Piper FI (2014) An experimental approach to explain the southern Andes elevational treeline. Am J Bot 101:788–795
Fajardo A, Piper FI (2017) An assessment of carbon and nutrient limitations in the formation of the southern Andes tree line. J Ecol 105:517–527
Fajardo A, Piper FI, Cavieres LA (2011) Distinguishing local from global climate influences in the variation of carbon status with altitude in a tree line species. Glob Ecol Biogeogr 20:307–318
Fajardo A, Piper FI, Pfund L, Körner C, Hoch G (2012) Variation of mobile carbon reserves in trees at the alpine treeline ecotone is under environmental control. New Phytol 195:794–802
Fajardo A, Piper FI, Hoch G (2013) Similar variation in carbon storage between deciduous and evergreen treeline species across elevational gradients. Ann Bot 112:623–631
Genet M, Li MC, Luo TX, Fourcaud T, Clement-Vidal A, Stokes A (2011) Linking carbon supply to root cell-wall chemistry and mechanics at high altitudes in Abies georgei. Ann Bot 107:311–320
Handa IT, Körner C, Hattenschwiler S (2005) A test of the tree-line carbon limitation hypothesis by in situ CO2 enrichment and defoliation. Ecology 86:1288–1300
Hartmann H, Trumbore S (2016) Understanding the roles of nonstructural carbohydrates in forest trees - from what we can measure to what we want to know. New Phytol 211:386–403
Hoch G, Körner C (2003) The carbon charging of pines at the climatic treeline: a global comparison. Oecologia 135:10–21
Hoch G, Körner C (2009) Growth and carbon relations of tree line forming conifers at constant vs. variable low temperatures. J Ecol 97:57–66
Hoch G, Körner C (2012) Global patterns of mobile carbon stores in trees at the high-elevation tree line. Glob Ecol Biogeogr 21:861–871
Hoch G, Popp M, Körner C (2002) Altitudinal increase of mobile carbon pools in Pinus cembra suggests sink limitation of growth at the Swiss treeline. Oikos 98:361–374
Hultine KR, Marshall JD (2000) Altitude trends in conifer leaf morphology and stable carbon isotope composition. Oecologia 123:32–40
James J, Grace J, Hoad S (1994) Growth and photosynthesis of Pinus sylvestris at its altitudinal limit in Scotland. J Ecol 82:297–306
Jobbágy E, Jackson R (2000) Global controls of forest line elevation in the northern and southern hemispheres. Glob Ecol Biogeogr 9:253–268
Körner C (1998) A re-assessment of high elevation treeline positions and their explanation. Oecologia 115:445–459
Körner C (2003) Alpine plant life: functional plant ecology of high mountain ecosystems. Springer, Berlin Heidelberg, New York
Körner C (2007) Climatic treelines: conventions, global patterns, causes. Erdkunde 61:316–324
Körner C (2008) Winter crop growth at low temperature may hold the answer for alpine treeline formation. Plant Ecol Divers 1:3–11
Körner C (2012a) Alpine treelines: functional ecology of the global high elevation tree limits. Springer Science & Business Media, New York
Körner C (2012b) Treelines will be understood once the functional difference between a tree and a shrub is. Ambio 41:197–206
Körner C, Paulsen J (2004) A world-wide study of high altitude treeline temperatures. J Biogeogr 31:713–732
Kozlowski TT (1992) Carbohydrate sources and sinks in woody-plants. Bot Rev 58:107–222
Lemoine R, La Camera S, Atanassova R, Dédaldéchamp F, Allario T, Pourtau N, Bonnemain J-L, Laloi M, Coutos-Thévenot P, Maurousset L (2013) Source-to-sink transport of sugar and regulation by environmental factors. Front Plant Sci 4:272
Lenz A, Vitasse Y, Hoch G, Korner C (2014) Growth and carbon relations of temperate deciduous tree species at their upper elevation range limit. J Ecol 102:1537–1548
Li MH, Yang J (2004) Effects of microsite on growth of Pinus cembra in the subalpine zone of the Austrian Alps. Ann For Sci 61:319–325
Li MH, Hoch G, Korner C (2001) Spatial variability of mobile carbohydrates within Pinus cembra trees at the alpine treeline. Phyton-Ann Rei Botanicae 41:203–213
Li MH, Xiao WF, Shi PL, Wang SG, Zhong YD, Liu XL, Wang XD, Cai XH, Shi ZM (2008a) Nitrogen and carbon source-sink relationships in trees at the Himalayan treelines compared with lower elevations. Plant, Cell Environ 31:1377–1387
Li MH, Xiao WF, Wang SG, Cheng GW, Cherubini P, Cai XH, Liu XL, Wang XD, Zhu WZ (2008b) Mobile carbohydrates in Himalayan treeline trees I. Evidence for carbon gain limitation but not for growth limitation. Tree Physiol 28:1287–1296
Liu Q-J, Xu Q-Q, Zhang G-C (2009) Impact of alpine snowpacks on primary productivity in Rhododendron aureum community in Changbai Mountain, China. Acta Ecol Sinica 29:4035–4044
Martínez-Vilalta J, Sala A, Asensio D, Galiano LA, Hoch GN, Palacio S, Piper FI, Lloret F (2016) Dynamics of non-structural carbohydrates in terrestrial plants: a global synthesis. Ecol Monogr 86:495–516
McIntire EJB, Piper FI, Fajardo A (2016) Wind exposure and light exposure, more than elevation-related temperature, limit treeline seedling abundance on three continents. J Ecol 104:1379–1390
Piper FI, Vinegla B, Linares JC, Camarero JJ, Cavieres LA, Fajardo A (2016) Mediterranean and temperate treelines are controlled by different environmental drivers. J Ecol 104:691–702
Poorter H, Niinemets Ü, Poorter L, Wright IJ, Villar R (2009) Causes and consequences of variation in leaf mass per area (LMA): a meta-analysis. New Phytol 182:565–588
Rossi S, Deslauriers A, Anfodillo T, Carraro V (2007) Evidence of threshold temperatures for xylogenesis in conifers at high altitudes. Oecologia 152:1–12
Sakai A., Larcher W. 1987. Frost survival of plants: responses and adaptation to freezing stress. Berlin, etc.[Ecological Studies, vol. 62.] Springer-Verlag 321 pp. Chaps. incl.: freezing process in plants
Sala A, Woodruff DR, Meinzer FC (2012) Carbon dynamics in trees: feast or famine? Tree Physiol 32:764–775
Shi P, Koerner C, Hoch G (2006) End of season carbon supply status of woody species near the treeline in western China. Basic Appl Ecol 7:370–377
Shi P, Körner C, Hoch G (2008) A test of the growth-limitation theory for alpine tree line formation in evergreen and deciduous taxa of the eastern Himalayas. Funct Ecol 22:213–220
Solfjeld I, Johnsen O (2006) The influence of root-zone temperature on growth of Betula pendula Roth. Trees-Struct Funct 20:320–328
Stevens GC, Fox JF (1991) The causes of treeline. Ann Rev Ecol System 22:177–191
Sveinbjörnsson B, Smith M, Traustason T, Ruess RW, Sullivan PF (2010) Variation in carbohydrate source-sink relations of forest and treeline white spruce in southern, interior and northern Alaska. Oecologia 163:833–843
Tranquillini W (1979) Physiological ecology of the alpine timberline: tree existence at high altitude with special reference to the European Alps. Springer, Berlin
Wang Q-W, Qi L, Zhou W, Liu C-G, Yu D, Dai L (2018) Carbon dynamics in the deciduous broadleaf tree Erman’s birch (Betula ermanii) at the subalpine treeline on Changbai Mountain, Northeast China. Am J Bot. https://doi.org/10.1002/ajb2.1006
Wardle P (1993) Causes of alpine timberline: a review of the hypotheses. In: Alden J.N., Mastrantonio J.L., Ødum S. (eds) Forest development in cold climates. NATO ASI Series (Series A: Life Sciences), vol 244. Springer, Boston, MA
Wiley E, Helliker B (2012) A re-evaluation of carbon storage in trees lends greater support for carbon limitation to growth. New Phytol 195:285–289
Xu WD, Lin CQ (1981) Preliminary study of relations between vertical distribution of vegetation and thermal climate in Changbai Mountain. Res For Ecosyst 2:88–95
Yu DP, Wang GG, Dai LM, Wang QL (2007) Dendroclimatic analysis of Betula ermanii forests at their upper limit of distribution in Changbai Mountain, Northeast China. For Ecol Manag 240:105–113
Yu D, Wang Q, Liu J, Zhou W, Qi L, Wang X, Zhou L, Dai L (2014) Formation mechanisms of the alpine Erman’s birch (Betula ermanii) treeline on Changbai Mountain in Northeast China. Trees - Struct Funct 28:935–947
Zhu WZ, Cao M, Wang SG, Xiao WF, Li MH (2012) Seasonal dynamics of mobile carbon supply in Quercus aquifolioides at the upper elevational limit. PLoS ONE 7:e34213
Acknowledgments
We thank Ms. Jie Tian, Juan Jia, Hong Ding, Jiaqing Liu, Yuewei Tong, and Guanhua Dai for technical assistance in the field, Ms. Xiaoyu Wang for valuable comments, and the Office of the Changbai Mountain Natural Reserve for field investigation permission. This work was supported by the National Natural Science Foundation of China [Grant Numbers 41701052, 41571197]; Open Fund of Changbai Mountain Academy of Science; Special Research Project of Institute of Applied Ecology, CAS [Grant Number Y5YZX151YD]; and Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, CAS [Grant Number LFEM2016–05]. We thank two anonymous reviewers for valuable comments that improved earlier versions of the manuscript.
Author information
Authors and Affiliations
Corresponding authors
Additional information
Communicated by Enright.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Wang, QW., Liu, CG., Zhou, W. et al. Mobile carbon supply in trees and shrubs at the alpine treeline ecotone. Plant Ecol 219, 467–479 (2018). https://doi.org/10.1007/s11258-018-0809-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11258-018-0809-3