Studies on forest ecosystem physiology: marginal water-use efficiency of a tropical, seasonal, evergreen forest in Thailand

Abstract

Marginal water-use efficiency plays a critical role in plant carbon–water coupling relationships. We investigated the ecosystem marginal water-use efficiency (λ) of a tropical seasonal evergreen forest to (1) determine the general pattern of λ across time, (2) compare different models for calculating λ, and (3) address how λ varies with soil water content during different seasons. There was a U-shaped diurnal pattern in λ, which was higher in the early morning and late afternoon. At other times of the day, λ was lower and remained constant. Ecosystem λ was higher in the wet season than in the dry season. All three models successfully captured the diurnal and seasonal patterns of λ but differed in the calculated absolute values. The idea that λ is constant on a subdaily scale was partly supported by our study, while a constant λ was only true when data from the early morning and late afternoon were not included. The λ increases with soil water content on a seasonal scale, possibly because early morning λ remained low in dry conditions when the soil water content was low.

Keywords

Canopy conductance / Stomatal optimization / Soil moisture / Photosynthesis model

References

[1] Baldocchi D. Measuring fluxes of trace gases and energy between ecosystems and the atmosphere—the state and future of the eddy covariance method. Glob Change Biol, 2014, 20: 3600-3609.

[2] Beerling DJ. The emerald planet: how plants changed Earth’s history, 2007, Oxford: Oxford University Press 9 34

[3] Cowan IR. Stomatal behaviour and environment. Adv Ecol Res, 1977, 4: 117-228.

[4] Cowan I Lange OL Regulation of water use in relation to carbon gain in higher plants. Physiological plant ecology II. Water relations and carbon assimilation, 1982, Berlin: Springer 589 614

[5] Cowan IR, Farquhar GD. Jennings DH. Stomatal function in relation to leaf metabolism and environment. Integration of activity in the high plant, 1977, London: Cambridge University Press 471 505

[6] Darwin F. Observations on stomata. Proc R Soc Lond, 1898, 63: 413-417.

[7] Edwards D, Davies KL, Axe L. A vascular conducting strand in the early land plant cooksonia. Nature, 1992, 357: 683-685.

[8] Farquhar GD, O’Leary MH, Berry JA. On the relationship between carbon isotope discrimination and the intercellular carbon dioxide concentration in leaves. Aust J Plant Physiol, 1982, 9(2): 281-292.

[9] Farquhar GD, Sharkey TD. Stomatal conductance and photosynthesis. Ann Rev Plant Physiol, 1982, 33: 317-345.

[10] Fan JZ, Wang D, Hu YL, Jing PP, Wang PP, Chen JQ. Optimal stomatal behavior theory for simulating stomatal conductance. Chin J Plant Ecol, 2016, 40: 631-642.

[11] Fick A. Uber diffusion. Annalen der Physik und Chemie, 1855, 94: 59-96.

[12] Gao Y, Xia J, Chen Y, Zhao Y, Kong Q, Lang Y. Effects of extreme soil water stress on photosynthetic efficiency and water consumption characteristics of Tamarix chinensisin China’s Yellow River Delta. J For Res, 2017, 28: 491-501.

[13] Givnish TJ. Givnish TJ. Optimal stomatal conductance, allocation of energy between leaves and roots, and the marginal cost of transpiration. On the economy of plant from and function, vol 115, no 4, 1986, New York: Bull. Torrey Bot. Club 319

[14] Givnish TJ, Vermeij GJ. Sizes and shapes of liane leaves. Am Nat, 1976, 110: 743-778.

[15] Katul G, Manzoni S, Palmroth S, Oren R. Stomatal optimization theory to describe the effects of atmospheric CO₂ on leaf photosynthesis and transpiration. Ann Bot, 2010, 105: 431-442.

[16] Konrad W, Roth-Nebelsick A, Grein M. Modelling of stomatal density in response to atmospheric CO₂. J Therm Biol, 2008, 253: 638-658.

[17] Lasslop G, Reichstein M, Detto M, Richardson AD, Baldocchi DD. Comment on vickers et al.: self-correlation between assimilation and respiration resulting from flux partitioning of eddy-covariance CO₂, fluxes. Agr Forest Meteorol, 2010, 150(2): 312-314.

[18] Lin YS, Medlyn BE, Duursma RA Optimal stomatal behavior around the world. Nat Clim Change, 2015, 5: 459-464.

[19] Lloyd J, Farquhar GD. ¹³C discrimination during Co₂ assimilation by the terrestrial biosphere. Oecologia, 1994, 99(3/4): 201-215.

[20] Mäkelä A, Berninger F, Hari P. Optimal control of gas exchange during drought: theoretical analysis. Ann Bot, 1996, 77: 461-468.

[21] Manzoni S, Vico G, Katul G Optimizing stomatal conductance for maximum carbon gain under water stress: a meta-analysis across plant functional types and climates. Funct Ecol, 2011, 25: 456-467.

[22] Medlyn BE, Duursma RA, Eamus D Reconciling the optimal and empirical approaches to modeling stomatal conductance. Glob Change Biol, 2011, 17: 2134-2144.

[23] Medlyn BE, Duursma RA, De Kauwe MG, Prentice IC. The optimal stomatal response to atmospheric CO₂ concentration: alternative solutions, alternative interpretations. Agric For Meteorol, 2013, 182–183: 200-203.

[24] Mondal D, Percival DB. Wavelet variance analysis for gappy time series. Ann Inst Stat Math, 2010, 62: 943-966.

[25] Monteith JL. Evaporation and environment. Symp Soc Exp Biol, 1965, 19(19): 205-234.

[26] Tan ZH, Zhang YP, Yu GR Spatial and temporal dynamics of CO2 concentration and its causes in Xishuangbanna tropical seasonal rain forest, China. Chin J Plant Ecol, 2008, 32: 555-567.

[27] Thomas DS, Eamus D, Bell D. Optimization theory of stomatal behaviour: I. A critical evaluation of five methods of calculation. J Exp Bot, 1999, 50: 385-392.

[28] Vico G, Manzoni S, Palmroth S, Weih M, Katul G. A perspective on optimal leaf stomatal conductance under CO₂ and light co-limitations. Agric For Meteorol, 2013, 182–183: 191-199.

[29] Willmer C, Fricker M (1996) Stomata, 2nd edn. Springer, New York, pp 92–106, 126–177

[30] Xia J, Zhang S, Guo J, Rong Q, Zhang G. Critical effects of gas exchange parameters in Tamarix chinensis Lour on soil water and its relevant environmental factors on a shell ridge island in China’s Yellow River Delta. Ecol Eng, 2017, 76: 36-46.

[31] Xia J, Zhao X, Ren J, Lang Y, Qu F, Xu H. Photosynthetic and water physiological characteristics of Tamarix chiensis under different groundwater sanilty conditions. Environ Exp Bot, 2017, 138: 173-183.

[32] Xia J, Zhao Z, Sun J, Liu J, Zhao Y. Response of stem sap flow and leaf photosynthesis in Tamarix chinensis to soil mositure in the Yellow River Delta, China. Photosynthetica, 2017, 55: 368-377.

[33] Yamakura T. An empirical approach to the analysis of forest stratification: I. Proposed graphical method derived by using an empirical distribution function. J Plant Res, 1987, 100: 109-128.

[34] Zhou S, Duursma RA, Medlyn BE, Kelly JW, Prentice IC. How should we model plant responses to drought? An analysis of stomatal and non-stomatal responses to water stress. Agric For Meteorol, 2013, 182: 204-214.

[35] Zhou S, Medlyn B, Sabaté S, Sperlich D, Prentice IC. Short-term water stress impacts on stomatal, mesophyll and biochemical limitations to photosynthesis differ consistently among tree species from contrasting climates. Tree Physiol, 2014, 34: 1035-1046.