Assessing temporal variation of primary and ecosystem production in two Mediterranean forests using a modified 3-PG model
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Forest ecosystem carbon uptake is heavily affected by increasing drought in the Mediterranean region.
The objectives of this study were to assess the capacity of a modified 3-PG model to capture temporal variation in gross primary productivity (GPP), and ecosystem net carbon uptake (NEE) in two Mediterranean forest types.
The model was upgraded from a monthly (3-PG) to a daily time step (3-PGday), and a soil water balance routine was included to better represent soil water availability. The model was evaluated against seasonal GPP and NEE dynamics from eddy covariance measurements.
Simulated and measured soil water content values were congruent throughout the study period for both forest types. 3-PGday effectively described the following: GPP and NEE seasonal patterns; the transition of forest ecosystems from carbon sink to carbon source; however, the model overestimated diurnal ecosystem respiration values and failed to predict ecosystem respiration peaks.
The model served as a rather effective tool to represent seasonal variation in gross primary productivity, and ecosystem net carbon uptake under Mediterranean drought-prone conditions. However, its semi-empirical nature and the simplicity inherent in the original model formulation are obstacles preventing the model working well for short-term daily predictions.
KeywordsCarbon balance Forest Ecosystem Mediterranean Drought Model
The research was supported by a grant from the MIUR-FISR CarboItaly Project and, in part, by the MIUR-PRIN project-N. 20085FL4E4_002. Angelo Nolè acknowledges a STMS COST-fellowship (FP0603) and thanks Anniki Makela (University of Helsinki) for useful discussion and advices. We thank two anonymous referees and the associate editor, Barry Gardiner, for their constructive comments on the manuscript.
- Campbell GS (1985) Soil physics with BASIC—transport models for soil-plant systems. Developments in Soil Science 14. Elsevier, New YorkGoogle Scholar
- Coops NC, Waring RH, Landsberg JJ (1998) Assessing forest productivity in Australia and New Zealand using a physiologically-based model driven with averaged monthly weather data and satellite-derived estimates of canopy photosynthetic capacity. Forest Ecol Manag 104:113–127. doi: 10.1016/S0378-1127(97)00248-X CrossRefGoogle Scholar
- Duursma RA, Kolari P, Perämäki M, Nikinmaa E, Hari P, Delzon S, Loustau D, Ilvesniemi H, Pumpanen J, Mäkelä A (2008) Predicting the decline in daily maximum transpiration rate of two pine stands during drought based on constant minimum leaf water potential and plant hydraulic conductance. Tree Physiol 28:265–276. doi: 10.1093/treephys/28.2.265 PubMedCrossRefGoogle Scholar
- IPCC (2007) Summary for policymakers. In: Parry ML, Canziani OF, Palutikof JP, van der Linden PJ, Hanson CE (eds) Climate Change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, pp 7–22Google Scholar
- Jarvis P, Rey A, Petsikos C, Wingate L, Rayment M, Pereira J, Banza J, David J, Miglietta F, Borghetti M, Manca G, Valentini R (2007) Drying and wetting of soils stimulates decomposition and carbon dioxide emission: the “Birch effect”. Tree Physiol 27:929–940. doi: 10.1093/treephys/27.7.929 PubMedCrossRefGoogle Scholar
- Makela A, Pulkkinen M, Kolari P, Lagergren F, Berbigier P, Lindroth A, Loustau D, Nikinmaa E, Vesala T, Hari P (2008) An empirical model of stand GPP with the LUE approach: analysis of eddy covariance data at five contrasting conifer sites in Europe. Glob Change Biol 14:92–108. doi: 10.1111/j.1365-2486.2007.01463.x Google Scholar
- Reichstein M, Rey A, Freibauer A, Tenhunen J, Valentini R, Banza J, Casals P, Cheng YF, Grunzweig JM, Irvine J, Joffre R, Law BE, Loustau D, Miglietta F, Oechel W, Ourcival JM, Pereira JS, Peressotti A, Ponti F, Qi Y, Rambal S, Rayment M, Romanya J, Rossi F, Tedeschi V, Tirone G, Xu M, Yakir D (2003) Modeling temporal and large-scale spatial variability of soil respiration from soil water availability, temperature and vegetation productivity indices. Global Biogeochem Cy 17:1104–1116. doi: 10.1029/2003GB002035 CrossRefGoogle Scholar
- Vitale M, Mancini M, Matteucci G, Francesconi F, Valenti R, Attorre F (2012) Model-based assessment of ecological adaptations of three forest tree species growing in Italy and impact on carbon and water balance at national scale under current and future climate scenarios. Forest 5:235–246. doi: 10.3832/ifor0634-005 Google Scholar