Semi-empirical modeling of abiotic and biotic factors controlling ecosystem respiration across eddy covariance sites

Mirco Migliavacca (1, 2) , Markus Reichstein (2) , Andrew D. Richardson (3) , Roberto Colombo (1) , Mark A. Sutton (4) , Gitta Lasslop (2) , Georg Wohlfahrt (5) , Enrico Tomelleri (2) , Nuno Carvalhais (2, 6) , Alessandro Cescatti (7) , Miguel Dario Mahecha (2, 8) , Leonardo Montagnani (9) , Dario Papale (10) , Sönke Zaehle (11) , M Altaf Arain (12) , Almut Arneth (13) , T Andrew Black (14) , Sabina Dore (15) , Damiano Gianelle (16) , Carole Helfter (4) , David Hollinger (17) , Werner L Kutsch (18) , Beverly E. Law (19) , Peter M Lafleur (20) , Yann Nouvellon (21) , Corinna Rebmann (22, 23) , Humberto R. da Rocha (24) , Mirco Rodeghiero (16) , Roupsard Olivier (21, 25) , Maria-Teresa Sebastià (26, 27) , Guenther Seufert (7) , Jean-Francoise Soussana (28) , Michiel K van Der Molen (29)

1 Remote Sensing of Environmental Dynamics
2 Department of Biogeochemical Integration [Jena]
3 OEB - Department of Organismic and Evolutionary Biology [Cambridge]
4 Edinburgh Research Station
5 Institute of Ecology
6 FCT NOVA - Faculdade de Ciências e Tecnologia = School of Science & Technology
7 IES - JRC Institute for Environment and Sustainability
8 D-USYS - Department of Environmental Systems Science [ETH Zürich]
9 Servizi Forestali
10 DISAFRI
11 Biogeochemical Systems Department [Jena]
12 School of Geography & Earth Sciences
13 Department of Physical Geography and Ecosystem Science [Lund]
14 Faculty of Land and Food Systems
15 School of Forestry
16 Centro di Ecologia Alpina
17 NE Research Station
18 Institut für Agrarrelevante Klimaforschung
19 College of Forestry [Corvallis]
20 20- Department of Geography
21 Cirad-PERSYST - Département Performances des systèmes de production et de transformation tropicaux
22 Department Biogeochemical Processes [Jena]
23 Micrometeorology Group [Bayreuth]
24 Department of Atmospheric Sciences [São Paulo]
25 CATIE - Centro Agronómico Tropical de Investigación y Enseñanza - Tropical Agricultural Research and Higher Education Center
26 Agronomical Engineering School
27 Laboratory of Plant Ecology and Botany
28 INRA - Institut National de la Recherche Agronomique
29 Department of Hydrology and Geo-Environmental Sciences [Amsterdam]

In this study we examined ecosystem respiration (RECO) data from 104 sites belonging to FLUXNET, the global network of eddy covariance flux measurements. The main goal was to identify the main factors involved in the variability of RECO: temporally and between sites as affected by climate, vegetation structure and plant functional type (PFT) (evergreen needleleaf, grasslands, etc.). We demonstrated that a model using only climate drivers as predictors of RECO failed to describe part of the temporal variability in the data and that the dependency on gross primary production (GPP) needed to be included as an additional driver of RECO. The maximum seasonal leaf area index (LAIMAX) had an additional effect that explained the spatial variability of reference respiration (the respiration at reference temperature Tref=15°C, without stimulation introduced by photosynthetic activity and without water limitations), with a statistically significant linear relationship (r2=0.52 p<0.001, n=104) even within each PFT. Besides LAIMAX, we found that the reference respiration may be explained partially by total soil carbon content. For undisturbed temperate and boreal forest a negative control of the total nitrogen deposition on the reference respiration was also identified. We developed a new semi-empirical model incorporating abiotic factors (climate), recent productivity (daily GPP), general site productivity and canopy structure (LAIMAX) which performed well in predicting the spatio-temporal variability of RECO, explaining >70% of the variance for most vegetation types. Exceptions include tropical and Mediterranean broadleaf forests and deciduous broadleaf forests. Part of the variability in respiration that could not be described by our model could be attributed to a range of factors, including phenology in deciduous broadleaf forests and management practices in grasslands and croplands.

Mots clés: Life Sciences

Domaines: Sciences du Vivant [q-bio]

Mirco Migliavacca, Markus Reichstein, Andrew D. Richardson, Roberto Colombo, Mark A. Sutton, et al.. Semi-empirical modeling of abiotic and biotic factors controlling ecosystem respiration across eddy covariance sites. Global Change Biology, 2010, 17 (1), pp.390. ⟨10.1111/j.1365-2486.2010.02243.x⟩. ⟨hal-00599515⟩