The biophysics, ecology, and biogeochemistry of functionally diverse, vertically and horizontally heterogeneous ecosystems: the Ecosystem Demography model, version 2.2-Part 2: Model evaluation for tropical South America

Author(s):Show less -

Longo, Marcos ^{[1, 2, 3]} ; Knox, Ryan G. ^{[4, 5]} ; Levine, Naomi M. ^[6] ; Swann, Abigail L. S. ^[7] ; Medvigy, David M. ^[8] ; Dietze, Michael C. ^[9] ; Kim, Yeonjoo ^[10] ; Zhang, Ke ^[11] ; Bonal, Damien ^[12] ; Burban, Benoit ^[13] ; Camargo, Plinio B. ^[14] ; Hayek, Matthew N. ^{[15, 2]} ; Saleska, Scott R. ^[16] ; da Silva, Rodrigo ^[17] ; Bras, Rafael L. ^[18] ; Wofsy, Steven C. ^[2] ; Moorcroft, Paul R. ^[2]

Affiliation:Show less -

^[1] CALTECH, Jet Prop Lab, Pasadena, CA 91125 - USA

^[2] Harvard Univ, Cambridge, MA 02138 - USA

^[3] Embrapa Agr Informat, Campinas, SP - Brazil

^[4] Lawrence Berkeley Natl Lab, Berkeley, CA - USA

^[5] MIT, 77 Massachusetts Ave, Cambridge, MA 02139 - USA

^[6] Univ Southern Calif, Los Angeles, CA - USA

^[7] Univ Washington, Seattle, WA 98195 - USA

^[8] Univ Notre Dame, Notre Dame, IN 46556 - USA

^[9] Boston Univ, Boston, MA 02215 - USA

^[10] Yonsei Univ, Dept Civil & Environm Engn, Seoul - South Korea

^[11] Hohai Univ, Nanjing, Jiangsu - Peoples R China

^[12] INRA, UMR 1137, EEF, Champenoux - France

^[13] INRA, UMR EcoFoG 0745, Campus Agron, Kourou - France

^[14] Univ Sao Paulo, Piracicaba, SP - Brazil

^[15] NYU, New York, NY - USA

^[16] Univ Arizona, Tucson, AZ - USA

^[17] Fed Univ Western Para, Santarem, PA - Brazil

^[18] Georgia Inst Technol, Atlanta, GA 30332 - USA

• Document type: Journal article
• Source: Geoscientific Model Development; v. 12, n. 10, p. 4347-4374, OCT 14 2019.
• Web of Science Citations: 1

Abstract

The Ecosystem Demography model version 2.2 (ED-2.2) is a terrestrial biosphere model that simulates the biophysical, ecological, and biogeochemical dynamics of vertically and horizontally heterogeneous terrestrial ecosystems. In a companion paper (Longo et al., 2019a), we described how the model solves the energy, water, and carbon cycles, and verified the high degree of conservation of these properties in long-term simulations that include long-term (multi-decadal) vegetation dynamics. Here, we present a detailed assessment of the model's ability to represent multiple processes associated with the biophysical and biogeochemical cycles in Amazon forests. We use multiple measurements from eddy covariance towers, forest inventory plots, and regional remote-sensing products to assess the model's ability to represent biophysical, physiological, and ecological processes at multiple timescales, ranging from subdaily to century long. The ED-2.2 model accurately describes the vertical distribution of light, water fluxes, and the storage of water, energy, and carbon in the canopy air space, the regional distribution of biomass in tropical South America, and the variability of biomass as a function of environmental drivers. In addition, ED-2.2 qualitatively captures several emergent properties of the ecosystem found in observations, specifically observed relationships between aboveground biomass, mortality rates, and wood density; however, the slopes of these relationships were not accurately captured. We also identified several limitations, including the model's tendency to overestimate the magnitude and seasonality of heterotrophic respiration and to overestimate growth rates in a nutrient-poor tropical site. The evaluation presented here highlights the potential of incorporating structural and functional heterogeneity within biomes in Earth system models (ESMs) and to realistically represent their impacts on energy, water, and carbon cycles. We also identify several priorities for further model development. (AU)

• FAPESP's process: 15/07227-6 - Long term effects of forest degradation on carbon cycling in Amazonia
• Grantee: Marcos Longo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral