Preprints
https://doi.org/10.5194/bg-2022-25
https://doi.org/10.5194/bg-2022-25
 
31 Jan 2022
31 Jan 2022
Status: a revised version of this preprint is currently under review for the journal BG.

Observed Water- and Light-Limitation Across Global Ecosystems

François Jonard1,2, Andrew F. Feldman3,4, Dan J. Short Gianotti5, and Dara Entekhabi5 François Jonard et al.
  • 1Earth Observation and Ecosystem Modelling lab, SPHERES research unit, Université de Liège (ULiege), Allée du Six Août 19, 4000 Liège, Belgium
  • 2Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Germany
  • 3NASA Postdoctoral Program, NASA Goddard Space Flight Center, Greenbelt, MD, USA
  • 4Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA
  • 5Parsons Laboratory, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA

Abstract. With a changing climate, it is becoming increasingly critical to understand vegetation responses to limiting environmental factors. Here, we investigate the spatial and temporal patterns of light and water limitation on photosynthesis using an observational framework. Our study is unique in characterizing the nonlinear relationships between photosynthesis and water and light, acknowledging approximately two regime behavior (no limitation and varying degree of limitation). It is also unique in using an observational framework instead of using model-derived photosynthesis properties. We combine data from three different satellite sensors, i.e., solar-induced chlorophyll fluorescence (SIF) from TROPOMI, surface soil moisture from SMAP, and above-ground canopy density from MODIS. We find both single-regime and two-regime models describe SIF sensitivity to soil moisture and photosynthetically active radiation (PAR) across the globe. The distribution and strength of soil moisture limitation on SIF are mapped in the water-limited environments while distribution and strength of PAR limitations are mapped in the energy-limited environments. Two-regime behavior is detected in 73 % of the cases for water limitation on photosynthesis, while two-regime detection is much lower at 36 % for light limitation on photosynthesis. SIF sensitivity to PAR strongly increases along moisture gradients, reflecting mesic vegetation’s adaptation to making rapid usage of incoming light availability on the weekly timescales. The transition point detected between the two regimes is connected to soil type and mean annual precipitation for the SIF-soil moisture relationship and for the SIF-PAR relationship. These thresholds have therefore an explicit relation to properties of the landscape, although they may also be related to finer details of the vegetation and soil interactions not resolved by the spatial scales here. The simple functions and thresholds are emergent behaviors capturing the interaction of many processes. The observational thresholds and strength of coupling can be used as benchmark information for land surface and Earth system models, especially those that characterize gross primary production mechanisms and vegetation dynamics.

François Jonard et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Review of bg-2022-25 “Observed Water- and Light-Limitation Across Global Ecosystems“', Rene Orth, 04 Mar 2022
    • AC1: 'Reply on RC1', François Jonard, 03 Apr 2022
  • RC2: 'Comment on bg-2022-25', Anonymous Referee #2, 05 Mar 2022
    • AC2: 'Reply on RC2', François Jonard, 03 Apr 2022

François Jonard et al.

François Jonard et al.

Viewed

Total article views: 433 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
305 111 17 433 31 6 5
  • HTML: 305
  • PDF: 111
  • XML: 17
  • Total: 433
  • Supplement: 31
  • BibTeX: 6
  • EndNote: 5
Views and downloads (calculated since 31 Jan 2022)
Cumulative views and downloads (calculated since 31 Jan 2022)

Viewed (geographical distribution)

Total article views: 403 (including HTML, PDF, and XML) Thereof 403 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 02 Jul 2022
Download
Short summary
We investigate the spatial and temporal patterns of light and water limitation on photosynthesis. Using satellite observations, we find both single- and two-regime models describe sun-induced chlorophyll fluorescence (SIF) sensitivity to soil moisture (SM) and photosynthetically active radiation (PAR). The distribution and strength of SM limitation on SIF are mapped in the water-limited environments, while distribution and strength of PAR limitation are mapped in the energy-limited environments.
Altmetrics