Examining the Role of Environmental Memory in Carbon and Water Fluxes across Australian Ecosystems
Abstract
Terrestrial ecosystem fluxes respond to climatic drivers across multiple time scales (seconds to decades), with many processes influenced by antecedent conditions. These lagged responses, both their strength and time scales, are poorly understood and have been relatively overlooked in the development of terrestrial biosphere models and their hypotheses. By using data from eddy covariance sites covering two rainfall gradients in Australia, in combination with a hierarchical Bayesian model, we characterised the timescales of influence and strength of antecedent climate drivers on fluxes of net carbon exchange and evapotranspiration. When considered at a continental scale, we found that both fluxes are more predictable when legacy effects are introduced to the model. The importance of ecological memory in predicting fluxes increased as water availability declines. However, this relationship does not necessarily hold at the local level, with confounding impacts from site heterogeneity. Our results therefore underline the importance of both capturing legacy effects in terrestrial biosphere models used to project responses in water limited ecosystems, while also considering the role of individual site characteristics.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.B52C..04P