How do antecedent (past) conditions influence land-carbon dynamics after those conditions no longer persist? In particular, quantifying such memory effects associated with the influence of past environmental (exogenous) and biological (endogenous) conditions is crucial for understanding and predicting the carbon cycle. Here we show, using data from 42 eddy covariance sites across six major biomes, that ecological memory-decomposed into environmental and biological memory components-of daily net carbon exchange (NEE) is critical for understanding the land-carbon metabolism, especially in drylands for which memory explains similar to 32% of the variation in NEE. The strong environmental memory in drylands was primarily driven by short- and long-term moisture status. Moreover, the strength of environmental memory scales with increasing water stress. This universal scaling relationship, emerging within and among major biomes, suggests a potential adaptive response to water limitation. Our findings underscore the necessity of considering ecological memory in experiments, observations and modelling.
1.Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA 2.No Arizona Univ, Sch Informat Comp & Cyber Syst, Flagstaff, AZ 86011 USA 3.Woods Hole Res Ctr, Falmouth, MA USA 4.No Arizona Univ, Ctr Ecosyst Sdence & Soc, Flagstaff, AZ 86011 USA 5.No Arizona Univ, Dept Biol Sci, Flagstaff, AZ 86011 USA
Recommended Citation:
Liu, Yao,Schwalm, Christopher R.,Samuels-Crow, Kimberly E.,et al. Ecological memory of daily carbon exchange across the globe and its importance in drylands[J]. ECOLOGY LETTERS,2019-01-01