Publications

Xu, XL (2022). Global patterns and ecological implications of diurnal hysteretic response of ecosystem water consumption to vapor pressure deficit. AGRICULTURAL AND FOREST METEOROLOGY, 314, 108785.

Abstract
Increasing vapor pressure deficit (VPD) has led to widespread reductions in vegetation carbon uptake by stomatal hydraulic regulation. The response of vegetation to VPD is therefore paramount in the global water and carbon cycle, and draws worldwide attention. However, the hysteretic response of ecosystem water consumption to VPD, although widely reported across the world, is still lack of systematic and consistent research on its global patterns and ecological implications. Based on a newly developed hourly dataset of land-atmosphere fluxes, this study finds that hysteresis increases with climatic aridity and long hysteresis mainly occurs in water-limited areas; the hysteretic response of water consumption to VPD for woody ecosystems is shorter than that for the herbaceous ecosystems; interestingly, gross primary productivity (GPP) increases with hysteresis at the high hysteresis ends in dry environments (dry-humid, semi-arid and arid zones), which might suggest an existence of drought-adapting mechanisms of vegetation growth that is relevant to hysteresis but overlooked before. This study provides important information for projecting future shifts of ecosystem functions under increasing atmospheric dry stress.

DOI:
10.1016/j.agrformet.2021.108785

ISSN:
1873-2240