Abstract

An effective description of water transport in the soil-plant-atmosphere continuum (SPAC) is needed for wide-ranging applications in hydrology and climate-vegetation interactions. In this contribution, the theory of water movement within the SPAC is reviewed with emphasis on the eco-physiological and evolutionary constraints to water transport. The description of the SPAC can be framed at two widely separated time scales: (i) sub-hourly to growing season scales, relevant for hydro-climatic effects on ecosystem fluxes (given a set of plant hydraulic traits), and (ii) inter-annual to centennial scales during which either hydraulic traits may change, as individuals grow and acclimate, or species composition may change. At the shorter time scales, water transport can be described by water balance equations where fluxes depend on the hydraulic features of the different compartments, encoded in the form of conductances that nonlinearly depend on water availability. Over longer time scales, ontogeny, acclimation, and shifts in species composition in response to environmental changes can impose constraints on these equations in the form of tradeoffs and coordinated changes in the hydraulic (and biochemical) parameters. Quantification of this evolutionary coordination and the related tradeoffs offers novel theoretical tactics to constrain hydrologic and biogeochemical models. (C) 2012 Elsevier Ltd. All rights reserved.

Keywords

Soil-plant-atmosphere continuum; Transpiration; Vulnerability to cavitation; Water potential; Plant trait; Hydraulic conductivity

Published in

Advances in Water Resources
2013, Volume: 51, pages: 292-304
Publisher: ELSEVIER SCI LTD

UKÄ Subject classification

Forest Science
Geosciences, Multidisciplinary


Publication identifier

DOI: https://doi.org/10.1016/j.advwatres.2012.03.016

Permanent link to this page (URI)

https://res.slu.se/id/publ/44327