Water release through plant roots: new insights into its consequences at the plant and ecosystem level

Summary Hydraulic redistribution (HR) is the passive movement of water between different soil parts via plant root systems, driven by water potential gradients in the soil–plant interface. New data suggest that HR is a heterogeneous and patchy process. In this review we examine the main biophysical and environmental factors controlling HR and its main implications at the plant, community and ecosystem levels. Experimental evidence and the use of novel modelling approaches suggest that HR may have important implications at the community scale, affecting net primary productivity as well as water and vegetation dynamics. Globally, HR may influence hydrological and biogeochemical cycles and, ultimately, climate. Contents Summary 830 I. Introduction 830 II. Mechanisms controlling HR 832 III. Below‐ground processes affected by HR 833 IV. Ecological implications of HR 835 V. Concluding remarks 838 Acknowledgements 839 References 839