The representation of root processes in models addressing the responses of
vegetation to global change |
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Authors: | F I WOODWARD & C P OSBORNE |
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Institution: | Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK; Author for correspondence (tel +44 114 222 4374;fax +44 114 222 0002;e-mail ). |
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Abstract: | The representation of root activity in models is here confined to considerations of applications assessing the impacts of changes in climate or atmospheric CO2]. Approaches to modelling roots can be classified into four major types: models in which roots are not considered, models in which there is an interplay between only selected above-ground and below-ground processes, models in which growth allocation to all parts of the plants depends on the availability and matching of the capture of external resources, and models with explicit treatments of root growth, architecture and resource capture. All models seem effective in describing the major root activities of water and nutrient uptake, because these processes are highly correlated, particularly at large scales and with slow or equilibrium dynamics. Allocation models can be effective in providing a deeper, perhaps contrary, understanding of the dynamic underpinning to observations made only above ground. The complex and explicit treatment of roots can be achieved only in small-scale highly studied systems because of the requirements for many initialized variables to run the models. |
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Keywords: | vegetation model root resources water and nutrient uptake allocation |
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