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Ecohydrological Optimality

Part 1. Theory, Organization and Scale

  1. Stanislaus J. Schymanski1,
  2. Axel Kleidon1,
  3. Michael L. Roderick2

Published Online: 15 SEP 2009

DOI: 10.1002/0470848944.hsa319

Encyclopedia of Hydrological Sciences

Encyclopedia of Hydrological Sciences

How to Cite

Schymanski, S. J., Kleidon, A. and Roderick, M. L. 2009. Ecohydrological Optimality. Encyclopedia of Hydrological Sciences. 1.

Author Information

  1. 1

    Max-Planck-Institute for Biogeochemistry, Jena, Germany

  2. 2

    Australian National University, Canberra, Australia

Publication History

  1. Published Online: 15 SEP 2009


Hydrological systems are governed by an incredible wealth of interactive processes, ranging from small-scale processes within the soil domain such as unsaturated flow, bioturbation, and root water uptake to large-scale feedbacks between the water balance and the global atmospheric circulation. Optimality approaches aim toward a simpler and more general representation of hydrological systems. As the hydrology of land is strongly affected by the presence of vegetation, these optimality approaches generally need to be explored in the context of how purely hydrological processes are linked to ecological processes. This article summarizes the different optimality assumptions that have been used to describe ecohydrological processes and how these are related to each other. Most approaches can be classified as either physical or ecological optimality. A range of examples are given for applying optimality approaches at various temporal and spatial scales, ranging from the scale of individual leaves and how they control water loss in relation to carbon uptake to the larger scale attributes of vegetation types, ecosystem properties, and river basin networks. The article concludes with a discussion of the usefulness of optimality approaches and their advantages as well as their disadvantages and the need for improvement.


  • hydrology;
  • optimality;
  • ecohydrology;
  • vegetation;
  • adaptation;
  • thermodynamics