Water in the unsaturated zone

Abstract

Knowledge about the spatial variability of soil water is of great importance for understanding the hydrology of a certain area. The theories of water flow in the unsaturated zone are rather well established, and many models suit the theories very well. A serious problem today seems to be how to verify the models in the field and to study how well they reflect spatial variability. Few models usen in Norden today are based directly on field measurements of spatial variability. In many cases they represent vertical water movement at one point. This is not because spatial variabilitycannot be modelled, but merely because there are no field data to be used in the models.

In order to discuss these questions, a NHP-seminar was arranged in the regi of the Norwegian National Committee for Hydrology in January 1986. About 50 individuals, most of them soil scientists and hydrologists from Denmark, Norway, Sweden and Finland, and two from the United Kingdom representing the Institute of Hydrology and Soil Survet of England & Wales, respectivly, participated in the seminar.

The aim of the seminar was to discuss "the state of the art" in Norden today. What types of data on spatial varitability do exist, in which way are they applied, which data types are most important for future work and how can they be used in modelling? Indeed, the seminar did not give give answers to all these questions. But it hopefully may be an inspiration for further contact and more specific cooperation in the future.

(The preface)