LAND COVER RESEARCH:
An Introduction

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There is considerable ignorance concerning the global distribution of vegetation type. This is an issue of increasing concern given the rate of transformation of the Earth's vegetation cover, and the profound impacts that these changes are having on the global environment and its habitability.

Changes in land cover for agriculture human settlements, and other purposes are among the most pervasive and obvious impacts of human activities on the global environment.

Changes in land cover have profound implications for the functioning of ecosystems, biogeochemical fluxes, and climate. Despite the fundamental transformations that humans have made to the surface of the Earth, there is no reliable, comprehensive data base of changes in the vegetative cover of the land surface on a global scale.

Notwithstanding recent advances in the estimation of biophysical characteristics such as leaf area index and canopy resistance, comprehensive derivation of canopy characteristics including nonfoliar properties must await the derivation of more refined procedures and better global data sets, which almost certainly will have to include microwave data. However, deriving maps of the current distribution of land cover classes and how they are changing is a much more feasible objective and hence current and future prospects will be evaluated for these tasks.