Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Historical land use dataset

A spatially explicit, global-scale dataset of crop and pasture area for each year from 1700-1900 was constructed by merging, interpolating and reconciling two independent source datasets (Klein Goldewijk 2001, Ramankutty and Foley 1999). These data may be used as input to Terrestrrial Ecosystem Models, which require anthropogenic disturbance as a forcing.

The construction of annual pasture fraction datasets based on KG required interpolation and a number of assumptions regarding fractional coverage and the exact nature of grazing land. WRT the latter it is important to know its history as that determines to a large extend the (soil) carbon pool: is it intensively grazed land converted from either natural grassland or forest, or is it natural grassland. In the absence of more precise information, datasets of the fractional coverage of pasture at years other than 1700, 1750, 1800, 1850, 1900, 1950, 1970 and 1990 were obtained by simple linear interpolation between those dates.

In many grid squares it was necessary to deal with the dual presence of both pasture from KG and crops from RF, as a result of which a grid square could contain a pasture fraction of 1.0 and also a non-zero crop fraction, giving a total "disturbed fraction" greater than 1.0. The crop and/or pasture fractions are therefore adjusted in order to avoid total disturbed fractions of more than 1.0. 0.

The final datasets provide fractional coverage of crops and pastures at 0.5 resolution, each year from 1700 to 1990.

Reported by

Met Office
London Road, Sutton House
United Kingdom