Trends in soil-land-use relationships in the Netherlands between 1900 and 1990

The distribution of agricultural land use today is less dependent on soil properties than in the past, as a result of technological advances. This fact has long been suspected by scientists from different disciplines, but the changing relationships between specific soil types and specific forms of land use have so far not been tested quantitatively. In this paper, we have quantified the association between soil type and land use for the Netherlands, for the years 1900, 1960, 1980 and 1990. For our analyses, we distinguished 21 soil groups and four land use classes. Cramer's V was used as a statistical measure to quantify the association. As a general trend, we find that associations are indeed weakening: intrinsically poor sandy soils became increasingly cultivated, while intrinsically rich soils are no longer reserved exclusively for crop cultivation. This general trend does not apply to all soil types, however: drift sands and other coarse sandy soils where large-scale mechanization was impeded by an undulating topography remained uncultivated. Moreover, even though the trend of a decrease in association is very clear we have several reasons to think that it may not decrease further in future. One reason is that inputs such as fertilizers which influenced the trend over the period 1900–1990, are nowadays less used than two decades ago as a result of environmental policies. Other reasons are the growing support for geoheritage and biodiversity