Sedimentation and soil formation explained differences in facies and soil characteristics. The soils in this region were distinguished by strong influences of groundwater, resulting in severe compacting ('broek' soils) and human activity such as digging off dune sands ('afgeesten') and raising low-lying soils ('opvaren'). Van Liere used the best holding method to compare yields and growth on different soil types. This method compared well managed holdings, so that nonsoil factors were eliminated. The soil in profile pits and root distribution (mainly of grapes, tomatoes and cucumbers) were studied. Economic data (selling prices, production costs) were also considered. From the results ensued a suitability map for horticultural crops and a recommendation for some soil improvements, chiefly tile-drainage. Other methods (organic manuring and deep cultivation of subsoils) did not improve soils.
|Qualification||Doctor of Philosophy|
|Award date||16 Dec 1948|
|Place of Publication||'s-Gravenhage|
|Publication status||Published - 1948|
- soil surveys
- soil science