Vegetation and soil of a White-Sand Savanna in Suriname

This thesis describes the vegetation and discusses the prevailing ecological factors of a savanna region near Jodensavanne, Suriname; savanna being defined in this context as a landscape with low and often open woody vegetation, relieved by tracts with a thin to dense cover of herbs. The methodology of the French-Swiss school of phytosociologists appeared appropriate for semi-quantitative description of the vegetation but, because of the limited scope of the study, it was considered premature to apply the synsystematic rules of this school, so the established units are called “major vegetation types”, with “variants”, “subvariants” and “facies” as subunits. Three major vegetation types of scrub and five of herb vegetation are described in detail and some attention has been given to the surrounding woods and forests. Except for small fringe areas, the savanna is limited to rather coarse white-sandy soils, the characteristics and genesis of which are discussed. It is demonstrated that the hardpan which occurs in places is a paleopedogenelic feature and that this hardpan does not influence the presentday drainage conditions, for the drainage pattern could be explained on the basis of topography alone. The drainage condition which is one of the more important edaphic factors affecting the vegetation, allows a division of the vegetation types into two groups, one representing the “dry savanna” and the other the “wet savanna”. On the wet savanna much of the differentiation in the herb vegetation is produced by water flowing over the soil. Some direct results of burning could be analyzed, but about the long term effects of fire only suppositions could be made.