Abstract
Yarious geobotanical, photointerpretative, cartographical and pedological methods were used to study the vegetation and the habitat conditions under which it occurred in the valleys of a representative fragment of a young-glacial landscape. The author determined changes in the real and potential natural vegetation in lake depressions during their transformations into river valleys and then during the development of the latter. A geobotanical description has been worked out for various valley types (subglacial channels, river valleys, gullies and denudation-caused valleys) in a young-glacial landscape, taking into account the origin of the latter. The role has been established of denudation and erosion processes and their intensity as habitat-forming factors in the formation of contemporary vegetation of valleys. Relationships were determined between the vegetation and the age of slopes and soils, measured in absolute years, and then the resultant changes in the natural forest vegetation. A relationship has been revealed between the distribution of oak-hornbeam forests and beech forests in lowlands, and erosion and denudation processes, and habitat age. Relationships were determined between the vegetation and slope microrelief during its development, and the differentiation-causing effect of the direction of slope on the vegetation. The historical real vegetation of the period preceding the current wave of anthropopressure has been reconstructed and contemporary changes in valley vegetation have been interpreted. More information has been gained on the role of the direction of sloping as a community-forming factor. The vegetation was analysed from the viewpoint of its bioindicative potential.
Keywords
valleys; subglacial channels; river valleys; denudation-caused valleys; gullies; erosion; denudation; microrelief; slope direction; terrestrialization; young-glacial landscape; succession; historical real vegetation; contemporary real vegetation; potential natural vegetation; bioindication; vegetation mapping; aerial photo analysis; Kashubian Lakeland; northern Poland