INFLUENCE OF MORPHOMETRIC PARAMETERS OF RIVER BASINS ON TAXONOMIC RICHNESS OF FLORA (BY THE EXAMPLE OF THE TOM RIVER BASIN)

Abstract

The article deals with methodological issues of studying the influence of morphometric parameters of model basins (size, nature of the river network, shape) of the Tom river on the taxonomic structure of flora. Taking into account significant differences in the morphometric of river basins, which determine the diversity of environmental conditions in the Tomi river basin, 22 model basins were identified. Morphometric of model basins is determined by 25 parameters characterizing the main sizes of basins (area, length, width, height, etc.), features of the river network (length and number of rivers, etc.), as well as various forms of river basins. The indicators of floristic wealth are accepted: the number of species, the number of genera and the number of model pool families. The author considers the conditionality of taxonomic diversity of flora by morphometric characteristics of basins for three levels-species, genus and family. Morphological parameters of model basins vary widely, which determines the diversity of plant habitats. However, the size, features of the river network and shape are not equivalent to the richness of the flora. Taxonomic richness at each level (species, genus and family) depends primarily on the morphometric of river basins. It is established that the altitude parameters are significant, especially the maximum height, the amplitude of the height or fall of the river, and the dependence is high (α = 0,05 df = 20). The nature of the river network and the shape of the basins for taxonomic richness are not essential. The most important morphometric features of basins by the number of taxa of different hierarchical ranks include the same set of parameters of the basin, primarily the height and their maximum values, the amplitude of fluctuations in the height or fall of the river. At the species level, the significance of other parameters is much lower. A similar relationship is obtained at the genus and family levels. This changes not only the proximity of the relationship with the change in taxonomic rank, but also the number of the most significant morphometric parameters. The article contains 10 Tables, 27 References.