The influence of land-use structures on the Lithuanian fluvial water quality

Abstract

The change in the concentration of biogenic substances (nitrates, phosphates) in the fluvial water is influenced by a number of factors, one of the main ones being diffusive pollution determined by the land-use structure of the watershed. More than a half of the territory of Lithuania is covered by the agricultural landed property; therefore its importance for the assessment of the surface water quality is certain. In order to evaluate the influence of the change in the land-use structure on the Lithuanian fluvial water, the article looks into the most characteristic Lithuanian watersheds. Forested territories are given particular attention since the distribution of forests, as a natural (or half-natural) ecosystem, in the watersheds and riversides determine the inflow of biogenic substances to the water-stream and their water quality. Therefore, the change of biogenic substances in the fluvial water is analysed having divided the object of the research, the watersheds, into three groups according to the average distances between forest arrays in riverside zones.