Links between some important Lithuanian macrophytes and land use & cover types

Abstract

Permanent extension of anthropogenic activities and severe climatic fluctuations threaten the sustainability of ecosystems worldwide. Recently, there has been an increasing attention on ensuring the sustainable use of agricultural, forest and aquatic ecosystems while preserving biodiversity and ecosystem services. Climate change may have various forms and extent depending on geographic region and habitat type. Extreme climate change is likely to have a negative impact on aquatic ecosystems. In order to predict and control the status of the surface waters, it is important to get ideas about the changes in the concentration of key chemicals / nutrients. Nitrogen deposition data together with inland water parameters provide message that nitrogen loads may affect the vegetation of the Baltic States. The aim of this study was to determine the concentrations of nitrogen as the most important nutrient element among the seven most common riparian plants of Lithuania and to evaluate the relations with land use and cover types in the context of changing climate. The mean values (N % of dry mass, DM) of the leaf N concentration, of selected aquatic macrophytes were as follows: Lythrum salicaria (3.0) < Stuckenia pectinata (3.1) < Phalaris arundinacea (3.5) < Bidens frondosa (3.8) < Phragmites australis (4.0) < Nuphar lutea (4.1) < Echinocystis lobata (4.2). Use of the CORINE land cover classification revealed, that in riparian sampling sites, neighboring areas were of agricultural use as predominant type of the cover (for 6 out 7 species), while Bidens frondosa was dominated besides artificial cover. Stuckenia pectinata was not observed near the areas of artificial cover. Classification of water macrophytes according to their geographical location and water pollution in 1992–1996 in the fragments of the rivers bordering agricultural areas, did not reveal differences in leaf nitrogen concentrations.[...]