The Landscape-Geographical Assessment of Sapropel Resource Capacity of Lubytivske Lake (Volyn Polessia)

Abstract

Purpose. To carry out the landscape and geographic assessment of sapropel resources of Lubytivske lake (Volyn Polessia) for the needs of balanced natural resource management of local areas. The research is based on complex physical and geographical methods, structural geographic modelling and landscape-limnological analysis from the assessment of natural aquatic complexes (NAC) of lakes. The results of the study have been presented in the form of a bathymetric model of the lake, a stratigraphic section of the bottom sediments of the reservoir, a block of hydrological, hydrochemical and geochemical parameters of the NAC. The peculiarities of composition, capacity, qualitative and quantitative characteristics of sapropel of Lubytivske lake have been revealed. With the use of GIS technologies and taking into account the features of the lake basin microrelief, lithology and bottom sediment capacity, hydrological and morphometric parameters of the reservoir, species composition of surface and underwater vegetation groups, and the seasonal state of the temperature regime, a landscape map of NAC of Lubytivske lake has been built. In the complex stow of the lake three aquaunderstows, in particular littoral, litho-sublittoral and profundal, and also eight types of aquatic facies have been pointed out. The landscape-metric estimation of the morphological structure of the NAC of the lake has been carried out and the areas of aquatic facies and aquastows, as well as their correlation in percentages, have been given. The attention has been focused on littoral aquastow of the lake, that receives the major anthropogenic transformations as a result of economic activity (the flows of nutrients from garden areas, recreational fishing, walking of poultry, etc.) and the decrease of groundwater level and significant waterlogging. Conclusions. More than 70.0% of the basin of Lubytivske lake is filled with organic minerals, which can be used as fertilizers in the agricultural sector. Resource exploitation for the production of sapropel will allow to extend the reservoir and slow down the landscape-succession processes of ageing of the lake, as well as create favourable conditions for recreational − activities. The estimation of lake sapropel resources should be the basis of the strategy of balanced natural resource management of Lubitivska united territorial community.