Мартынюк В. А.

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 re-source management of Lubitivska united territorial community.

Purpose. To substantiate the features of the landscape-geographic model of the ecological passport of the lake basin for the needs of preserved and recreational nature management. The article is focused on the acute need in development of ecological passports of local environmentally protected sites for formation of a regional inventory of nature reserve fund. The concept of a natural aquatic complex (NAC) of the lake, a lake-basin system (LBS) served as a methodological basis of the proposed work. The research is based on the methods of field instrumental landscape-limnological searches with the use of laboratory diagnostics of soil samples of the catchment and bottom sediments of the lake, and the landscape-based analysis of the LBS. The results of the study are presented in the form of landscape models of NAC of Ozertse lake and the natural territorial complexes (NTC) of the catchment. Landscape complexes of the rank of a tract and aquatic facies are allo-cated in the OBS of Ozertse lake. The geochemical features of the bottom sediments of the water body on the example of one of the points of sounding, hydrological and morphologic-morphometric parameters of NAC of the lake and its catchment, and the landscape-metric characteristics of the integrated lake-basin system are analysed. Conclusions. The developed landscape-geographic model of the lake basin system will be a base for the ecological passport of Ozertse lake. Ecological passports of such type are needed for ecological, tourist-recreational, water management and land reclamation institutions and establishments, as well as for the newly formed united territorial communities.

The map of landscape structure of key area «Lake Tuhove» (Scale 1:10000) and the natural aquatic complex of the lake (Scale 1:2000) on the level of urotshistshes, complex and aquaurotshistshe and aquafacies was made as the results of field researches. The main morphometric and hydrological parameters of the lake were calculated, and the characteristics of the territorial division of the natural aquatic complex were justified. Some parameters of hydrochemical state of the lake in comparison with the data of 50 years 20th century were made. Some geochemical characteristics of sediments of reservoir and soils, adjacent geocomplexes of lake Tuhove were analyzed. It was proposed lake Tuhove with surrounding geocomplexes to attribute to the reserve area «Somyno» of Rivne Natural Reserve.