Nature conservation and protection of geological heritage have long traditions in Estonia. Already in 1910 the first nature reserve was established, and in 1935 the first nature protection law approved. In 1995, the Parliament of Estonia adopted the Act of Sustainable Development and in 1996, the Estonian Environmental Strategy was approved by the Government. Although small in area, Estonia is relatively rich in mineral resources (oil shale, phosphorites, peat, building materials, etc.), which together with large forested areas (about 50% of the territory) and high productivity agriculture have been and will be the basis for economy, and account for a substantial share in the Gross National Product. During the Soviet occupation, the soil cover of Estonia was subjected to severe degradation. About 1.9% of Estonian territory was used for military objects and these sites are still highly contaminated. Sharp increase in the exploitation of mineral resources has caused ever worsening impact on the environment. In the independent Republic of Estonia, nature conservation and mineral wealth protection gained importance of the first rate and the situation has improved.
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Konserwacja przyrody i ochrona dziedzictwa geologicznego mają już długą tradycję w Estonii. Pierwszy rezerwat przyrody został ustanowiony w 1910 r. W 1935 r. przyjęto pierwszą ustawę o ochronie przyrody. W 1995 r. parlament Estonii przyjął ustawę o zrównoważonym rozwoju, a w 1996 r. rząd zatwierdził Estońską Strategię Środowiskową. Chociaż niewielka, Estonia jest stosunkowo bogata w zasoby mineralne (łupki bitumiczne, fosforyty, torf, materiały budowlane itd.). Surowce te, wraz dużymi obszarami leśnymi (około 50% terytorium kraju) oraz wysoko produktywnym rolnictwem, będą podstawą gospodarki i wniosą duży wkład do dochodu narodowego. Podczas okupacji sowieckiej gleby Estonii poddane były poważnej degradacji. Około 1,9% terytorium Estonii wykorzystywane było na obiekty militarne. Tereny te są nadal silnie zanieczyszczone. Silny wzrost wydobycia surowców mineralnych także spowodował niekorzystny wpływ na środowisko. W niepodległej Republice Estonii konserwacja przyrody i ochrona bogactw mineralnych uzyskały pierwszorzędne znaczenie i ich sytuacja uległa poprawie.
Lake Vortsjärv is one of the biggest lakes in Eastern Europe and possesses a complex geological history. Bottom deposits consist mostly of fine sand and silt, accompanied with sapropel (up to 9 m thick) and lake marl (up to 8 m thick). In places, especially in the northern part where the bottom deposits are absent, varved clay or till are exposed in the lake basin. In the southern part of the lake the deposits are much thicker, indicating a gradual rise of water-level. Like the majority of lakes in the Northern Hemisphere, Lake Vortsjärv possesses a more open eastern and a more swampy and overgrown western bank. Shore types and the lithological composition of shore sediments are varied and highly controlled by the bedrock and glacial deposits. Long-shore transport of sediments is limited. The mineral composition of bottom sediments shows great qualitative and quantitative variability which relates to the grain-size and petrography of the parent deposits. Organic-rich sapropel can be used in agriculture and evidently also for medicinal purposes.
Subfossil mollusc shells are some of the most common remains in marine Quaternary sediments and can give precise information about the palaeogeographic conditions of palaeobasins. This is primarily due to their good preservation and the large number of species. They are widespread in nearly all biotopes and often occur in beach deposits, now lying at some distance inland above the present-day sea level. Molluscs are susceptible to the environment they inhabit and can therefore provide information about the substrata, water depth, salinity, temperature, isotopic composition of water and water-level fluctuations in ancient bodies of water. Molluscs can also be used in the stratigraphic subdivision and correlation of sediments. Conditions for the investigation of subfossil mollusc fauna in Estonia are extremely good. The bedrock in the coastal area consists mainly of limestones and dolomites, which are covered with carbonaceous till and limy aqueoglacial deposits. In Estonian offshore waters molluscs had suitable living conditions and sufficient material to build up the shells. In Estonia the Holocene mollusc fauna is much better preserved than in neighbouring countries.
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