Quantitative assessment of the species diversity of the planet (Global, 2001)
|Kingdoms||Number of described species||Total number of species (estimated)|
On other hand, many species are under threats of extinction, and situation is getting worse and worse. Extinction of species is irreversible process leading to deterioration of the ecosystem. Scientific assessments based on geological data shows that “normal” average rate of species extinction is five multi cellular organisms as per two years. The same indicator for vertebrates is much less; “normally”, the planet is losing one bird species per 400 years and one species of mammals per 800 years. Regretfully, real picture is different. According to the preliminary estimations, 350 species of vertebrates and 400 species of invertebrates were disappeared from the planet during last 400 years. It means that registered losses are as much higher as hundreds times as to compare to estimated figures.
There are two main causes of biodiversity deterioration. The first very obvious cause of the decreasing of human populations’ number is uncontrolled and unsustainable extermination of living organisms, first of all fauna species representing some values for humanity. The second, not less important cause is as well human activity aimed at extension of the habitat areas. Urbanisation and development of rural settlements, extension of arable lands for agricultural practices, industrial constructions, building the roads and pipelines, increasing the shipping activities, natural resources extraction and other kinds of economic activity inevitably decreasing the habitat areas of wild plants and animals. Both direct (extermination of organisms) and indirect (destroying the natural habitats) influence of human activity are key treats for biodiversity.
Few hundreds years ago, territory of modern Ukraine was covered by forests (55%), steppes (32%), wetlands (5%), meadows 1%). However, since beginning of the 20th century the picture has been significantly changed. As of now (2007), the forests are covering only 14,6% of the territory of the country and half of them are man-made ones. Steppes represent less than 1% of territory, bogs and swamps – 3%, meadows’ area has been increased up to 9%, and arable lands cover 56% of the country (highest level in Europe). 30% of arable lands are deteriorated by erosion. Sharp decrease of territory of virginal natural lands causes significant reduction of habitats of wild species of animals and plants.
Biodiversity conservation is aimed at achievement at least of two objectives: first one is conservation of genetic resources constituting basis of species diversity, and second one is conservation of etalon ecosystems of biosphere for sustainable development and reproducing of species.
There are two systematic practical approaches for biodiversity conservation. Approach in-situ is focused on conservation of biodiversity at natural conditions. Approach ex-situ envisages conservation of organisms and their derivatives in artificial conditions out of ecosystems and native habitats. Both of them are important and mutually complementary.
An important instruments for the co-operative rebuilding of ecologically-friendly societies are to be 1) a co-coordinated system of national eco-law, being based on principles and decisions of global and regional conventions, 2) the strengthening policies to develop ecological alternatives (for example, via environmentally sound technical and technological assistance) and technological re-orientation, 3) making global financial-economic and banking spheres environmentally responsible and the development of system of global, regional and national environmental responsibility, inter alia, through global and regional conventions, agreements and commitments 4) the development of international innovative environmental institutions for the purpose of insuring synergetic development (the best example now is the Global Environment Facility, GEF), 5) the “greening” of local communities.
Ukraine re-gained its independence in 1991 and as a typical representative of a post-communist society, it inherited from the previous system long series of problems related to the environment, including unsustainable exploitation of natural resources, particularly mineral deposits, and bioresources (forests and wildlife), water, air and soil pollution, land erosion, radionuclide contamination. Due to extensive agricultural activity steppe landscapes were mitigated. It could be quite difficult to implement sustainable development policy even under favorable conditions of a prosperous economy, thus it is even more difficult to pursue this goal in Ukraine, since the country is now undergoing dramatic changes, trying to overcome a profound crisis and to resolve numerous particular problems. It is important to consider on thia way the process of development of the legal system, the system of socio-economic motivation of eco-sustainable activity and alternatives, opportunities, connected with international cooperation, regional and local challenges and expectations.
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