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Environmental problems of Northern Eurasia

Nature Protection and Conservation

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Geography of Biodiversity and Human Impact

The biodiversity of Northern Eurasia is controlled by the size of the region, the alternation of mountains and plains, the relatively young age of its landscapes, and biogeographic homogeneity (the whole territory belongs to the single Holarctic region). In the regions with a long history of economic development, the human factor is important. However, due to the vastness of the territory and low population density, natural environments of Northern Eurasia have been transformed less than those of Western and Central Europe, and southern and south-eastern Asia.

The prevalence of plains predetermines a free exchange of biota with the Mediterranean region in Europe and the Turanian plain in Asia. In the north, the Arctic Seas serve as migration passageways for the circumpolar Arctic and boreal species. Therefore, over most of Northern Eurasia there are few endemics (Shvarts et al., 1996). In the Quaternary, six major wet-dry and warm-cool climatic cycles occurred accompanied by the migration of biota and the formation of refugia where relict species survived. In the south, the high mountains of the Transbaikal region, the Sayans, Altay, Tien-Shan, Pamir, Kopetdagh, and the Caucasus served as refugia and are characterized by relatively high endemism. At present, they form a biogeographic barrier in the path of biotic exchange. Areas with relict biota include regions with calciferous flora in the European Russia and fragments of relict steppes in the north-east of Siberia.

The dense hydrological network also contributes to the species exchange. Most of the rivers have meridional courses which facilitate south-north migration (e.g., migration of the taiga species to tundra, nemoral species to taiga, steppe species to forests, and the more hygrophilous species of plants and animals to the arid zone). The abundance of rivers, lakes, and bogs leads to a high share of water and circumaqueous species of plants, birds, and mammals in the composition of biota. Across most of the territory, winter temperatures are negative and the participation of thermophilic (subtropical and tropical) plants and animals is insignificant in comparison with northern species and limited to geographically small areas in Central Asia and Transcaucasia.

There are many biogeographical divisions of Northern Eurasia. The following classification is commonly accepted: polar deserts; arctic and subarctic tundras; forest-tundra; northern, central and southern taiga; larch and thin forests; mixed coniferous and broad-leaved forests; broad-leaved forests; forest-steppe; grasslands; moderately dry and dry steppes; semi-desert, and desert biomes. In addition, there are intrazonal ecosystems such as swamps, oligotrophic, mesotrophic, and eutrophic bogs, floodplain meadows and forests, and mountain biomes. Composition of biomes is discussed in Chapter 7 and Chapters 8-18, and this section will focus on rare and endangered species.

The circumpolar biome of polar deserts, which covers the Arctic islands and archipelagoes (Figure 8.9), is characterized by low biological diversity because of the young age of the landscapes and climatic extremes. There is an absolute predominance of lower plants (i.e., algae, lichens, liverworts, and mosses) in the vegetation of polar deserts which form a fine film of life together with a few flowering plants. Local floras (defined as flora of an area of 100 km2) contain as few as 20-30 species of vascular plants. About 60 plant species are known on Franz Josef Land (Aleksandrova, 1988). Typical species of the vertebrates are associated with the sea, such as polar bear, polar fox, walrus, and seals (Kalyakin, 1996). Until 1956, when hunting was banned, the population of polar bear had been declining. Now the main threat to this species is posed by oil pollution which can affect the animals either through the swimming in water covered by an oil film or through the contamination of the food chain (Belikov, 1993). Landscapes and biota of the arctic tundra biome are conserved in one zakaznik, Zemlia Frantsa losifa on Franz Josef Land.

The circumpolar biome of the arctic tundra occurs on the Arctic islands and forms a narrow strip along the continental Arctic coast in Asia (Figure 8.9). Typical landscapes are those of coastal plains with polygonal and spotted (medallion) tundras, polygonal mires, and saline marshes of the deltas. Local floras of this biome comprise 70-100 species and there is a larger share of flowering plants and mosses than in the polar deserts. Vertebrate fauna is represented by reindeer, polar fox, lemmings, geese, alpine ptarmigan, numerous species of diving ducks, and sandpipers. Rare and endangered species are few in number and include mainly animal and bird species, such as walrus, Bewick's swan, snow goose, and barnacle goose. Biota and landscapes of the arctic tundra are protected in the nature reserves of Bolshoy Arktichesky on the Taymyr peninsula and the nearby islands, Ust-Lensky in the delta of the Lena and Ostrov Vrangela on Wrangel island. In the last three decades, the environments of Kolguev Island, Yamal, and Gydan peninsulas have been seriously damaged by oil and gas development as well as the archipelago of Novaya Zemlia which accommodates a former nuclear test site.

The main feature of the subarctic tundra (Figure 8.9) is its remarkably diverse moss flora. Locally, it may include as many as 150-200 species. Shrubs, dwarf shrubs, and sedges are abundant. Local floras of vascular plants are twice as rich in comparison with the arctic tundra and contain 250-300 species (Tishkov, 1996). Vertebrate fauna is also more diverse. Between 70-100 bird species and about 20-25 mammal species are found locally. Because of the great extent of wetlands, there are many hydrophilous species among birds and the 'bog' species of sandpiper are among the main dominants in the bird population. In addition to the Arctic species, many boreal species are common and abundant in the subarctic tundra. River ducks and the bluethroat are good examples of this. In the subarctic tundra, their population is bigger than in forests which are their primary habitats (Chernov and Matveeva, 1997). The avifauna includes a number of rare birds such as gyrfalcon, rare species of swans, geese, and barnacle goose. In some areas, the bird population is in decline because of the worsening environmental conditions in the southerly regions where birds winter. An example of this is the red-breasted goose that breeds in tundra and winters in Transcaucasia. In the early 1960s, about 25 000 of these birds wintered in wetlands around the Kura and Araks. However, wintering conditions deteriorated markedly as rivers became dammed and water was diverted for irrigation. In the mid-1970s, only a few dozens of these birds were wintering there and their number in the Arctic also dropped sharply (Pryde, 1991). In European Russia, the biota of the subarctic tundra is conserved in the Lapland zapovednik on the Kola peninsula; in Siberia, there are three zapovedniks (Taymyrsky and Putoransky on the Taymyr peninsula, and Ust-Lensky), two national parks (Nenets and Bering) and a few zakazniks (Yablokov et al., 1996).

Much of the northern part of European Russia and most of Siberia are occupied by the biome of boreal coniferous forests which is also known as taiga (Figure 9.2).

Subzones and longitudinal sectors within the taiga zone

Fig. 9.2 Subzones and longitudinal sectors within the taiga zone

Despite a comparatively high landscape diversity, the vegetation is monotonous and species-poor in comparison with most other forest types. The dark-coniferous taiga is represented by just a few tree species (Picea abies, P. obovata, Abies sibirica, Pinus sibirica, P. sylvestris, and species of Larix). The local vascular floras contain 400-700 species, there are 120-150 species of nesting birds and 40-50 mammal species (Biological Diversity, 1995). There are no endemics in the flora and fauna of the taiga and there are few rare species (Red Data Book, 1995). Only a few birds of prey and Siberian spruce grouse are rare and stocks of wood grouse can be small locally. Nature protection and conservation in taiga is aimed at the areas providing habitats for the typical forest mammals: brown bear, elk, lynx, otter, beaver, and sable.

The biome of larch forests, which are also known as the light taiga, and thin (sparse) forests occurs in Central and Eastern Siberia, in the Transbaikal region and in the Far East including the Sea of Okhotsk coast. Larch forests develop on permafrost on the lower slopes of mountains, where they alternate with mountainous thin forests and areas occupied by tundra vegetation, and penetrate far north along river valleys. The light taiga is characterized by the poorest species composition among all forest biomes. Its local floras contain not more than 400-450 vascular plant species, local mammal faunas are represented by 30-40 species, and avifaunas by 70-80 species (Amirkhanov, 1997). Exceptional are the fragments of cold relict steppes that often occupy southern slopes and river valleys including the Lena valley. There are no endemics and few rare and endangered species. The latter feature bighorn sheep and musk deer. Biological diversity is protected in Putoransky, Magadansky, and Olekminsky zapovedniks.

Table 24.3 illustrates the levels of human transformations of ecosystems.

The share of territory completely transformed by human activities

Table 24.3 The share of territory completely transformed by human activities

Apart from the fully transformed lands, large areas of tundra and taiga are in different stages of degradation or restoration. In the tundra, vast areas are damaged by the grazing of domesticated reindeer. Acid emissions have destroyed vegetation across extensive areas around the copper-nickel smelters of Norilsk (Taymyr peninsula) and Monchegorsk (Kola peninsula). The development of hydrocarbons and extraction of other non-renewable resources causes mechanical disturbance of surfaces, pollution and damage to vegetation in the tundra and taiga of the Kola peninsula, the European north-east, Tyumen region, and Taymyr. Annually, timber is harvested on over 10 000 km2 and vast forest areas suffer from fires, which are often caused by human activities (Yablokov et al., 1996). Although reforestation occurs on most of the damaged land, swamps widely develop in forest clearings.

Broad-leaved and mixed broad-leaved coniferous forests occur on the East European plain and in the southern Far East (Figure 10.1).

Natural zones of the middle belt of Northern Eurasia

Fig. 10.1 Natural zones of the middle belt of Northern Eurasia

Deciduous species prevail in the south and in the north coniferous species dominate with Pinus sylvestris, which occurs in dry habitats on sandy and stony soils, being widespread across the biome. This biome is characterized by a relatively high diversity of plant and animal species. The local flora contains up to 700-800 species, mammal fauna contains 50-60 species in the European territory and up to 70 in the Far East, and avifauna comprises 120-150 species (Amirkhanov, 1997). Endemism is not high but there are many rare species of plants, particularly in the Far East such as species of Cyprepedium, Trapa, and Panax ginseng. Among animals, the Amur tiger and leopard are rare. The Amur tiger has become a focus of national and international conservation efforts. Until recently its population has been drastically declining because of poaching. In 1997, a federal programme aimed specifically at the preservation of the Amur tiger was established. It has adopted an integrated approach to conservation of the species and involves the protection of habitats, establishment of specific educational programmes for gamekeepers, and prevention of illegal hunting and trade. At present, there are about 460 individuals which are not yet enough to secure the expansion of the Amur tiger population.

Forest-steppes and steppes cover vast areas in the south of the East European plain, West Siberian lowland, and intermountain depressions of southern Central Siberia, and the Transbaikal region (Figure 11.1).

Location of steppe, forest-steppe, and semi-desert zones

Fig. 11.1 Location of steppe, forest-steppe, and semi-desert zones

Although the landscapes are dominated by monotonous grasslands, biological diversity is very high. For example, in meadow steppes, local floras contain 900-1100 species of vascular plants. In dry and arid steppes, species-richness is lower, 600-700 and 400-500 species, respectively (Tishkov, 1995). The fauna is inferior to that of forests with local faunas including 40-50 mammal and 80-90 nesting bird species. Endemic plants include relicts which survived glacia-tions in limestone habitats. However, the overall level of endemism is not high.

Cultivation has had a very powerful impact on steppes. Arable fields occupy between 30 per cent and 80 per cent of the land, depending on location, while fertile black soils on watersheds are completely plowed up (Tishkov, 1996). The European steppes have been plowed up almost completely; about 80 per cent of steppes in the Krasnodar region are plowed up, while the steppe ecosystems of the Azov and Kuban plains have been totally transformed. Degradation of steppe soils, through nutrient depletion and loss of organic matter, is a serious problem. On average, over the last hundred years the humus content in soils of the European steppes has decreased by a factor of 1.5-2.0. Overexploitation has led to the development of erosion and increased salinity in soils over a considerable area. Many floodplain ecosystems have been destroyed and the interfluve steppes have been degraded through the construction of dams and reservoirs on rivers, such as the Volga, Don, and Dnieper.

The biodiversity of steppes and forest-steppes, especially in Europe, has long been experiencing progressive depletion (Mordkovich et al., 1997). Many species have become rare and endangered. The RedData Book (1988) for plants lists a number of species of Stipa, Centaurea, and Fritillaria, Adonis vernalis, Crambe tatarica, and Paeonia tenuifolia. Among vertebrates mottled polecat and some birds of prey are rare. With the original habitats being greatly reduced, steppe landscapes and species are in urgent need of conservation and restoration. At an experimental level, promising results in ecological restoration have been achieved in the protected areas in the Northern Caucasus (Dudar, 1978), the Ukraine (Tishkov 1993, 1996) and the forest-steppes of Central Russia (Danilov, 1993). However, practical restoration requires the establishment of a wide network of protected areas. There are already a number of nature reserves in the steppes of Russia, Kazakhstan, and the Ukraine but many more are needed.

Semi-desert and desert biomes occur on the Caspian and Kura-Araks lowlands, in piedmont plains of the Lesser Caucasus, in Kazakhstan, and the republics of Central Asia. Ecosystems of semi-deserts and deserts vary greatly. Woody plants and low shrubs prevail, especially those in the Haloxylon and Artemisia genera. In some areas, vegetation consists of perennial grasses, sedges, and ephemeral plants. Forests, composed ofPopulus tremula, Salix, and Elaeagnus, and meadows develop in river valleys and deltas. Local floras of zonal semi-desert and desert ecosystems contain 150-250 and 100-150 species respectively. Local mammal faunas contain 25-30 species and avifaunas 40-50 species. A distinguishing feature is a high diversity of reptiles with 25-30 species per 100 km2. Semi-desert and desert ecosystems have been traditionally used for cattle grazing and locally for haymaking and fuel wood collecting. More recently, irrigated agriculture has been developed with vast projects located in Central Asia, Kazakhstan, and Azerbaijan. The practices of contemporary agriculture and technological transformations have caused drastic changes in the arid environment and a great loss of biological diversity.

Much has been made of the Aral Sea crisis. However, in other areas of the arid zone (e.g., in Azerbaijan) moving sands, saline lands, and depleted pastures have replaced natural ecosystems. Much of the marginal land is undergoing intensive desertification. Seriously impacted by overgrazing is vegetation of the Kalmyk Republic and Astrakhan region of Russia (Babaev et al., 1986). Wind erosion is a severe problem in the steppes of Southern Siberia and northern Kazakhstan. This vast area, often referred to as the 'Virgin Lands', was ploughed up and harvested in just a few years in the late 1950s. Across the FSU, about 1.5 million km2 of agricultural land is saline, eroded lands occupy about 1.2 million km2, and waterlogging, induced by human activities, occurs on over 200 000 km2 (State Report, 1997).

Many mammal species (such as red deer inhabiting the ripirian forests of the Central Asian rivers, Persian gazelle, Central Asian ass, sand cat, Pallas's cat, Persian lynx, cheetah), birds (red kite, tawny eagle, peregrine falcon), and reptiles (desert monitor, sand viper) listed in the Red Data Book (1995) are arid zone species. A number of protected areas were established across the region under the Soviet regime: Tigrovaya Balka in Tajikistan; Amu-Daryinsky, Badkhyzsky, Krasno-vodsky, Repetek, Kugitangsky, Syunt-Sakhardagsky in Turkmenistan; Badai-Tugai, Zaaminsky, Kitabsky, and Kyzylkumsky in Uzbekistan. However, the achievements in conservation policy and practice have been set back in the republics of Central Asia despite the attempts of the international environmental community and funding provided by the Global Environmental Facility (GEF) and the World Wide Fund for Nature (WWF). Since 1990, data on the status of some rare animal populations in the region have been lacking. Fragile political structures, economic failures, outmigration of qualified personnel, growing population, and poverty pose a threat to conservation in these countries.

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