The delta of Volga river
The Volga Delta is the largest inland river delta in Europe. The Volga River
starts in the Valday Hills of northwestern Russia and flows 3,700km (2,300
miles) before creating this delta and pouring into the Caspian Sea. The delta
covers an area of 27,224km^2 and is approximately 160km across.
The Volga Delta is the largest inland river delta in Europe. The Volga River starts in the Valday Hills of northwestern Russia and flows 3,700km (2,300 miles) before creating this delta and pouring into the Caspian Sea. The delta covers an area of 27,224km^2 and is approximately 160km across.
The delta lies in the arid climate zone, characterized by very little rainfall - less than 3cm annually. Water entering the Volga delta separates into more than 500 channels, arms, and rivulets and spreads out onto the adjacent floodplain forming shallow lakes. These flows also carry many nutrients from upstream into the delta making it one of the world's most productive areas for fish, particularly sturgeon.
The delta also contains oil deposits where millennia of carbon-rich mud have piled until pressure and heat converted the organic material in the lowest layers into petroleum.
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The delta lies in the arid climate zone, characterized by very little rainfall - less than 3cm annually. Water entering the Volga delta separates into more than 500 channels, arms, and rivulets and spreads out onto the adjacent floodplain forming shallow lakes. These flows also carry many nutrients from upstream into the delta making it one of the world's most productive areas for fish, particularly sturgeon.
The delta also contains oil deposits where millennia of carbon-rich mud have piled until pressure and heat converted the organic material in the lowest layers into petroleum.
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Size:
86,000 sq. km (34,000 sq. miles)
Habitat type:
Large River Deltas
Geographic Location:
Western Asia: Kazakhstan and Russia
Conservation Status:
Critical/Endangered
86,000 sq. km (34,000 sq. miles)
Habitat type:
Large River Deltas
Geographic Location:
Western Asia: Kazakhstan and Russia
Conservation Status:
Critical/Endangered
Local Species
About 400 vertebrates, including 127 species of fish and 260 species of birds (including swans, ducks, herons, terns, and ibis), as well as 850 aquatic invertebrates, 430 different plants, and more than a thousand species of insects can be found in the delta.
Sturgeon species found in the delta are the Russian (Acipenser gueldenstaedti), Beluga (Huso huso), sterlet (A. ruthenus), and stellate (A. stellatus) sturgeons, in addition to migratory species such as whitefish (Salmonidae) and herrings (Clupeidae). White-eyed bream (Abramis sapa) and the endemic Volga lamprey (Caspiomyzon wagneri) are some of the rare fishes found in this ecoregion.
The ecoregion has the distinction of being named a Wetland of International Importance because it provides habitat for many migratory birds. Among the unusual birds found here are the Dalmatian pelican (Pelecanus crispus), great white egret (Egretta alba), and penduline tit (Remiz penduculinus).
About 400 vertebrates, including 127 species of fish and 260 species of birds (including swans, ducks, herons, terns, and ibis), as well as 850 aquatic invertebrates, 430 different plants, and more than a thousand species of insects can be found in the delta.
Sturgeon species found in the delta are the Russian (Acipenser gueldenstaedti), Beluga (Huso huso), sterlet (A. ruthenus), and stellate (A. stellatus) sturgeons, in addition to migratory species such as whitefish (Salmonidae) and herrings (Clupeidae). White-eyed bream (Abramis sapa) and the endemic Volga lamprey (Caspiomyzon wagneri) are some of the rare fishes found in this ecoregion.
The ecoregion has the distinction of being named a Wetland of International Importance because it provides habitat for many migratory birds. Among the unusual birds found here are the Dalmatian pelican (Pelecanus crispus), great white egret (Egretta alba), and penduline tit (Remiz penduculinus).
Featured species
White-eyed bream (Abramis sapa)
The Volga bream (spawning population) varies in length from 17-49cm and weighs 170- 2,060g. It inhabits 3 types of water bodies during its life span: rivers, delta-front of the Volga River, and shallow areas of the Caspian Sea. It spawns at the low floodplains during spring flood season and feeds in the delta-front and sea. The most abundant are populations in the Volga and Ural Rivers. Freshwater forms also exist as well.
The Volga bream occurs at feeding grounds of water salinity up to 14%. Its diet consists of mollusks, crustaceans, worms, Chironomidae, plants, sediment and insects. Eggs are deposited on aquatic plants as well as on drifting remains of aquatic vegetation. Due to their adhesive membrane, eggs stick to plants. Typical spawning sites are temporarily flooded water bodies, low-floodplains and lakes.
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The Volga bream (spawning population) varies in length from 17-49cm and weighs 170- 2,060g. It inhabits 3 types of water bodies during its life span: rivers, delta-front of the Volga River, and shallow areas of the Caspian Sea. It spawns at the low floodplains during spring flood season and feeds in the delta-front and sea. The most abundant are populations in the Volga and Ural Rivers. Freshwater forms also exist as well.
The Volga bream occurs at feeding grounds of water salinity up to 14%. Its diet consists of mollusks, crustaceans, worms, Chironomidae, plants, sediment and insects. Eggs are deposited on aquatic plants as well as on drifting remains of aquatic vegetation. Due to their adhesive membrane, eggs stick to plants. Typical spawning sites are temporarily flooded water bodies, low-floodplains and lakes.
Read more:
Threats
Dams upstream have altered the natural flow regime of the river thus negatively affecting the productivity of the delta and its fauna. Planned impoundments, water diversions, industrial, agricultural, and domestic pollution further threaten the health of populations dependent upon the delta ecosystem. Cyanobacterial blooms and deoxygentation have increased in recent years.
Dams upstream have altered the natural flow regime of the river thus negatively affecting the productivity of the delta and its fauna. Planned impoundments, water diversions, industrial, agricultural, and domestic pollution further threaten the health of populations dependent upon the delta ecosystem. Cyanobacterial blooms and deoxygentation have increased in recent years.
WWF´s work
In Russia, WWF is particularly working on securing the unique Russian network of natural protection areas, representing all of the most important types of nature in the country, including inter alia, lakes, rivers, delta, and coasts. In many places in Russia, the areas are threatened by huge political and financial changes.
WWF is trying to safeguard the areas by strengthening their importance for local society. In many poor agricultural areas, a protected nature area may help giving the area a special profile and identity and ensure international attention.
WWF has carried out a project in 3 reserves in western Russia: Nizhnersvirsky at the Ladoga Lake, the Bryansk forests at the border of Ukraine, and Okski at the head of the Volga river.
In Russia, WWF is particularly working on securing the unique Russian network of natural protection areas, representing all of the most important types of nature in the country, including inter alia, lakes, rivers, delta, and coasts. In many places in Russia, the areas are threatened by huge political and financial changes.
WWF is trying to safeguard the areas by strengthening their importance for local society. In many poor agricultural areas, a protected nature area may help giving the area a special profile and identity and ensure international attention.
WWF has carried out a project in 3 reserves in western Russia: Nizhnersvirsky at the Ladoga Lake, the Bryansk forests at the border of Ukraine, and Okski at the head of the Volga river.
ZDROJ:http://wwf.panda.org
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