Kara Sea large marine ecosystem
The Kara Sea large marine ecosystem (LME) is a high-latitude marine ecoregion located in the Polar Circle on the Siberian shelf. The rocky coasts are indented with many small bays and inlets and are covered in shrubs and moss. The LME is separated from the Laptev Sea LME by the Northern Land Islands. The shallow Kara Sea is seasonally ice-covered. Warm ocean currents flowing into this LME from the North Atlantic Ocean provide mostly ice-free conditions from May to October. The Yenisei, Taz, and Ob rivers are an important source of freshwater and nutrients.
The Kara Sea LME is characterized by the freshwater input of its three major rivers, and by water exchange with the Arctic Ocean. it has a high diversity of habitats. For more information on water circulation, sea levels, wind-driven currents and tides, see this IOC/UNESCO document. The Kara Sea LME is considered a Class III, low productivity, ecosystem based on SeaWiFS global primary productivity estimates. Seasonal ice covers the region during much of the year, which limits the availability of light and nutrients. Zooplankton biomass production is relatively low, and the distribution and species composition is influenced by the proximity of the Atlantic Ocean. The rivers bring large amounts of nutrients into the Kara Sea every year. For more information on the LME’s physical and biological systems and its response to climate change, see the Arctic Climate Impact Assessement (ACIA).
Fish and Fisheries
Figure 2. Kara Sea LME-1. (Source: NOAA)
The LME supports a diversity of wildlife. Bearded seals, walruses, and narwhals breed and rest on the coastal areas of the Kara Sea. The polar bears hunt for seals on the frozen edge of the sea. There is an abundance of fish such as Arctic cod, flatfish, and smelt. Data on fish landings of the most important fish species indicate a significant decline in landings of whitefish in four areas. This tendency is most evident in the western part of the Kara Sea LME. In the Ob Bay, the landings of whitefish declined by 42 % between 1990 and 1994. In the lower Yenisei river, the decline was 35 % during the same period. The recorded landings of whitefish from Ob Bay in 1994 were only 46 % of the landings recorded ten years earlier. The University of British Columbia Fisheries Center has detailed fish catch statistics for this LME.
Pollution and Ecosystem Health
The Kara Sea LME is impacted by a variety of anthropogenic contaminant sources. Oil and gas development and fisheries impacts pose severe threats to the region. Radioactive materials dumped into the Kara Sea LME may be severely impacting the ecosystem, resulting in the deaths of sea stars, shellfish, seals, porpoises and fishes. Before 1992, not much was known about radioactivity levels from dumping operations in the Arctic Seas. That picture has changed over the past three years, largely due to the joint efforts of scientists from Russia, Norway, and the IAEA's Marine Environment Laboratory in Monaco. The Siberian rivers discharging into the Kara Sea LME encompass industrial and agricultural regions within their watershed. In these industrial regions the air, water and soil are polluted by harmful substances. Obsolete technologies and the lack of facilities for processing industrial waste are major ecological problems. Contaminants can be found in regions that are a part of the watershed of these rivers. Some of the rivers are reportedly polluted with PCBs, DDT), heavy metals, and viral contaminants. The Ob River contains plutonium and iodine. Moving upstream toward nuclear processing facilities, there are levels of radionuclides. For more information on the environmental distribution of pollutants, on UV radiation and on climate change, see the Arctic Climate Impact Assessment (ACIA) web page.
Economic activity focuses on fisheries and the exploitation of natural resources (petroleum and natural gas). The earliest sedentary peoples of the area hunted caribou on the tundra, harpooned seals, walruses and beluga on the waters and ice of the Kara Sea, and caught white fish in rivers and lakes. About a 1,000 years ago, the Nenets moved into the area. They followed a nomadic lifestyle based on reindeer breeding, as did a number of Khanty who also settled in the region. In the early 1980s, Bovanenkovo and several other major gas fields were discovered in the Yamal Peninsula. This made the region a prime target for development. Given its immense potential, large numbers of non-native newcomers were drawn to the area. The natural gas reserves of two basins in the Kara Sea LME (Rusanovskoe and Leningradskoe) are estimated at 5 trillion cubic meters.
The Kara Sea LME is situated on the Northern coast of Russia. The diverse habitats and wildlife of this region can be found in the Franz-Josef Land Nature Reserve--the largest protected marine area in the Northern Hemisphere. When non-indigenous peoples moved into the area in great numbers following the oil boom, the native peoples, by now a small minority, were excluded from any meaningful participation in the political decision-making process. The indigenous reindeer breeders lost huge acreages of pasture land. In 1988, the Nenets responded to threats to their subsistence economy and cultural survival by forming an organization. This was meant to improve their economic and social conditions as well as strengthen their political autonomy. However, the political power of this organization is severely limited since the Nenets are not in a position to make major decisions over land and resource use. In any event, the indigenous residents are now too few to influence government policies. The breakup of the Soviet Union in 1991 led to a deterioration of the environment. Indigenous peoples appear to be paying the price for the short-term economic benefits that are being reaped from oil and gas resources.
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