TASS, December 28. The survey of consequences from the fuel spill at a power plant in Norilsk showed that the accident had affected plants in watersheds of one brook and two rivers. The Ambarnaya River suffered most of all, the Great Norilsk Expedition, organized by Russia’s Academy of Sciences’ Siberian Branch, said in its final report.

“The fuel spill has affected only the vegetation in floodplains of Bezymyannyi Brook and the Daldykan and the Ambarnaya rivers. The biggest impact was evident in the floodplain of the Ambarnaya River, which can be explained by its much bigger area and the higher diversity of vegetation communities, affected by petroleum products. There, the species diversity of vegetation communities has shrunk by three times: before the accident, there were about 9 species per 1 background community, and after it – 3 per 1 similarly affected community, while the general cover of plants has shrunk by 2.8 times – from 70% to 25%,” the report reads.

As for the floodplain of Bezymyannyi Brook, its species diversity at affected areas has shrunk by 2.8 times – from 11 species to 4, and the projective cover has shrunk by 2.2 times – from 53% to 24%. In the Daldykan River’s floodplain the species diversity has dropped by 1.7 times and the projective cover – by 1.5 times.

“In the Daldykan River, specialists have observed only one stage of the destructive process, which, probably, may be explained by the fact that by the time of the spill the brook’s waters were high, and most vegetation communities remained covered with spring waters,” the report reads. “At the same time, in the area of contact with the petroleum products there were a few small areas of shallow water with dispersed vegetation, which were not covered by the brook’s high waters.”

The biggest impact from the petroleum products on plants and vegetation was registered in the areas, which the water covered only partially, scientists said. Water plants and communities, which remained under the water, did not suffer or suffered much less. A strong impact was caused to the floodplain communities.

Experts say, certain damage to the species diversity was seen in the midstream of the Pyasina River, while in its mouth the species diversity is above the background levels. Besides, surveys of mosses showed that their biggest amounts were in the sources of the Pyasina River. In the river’s conditionally contaminated areas, their numbers are twice higher than the background levels, which points indirectly to an absence of contamination with petroleum products, not dissolved in water. Generally speaking, the communities’ diversity has not been affected by the spill, and a partial degradation was observed in five communities, the report reads.

Expedition to Taimyr

The Siberian Branch of the Russian Academy of Sciences for the first time over recent years has sent to the Taimyr Peninsula, at the invitation of Nornickel, a big scientific expedition to conduct a large-scale survey of the area. Scientists will use the expedition’s results to present nature-friendly solutions and suggestions for industrial companies, working in the Arctic.

The expedition’s key points were watersheds of the Rivers Pyasina, Norilka and Ambarnaya and Lake Pyasino. In August, experts from 14 research institutes of the Academy of Sciences’ Siberian Branch collected samples of soils, plants and sediments and later began tests at the institutes’ labs.