The Influence of the Baikalsk Pulp and Paper Mill (BPPM) on Baikal plankton: A Comparative Study of Phytoplankton and Zooplankton Responses to BPPM Purified Waste Water in 2005-2006
Svetlana V. Shimaraeva1, Michael F. Meyer2, Lyubov R. Izmestyeva1, Lyudmila S. Krashchuk1, Helene V. Pislegina1, Eugene A. Silow1*
1Institute of Biology of Irkutsk State University, Irkutsk-3, POBox 24, 664003, Russian Federation.
2School of the Environment at Washington State University, Pullman, WA 99164- 2812, USA.
In general, our research sought to disentangle differences in phytoplankton community composition and structure near areas of high pollution in relation to relatively pristine locations. For this, we compared an area near the south-eastern shore of Lake Baikal, where purified waste water from the Baikalsk Pulp and Paper Mill (BPPM) enters Lake Baikal relative to a pristine area (Point #1), located at a remote location on the Western shore of Lake Baikal. Phytoplankton communities at Point #1 were generally characterized by higher biodiversity, although functional diversity was relatively similar between the two locations. The lack of markedly different community compositions may be a production of peculiarities to the time of sampling. In 2005, zooplankton communities at both locations were anomalously high with respect to diversity and biomass, exceeding four times the average long-term observations from 1981 to 2003. Community composition was unusual, in that the consistently dominant Epischura baikalensis occupied a smaller proportion of present species, whereas rotifers and cosmopolitan cladocerans exceeded long-term averages. In contrast, 2006 was characterized by having anomalously low zooplankton abundance at both polluted and pristine locations. In 2006, E. baikalensis returned as the dominant present taxon; however, there were no significant differences between locations. We suggest that the lack of a significant difference implies a trophic equilibrium within phytoplankton and zooplankton communities in the southern area of Lake Baikal.
Key words: Lake Baikal, zooplankton, phytoplankton, human influence.