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80 • "PROTIST—2016
from the headwaters to the mouth. The maximum development of the protists received at the mouth of Warm Creek. Here the number of protists in 50, and biomass 25 times higher than the average. Thus, the protists of a small river with significant agricultural load, have high species diversity. The trends of increasing species richness, abundance and biomass of protists from the source to the mouth of the watercourse.
THE PROTISTAN SPECIES MAXIMUM CONCEPT AND ITS IMPLICATIONS TO INVASIVE BIOLOGY Telesh I.V.
Zoological Institute RAS, St. Petersburg, Russia [email protected]
The paper discusses possible implications of the novel protistan species maximum concept for the predictive modelling of ecosystem resilience and vulnerability to alien species invasions. Recent development of the protistan species maximum concept for the challenging zone of critical salinity 5-8%o (horohalinicum), where macrozoobenthos experience destructive osmotic stress (Telesh et al., 2011), is presented. This concept arose from the discovery that not all brackish waters are poor in plankton species, which was exemplified by the Baltic Sea data. The concept has gradually evolved to the understanding that in the environment with sharp salinity fluctuations community regulations and life strategies of small unicellular planktonic organisms differ substantially from those of large multicellular bottom-dwellers. Special efforts were undertaken to define the major organismal traits and environmental factors responsible for this new peculiar biodiversity pattern. Phytoplankton cell size, seasonality in development, and water salinity were tested as key characteristics. A long-term (1972-2006) phytoplankton dataset from the Baltic Sea ("the sea of invaders") was analyzed by means of correlation analysis, non-metric multidimensional scaling, and rarefaction analysis. Results prove statistically that algal cell size minimum underpins the protistan species maximum in the horohalinicum. Seasonality in phytoplankton development promotes the shift in community composition towards dominance of the small-sized species in the critical salinity regions. The protistan species maximum in the horohalinicum is largely backed up by the significant between-sample variation in species richness in the highly changeable brackish-water environment. The work was funded in part by the Russian Foundation for Basic Research, project 15-29-02706.
PROFILING THE PROTOZOAN TAXONO-MIC AND FUNCTIONAL DIVERSITY OF AN ANTARCTIC DRY VALLEY Thompson A.R.1, Buelow H.2, Takachs-Vesbach C.2, Adams B.J.1
1 - Department ofBiology, Brigham Young University
2 - Department ofBiology, University of New Mexico [email protected]
The McMurdo Dry Valleys of Victoria Land Antarctica are some of the harshest terrestrial habitat on earth. At 78°S and 163°E, the average temperature of the region is <-20°C, precipitation is <10 cm yr -1 and the growing period during the austral summer lasts only a few months when the landscape is warmed enough for glacier-fed streams to flow and some permafrost to thaw. Life is almost entirely microbial in these valleys and the landscape is dominated by extremely dry soils that are highly saline, oligotrophic, basic in pH and subject to frequent freeze-thaw cycles. This system is a great outdoor laboratory as the extreme conditions have reduced complexity such that intricate interactions between soil taxa can be unraveled. Our research aims to investigate protozoan diversity in these valleys in order to understand fundamental aspects of protozoan ecology that can be applied broadly. However, our understanding of the taxonomic diversity, distribution and functional roles of these organisms in these valleys is still lacking. To begin to address this, a variety of soils were sampled from two valley systems and metagenome and transcriptome datasets were constructed using next generation sequencing. Our results so far suggest that there is greater taxonomic and functional diversity than was previously thought present, with relatively high representation from many major ciliate and cercozoan clades. Future sequencing efforts will undoubtedly shed more light on distribution and richness of individual OTUs.
MANY PREVIOUSLY INCERTAE SEDIS AMO-EBOZOANS FIND A HOME WITHIN THE CENTRAMOEBIDA
Tice A.K.12, Shadwick L.L.3, Spiegel F.W.3, Geisen S.4, Fiore-Donno A.M.4, Bonkowski M.4, Dumack K.4, Kang S.12, Brown M.W.12
1 - Department ofBiological Sciences, Mississippi State University, Mississippi State, MS, 39762
2 - Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS, 39762
3 - Department of Biological Sciences, University of Arkansas, Fayetteville, AR, 72701
4 - University of Cologne, Institute of Zoology,
