Abstract1_23 (Hasumi)

Hasumi, M., T. Hongorzul, and K. Terbish: Animal species diversity at a land-water ecotone in Mongolia. Limnology (Japan, International) 12(1): 37-45, April 2011. doi: 10.1007/s10201-010-0319-z ReadCube

Abstract: The biodiversity of wetland ecosystems has received scant attention in Mongolia. We measured amphibian and macroinvertebrate species diversity at a complicated land-water ecotone of a pond within a wetland complex in Shaamar during July 2005. From our study area (0.5-ha grassland and an adjacent pond), we sampled 4,926 animals including 1 mammal, 4 amphibian, and 26 aquatic macroinvertebrate (>2 mm) species with a biomass of 4,444 g. Among these, a backswimmer (Notonectidae sp. 1) was a dominant species, representing 65% of the total number of animals collected (3,209) and 22% of the mass (999 g). Our study area was small but contained 4 amphibian species (Hyla japonica, Rana amurensis, Bufo raddei, and Salamandrella keyserlingii) in a mixed community with Shannon Diversity Index (H') of 1.678 and Pielou's Evenness Index (J') of 1.211. No larvae or tadpoles of any amphibian species were found in the pond, indicating their early metamorphosis. H' and J' with 26 macroinvertebrate species were estimated to be 1.828 and 0.561, respectively. This suggests that low macroinvertebrate species diversity relative to high species richness is due to low evenness resulting from considerable numbers of a backswimmer. In 6 sites sampled in the pond, mean water pH revealed high alkalinity (range 9.01-10.45). The presence of our taxa in a highly alkaline environment indicates that they may be alkaliphilic.