| Summary: | 학위논문 (석사)-- 서울대학교 대학원 : 생명과학부, 2015. 2. Jonathan Adams. Little is known of the diversity, community structuring, niche differentiation and habitat specialization of small soil Metazoa in polar environments. Here, I studied three contrasting high arctic tundra types at Kongsford, NW Svalbard (78° 55 N), comparing the small soil Metazoa community in each along with the comparison to a mid-latitude temperate forest site in Korea (37 deg.N), using an identical interrupted grid sampling scheme. In addition, communities of nematode present in local microsites (rhizosphere, cyanobacterial mat, etc.) in the arctic tundra were also compared. Soil Metazoa, mostly nematodes were extracted using combined Baermann funnel and sugar flotation, and the DNA extracted, PCR amplified for the NF1-18Sr2b region of the 18s rRNA gene, and 454 pyrosequenced. Our samples revealed diverse communities of soil Metazoa in all three tundra types, with species proxy (operational taxonomic unit, [OTU]) diversity far exceeding the species diversity based on morphological surveys in previous studies of Svalbard. There was no difference in OTU α-diversity between the three tundra types. I found no correlation between nematode and soil properties but across individual samples there was a positive correlation between Shannon α-diversity with TOC, C/N ratio and P2O5. β-diversity was significantly higher in IV and LV tundra, suggesting that their mosaic of bare and vegetated patches supports a greater range of local metazoan communities than the more uniformly vegetated HV tundra. HV tundra had a distinct community from the LV tundra type, with the community of IV tundra falling between these in terms of OTU composition, indicating an important element of niche and habitat differentiation amongst small soil Metazoa between the three different tundra types. Different microsite types were differentiated at some degree based on NMDS resulted from Bray Curtis similarity matrix. The strongest differences were between rhizophere and cyanobacterial mat ...
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