Abstract: A high diversity of psychrophilic and psychrotolerant bacteria have been identified in Tibetan Plateau lakes. Isolating pure strains of these bacteria can provide us essential knowledge on the mechanism of coldadaptation. However, it has always been a technical obstruct on how to transport these precious samples from the field to laboratories without reducing bacterial viability. Here, the influence of water sample preservation methods on the bacterial viability was investigated. We first isolated pure bacterial strains from water samples cryopreserved at -80  ℃ and fridgestored at 4  ℃, and classified these bacteria based on their 16S rRNA gene sequences. Seven unique 16S operational taxonomic units (OTUs) were recovered from the water samples stored at -80  ℃, which were identified asBacillus sp. D-U164(2010), Bacillus simplex, Exiguobacterium sp. Mkj28, Bacillus muralis, Acinetobactersp. L-HG-2BW, Exiguobacterium sp. AC-CS-C2, and Bacillus thuringiensis, respectively. In contrast, 14 OTUs were recovered from the water samples stored at 4  ℃, and were classified as Proteobacterium M71 D72, Chryseobacterium sp. 12 4K, Bacillus sp.HJ14, Bacillus pumilus, Stenotrophomonas sp. LL75,Bacillus muralis, Bacillus cereus, Brevundimonas bullata, Stenotrophomonas sp. Cza24, Microbacteriumsp. VKM Ac2016, Stenotrophomonassp. Ala15, Bacillussp. T4(2013), respectively. Our results indicated that higher diversity of culturable bacteria was recovered from fridgestored water samples than that of cryopreserved. Bacillussp. can be isolated from water samples cryopreserved at -80  ℃ and fridgestored at 4  ℃.

Key words: landscape connectivity, Presbytis leucocephalus., ecological corridor, least-cost path