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Bacteriophage is abundant in various aquatic environment. Napahai is a seasonal plateau wetland located in Yunnan of China. But the reports on phage abundance of Napahai have not been seen. The object of this study was to make an accurate estimation for phage abundance of Napahai. We collected water samples at different sampling sites in December 2013 and detected the abundance by epifluorescence microscopy using SYBR green I or SYBR Gold. The results indicate that the phage abundance of water samples in Napahai wetland ranged from 1.35 to 3.54×10 9 virus-like particles L -1 . The dying effect of SYBR Gold is better than SYBR green I. Phage abundance of Napahai is close to that of Yangtze River and higher than the Yunnan Plateau lake, Bita Lake (5×10 8 particles L -1 ) and largely lower than the polar lake Beaver Lake (2×10 10 particles L -1 ) (1).

Many results have showed that the great diversity of bacteriophages in various aquatic environments, including marine water, freshwater and paddy water, but few studies was about the genetic diversity of bacteriophages in the wetland. To better understand the genetic diversity of bacteriophages communities of Napahai wetland, we selected viral capsid protein gene (g23) as a gene marker to reveal genetic diversity of bacteriophage in Napahai wetland in Yunnan province of China. The g23 gene fragment of bacteriophage was amplified with the primers MZIA1Bis and MIZA6. In this study, 21 different clones fragments in g23 gene sequences were found. Phylogenetic analysis demonstrated that some g23 genotypes were closely related to the T4-like phages, the others clustered two groups were unknown sequences which had far evolutionary distances with the currently known phages sequences. So the unknown sequences may represent the new particular bacteriophage communities. Keywords-T4-type phage; Napahai wetland; g23 gene; Genetic diversity.

The numerical manifold method (NMM) is first proposed by Dr. Shi. The finite cover technology from the mathematical manifold analysis is incorporated into the NMM. Due to the independence of the mathematical cover system from the physical domain, the NMM has unique advantages on the analysis of both continuous and discontinuous problems. In the past decades, extensive effects have been put on the developments and applications of the NMM in different areas. In this paper, special attention was paid to the advances of the higher-order NMM.