[Ichthyofauna and its community diversity in volcanic barrier lakes of Northeast China].

Based on the investigations of fish resources in Jingpo Lake and Wudalianchi Lakes in 2008-2011 and the historical data, this paper analyzed the characteristics of ichthyofauna and its community diversity in volcanic barrier lakes of Northeast China. The ichthyofauna in the volcanic barrier lakes of Northeast China was consisted of 64 native species, belonging to 47 genera, 16 families, and 9 orders, among which, one species was the second class National protected wild animal, four species were Chinese endemic species, and five species were Chinese vulnerable species. In the 64 recorded species, there were 44 species of Cypriniformes order and 37 species of Cyprinidae family dominated, respectively.

[Dynamics of CO2 and CH4 concentration in the mire soil and its impact factors].

The wetland plays a important role in global carbon cycling in terrestrial ecosystem, the greenhouse gas emission in the mire, especially the CO2 and CH4 level, show distinctly spatial and temporal variation. The product and emission of the CO2 and CH4 are related to soil organic carbon (SOC), dissolved organic carbon (DOC) and nitrogen content, meanwhile which are affected by the soil temperature and hydrological condition. The concentration of CO2 and CH4 are high in mire soil in the Sanjiang plain, especial at the root layer (10-35cm).

[The changes of the soil hydrothermal condition and the dynamics of C, N after the mire tillage].

The wetlands gain increasing attention to its crucial ecological and environmental function. The tillage of the mires in the Sanjiang Plain has played the important role in regulation of the region ecological balance and climate. Prior to tillage, the mean soil temperature of the topsoil (10 cm) in mire from June to September was 12.