Development of alpine wetland vegetation and its effect on carbon sequestration after dam construction: A case study of Lashihai in the northwestern Yunnan plateau in China

The species composition and distribution, as well as the effect on carbon sequestration, was studied in newly formed alpine wetland established after dam construction in Lashihai on the northwestern Yunnan plateau in China. The plant species present, their distributions and aboveground biomass, and soil organic carbon were investigated. A submerged vegetation zone (SVZ), an emergent vegetation zone (EVZ) and a drawdown vegetation zone (DVZ) were observed along the flooding gradient from the lake towards the lakeshore five years after dam construction, on what was previously a meadow. The EVZ accounted for approximately 70% of the total zone width, and all plant species were previously recorded in Lashihai. The values of carbon storage in the vegetation were 57 ± 10 g C m−2, 112 ± 4 g C m−2, and 56 ± 3 g C m−2 in the SVZ, EVZ and DVZ, respectively. The values of soil carbon storage were 2234 ± 160 g C m−2, 2309 ± 85 g C m−2 and 1552 ± 102 g C m−2 in the SVZ, EVZ and DVZ, respectively. We concluded that the wetlands that formed following dam construction began to function as a carbon sink, and water depth was the driving force for the establishment and zonation of plant communities.