Distribution and Accumulation of Soil Carbon in Temperate Wetland, Northeast China

Estimating carbon sequestration and nutrient accumulation rates in Northeast China are important to assess wetlands function as carbon sink buffering greenhouse gas increasing in North Asia. The objectives of this study were to estimate accreting rates of carbon and nutrients in typical temperate wetlands. Results indicated that average soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents were 37.81%, 1.59% and 0.08% in peatlands, 5.33%, 0.25% and 0.05% in marshes, 2.92%, 0.27% and 0.10% in marshy meadows, respectively. Chronologies reconstructed by Pb-210 in the present work were acceptable and reliable, and the average time to yield 0-40 cm depth sediment cores was 150 years. Average carbon sequestration rate (Carbon(sq)), nitrogen and phosphorus accumulation rates were 219.4 g C/(m(2).yr), 9.16 g N/(m(2).yr) and 0.46 g P/(m(2).yr) for peatland; 57.13 g C/(m(2).yr), 5.42 g N/(m(2).yr) and 2.16 g P/(m(2).yr) for marshy meadow; 78.35 g C/(m(2).yr), 8.70 g N/(m(2).yr) and 0.71 g P/(m(2).yr) for marshy; respectively. Positive relations existed between Carbon(sq) with nitrogen and precipitations, indicating that Carbon(sq) might be strengthened in future climate scenarios.