Soil carbon, nitrogen, and phosphorus stoichiometry of three dominant plant communities distributed along a small-scale elevation gradient in the East Dongting Lake

• Published in: Physics and chemistry of the earth. Parts A/B/C 2018-02, Vol.103, p.28-34
• Main Authors: Hu, Cong, Li, Feng, Xie, Yong-hong, Deng, Zheng-miao, Chen, Xin-sheng
• Format: Article
• Language: English
• Subjects: Dongting Lake wetlands; Elevation; Soil C, N, and P stoichiometry; Soil moisture
• ISSN: 1474-7065; 1873-5193
• DOI: 10.1016/j.pce.2017.04.001

Soil carbon (C), nitrogen (N), and phosphorus (P) stoichiometry greatly affects plant community succession and structure. However, few studies have examined the soil stoichiometric changes in different vegetation communities of freshwater wetland ecosystems along an elevation gradient distribution. In the present study, soil nutrient concentrations (C, N, and P), soil stoichiometry (C:N, C:P, and N:P ratios), and other soil physicochemical characteristics were measured and analyzed in 62 soil samples collected from three dominant plant communities (Carex brevicuspis, Artemisia selengensis, and Miscanthus sacchariflorus) in the East Dongting Lake wetlands. The concentration ranges of soil organic carbon (SOC), total soil nitrogen (TN), and total soil phosphorus (TP) were 9.42–45.97 g/kg, 1.09–5.50 g/kg, and 0.60–1.70 g/kg, respectively. SOC and TN concentrations were the highest in soil from the C. brevicuspis community (27.48 g/kg and 2.78 g/kg, respectively) and the lowest in soil from the A. selengensis community (17.97 g/kg and 1.71 g/kg, respectively). However, the highest and lowest TP concentrations were detected in soil from the A. selengensis (1.03 g/kg) and M. sacchariflorus (0.89 g/kg) communities, respectively, and the C:N ratios were the highest and lowest in soil from the M. sacchariflorus (12.72) and A. selengensis (12.01) communities, respectively. C:P and N:P ratios were the highest in soil from the C. brevicuspis community (72.77 and 6.46, respectively) and the lowest in soil from the A. selengensis community (45.52 and 3.76, respectively). Correlation analyses confirmed that SOC concentrations were positively correlated with TN and TP, and C:N and N:P ratios were positively correlated with C:P. These data indicated that soil C, N, and P stoichiometry differed significantly among different plant communities and that these differences might be accounted for by variations in the hydrological conditions of the three communities. •Soil C, N, and P stoichiometric characteristics changed significantly among different plant communities.•The dominate plant communities were limited by N in the Dongting Lake wetland.•Plant communities and hydrologic regime significantly influenced the soil stoichiometry in the East Dongting Lake.