大凌河口湿地水盐梯度下翅碱蓬的生态阈值

Ecological thresholds of Suadea heteroptera under gradients of soil salinity and moisture in Daling River estuarine wetland

基于大凌河口湿地翅碱蓬生物量、密度、株高、株重等生物指标之间极显著的相关性，选取生物量为指标，研究不同土壤理化因子条件下，翅碱蓬种群分布的变化规律。结果表明：翅碱蓬生物量自然对数分别与土壤盐分、水分含量之间具有极显著的一元二次曲线拟合关系，表明翅碱蓬群落分布受土壤水分、盐分的影响；用高斯模型求解出大凌河口湿地翅碱蓬随土壤水盐变化的生态阈值，翅碱蓬的最适土壤盐分为12.14 g·kg-1，生态阈值区间为5.02～19.26 g·kg-1，最适生态阈值区间为8.58～15.70 g·kg-1；翅碱蓬最适土壤水分为59.82%，生态阈值区间为22.02%～97.62%，最适生态阈值区间为40.92%～78.72%。上述研究结论为河口湿地翅碱莲生境保护与植被修复提供了科学依据。

Based on the significant correlation of biomass with density, height and weight of Suadea heteroptera, the biomass was selected as a biological index for analyzing the distribution pattern of S. heteroptera population under different soil physicochemical conditions. Quadratic nonlinear regression of the biomass of S. heteroptera to soil moisture and salinity was fitted very well, suggesting that the distribution of S. heteroptera population was affected by soil salinity and moisture. The ecological thresholds of soil moister and salinity for S. heteroptera in the Daling River estuary were analyzed by Gaussian Model. The results indicated that the optimum soil salinity for the growth of S. heteroptera was 12.14 g·kg-1, with the ecological threshold of 5.02-19.26 g·kg-1 and the optimum ecological threshold of 8.58-15.70 g·kg-1. The optimum soil moisture was 59.82% with the ecological threshold of 22.02%-97.62% and the optimum ecological threshold of 40.92%-78.72%. These results provided basic references for habitat protection and vegetation restoration of S. heteroptera in the estuarine wetland.