ABSTRACT

SSuaeda salsa is an annual euhalophyte in estuarine wetlands. Soil properties of wetlands have an important influence on S. salsa growth. Therefore, the soil ecological thresholds is valuable for the restoration of degraded S. salsa wetlands. The objectives of this present study were to analyze the soil physicochemical properties and evaluate the soil ecological thresholds in the typical degraded areas for S. salsa growth. Soil text components became coarser with increased sand contents and less clay contents, as the higher degree of wetland degradation. Meanwhile, the salt contents in different soil depths gradually increased with the increased degree of degradation of wetlands. Evident changes in soil water content, organic matter content, and cations concentrations were not observed, while the concentrations of these factors were higher in the soil layer of 0–10 cm than those in the 20–30 cm. The soil pH in the 0–10 cm soil layer was lower than that in the 20–30 cm. The content of the three available nutrients did not change evidently with the increasing degree of degradation. The optimum thresholds of soil salinity and water content were 7.073–16.613 g/kg and 31.8–63.2%, respectively. 

摘要

南芥辣酱是河口湿地的一年生真盐生植物。湿地的土壤性质对莎莎的生长有重要影响。因此，土壤生态阈值对于退化的莎莎湿地的恢复具有重要意义。本研究的目的是分析土壤理化性质并评估典型退化地区的 S. salsa 生长的土壤生态阈值。随着湿地退化程度的提高，土壤文本成分随着沙子含量的增加和粘土含量的减少而变得更粗糙。同时，随着湿地退化程度的增加，不同土壤深度的盐分含量逐渐增加。没有观察到土壤含水量、有机质含量和阳离子浓度的明显变化，而这些因子在0~10 cm土层中的浓度高于20~30 cm土层。0~10 cm土层土壤pH低于20~30 cm。随着降解程度的增加，三种有效养分的含量没有明显变化。土壤盐分和含水量的最佳阈值分别为7.073-16.613 g/kg和31.8-63.2%。