NaCl对辽河口湿地土壤溶解性有机碳吸附解吸的影响

NaCl Effect on Adsorption and Desorption of Dissolved Organic Carbon in Soils in Liaohe Estuary Wetland

以辽河口芦苇湿地0~40 cm深度土壤作为研究对象,采用平衡吸附法,研究了辽河口湿地土壤对不同浓度溶解性有机碳(DOC)的吸附解吸特征,并分析了不同深度土壤以及NaCl处理对DOC吸附解吸的影响。结果表明:辽河口湿地0~10 cm和10~20 cm深度土壤DOC吸附量随DOC浓度增大而下降;20~30 cm和30~40 cm深度土壤DOC吸附量随DOC浓度增大而上升。NaCl处理中,不同深度土壤DOC的可吸附量分别为0.038、0.044、0.021和0.011 g kg-1。除30~40 cm深度土壤外,DOC吸附量显著高于对照处理,且随DOC浓度的升高而增大,明显促进了辽河口湿地土壤对DOC的吸附。NaCl处理对辽河口湿地0~10 cm和10~20 cm深度土壤DOC的解吸量影响不显著,而对20~30 cm、30~40 cm深度土壤DOC的解吸量起到明显促进作用。

Soils at 0-40 cm depth in Liaohe estuary wetland were collected to study the adsorption and desorption characteristics of dissolved organic carbon（DOC） using equilibrium adsorption method.And the effects of different soil depths and NaCl treatment on DOC adsorption and desorption were analyzed.The result showed that the amount of DOC adsorption decreased at 0-10 cm and 10-20 cm soil depth and increased at 20-30 cm and 30-40 cm soil depth with DOC concentration increasing.In NaCl treatments,adsorption capacity of DOC at different depths was0.038 g kg^-1,0.044 g kg^-1,0.021 g kg^-1 and 0.011 g kg^-1,respectively.Except for soil at 30-40 cm depth,DOC adsorption was significantly higher in NaCl treatments than that in control treatment and it increased with DOC concentration increasing,which obviously promoted the adsorption of DOC to the soil of Liaohe estuary wetland.NaCl effect on DOC desorption capacity was not significant at 0-10 cm and 10-20 cm soil depth.However,NaCl had a significantly promote effect on DOC desorption capacity at 20-30 cm and 30-40 cm soil depth.