胶州湾滨海湿地土壤的盐渍化特征

目的]了解胶州湾滨海湿地土壤盐渍化特征,为胶州湾滨海湿地保护和区域土壤盐渍化防治提供科学依据。方法]在胶州湾选取芦苇、碱蓬、光滩及大米草4种典型滨海湿地分层采集土壤样品,通过测定土壤pH值、电导率和主要盐离子浓度开展研究。结果]胶州湾滨海湿地土壤盐分含量表现由低到高依次为:芦苇湿地碱蓬湿地光滩湿地大米草湿地,盐渍化类型呈现由滨海硫酸盐—氯化物型向氯化物盐渍化土类型过渡的特征;垂直方向上,大米草湿地和芦苇湿地具有表层积盐特征,碱蓬和光滩湿地则呈现出下层稍高趋势。除CO_3~(2-)(和HCO_3~-离子以外,胶州湾滨海湿地土壤主要盐离子含量均呈现出与全盐量、电导率一致的规律,主要盐离子浓度从高到低依次为:Cl~-Na~++K~+SO_4~(2-)Mg~(2+)HCO_3~-Ca~(2+)。结论]胶州湾滨海湿地土壤属于极重度盐化土,呈现自芦苇湿地向大米草湿地方向递增趋势;土壤碱度上属非碱化土,与土壤含盐量呈相反趋势,但植被易受苏打碱化土的潜在毒害作用。

Analysis on Characteristics of Soil Salinization in Coastal Wetlands of Jiaozhou Bay

Objective] The characteristics of soil salinization on the coastal wetland of Jiaozhou bay were studied to provide scientific basis for coastal wetland conservationof Jiaozhou bay and regional soil salinization prevention.Methods] Based on the tests of soil pH value, conductivity and main salt concentration of layered soil samples, four typical coastal wetlands of Jiaozhou bay including Phragmites australis wetland, Suaeda glauca wetland, the barren wetland and Spartina anglica wetland were sampled in August 2014.Results] The soil salt contents ranked as:Phragmites australis wetland < Suaeda glauca wetland < barren wetland < Spartina anglica wetland, the salinization type of the above transited from sulfate-chloride type to chloride salinization soil type. In terms of the vertical distribution, soil salinity were obviously accumulated at surface soil layer in Spartina anglica wetland and Phragmites australis wetland; while soil salinity was accumulated at deep soil layer in Suaeda glauca wetland and barren wetland. Except for CO₃^2- and HCO₃^-, other main salt ions contents in coastal wetland of Jiaozhou bay were consistent with total salt content and conductivity. Main salt ions contents in soil ranked as:Cl^- > Na⁺+K⁺ > SO₄^2- > Mg²⁺ > HCO₃^- > Ca²⁺.Conclusion] The coastal wetland soils of Jiaozhou bay had severe soil salination, and the soil salt content increased from Phragmites australis wetland to Spartina anglica wetland. The wetland soils in Jiaozhou bay was non-alkalized and the sample salt contents in it varied oppositely, whereby, the wetland plants were affected by the potential poisons of soda alkalized soil.