湿地土壤不同水埋深度的剖面特征——以东洞庭湖为例
Soil profile characteristics in wetland at different submerging depths: A case study of the East Dongting Lake
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摘要: 以东洞庭湖湿地为研究对象,研究东洞庭湖湿地各类土壤的发育情况、剖面特征、理化性质以及养分的空间分布随地下水埋深度的增加而变化的规律。结果表明:1)随地下水埋深度的加深,土壤发育加深,表下层厚度增加,潜育层加深,土壤类型分布为草甸土—潮土。2)土壤的土粒密度大,平均值为2.78 g/ cm3,土壤密度变化范围为0.71 ~1.41 g/ cm3 。3)土壤有机质质量分数范围为1.78% ~5.07%,土壤表层有机质质量分数的分布规律随水埋深度的加深而减小,表下层土壤的有机质质量分数基本一致,在垂直方向上有机质质量分数随土壤剖面深度的增加而降低。4)土壤全P 的质量分数随水埋深度的增加而增加,在垂直方向上表层土壤的全P质量分数高于下层土壤;土壤全K 质量分数较高,随着水埋深度的加深而减小,在垂直方向上全K质量分数没有显著变化。5)土壤中Ca、Mg 元素随着水埋深度的变化没有规律性,其中水埋深度最浅的草甸土Ca、Mg 元素质量分数最高,其他样点剖面差异不大。Abstract: We studied soil profile characteristics, physico-chemical properties and nutrient distribution in wetland at different submerging depths in water of East Dongting Lake, central China. Results showed:1) The thickness of subsurface horizon and the depth of gley horizon increased as the wetland elevation increased,with soil types distributed as meadow soil and tidal soil. 2) The average soil particle density was 2.78 g/ cm3 and the soil bulk density varied between 0.71 1.41 g/ cm3. 3) The content of organic matters ranged from 1.78% to 5.07%. It decreased with the increase of soil depth. No change of organic matter content was found in subsurface horizon. 4) With the increase of wetland elevation, soil total P increased, but total K decreased. Total P in surface horizon were higher than that in subsurface horizon, but there were no significaut differences of total K between surface horizon and subsurface horizon. 5) The contents of Ca and Mg in gleyed meadow soil were higher than that in the other soil types, but there were no relationships between the depth of ground water and the conteuts of Ca and Mg.