黄河三角洲不同土地利用类型总铁分布特征及其影响因素

Distribution characteristics and influencing factors of total Fe content in different land use types in the Yellow River Delta.

铁元素是植物生长所必需的营养元素之一,对维持湿地生态系统稳定和湿地生态功能发挥具有重要的作用。本研究以黄河三角洲地区8种不同土地利用类型、7种植被群落类型为对象,分析了土壤中总Fe含量的空间分布特征及其影响因素。结果表明:黄河三角洲土壤总Fe含量均值为24.28 g·kg^(-1),其中,不同土地利用类型中,工矿区总Fe含量最高,为27.29 g·kg^(-1),森林湿地和光滩中总Fe含量最低,分别为22.55、22.56 g·kg^(-1);不同植物群落中芦苇覆盖下的土壤总Fe含量最高,为27.30 g·kg^(-1)。不同土地利用类型中的总Fe在0~10和10~20 cm深度的差异性显著(P<0.05);同一种土地利用类型在不同深度之间的差异性并不显著(P>0.05)。相关性分析表明,总Fe含量与有机质、总氮、铵态氮、碳酸氢根离子含量在每层均呈极显著正相关(P<0.01)。总Fe含量和分布还与成土母质、土壤类型、水文条件、氧化还原条件、人类活动等因素密切相关。

Iron is one of the essential nutrients for plants and plays an important role in maintaining wetland ecosystem stability and functioning.Here,we analyzed the spatial distribution and influencing factors of soil total Fe content across eight land use types and seven vegetation types in the Yellow River Delta.The results showed that the average content of total Fe in the soil was 24.28 g·kg^(-1).Among different land use types,the total Fe content was the highest in industrial and mining areas(27.29 g·kg^(-1))and lowest in forest wetland and bare land(22.55 and 22.56 g·kg^(-1),respectively).The maximum value of total Fe content occurred in the soils under the Phragmites australis community(27.30 g·kg^(-1)).There were significant differences in total Fe content at 0-10 and 10-20 cm depths across different land use types(P<0.05).There was no difference in total Fe content between different soil depths for the same land use type(P>0.05).The total Fe content was significantly positively correlated with soil organic matter,total nitrogen,ammonium nitrogen,and bicarbonate contents at each soil layer(P<0.01).The content and distribution of total Fe were also closely correlated with soil-forming parent material,soil type,hydrological and redox conditions,and human activities.