黄河口新生湿地土壤中各形态硫的分布特征及其影响因素

Distribution Characteristics of Sulfur Forms and Its Affecting Factors in Soils of the Newly Created Wetland in the Yellow River Estuary

2020年9月,在今黄河入海口北部的新生潮滩区内,在碱蓬(Suaeda salsa)盐沼和柽柳(Tamarix chinensis)盐沼设置采样地,采集不同深度的土壤样品,对比了不同采样地土壤全硫、总无机硫以及各形态无机硫(水溶性硫、吸附性硫、盐酸可溶性硫、盐酸挥发性硫)的分布特征及其影响因素。研究结果表明,碱蓬盐沼和柽柳盐沼0~60 cm深度土壤全硫含量变化在804.96~881.50 mg/kg之间,在中国湿地土壤硫含量整体处于中等水平,大于世界土壤平均硫含量(700 mg/kg);碱蓬盐沼和柽柳盐沼土壤的全硫含量相近,且都在深层(30~60 cm)土壤中含量较大;碱蓬盐沼和柽柳盐沼土壤中总无机硫含量占全硫含量的比例都较大,其值分别变化在24.02%~42.94%和17.53%~29.22%之间;碱蓬盐沼土壤的总无机硫储量约为柽柳盐沼的1.6倍,前者具有较高的供硫水平;碱蓬盐沼土壤中的水溶性硫、吸附性硫和盐酸可溶性硫含量整体都大于柽柳盐沼,盐酸挥发性硫含量则在柽柳盐沼土壤中较大;在垂直方向上,碱蓬盐沼土壤的水溶性硫含量以及碱蓬盐沼和柽柳盐沼土壤中盐酸可溶性硫含量都在浅土层(0~30 cm)较大,而其他形态无机硫含量则在深土层较大;碱蓬盐沼土壤中不同形态硫的分布主要受土壤颗粒组成和土壤有机碳含量影响,而在柽柳盐沼中主要受土壤有机碳含量和氮养分含量影响。

In September 2020, the sampling sites were set up in the Suaeda salsa saltmarsh and Tamarix chinensis saltmarsh in the newly created marsh of the northern Yellow River estuary, and the soil samples were collected from different depths to compare the distributions characteristics of total sulfur, total inorganic sulfur and inorganic sulfur forms(H2O-S, Adsorbed-S, HCl-Soluble-S, HCl-Volatile-S) in soils and identify their key affecting factors. The results showed that the total sulfur contents in soils(0-60 cm) of Suaeda salsa saltmarsh and Tamarix chinensis saltmarsh ranged from 804.96 mg/kg to 881.50 mg/kg, with a moderate level across the marsh soils in China. However, the values were much higher than the average content of total sulfur in soils of world(700 mg/kg). The total sulfur contents in soils of Suaeda salsa saltmarsh and Tamarix chinensis saltmarsh were approximated and their higher values generally occurred in deep soil layers(30-60 cm). The proportions of total inorganic sulfur in total sulfur in soils of Suaeda salsa saltmarsh and Tamarix chinensis saltmarsh were generally high and the values varied between 24.02% and 42.94% and from 17.53% to29.22%, respectively. The stock of total inorganic sulfur in soil of Suaeda salsa saltmarsh was 1.6 times of Tamarix chinensis saltmarsh and the former showed higher sulfur supply capacity. The contents of H2O-S,Adsorbed-S and HCl-Soluble-S in soils of Suaeda salsa saltmarsh were much higher than those of Tamarix chinensis saltmarsh as a whole, while the values of HCl-Volatile-S in soils of Tamarix chinensis saltmarsh were much higher than those of Suaeda salsa saltmarsh. In the vertical direction, the contents of H2O-S in soils of Suaeda salsa saltmarsh and the values of HCl-Soluble-S in soils of Suaeda salsa saltmarsh and Tamarix chinensis saltmarsh were generally high in shallow soil layers(0-30 cm), while the levels of other inorganic sulfur forms were generally high in deep soil layers. The distributions of sulfur forms in soils of Suaeda salsa saltmarsh were mainly depended on soil grain composition and soil organic carbon, while those of Tamarix chinensis saltmarsh were primarily controlled by soil organic carbon and nitrogen nutrient.