3.Along the water level gradient from the edge to the center of the dishing billabong, the concentrations of sulfur after 450d decomposition were 0.588g·kg -1 ,0.508g·kg -1 ,0.404g·kg -1 ,0.359g·kg -1 and 0.306g·kg -1 respectively, smaller than its initial concentration.
kg-1和0.306g. kg-1,均低于初始浓度,且沿着洼地边沿向中心依次降低.