Composite constructed wetland for water eutrophication treatment

The invention discloses a composite constructed wetland for water eutrophication treatment. The composite constructed wetland comprises a vertical water inlet section, a horizontal geothermal section, a water insulation section and a horizontal ground section which are arranged on a geothermal layer; the vertical water inlet section is arranged at the left part, and the horizontal geothermal section, the water insulation section and the horizontal ground section are arranged at the right part from bottom to top; a steel slag layer, a volcanic rock layer, a zeolite layer and a gravel layer are sequentially laid on the vertical water inlet section from bottom to top; a steel slag layer, a volcanic rock layer and a zeolite layer are sequentially laid on the horizontal geothermal section from bottom to top; a lower water insulation layer, soil and an upper water insuation layer are sequentially arranged on the water insulation section from bottom to top; and a volcanic rock layer, a zeolite layer and a gravel lay