All-terrain subsurface flow constructed wetland combination system and application thereof

The invention belongs to the technical field of environmental engineering, and relates to a subsurface flow constructed wetland combination system and the application of the system. The constructed wetland combination system comprises three wetland units (16, 17 and 18), wherein the three wetland units respectively comprise wetland unit frames (13, 14 and 15), water distribution pipes (1, 3 and 5), water collecting pipes (2, 4 and 6), a water inlet pipe (19), connecting pipes (20 and 21), a water outlet valve (7), a vertical water outlet pipe (8) and a siphon (9), wherein the wetland units (16, 17 and 18) are connected with one another by the water collecting pipes (2, 4 and 6) or the water distribution pipes (1, 3 and 5), the wetland units (16, 17 and 18) are internally filled with substrates (10, 11 and 12), and the three wetland units are vertically distributed in a gradually-falling shape. The system and the application of the system provided by the invention have the advantages of being high in the adaptability to terrain, better in nitrogen and phosphorus removal effect for a water body, hard to block, convenient in operation, maintenance and management, low in project capital construction cost and running cost and the like.