Artificial wet land and uses thereof

The invention provides a constructed wetland and the application thereof; wherein, the constructed wetland takes gravels and manganese sands as combined packing and can be used for treating wastewater in industries, such as iron and steel industry, etc., the wetland can reduce the nutrient content of organics, nitrogen, phosphorus, etc. in water, and meanwhile can remove metal ions, such as Fe, Mn, Cd, Pb, etc., more particularly, can reduce higher content of ions of Fe and Mn in iron and steel industry wastewater so that the index achieves the water quality standard of reclaimed water used as cooling water and the water intake quality requirement of reverse osmosis desalination process in Code for Engineering Design of Wastewater Reclamation and Reuse. The wetland has less engineering investment, simple management, low operation and maintenance cost, stable processing effect, so as to have better environmental, economic and social benefits. The wetland has better wastewater processing effect, stronger treatment capacity and stronger shock resistance loading capability, so the wetland can greatly solve the problem of excessively high concentration of Fe and Mn ions in wastewater reuse of the iron and steel industry, etc.