Experimental Study On Purification Of Sewage From Southern Emergent Aquatic Plant

The constructed wetland system has the advantages of economical economy and convenient implementation,and is one of the effective methods for controlling water pollution,especially urban sewage.The emergent plants are an important part of the wetland system.However,due to the climatic conditions,there are some differences in the species and growth status of the emergent plants in the north and south of China.Therefore,the dominant populations of the southern emergent plants are screened and targeted.Study on the mechanism and effect of purifying sewage can provide reference and basis for plant optimization and configuration for wetland restoration of polluted waters in the south.In this study,the outdoor greenhouse cultivation experiment using soilless hydroponics was carried out.By regularly monitoring the changes of total phosphorus,total nitrogen,ammonia nitrogen,chemical oxygen demand,plant physiological indexes and environmental temperature,the six types of emergent plants were compared.The purification mechanism and effect of four different concentrations of sewage showed that the removal effect of A.rugulosa and Reli flower was the best,and in practical application,the effect of A.rugulosa and Reli flower was better,and the ability to adapt to the environment was strong.It can be considered to use A.rugulosa and Reli flower as the first choice for purifying sewage plants.The specific research results are as follows:Total phosphorus:Abandoned bamboo has better removal effect on total phosphorus and water celery is the worst,and the sewage purification effect of different concentrations is ranked as T1<T2<T3<T4,so when the total phosphorus concentration in sewage is 1 mg/When L～2mg/L,it is more conducive to the absorption and purification of total phosphorus in the sewage by the emergent plants.Total nitrogen:Re-flowering has better effect on total nitrogen removal and water celery is the worst,and the sewage purification effect of different concentrations is ranked as T1<T2<T3<T4,so when the total nitrogen concentration in sewage is 15mg/L-25mg/When L is used,it is more conducive to the absorption and purification of total nitrogen in the sewage by the emergent plants.Ammonia nitrogen:Re-flower,A.arundinacea has better effect on ammonia nitrogen removal and water celery is the worst.And the sewage purification effect of different concentrations is ranked as T1<T2<T3<T4,so when the ammonia nitrogen concentration in the sewage is between 5mg/L～15mg/L,it is more conducive to the absorption and purification of ammonia nitrogen in the sewage by the emergent plants.Chemical oxygen demand:A.rugulosa has a better removal effect on chemical oxygen demand and water celery is the worst.And the sewage purification effect of different concentrations is ranked as T4<T1<T2<T3,so when the chemical oxygen demand concentration in the sewage is between 30mg/L～50mg/L,it is more conducive to the absorption and purification of chemical oxygen demand in the sewage by the emergent plants.effect.Among the six types of emergent plants,catalase activity,root activity and physiological characteristics refer to the equivalent indicators,and the growth of A.rugulosa and Reli flower is the largest,and the total phosphorus,total nitrogen,ammonia nitrogen and chemical oxygen demand are removed.The rate is proportional.This is mainly due to the development of the root system of A.sylvestris and A.sinensis,which has strong adaptability to the environment,and the developed root system is also beneficial to the life activities of microorganisms in the water body,thereby achieving the effect of purifying sewage.