Study On The Resistance Of Some Indoor Plants To The Compound Pollution Of Benzene And Formaldehyde

Indoor air pollution is the symbol of entering the third pollution period after soot pollution and photochemistry pollution.Among indoor air pollution,chemical pollution represented by formaldehyde and benzene is the most harmful,which seriously threatens public health and life safety,and has become the main problem of indoor environmental pollution.Indoor plants have a continuous and efficient purification effect on indoor chemical pollution due to their strong absorption,metabolism and degradation ability.Therefore,improving indoor chemical pollution by green plants has become an effective way and an important means to absorb,purify and remove indoor chemical pollutants.Indoor chemical pollution is basically a combination of several or even multiple pollutants,of which formaldehyde and benzene are the main pollutants.To this end,the nine indoor ornamental plants were used as experimental materials.Three repeated randomized block experiments were conducted on three plants polluted by different concentrations of formaldehyde and benzene by artificial fumigation.Starting from the response of symptoms and physiological and biochemical indicators,the changes of physiological and biochemical indicators of plants under combined pollution of formaldehyde and benzene were analyzed by variance analysis,multiple comparisons and membership function method,and the resistance of 9 indoor plants under combined pollution of formaldehyde and benzene was evaluated comprehensively.Screening of indoor ornamental plants with strong resistance lays a theoretical foundation for the study of plant optimization and ecological restoration of indoor compound pollution.Finally,considering the growth characteristics and ecological functions of indoor plants,following the principles of indoor plants,according to the environmental characteristics of different spaces in the room,the corresponding plant allocation model is put forward.The results show that:（1）Under the same concentration of combined pollution of formaldehyde and benzene,nine experimental plants showed different degrees of symptoms of injury,and their resistance to combined pollution of formaldehyde and benzene was different.Amongthem,thedamagesymptomsofMenthahaplocalyx,Impatiens balsamina,Melissa Officinali are obvious,the degree of damage is serious.They were most sensitive to the combined pollution of formaldehyde and benzene and had the weakest resistance.S.trifasciatavar.laurentiiand Kalanchoe blossfeldiana did not show obvious symptoms of injury,and had the strongest resistance to combined pollution of formaldehyde and benzene.（2）The changes of chlorophyll content（Chl）,malondialdehyde content（MDA）,soluble protein content,soluble sugar content,peroxidase activity（POD）,superoxide anion（O₂.^-）production rate in different plants were significantly affected by plant species,the concentration of formaldehyde and benzene,and the interaction between them.Moreover,the difference of the change rate of six physiological indexes in the experiment was more significantly affected by the different concentrations of formaldehyde and benzene.（3）Malondialdehyde content and soluble protein content,superoxide anion radical production rate and peroxidase activity increased in varying degrees with the increase of the combined pollution concentration of formaldehyde and benzene,while chlorophyll content and soluble sugar content decreased in varying degrees.（4）The resistance of 9 indoor plants to combined pollution of formaldehyde and benzene at different concentrations was evaluated by membership function.The results showed that the resistance of S.trifasciatavar.laurentii was the strongest among all the tested plants,followed by Kalanchoe blossfeldiana.Impatiens balsamina and Melissa Officinali had weak resistance to the combined pollution of formaldehyde and benzene.（5）According to the principle under the combined pollution of formaldehyde and benzene,and considering the ornamental value,growth characteristics and different ecological functions of plants comprehensively,the corresponding plant allocation model was put forward according to the different environmental characteristics of the doorway and porch,living room,bedroom,study,kitchen,toilet and balcony in the living room.