Experimental Study On The Effect Of Simulated Acid Rain On The Decomposition Of Leaf Litter

In today's era,the economy is developing rapidly,society is constantly improving,and the scope of global acid deposition is also expanding.Acid deposition has seriously affected human production and life,and also affected the decomposition of litter in the ecosystem,which in turn affects the balance of the ecosystem.Litter and its decomposition play a very important role in maintaining the balance of nutrients in the ecosystem.Therefore,the issue of the impact of acid deposition on the decomposition process of litter has attracted the attention of many scholars.Therefore,this study combined the methods of field sample collection,outdoor temperature change cultivation and indoor analysis to analyze the decomposition characteristics and nutrient release processes of five leaf litters of heather,Chinese pine,black locust,arborvitae and willow under different types of acid rain A study was conducted to analyze the effects of acid rain type,rainfall frequency and decomposition medium on the litter decomposition characteristics and nutrient release.The main conclusions drawn by the institute are as follows:(1)The mass residue and decomposition rate constant k of different leaf litters are affected by the type of acid rain.Sulfuric acid rain treatment inhibited the decomposition of P.serrulate,P.tabulaeformis,R.pseuduacacia,P.orientalis and Populus leaf litter.Nitric acid rain treatment inhibited the decomposition of P.serrulate and P.tabulaeformis leaf litter.And the mixed acid rain treatment also inhibited the decomposition of these five leaf litters.(2)The influence of acid rain type on different nutrients of litter varies according to the type of litter.Sulphuric acid rain treatment inhibited the decomposition of C,N and P in the litter of P.serrulate.And it also inhibited the decomposition of C,N,P and K in the litter of P.tabulaeformis and R.pseudoacacia.In addition,it also inhibited the decomposition of N and P in the litter of P.orientalis and the decomposition of C and N in the Populus litter.Nitric acid and mixed acid rain treatments inhibited the decomposition of N and P in five leaf litters.(3)Different acid rain types have increased rainfall frequency and decomposition constant k has increased.The increase of precipitation frequency promotes the decomposition of leaf litter,the degree of which depends on the type of acid rain and the type of litter.(4)The effect of acid rain type on the release of different nutrients and the frequency of rainfall and the type of litter.These changes are related to the types of litter and nutrient elements.After 13 months of decomposition,after the frequency of precipitation increased,the sulfuric acid-type acid rain treatment suppressed the decomposition of N and K in the P.serrulate leaf litter,and also inhibited the C,N,P,and K in litter of P.tabulaeformis and P.orientalis decomposition,in addition to inhibiting the decomposition of C,N and P in the leaf litter of R.pseudoacacia and Populus.Nitric acid-type acid rain treatment promoted the decomposition of C and N in P.serrulate leaf litter,and also promoted the decomposition of C,N and P in P.tabulaeformis leaf litter.In addition,it also promoted the decomposition of C,N,P and K in the leaf litter of R.pseudoacacia and Populus.(5)The effect of decomposition medium on the residual rate of different leaf litter quality depends on the type of acid rain and the frequency of rainfall.During low-frequency precipitation,the sand medium suppressed the residual quality of the R.pseuduacacia,P.orientalis and Populus leaf litter under sulfuric acid acid rain treatment.During high frequency precipitation,the sand decomposition medium promoted the quality residual rate of nitrate acid rain treatment of P.tabulaeformis leaf litter,and the quality residual of leaf litter under mixed acid rain treatment of P.tabulaeformis and P.orientalis.Regardless of the frequency of precipitation,the decomposition constant k of the sand decomposition medium is reduced compared to the soil medium,which suppresses the decomposition of leaf litter.(6)The decomposition medium in litter decomposition affects the release of nutrients,and is related to the type of acid rain,the type of litter and nutrient elements.After 13 months of low-frequency precipitation,the sulfuric acid acid rain treatment in the sand medium inhibited the decomposition of C and N in the leaf litter of R.pseudoacacia and P.orientalis and the decomposition of C,N and P in the Populus leaf litter.The nitric acid rain treatment in the sand medium inhibited the decomposition of K in the leaf litter of P.tabulaeformis and the decomposition of C,N,P and K in the leaf litter of R.pseudoacacia,P.orientalis and Populus.The mixed acid rain treatment in the sand medium inhibited the decomposition of C,N,P and K in the leaf litter of R.pseudoacacia.During high-frequency precipitation,the sulfuric acid-type acid rain treatment in the sand medium inhibited the decomposition of C in the litter of P.serrulate leaves,the decomposition of P in the Populus leaves and the decomposition of N and P in the leaves of R.pseudoacacia.The nitric acid rain treatment in the sand medium inhibited the decomposition of nutrients in the litter of P.serrulate,R.pseuduacacia and Populus.The mixed acid rain treatment of the sand medium inhibited the decomposition of P in P.tabulaeformis leaf litter,the decomposition of C and P in the P.serrulate leaf litter,and the decomposition of various nutrients in Populus leaf litter.