Study On Plant And Soil Ecological Stoichiometric Characteristics Of Salt Marsh Wetland In Inland Restoration

Wetland is a special ecosystem between land ecosystem and water ecosystem.In recent years,the research on wetland has become a research hotspot.The research on wetland biogeochemical cycle is the core content of wetland research.In this paper,the Reed and Scirpus salt marshes under different recovery years in Xianghai National Nature Reserve are taken as the research object,and the natural Reed and Scirpus salt marshes are taken as the reference to analyze the distribution characteristics of plant and soil nutrient content in the salt marshes under different recovery years in Xianghai National Nature Reserve,and to explore the distribution characteristics of eco chemical measurement of plants and soil in the inland salt marshes.In order to provide an important reference for vegetation restoration and ecosystem management and protection in salt marsh wetland,the correlation between eco chemical measurement of plant and soil was studied.Through the analysis and discussion of the experimental results,the main conclusions are as follows:(1)In Xianghai National Nature Reserve,the organic carbon content of Reed and Scirpus salt marsh plants is 448.34-463.27g/kg and 404.61-450.20g/kg,the total nitrogen content is6.18-17.94g/kg and 3.98-24.6g/kg,the total phosphorus content is 0.54-1.61g/kg and0.63-1.61g/kg,respectively.With the increase of recovery years,the organic carbon content,total nitrogen content and total phosphorus content of Reed and Scirpus are close to the natural state plants,and gradually surpass the natural state plants.In terms of plant organs,the organic carbon content,total nitrogen content and total phosphorus content of each organ in the salt marsh wetland of Xianghai National Nature Reserve from small to large are roots,stems and leaves.C /N of Reed and Scirpus in Xianghai National Nature Reserve decreased with the increase of recovery years,and C / P and N / P of Reed and Scirpus increased with the increase of recovery years.In terms of the average values of Reed and Scirpus in different growth stages,the change trend of C / N is July > September > May,the change trend of C / P is September > July > May,but the change trend of Reed N / P is September > May > July,and the change trend of Scirpus N/ P is May > September > July.Although the C / N,C / P and N / P of the two wetland plants in different growth stages are relatively complex,the ecostoichiometric ratio of the two dominant plants in the inland salt marsh is C/P>C/N>N/P.The N/P of root,stem and leaf of two dominant plants in Xianghai National Nature Reserve is less than 14,and the growth of plants in this study area is mainly limited by N.(2)The organic carbon content of Reed and Scirpus salt marsh soil in Xianghai National Nature Reserve is 3.60-16.61g/kg,3.94-14.33g/kg,total nitrogen content is 0.14-1.20g/kg,0.21-1.25g/kg,total phosphorus content is 0.11-0.22g/kg,0.13-0.29g/kg,respectively.With the increase of recovery years,the content of soil organic carbon,total nitrogen and total phosphorus in Reed and Scirpus salt marsh wetland in Xianghai National Nature Reserve is increasing,and the trend is approaching and surpassing that of natural salt marsh wetland.The content of organic carbon,total nitrogen and total phosphorus decreased with the deepening of soil layer.No matter in May,July or September in the early stage of plant growth,the soil C / N of Reed and Scirpus communities in salt marsh wetland of Xianghai National Nature Reserve decreased with the increase of recovery years;the soil C / P of Reed and Scirpus communities increased with the increase of recovery years and was close to the natural soil C / P;Reed and Scirpus communities The N / P of the falling soil increased with the increase of the recovery period and was close to that of the natural soil.(3)The content of organic carbon,total nitrogen and total phosphorus of Reed and Scirpus salt marsh plants in Xianghai National Nature Reserve is higher than that of soil.The correlation between Reed,Scirpus and soil ecostoichiometry C,N,P,C / N,C / P,N / P in salt marsh wetland of Xianghai National Nature Reserve gradually approached and exceeded that of natural wetland with the increase of recovery years,and the correlation between plants and soil was more significant(P<0.01).However,the correlation between Reed,Scirpus and soil ecostoichiometry C,N,P,C / N,C / P,N / P increased from the beginning to the end of growing season in Xianghai National Nature Reserve.