Spatial Distribution Of Forest Carbon Flux Based On FBEM Model

Forest ecosystems directly affect the cycling and transformation of carbon between the organic and inorganic worlds of the ecosystem.Quantitative research on the temporal and spatial differences of the carbon cycle of forest ecosystems is helpful to understand the response and feedback of forest carbon cycle to climate change.However,for a long time,the research on detailed analysis of the temporal and spatial distribution of forest carbon cycle has not been comprehensive.This study improves the FBEM model,uses environmental factor data-driven models collected by wireless sensors to estimate forest ecosystem carbon flux(NEE),and analyzes the spatial and temporal heterogeneity of carbon flux in the study area.The results indicated:(1)In this research process,there is a significant linear relationship between the NEE value estimated by the FBEM model and the verification value,and the NEE change trend is basically the same;the correlation between the improved FBEM model estimation result and the verification value has been significantly improved.It shows that the FBEM model is feasible in the field of carbon cycle monitoring.(2)During the monitoring period,the monthly average NEE of the experimental area increases with the change of the month,and the overall NEE is negative,which is carbon sink;the change of NEE in a single day is U-shaped;the time point of NEE positive and negative alternate is obvious Monthly variation characteristics.(3)The NEE in the canopy has obvious stratification,and the NEE increases with height.There is a delay phenomenon in the NEE value of the stratification in the canopy.In the case of large illuminance,the stratification in the canopy The percentage of NEE difference values is relatively stable.(4)In the canopy,each layer of GPP has a good linear correlation with the ambient temperature,and the correlation increases with height.This study explored the FBEM model in the study of the spatial and temporal differences of carbon cycle,and constructed a carbon cycle difference model in vertical space.The results show that the carbon cycle in the experimental area has obvious temporal and spatial heterogeneity.At the same time,based on the research results,the application system is developed to realize the visualization of environmental data and carbon flux.The improved model provided by this study is of great significance for the quantitative analysis of the spatial and temporal differences of carbon flux and its impact factors.