On the Coupling between Eddy Covariance and Remote Sensing Techniques in Ecosystem Carbon Flux Estimation

Abstract

Long term observation and research on carbon,water and heat fluxes of terrestrial ecosystem has been the global hotspot.To date,micrometeorology approach based on eddy covariance technique has been regarded as the only direct measurement of material and energy fluxes between atmosphere and biosphere,and has been the key technology of the international flux network.However,eddy covariance technique is a small scale observation method,and the results acquired from the method are difficult to directly scale up to larger scales.Moreover,the lack of observation data from regional,cross-scale ecosystems and their temporal-spatial dynamic remains an important issue limiting the progress of carbon cycle researches.With the development of remote sensing technology,it is possible to make the long term quantitative observation in large scale and high resolution ecosystems in the near future.These problems currently focus on how to establish the cross-scale observation system coupling carbon flux and remote sensing techniques,and how to link limited observation of carbon flux stations to large scale remotely sensed data and ecological models.The past works on coupling eddy covariance technique and remote sensing technology are summarized.The following three aspects were focused: ①Cross validation on the carbon flux estimation between eddy covariance and remote sensing technology;②Eddy covariance provides ground parameters for remote sensing inversion;③Remote sensing based eddy footprint analysis.Through discussion on these aspects and summary about their features and progress,it helps to sort out the ideas toward future work in this field.