The role of net ecosystem productivity and of inventories in climate change research:the need for “net ecosystem productivity with harvest”,NEPH

摘要

Background:There is an urgent need for quantifying the terrestrial carbon sink in the context of global carbon emissions.However,neither the flux measurements,nor the national wood balances fulfil this purpose.In this discussion article we point at various shortcomings and necessary improvements of these approaches in order to achieve a true quantification of the carbon exchange of land surfaces.Results:We discuss the necessity of incorporating all lateral fluxes,but mainly the export of biomass by harvest,into the flux balance and to recognize feedbacks between management and fluxes to make flux measurements compatible with inventories.At the same time,we discuss the necessity that national reports of wood use need to fully recognize the use of wood for energy use.Both approaches of establishing an ecosystem carbon balance,fluxes and inventories,have shortcomings.Conclusions:Including harvest and feedbacks by management appears to be the main requirement for the flux approach.A better quantification of wood use for bioenergy seems a real need for integrating the national wood balances into the global carbon cycle.