关键词：森林；陆地生态系统；碳循环；大气环流
摘 要：The overall objective of this research has been to develop the capacity to predict how future climatic variation may affect carbon cycle processes and net CO2 exchange with the atmosphere at the Howland Forest, a temperate-boreal ecotonal forest that uniquely represents this ecosystem type in the AmeriFlux network. Major goals of the project have been to (1) provide a detailed characterization of C-cycle processes at Howland; (2) develop and test prognostic models to forecast future C-cycle processes; and (3) obtain defensible estimates of the uncertainties in measured and modeled C fluxes and pools.