Ecosystem models have not comprehensively considered how interactions among fire disturbance, soil environmental conditions, and biogeochemical processes affect ecosystem dynamics in boreal forest ecosystems.The research of a dynamic organic soil biogeochemical model for simulating the effects of wildfire on soil environmental conditions and carbon dynamics of black spruce forests was accomplished recently by the researchers of Cold and Arid Regions Environmental and Engineering Research Institute. 

The researchers implemented a dynamic organic soil structure in the Terrestrial Ecosystem Model (DOS-TEM) to investigate the effects of fire on soil temperature, moisture, and ecosystem carbon dynamics. DOS-TEM consists of environmental, ecological, disturbance effects, and dynamic organic soil modules. Changes in organic layer thickness are computed from calculated changes in carbon pools following fire and during stand succession. DOS-TEM was parameterized based on studies reported in the literature and evaluated independently at sites in interior Alaska. This evaluation reveals that:(1)　 DOS-TEM is capable of accurately simulating the thickness and carbon content of organic soils.(2)　 without the dynamic linkage between soil organic thickness and carbon content, the model overestimates soil carbon in deep mineral soil horizons of dry black spruce ecosystems of interior Alaska. Sensitivity tests were performed to investigate issues related to spatial heterogeneity of carbon dynamics including soil drainage and fire frequency. Results show that both soil drainage and fire frequency are important in the carbon dynamics simulated by DOS-TEM, and should be considered in spatial applications of the model.

This study was supported through grants provided to S. Yi as part of the Major State Basic Research Development Program of China (973 Program)(2007CB411502) and One Hundred People Plan of the Chinese Academy of Sciences. Other support to A. D. McGuire and other coauthors for this study include grants through the North American Carbon Program (NASA NNG05GD25G), the Arctic System Science Program (NSF OPP-0531047 and OPP-0327664), the Bonanza Creek Long-term Ecological Program (funded jointly by NSF grant DEB-0423442 and USDA Forest Service).