With BIOME-BGC Model On The Carbon And Water Fluxes Of The Typical Ecosystem

Carbon is one of the most important life chemical elements. Its exchange between the atmosphere and the living creature is one of the most important ecological processes, that is the productivity formation process. The carbon circulation is the important part of the global biogeochemistry circulation, and is the physical foundation that maintains mankind existence. The yearly rainfall and evaporation quantitively reflects the abundance of water resources in a region to a certain degree. Along with the development of the society and the economy in the western part of Northeast China, the conflicts between water resources supply and demand is increasingly obvious in the semiarid area.In this study, BIOME-BGC model was used to simulate CO₂ and latent heat fluxes of grassland and cropland ecosystem at Tongyu of Jilin Province, and the simulations were compared with the observations from the long-term station on aridification and the ordered human activity. This observation station is also one of the reference sites of Coordinate Enhanced Observation Period (CEOP).The CO₂ fluxes of grassland ecosystem simulated by BIOME-BGC model are not very ideal. In regard to the grassland ecosystem, the plant roots and the soil microorganism respiration velocity and its seasonal variation are mainly under a conditional control of the soil temperature and humidity. The biggest leaf area index in simulations is 2.9 and may be a little smaller than the normal from experiences, causing the gross primary productivity of the whole year a little smaller. After deducting the autotrophic respiration, the net primary productivity is 278.9 gC m^-2·a^-1, and the net ecosystem productivity is 43.9 gC m^-2·a^-1 after deducting the heterotrophic respiration.Compared with the grassland, the NPP of the cropland ecosystem is smaller. The rainfall (rainfall here does not include snow because snow is not recorded there) difference...