International Journal of Multidisciplinary Research and Development

Authors
Mohamed AA Mohamed, Insaf S Babiker, Tetsuya Hiyama

Abstract
North latitudes temperate and boreal forests play an important role in the global carbon cycle. However, their responses to climate variability are not fully understood. Meteorological data including incident photosynthetic active radiation (PAR), absorbed photosynthetic active radiation (APAR), air temperature, precipitation, and relative humidity were obtained for three coniferous forests from the Euroflux network with 1-4 years data collected between 1997 and 2000. Net primary production was modeled using APAR and biome-specific conversion efficiency in order to investigate the variations and magnitude of vegetation responses to environmental variables. Seasonal variations of NPP reflected the typical phenology of temperate forests with peak productivity in spring-summer due to limiting growing season and changes in incoming radiations. Monthly NPP was tightly correlated to temperature, relative humidity and PAR while no relation was found with total precipitation. Temperature controls the productivity of coniferous forests by directly enhancing their metabolic activity and indirectly accelerating decomposition of organic matter in soil.