Comparison of carbon assimilation estimates over tropical forest types in India based on different satellite and climate data products

Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical forest types in India for a period of two years (September, 2006–August, 2008). The results indicate that the evergreen forest assimilate carbon at a higher rate while the rate is lower for montane grasslands. The comparison between the model results shows that there are large differences between these estimates, and that the spatial resolution of the input datasets plays a larger role than the algorithms of the models. The comparison exercise will be helpful for the refinement and development of the existing and future GPP models by incorporating the empirical environmental conditions

Comparison of carbon assimilation estimates over tropical forest types in India based on different satellite and climate data products

Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical forest types in India for a period of two years (September, 2006-August, 2008). The results indicate that the evergreen forest assimilate carbon at a higher rate while the rate is lower for montane grasslands. The comparison between the model results shows that there are large differences between these estimates, and that the spatial resolution of the input datasets plays a larger role than the algorithms of the models. The comparison exercise will be helpful for the refinement and development of the existing and future GPP models by incorporating the empirical environmental conditions. (C) 2011 Elsevier B.V. All rights reserved

Olive tree system in Mediterranean basin: a mid-term survey on C sequestration dynamics and modelling

The contribution that olive orchards can provide in climate mitigation should be more deeply analyzed given that these systems can stock large amount of C in woody compartments and soils. These systems could play a fundamental role especially over Mediterranean basin that is one of the most sensitive areas to climate change and where they are widely cultivated. However some issues are still open: what do we really know about the C-sequestration capacity provided by these systems? Can these really contribute to climate change mitigation both for current and future periods? In order to solve these questions, a mid-term study (3 years) was carried out at Follonica (Tuscany, central Italy), where an eddy covariance tower was installed over a typical rainfed olive orchard. Data from eddy covariance were then used for calibrating and validating two different models able at simulating C-exchange and biomass production from this system. Our work firstly allowed to assess the C-fluxes dynamics from this system and their relation with the main meteorological parameters and agricultural practices, thus indicating the magnitude of C-sequestration capacity offered by a typical Mediterranean olive orchard; as second the implementation of new tools that can be used for assessing the efficiency of mitigation strategies or to predict changes in mitigation capacity that these systems will probably encounter over the next decades.</br