Carbon and water fluxes from the european terrestrial biosphere: reducing uncertainty through combining monitoring with process based modeling

• Autores: Trevor Keenan
• Directores de la Tesis: Carlos A. Gracia Alonso (dir. tes.), Santiago Sabaté Jorba (codir. tes.)
• Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2009
• Idioma: español
• Tribunal Calificador de la Tesis: Josep Piñol Pascual (presid.), Jaume Flexas Sans (secret.), Maurizio Mencuccini (voc.)
• Materias:
  • Ciencias de la tierra y del espacio
• Texto completo no disponible (Saber más ...)
• Resumen

  • This thesis focuses on carbon and water fluxes (including biogenic Volatile Organic Compounds (BVOC)) from forest canopies, and our ability to model them using detailed process-based models, both under current climatic conditions and future projections.

    The thesis is strongly focused on flux responses to water stress conditions commonly experienced in Mediterranean climate regions during the summer dry period, combining data analysis with model inter-comparisons in order to further our understanding of the processes which control forest canopy flux responses to drought. This includes a strong focus on stomatal conductance, mesophyll conductance and biological limitations to water stress. Physiological limitations to photosynthesis are concluded to be the dominating process in controling long term flux responses to soil water stress.

    Two chapters are dedicated to an analysis of different modeling approaches for estimating the BVOC emissions from European forest canopies. Three different emissions models are coupled to the GOTILW+ forest eco-physiological model, and the emissions estimates from each are assessed for both present and potential future conditions. The emissions models are shown to perform similarly under current climatic conditions, but diverge strongly under projected future climatic change. Further investigation examines the state of the art knowledge on seasonal changes in BVOC emissions, and how such changes are incorporated in different model currently used on the global scale.