Guadalquivir River

WP8 will perform an isotopic study of atmospheric gases (CO2, CH4 and N2O) and gases dissolved in water (O2, N2 and Ar). Estimates of primary production by GPP18O (photosynthesis/respiration balances) at different points from its source to its mouth. Isotopic study of tree rings (water use efficiency and effects of Global Change). Isotopic study of nitrates, nitrites and ammonium: denitrification processes and relationship with episodes of anoxia. Isotopic study of water and dissolved compounds: nitrates, nitrites, ammonium, DIC, DOC, sulphates, etc.