The following document contains a short summary about some hydrogeological parameters that are important to know the behaviour of groundwater and the main processes involved in the nitrogen and the carbon cycle and its relation with underground stored water. The main thesis part is the explanation of a laboratory experiment done with riverbed sediments. The laboratory experiment tries to control some of the parameters that affect the riverbed soil in an artificial recharge basin in or der to observe how these parameters modify the soil behaviour referring to the microbial growth. Different compounds were added to jars that cointain the riverbed soil and different moisture conditions were performed; then soil and gas samples were taken d uring 50 days at different interval times. These samples were analysed to find how the nitrogen and the carbon was changing in the soil. From the experiment results it is possible to say that, with the conditions applied to the riverbed soil jars, the nitr ogen and carbon family compounds content was no despicable and different biochemical processes occurred in the riverbed soil. Carbon dioxide emissions (and concentrations) showed that the riverbed soil was active during the experiment and some nitrous oxid e and methane was emitted although it is not possible to say that different moisture conditions or different substrate added modifies the soil biochemical response with different compound production