Determination of microbial decomposition rates of first-order in fluid-saturated or fluid-partially saturated porous media of the soil- and groundwater areas, comprises flowing a water sample to be examined through successive reactors

The method for the determination of microbial decomposition rates of first-order in fluid-saturated or fluid-partially saturated porous media of the soil- and groundwater areas, comprises flowing a water sample to be examined through successive reactors (1, 2, 3, 4, 5),which are switched in a row, are open or closed, are intermittently operated and are filled with fluid-saturated or fluid-partially saturated porous medium to be examined in natural or disturbed storage for exchanging each of the pore volumes after observing a down time from bottom to top. The method for the determination of microbial decomposition rates of first-order in fluid-saturated or fluid-partially saturated porous media of the soil- and groundwater areas, comprises flowing a water sample to be examined through successive reactors (1, 2, 3, 4, 5),which are switched in a row, are open or closed, are intermittently operated and are filled with fluid-saturated or fluid-partially saturated porous medium to be examined in natural or disturbed storage for exchanging each of the pore volumes after observing a down time from bottom to top, removing the pore water samples during or after exchanging the pore volumes, analyzing the pore water samples upon environment parameters and material concentrations, measuring the down time between the pore volumes exchange, so that the pore water samples have a significant concentration difference between two time sections upon the ingredients to be tested in the removed pore water samples. Before beginning the first down time, a conditioning of all reactors takes place so long by multiple pore volume exchange with the water sample to be examined until no concentration difference is detectable between an inlet and outlet of the reactors to determine the abiotic portion of the material reduction, where down time amounts to several days. The decomposition rates are determined on the basis of the concentration reduction of the material to be examined in dependent of the time related to a first experimental reactor, the concentration reduction of the material to be examined in dependent of the time related to a second experimental reactor, the concentration reduction of the material to be examined in dependent of the time from the first experimental reactor to the second experimental reactor and the material concentration in the porous medium after the end of the experiment, and are determined under the consideration of the environment parameters such as pH-