SISS model data and script

This resource is linked to the following manuscript:
Lutz et al.: How Important is Denitrification in Riparian Zones? Combining Endmember Mixing and Isotope Modeling to Quantify Nitrogen Removal Processes, in review for Water Resources Research

This resource provides concentration and isotope data in a groundwater well field along a 2 km stream section in central Germany. We developed a mathematical model combining endmember mixing and isotope modeling to account for mixing of river water and groundwater, and quantify nitrate transformation at the study site (i.e., the SISS model). This enabled us to explicitly determine the extent of denitrification (as permanent nitrate removal process) and nitrate removal by additional processes associated with negligible isotope fractionation (e.g., plant uptake, microbial assimilation and dissimilatory nitrate reduction to ammonium) in the riparian system.

Content:
*the SISS model code
*chloride and nitrate concentration data from the field site
*nitrate and stable water isotope data from the field site