[Tracking Riverine Nitrate Sources and Transformations in the Yiluo River Basin by Nitrogen and Oxygen Isotopes].

The impacts of natural processes and anthropogenic input on riverine nitrate (NO) could be identified by NO concentrations and nitrogen and oxygen isotope ratios (N-NO and O-NO); however, the effects of variable land use on riverine NO sources and transformations remain unclear. In particular, the human impacts on riverine NO in mountain areas are still unknown. The Yihe River and Luohe River were used to elucidate this question due to their spatially heterogeneous land use.