Looking for hotspots of nitrogen cycling in an alpine-subalpine watershed

The drastic human modification of Earth's nitrogen cycle has been linked to many environmental problems including air pollution, water pollution, algal blooms, acid rain, and the fertilization of the entire globe, which leads to changes in local species composition, alien plant invasion, biodiversity loss, eutrophication, and other potential problems. Within a particular landscape on Earth's surface, certain areas or components of it are likely to be affected a lot more severely than others; that is, certain areas are hotspots of biogeochemical activity. This project was designed to locate nitrogen cycling hotspots within a heterogeneous alpine-subalpine watershed at the Niwot Ridge LTER site in the Front Range of the Rocky Mountains, Colorado, USA. I used spatially explicit sampling methods to characterize soil moisture, soil temperature, pH, and the nitrogen and carbon concentrations and stable isotope ratios in light and heavy soil fractions. I also measured ion concentrations in ephemeral streams that drain snowmelt from the watershed. While this early phase of the study does not include measurements of the reaction rates of important nitrogen reaction pathways, the measurements of the physical characteristics and chemical environment across the landscape suggest that vegetation is a dominating driver in determining landscape heterogeneity in nitrogen reaction rates. Furthermore, the measurements of ions in ephemeral streams suggest that nitrogen can be processed in this watershed by relatively small (50 m in length) patches of vegetation.