Jason Mercer

United States Geological Survey | USGS

Isotopic exchange with atmospheric vapour can strongly influence the isotopic values of evaporating surface water bodies (e.g., lakes), influencing our understanding of hydrological processes across aquatic and terrestrial environments. Rather than measure the isotopic values of the atmosphere directly, it is much more common to estimate values by...

Microform is important in understanding wetland functions and processes. But, collecting imagery of and mapping the physical structure of peatlands is often expensive and requires specialized equipment. We assessed the utility of coupling computer vision-based structure from motion with multi-view stereo photogrammetry (SfM-MVS) and ground-based ph...

Abstract. Measurements of the isotopic composition of water recovered from soil at different tensions provide a powerful means to identify potential plant water sources and quantify heterogeneity in residence time and connectivity among soil water regions. Yet incomplete understanding of mechanisms affecting isotopic composition of different soil w...

Small mountain lakes function as temporary storage basins for rain and snowmelt-derived water. Many small lakes lose water seasonally, but questions remain about the processes involved and effects on watershed hydrology. Evaporation and groundwater outflow from lakes may influence baseflow in streams, hydrologic connections among lakes, and water f...

The utility of a particular tracer to perform hydrograph separations depends on the dominant watershed properties combined with meteorological patterns; therefore, drawing conclusions from one tracer can be misleading. Combining information from multiple tracers can reveal complimentary insights that advance our knowledge of runoff generating proce...

Measurements of the isotopic composition of separate and potentially interacting pools of soil water provide a powerful means to precisely resolve plant water sources and quantify water residence time and connectivity among soil water regions during recharge events. Here we present an approach for quantifying the time-dependent isotopic mixing of w...

Ecosystem function and stability are highly affected by internal and external stressors. Utilizing paleobotanical data gives insight into the evolutionary processes an ecosystem undergoes across long periods of time, allowing for a more complete understanding of how plant and insect herbivore communities are affected by ecosystem imbalance. To stud...

Hydrological conditions play an important role in provisioning the exceptionally valuable ecosystem services and functions of wetlands. In alpine areas, wetland functions and services are expected to be very sensitive to climate-mediated changes in hydrology. However, few field studies of alpine wetland hydrology currently exist, thus limiting unde...

Mountain peatlands are susceptible to a changing climate via changes in the water cycle. Understanding the impacts of such changes requires knowledge of the hydrological processes within these peatlands and in the upland forests that supply them with water. We investigated hydrological processes in peatland catchments in the Rocky Mountains by deve...