Drone’s eye view of the lower saddle catchment at Nell’s gauge. Captured from a multispectral drone custom built to operate in the strong winds and high elevations of Niwot Ridge. Image shows spectra captured in the red and near infrared wavelengths. Lighter grey colors indicate healthy (green) vegetation, while yellow shades indicate bare ground and rock. Image credit: Oliver Wigmore
The Niwot Ridge Long Term Ecological Research (NWT LTER) program
is an NSF-funded, interdisciplinary research program with long-term goals of building a predictive understanding of ecological processes in high-elevation mountain ecosystems and contributing to broad conceptual advances in ecology. Built on a foundation of more than 35 years of research, NWT LTER research aims to better understand where and when environmental changes (i.e. temperature, terrain, wind, and precipitation) lead to ecological changes (i.e. snowpack, growing season length, water flow dynamics and nutrient limitation shifts) amongst an ecosystem characterized by spatial complexity and temporal variability and elucidating the mechanisms driving ecological responsiveness and stability.
The Saddle Catchment terrain and land surface maps above help investigators understand the spatiotemporal heterogeneity in alpine hydrology and ecologic functions. Layer 1 (from top) 10 cm digital elevation model and 1 m contours (1.4 times vertical exaggeration); Layer 2 visible image orthomosaic at 5 cm resolution showing distribution of land cover features, snow, trees, wetlands, etc.; Layer 3 normalized difference vegetation index (NDVI) at 5 cm resolution is a proxy for vegetation productivity, healthier vegetation areas are shown in darker green with yellow and representing low/no vegetation; Layer 4 (bottom) thermal infrared image at 25 cm showing land surface (skin) temperature from hot (red) to cold (blue). All data presented here were captured on June 21, 2017. Map credit: Oliver Wigmore.
With the latest renewal funding, the Niwot Ridge Saddle Catchment research site is the ideal location for studying new science questions. The site is located 5.6 km from the Continental Divide, along a ridge-top, but in a shallow saddle between the east and west knolls. To its south side lies the Tundra Lab. Its western half is a snow accumulation area and its eastern half remains snow-free most of the winter. The roughly 160 acres site contains several distinct vegetation communities. The site is naturally equiped to handle science exeriments that bridge hydrology, biogeochemistry and ecology.
NWT LTER lead Investigator, Katie Suding, and co-investigators Ben Livneh, Jason Neff, Noah Molotch and Eve Hinckley are forming a working group interested in coupling hydrologic connectivity with biogeochemical processing on the Saddle Catchment and then expanding this to bridge the hydrologic and biogeochemical modeling with the ecology.
Airborne photo of Niwot Ridge Saddle Catchment research site and the tundra lab. Photo credit: Oliver Wigmore and his drone.
For instance, access to airborne measurement is advancing the investigation of spatiotemporal heterogeneity in ecohydrologic processes within the high alpine. Earth Lab post-doctoral fellow Oliver Wigmore is mapping the Saddlel Catchment's terrain and land surface features with a custom built Unmanned Ariel System (UAS, but also known as a drone). The data will be used to investigate spatiotemporal heterogeneity in alpine hydrology and ecologic functions.
As the investigators continue refining their science questions, planning for experiments and parameterizing models, they keep the larger goal in mind: to better understand the mountain system’s flow of water and nutrient cycling in a more variable climate.