Niwot Ridge NEON / NIWO

The Niwot Ridge Mountain Research Station (NIWO) is a terrestrial site within the Front Range of the Rocky Mountains, 27 km (16.8 mi.) west of Boulder, Colorado and 6 km (3.7 mi.) east of the Continental Divide. NEON collects data over 13.4 km² (3311 acres) at the site, which is on land managed by the University of Colorado in Boulder and the U.S. Forest Service. Sitting at 3000-3600 m (9843-11810 ft.) in elevation, this site's climate and biota are representative of the diverse landscapes of the Southern Rocky Mountains. Diverse gradients allow NEON to challenge questions surrounding land use change, climate impacts, and disturbance processes at multiple elevations. NIWO is part of NEON's Southern Rockies and Colorado Plateau Domain (D13). D13 includes one other terrestrial site and two aquatic sites. NIWO is located near the COMO aquatic site. [1]

NIWO is located in the Southern Rockies, which, due to elevational changes, have a climate characterized by dramatic differences in precipitation and temperature over very short distances. In general, precipitation decreases and temperature increases with a decrease in elevation. NIWO ranges through several elevation gradients, creating diverse climates across the region. It is considered an alpine tundra ecosystem. Mean annual temperature is 0.3°C (32.5°F) with the majority the of the mean annual 1005 mm (39.5 in.) of precipitation being snow at the highest elevations. Snow is brought from the east by cyclonic easterly upslope flows of air at the lower elevations. Spring storms often occur during the afternoons. Fall is the driest season in this region with the lowest average precipitation recorded. At the lower elevations there are many distinct microclimates within the saddles, knolls, moraines, and other glacial features. [2] [4] [7]

The geology at Niwot Ridge consists of schist, migmatite, and biotitic gneiss. [5]

The dominate soil order found at NIWO are Mollisols. Overall, soil can be described as Coarse-loamy - mixed - superactive Typic Haplocryolls. [1]

NIWO is located within the Rocky Mountains, which are covered in snowmelt-fed springs and upland catchments which deliver water to downstream basins. Boulder receives most of its drinking water from these basins. [6]

Flora varies along an elevation gradient at NIWO. On the low-elevation east and south facing slopes, lodgepole pine (Pinus contorta) and aspen (Populus tremuloides) groves dominate the landscape. The transition zone between the closed subalpine forest and alpine tundra are full of meadows interspersed with stunted patches of coniferous trees. The alpine tundra sits above the treeline and is dominated by herbaceous plants such as Ross’ avens (Geum rossii) and curly sedge (Carex rupestris). The steepest, highest regions of NIWO are dominated by microplants and scree.

The Rockies have many diverse animal species that call them home including Black bear (Ursus americanus), snowshoe hare (Lepus americanus), porcupine (Erithizon dorsatum) and elk (Cervus danadensis). Niwot ridge has both seasonal and year round residents such as the white-tailed ptarmigan (Lagopus leucura) and is host to 31 species of mammals. NEON collects fauna data on small mammals, birds, ticks, mosquitoes, and ground beetles. Commonly sampled species at NIWO are deer mice (Peromyscus maniculatus), redbacked voles (Myodes gapperi), and the ground beetle Pterostichus surgens. [1] [2]

The area has experienced multiple ecological disturbances throughout history, including stand-replacing fires, episodic insect outbreaks, and occasional wind damage. In the early 1900s the logging industry clear cut the forest. The area is encompassed within Niwot Ridge, which was established as a site in the NSF-sponsored Long Term Ecological Research (LTER) Program in 1980. [8]

NIWO is hosted by and operated under the Forest Service and the University of Colorado-Boulder (CU Boulder). The Mountain Research Station (MRS) at Niwot Ridge is an interdisciplinary research facility of the Institute of Arctic and Alpine Research at CU Boulder, which facilitates research to understand mountain ecosystems and advance education. Within this station, research is conducted via several organizations sponsored by the National Science Foundation including the Niwot Ridge LTER, Boulder Creek Critical Zone Program, and the NEON program. The MRS program was established at its current site in 1920 on property leased by the U.S. Forest Service. Research themes at Niwot Ridge include the movement of energy and nutrients across the subalpine-alpine landscape, the influence of nitrogen deposition on ecosystems and hydrology, and the influence of climate on diversity and ecosystem function. [1] [3] [9]

Characterization of NIWO began in May 2015. Terrestrial sampling readiness reviews were completed and initial site sampling began in August of that year. Tower establishment was completed and TIS became operational in April 2017.