Crampton Lake NEON / CRAM

Crampton Lake (CRAM) is an aquatic NEON field site located in northern Wisconsin in Vilas County near the town of Land O' Lakes at the Wisconsin/Michigan border. The site is managed and hosted by The University of Notre Dame Environmental Research Center (UNDERC). Crampton Lake is a clearwater lake with a watershed of roughly 0.6 km² (148 acres). It has an average depth of 4.6 m (15 ft.) and maximum depth of 19 m (62 ft.). The surface area of Crampton Lake is 0.25 km² (61 acres). CRAM is surrounded by boggy mixed hardwood/conifer forests and is located in one of the most lake-abundant regions of the United States. CRAM is located within the Great Lakes Domain (D05), which includes northern Ohio, Michigan, northern Wisconsin, and parts of Indiana and Illinois. D05 also includes three terrestrial sites and one additional aquatic site. [1] [2] [13]

The climate of northern Wisconsin is characterized by bitterly cold winters and generally cool summers with brief times of excessive heat. Precipitation varies from year to year, with the majority of precipitation usually falling during the warmer part of the year. Snowfall also varies from year to year, however, the very northern portion of the state can see heavy snowfall due to lake effect events along the southern shore of Lake Superior. The area can also be subject to severe winter storms and thunderstorms. More specifically at Crampton Lake, the climate is classified as a humid microthermal marked by the absence of a dry season, extended summers and cool temperatures throughout most of the year. The mean annual temperature of CRAM is 4.3°C (39.74°F) and mean annual precipitation is 794 mm (31.25 in.). Due to extreme cold winter patterns, CRAM has an icy surface layer lasting usually from November to March. [1] [2] [9] [14] [15]

The geology of Crampton is closely correlated with glaciation largely from the Laurentide Ice Sheet dating back 18,000 years. The bedrock materials that make up the geological formations of this site are migmatite, amphibolite and quartzofeldspathic gneiss [8]. Additionally, Crampton Lake is part of the White Mountain Plutonic-Volcanic Succession. [1] [2] [11]

The soils surrounding Crampton Lake are loamy, sandy and well-drained with moderate permeability rates. The taxonomic soil class for most of the site is Alfic Oxyaquic Fragiorthods. The official soil series that classifies the soils surrounding CRAM is known as the Gogebic Soil Series, named after Gogebic County, Michigan, which is due north of the CRAM site. The soils are sandy outwashes resulting from intense historic glaciation of this entire region. Soils at Crampton Lake have diminished capacity for cation exchange, which leads to acidification and, in turn, to the development of peat bogs, a characteristic feature surrounding the site. [9] [10]

Crampton Lake is a seepage lake with no remarkable inlet and no visible outlets leading to permanent or perennial streams. The lake is largely fed by rain with much smaller contributions from snowmelt and groundwater below the site. Crampton Lake undergoes stratification in the warmer months (May-September) and the depth of thermal layer (metalimnion) ranges from 2-7 m (6.5 - 23 ft.). The bottom of the lake goes anoxic in the summer months. Like the majority of the lakes in the region, Crampton Lake is ice covered from late November until late March. Surface runoff is minimal with up to 50 mm (2 in.) per year and is snowmelt dominated with up to 4 mm (0.16 in.) per day in March and April. [2] [3] [12] [13]

The Crampton Lake site is a part of the Northern Mesic Forest Ecosystem. It is considered a woody wetland, containing bogs, and sits within mixed deciduous/coniferous forests. Dominant vegetation types that surround the shores of CRAM include sugar maple (Acer saccharum), red maple (Acer rubrum), American beech (Fagus grandifolia), eastern hemlock (Tsuga canadensis), paper birch (Betula papyrifera), aspen (populus tremuloides), and balsam fir (Abies balsamea). [4] [5]

The principal fish species found in Crampton Lake are bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), and yellow perch (Perca flavescens). These three species account for greater than 95% of the total fish biomass in the lake. Smaller populations of central mudminnow (Umbra limi), Johnny darter (Etheostoma nigrum), golden shiner (Notemigonus crysoleucas), and pumpkinseed (Lepomis gibbosus) make up the aquatic community as well. Some of the species that are observed and collected for NEON aquatics observation sampling (AOS) at CRAM are bluegill, largemouth bass, central mudminnow, yellow perch, golden shiner, and pumpkinseed. [2] [3]

Crampton Lake falls within one of most studied regions in America. Active research has taken place at the University of Notre Dame Environmental Research Center (UNDERC) for over 85 years. Martin Gillen, the man who owned the land at UNDERC before he gifted it to the university in 1936, allowed early limnologists to access the property to research all of the glacial lakes at the site. Ever since then, the site has been an important area for many interdisciplinary researchers including ichthyologists, biogeochemists, ecologists and limnologists. In particular in the 1950s, a limnologist and former president of the Association for the Sciences of Limnology and Oceanography (ASLO) began conducting whole-lake manipulation studies. This was a cutting-edge methodology at the time and continues to be a valuable research method for lake ecology and lake ecosystems. Shortly after this, Notre Dame staff began taking serious steps to make UNDERC a comprehensive research station with multiple facilities and equipment to foster long stays at the site. In recent years, NEON staff have forged collaborative relationships with terrestrial researchers at the UNDERC site and have shared data sets to reinforce key findings regarding sedimentation, eddy covariance, and tree ring data. [7]

Crampton Lake is hosted and managed by the University of Notre Dame Environmental Research Center (UNDERC). UNDERC is close to many acres of largely undisturbed wilderness on the border of Michigan and Wisconsin. A core mission of UNDERC has been to advance the fields of aquatic ecology and limnology. It has served as an important location for limnological and ecological research for over 65 years. Key topics of research conducted at UNDERC include dystrophic bogs, nitrogen exchange, glaciation, and flora/ fauna sampling. [6] [7]

Site characterization for CRAM began on May 4th, 2015. The sample readiness review (SSR) for Crampton Lake commenced in July 2015. Aquatic Observation System (AOS) began in September 2015. Two years later, the aquatic instrumentation system (AIS) was set up in November 2017.