Prairie Pothole NEON / PRPO

Prairie Pothole (PRPO) is an aquatic NEON field site located about 160 km (100 mi.) northeast of Bismarck, North Dakota. This site's watershed is 1.4 km² (346 acres) and is managed by the U.S Geological Survey and U.S. Fish and Wildlife Service as part of the larger Chase Lake National Wildlife Refuge. PRPO sits among the restored prairie and is part of a matrix of small lakes, ponds, and ephemeral prairie potholes in the area. The region is characterized by an immense number of prairie potholes, which are depressional wetlands that are primarily freshwater marshes. The site is part of NEON's Northern Plains Domain (D09). The Domain has one other aquatic field site and three terrestrial field sites. PRPO is colocated with The Northern Plains- Woodworth (WOOD) terrestrial site. [1] [2]

North Dakota has continental climate characterized by vast variations in both seasonal and daily temperatures. Air flow throughout the region creates windy conditions. In the winter, arctic air masses create cold and dry conditions. Summer airflow from the Northern Pacific air masses bring warmer dry conditions, while occasional tropical air flow creates warm and wet conditions. This highly variably shift in air masses ultimately provides North Dakota with moderate precipitation annually of around 330-508 mm (13-20 in.). Average annual temperature ranges from 2.8-6.1°C (37-43°F), with winters often below -17.8°C (0°F) and summers above 32°C (90°F). The mean annual temperature in the vicinity is 4.9°C (40.8°F) and mean annual precipitation is 495 mm (19.5 in.). Precipitation varies from year to year, with more precipitation falling during the summer months when thunderstorm activity is the highest. Weather exhibits extreme variability, with periodic droughts, hailstorms, fluctuations in temperature, and frequent strong winds. The most severe storms can produce hail, tornadoes, or damaging straight-line winds. [5] [9] [11]

The geology of this site is characterized by glacial settlements of mud, clay, and silt underlain by the Pierre Formation. [7] [8]

Soils at this site are dominantly Mollisols in the subgroup Typic Haplustolls, with lesser proportions classified within the Inceptisols Order. The soils have textures of Fine-Loamy with lesser proportions of fine, fine-loamy over sandy, sandy-skeletal, and sandy textures. [7] [8]

The landscape around PRPO is characterized by an undulating matrix of small lakes, ponds, and ephemeral prairie potholes. The lake at PRPO is a year-long depressional freshwater wetland that fills with snowmelt and rain during spring and summer storms. [1] [2] [3]

PRPO lake is dominated by prairie grasses and sparse patches of reeds, cattails, and large woody debris in the riparian area. The landscape surrounding PRPO is dominantly characterized by rolling hills with herbaceous grasslands and legumes as the dominant vegetation type. [3]

Animals that call this area home include the Bison (Bison bison), Mule deer (Odocoileus hemionus), and Pronghorn antelope (Antilocapra Americana). Prairie potholes are unique habitat that provide various resources for birds such as the White Pelican (‎Pelecanus erythrorhynchos) and the piping plover (Charadrius melodus), an endangered species that relies on the Great Plains for breeding habitat. NEON conducts electrofishing, macroinvertebrate, and zooplankton sampling protocols at the PRPO site. [1] [2] [4]

Native American presence in the area dates back to 10,000 years ago, following the retreat of the continental glaciers. Before European settlers arrived, the Dakota or Lakota nation, as well as the Assiniboine, Cheyenne, Mandan, Hidatsa, and Arikara groups were present in what is now North Dakota. Native Americans and Euro-Americans came into contact in the 18th Century and further American settlement commenced in 1861 following the establishment of North Dakota as a territory. Since 1969, this site has been used for studying the response of wildlife to applied treatments of grazing, burning, idling, and annual cropping. The U.S. Fish and Wildlife Service conducts annual wildlife surveys to determine the size and health of nesting bird populations around the lake. The site has been historically tilled, cultivated, and grazed. [1] [6] [12] [13]

The U.S. Geological Survey and U.S. Fish and Wildlife Service manage the Larger Chase Lake National Wildlife Refuge-Woodworth where Prairie Pothole (PRPO) is located. At Chase Lake NWR, all but 1 km² (230 acres) of the 19.5 km² (4,835 acres) are designated as Wilderness Area. Land management at Chase LAKE NWR is focused on maintaining the biological diversity, integrity, and overall environmental health of the ecosystem in and around the lake. Private landowners play a role in protecting the wetlands and grasslands in the Prairie Pothole Region, which serve as critical migration and breeding habitat for birds. The primary human activities here are research and wilderness recreation, including bird watching. Limited trapping is allowed in the NWR with proper permits. Historically, grazing bison and wildfires caused by lightning helped evolve and shape the mixed-grass prairie. Current land management at PRPO is focused on continuing this cycle by re-seeding with native plant species and using light cattle grazing and prescribed burns to promote the growth of native species. [1] [10] [12]

Prairie Pothole is colocated with the site of Woodworth (WOOD). The initial site characterization was completed in 2014 with aquatics sampling beginning that same year. Aquatic instrumentation construction was completed in 2017 when data came online.