‘Measurements include rainfall amounts, nitrate (NO3-N), ammonia (NH4-H), soluble reactive phosphate (SRP), and total nitrogen and phosphorus concentrations in bulk precipitation collected at multiple locations.
Soil chemical and physical characteristics are quantified on selected LTER watersheds adjacent to LTER vegetation sampling plots. Sampling was initiated in 1982, and is repeated every five years. A subset of variables (e.g., pH, Bray extractable P, total C, exchangeable cations) is measured on all sample dates, while additional specific variables (e.g., bulk density, soil texture, CaCO3 content, trace metals, extractable inorganic N) are measured less frequently. Methods for C and N analysis have changed over time.
The Konza burn history data is downloadable by year. Watershed names and codes listed are the current watershed designations (2010). Please note that several watershed designations have changed over the history of Konza. This is inevitable due to changes in research objectives but is problematic for those wanting to discover the full burn history of a given area. In some cases watersheds have simply been renamed to reflect changes in experimental burn treatments (e.g. R20A was formerly 1A). In other cases watersheds have been subdivided or aggregated from smaller watersheds (eg.
Standing dead and litter decomposition of big bluestem foliage and flowering stems were measured for two years using litterbag methods. Mass, nitrogen and phosphorus content were measured.
Data set contains estimates of end-of-season standing crop biomass (grams per square meter) of live graminoids, forbs, woody plants, and previous year's dead vegetation for 2 soil types (shallow and deep) on three core LTER watersheds representing three fire frequency treatments. Twenty quadrats (0.1 square meters) are harvested for each soil/treatment type. NOTE: Early (April) and mid-season (July) biomass was collected from 1983-1988, and these data are available by request.
In 1989, single transects spanning upland-lowland-upland topographic positions were established in a long-term unburned (0020B) and an annually burned (001D) watershed. Standing crop biomass data were collected in late season at 11 sites along each transect and sorted into live graminoids, forbs and woody plants, current year's dead, and previous years dead vegetation. Four 0.1 m2 quadrats were harvested at each of the 11 sites per watershed and all data except previous years' dead were combined to provide an estimate of aboveground NPP.
The concentration and isotopic composition of soil carbon and nitrogen were measured from select archived soil cores originally collected for the NSC01 dataset using an isotope ratio mass spectrometer coupled with an elemental analyzer. These soil cores were collected from the lowlands (25 cm depth) of four experimental watersheds in 1982, 1987, 2002, 2010, and 2015. The four experimental watersheds are 001d, n01b, 020b, and n20b.