Date Range:
Monday, January 9, 2012 to Sunday, December 31, 2023
Publication Date:
Friday, August 9, 2024
To estimate seed reproduction, flowering stem mass, height, and population densities of three dominant prairie grasses: Andropogon gerardii (ANGE), Sorgastrum nutans (SONU), and Schizachyrium scoparium (ANSC) in the Konza Prairie LTER watersheds.
Location of Sampling Stations: Florence and Tully locations of un-grazed watersheds: 001d, R01a, R01b, 002c, 002d, 004a, 004b, 020b, R20a, R20b, 0SpA, 0SpB, 0SuA, 0SuB, 00FA, 00FB, 00WA and 00WB. Sampling is done 2-3 m away from the permanently marked species composition transect (see PVC maps)
Frequency of Sampling: Once per year at the time of seed maturation (Oct to Nov).
Variable Measured: 1. Flowering stem heights (in centimeters); 2. Density of flowering stems (No. per m2); 3. Weight of flowering stems (g per m2)
Methods: Because these measurements involve destructive sampling, no permanently marked plots were set up. All samples are taken 2-3 m parallel to the permanently marked species composition plots at each LTER site.
Individual flowering stem heights: A quasi-random walk is initiated adjacent to the permanent LTER transects during which 25 sampling points per transect (100/LTER treatment) are located at intervals of about 2 m. At each sampling point, the stem height for the nearest (no more than 1m from observer) flowering individual of each of the three species is measured to the nearest cm. Mean flowering stem height is calculated for each species at each site from the 100 values.
Density and weight of flowering stems: Along a transect parallel to the permanent LTER plant species composition transects but on the opposite side from where the PAB biomass collections for the year have occurred, six 0.25 m2 plots (50cm x 50cm) per transect (x4 transects = 24 per site) are sampled. Each plot is 3 m from the species composition marker and 10 paces from the next plot. Within each of these plots, the number of flowering stems of each species is counted and the stems are clipped at ground level, bagged by species, oven dried at 60oC, and weighed. The density of flowering stems (No. per m2) and the mean biomass of flowering stem (g per m2) are calculated for each species.
For additional metadata information see: http://lter.konza.ksu.edu/sites/default/files/DC.pdf
For additional methods information see: http://lter.konza.ksu.edu/sites/default/files/MM.pdf
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