The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. Point transects were done throughout the sampling season to determine different substrate and cover types on the stream bottom.
Data Set Results
A/Ci curve parameters and modeled carboxylation, electron transport, and triose-phosphate utilization efficiency rates from shoots clipped from low, mid, and the top of tall, shrub canopies dominated either by Salix pulchra or Betula nana species. Six shoots were harvested from each 1m x 1m plot, two from each level in the canopy. These plots were located near the LTER shrub plots at the Toolik Field Staion, AK for point frame measurements, and all measurements took place the summer of 2012.
Within-canopy PAR was measured with a Delta-T SunScan wand every 15 cm from the ground to above the canopy under both direct and diffuse light. The data includes all outputs from the SunScan wand: time of measurement, spread of PAR sensors, total irradiance, total diffuse light, and individual outputs of 64-PAR sensors on the SunScan wand. These measurements were taken for 1m x 1m chamber flux (n=14) and point frame (n=19) plots as well as sites four montitored remotely by PAR sensors located above, within, and below shrub canopies.