Spruce and Peatland ResponsesUnder Changing Environments
This data set contains empirical physiological, morphological, and chemical data collected on two dominant conifer species, Picea mariana and Larix laricina, between May 2016 and August 2017 at the SPRUCE (Spruce and Peatland Responses Under Changing Environments) experiment that assesses the response of peatland ecosystems to whole-ecosystem warming and elevated atmospheric CO2 concentrations. The SPRUCE experiment is located 40 km north of Grand Rapids, MN, in the USDA Forest Service Marcell Experimental Forest.
This data set reports community-level CO2 and CH4 flux measurements for the SPRUCE experimental study plots located in the S1-Bog. Surface flux measurements of CO2 and CH4 were made using open-path analyzers over an area of 1.13 m2 within each of 16 plots. A custom-designed chamber encloses the hummock-hollow topography and allows point in time measurements of the shrub, forb, Sphagnum spp. and the complex microbial community. These observations were made with ambient light and imposed dark conditions to allow estimates of community daytime and night respiratory processes. This data set is all inclusive – beginning in 2011 and continuing through August 2019 of the Whole-Ecosystem-Warming (WEW) phase of the experiment.
This data set reports plot-specific bog surface elevation measurements collected with the SPRUCE Elevation Transect (SET) instrument. Measurements are reported as absolute elevation in meters above mean sea level for two locations in each of the SPRUCE experimental treatment plots and additional ambient boardwalk plots -- 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 20 and 21.
This data set reports measurements collected from June 2013 through August 2018, but it will be appended annually as new data are collected.
This data set reports shrub layer growth assessments for the S1-Bog on the Marcell Experimental Forest in Minnesota from 2010 through 2018. Data were obtained by destructively harvesting two 0.25 m2 plots within defined plot areas of the S1-Bog or SPRUCE experimental plots. In 2015, SPRUCE plots 4, 6, 8, 10, 11, 13, 16, 17, 19 and 20 were enclosed in the SPRUCE enclosures. Prior to 2015 all data are for open ambient conditions. In early years a distinct hummock and a hollow sampling square were both collected, but in later years unsampled hollow areas became unavailable due to prior sampling or instrument installations.
All vegetation material above the Sphagnum surface of the bog was clipped and transferred to plastic storage bags which were then frozen until the samples could be sorted. Sorting was done by species, tissue type (leaves vs. stems) and tissue age (current-year vs. older tissues).
