Summaries of temperature and water table depth prior to peat sampling in Stordalen Mire, 2011-2017

This dataset provides summaries of temperature (T) and water table depth (WTD) conditions prior to the collection of peat samples from Stordalen Mire, Sweden, in July of 2011-2017. These summaries include the following files:

t_wtd_summaries_July2011-2017samplings.csv

This file gives summary statistics over various time intervals for the following environmental measurements:

AirTemperature: Mean daily air temperature (°C), obtained from automatic sensors at the nearby Abisko Scientific Research Station (ANS) (station ID 188790; the source file [ANS_Daily_Wx_Jul84_Dec17.txt] is not included due to sharing restrictions).

WTD: Water table depths (cm), obtained from Manual active layer and and water table depth measurements from the autochamber sites at Stordalen Mire, northern Sweden (2003-2017) (from Patrick Crill et al.).

The time intervals for these summaries are defined relative to the peat sampling date at each site (see EMERGE Sample Metadata Sheet for Samples with Microbiomes), which varies by site and year. The specific intervals are defined as follows:

7d: 7 days prior to the sampling date, plus the sampling date itself.

14d: 14 days prior to the sampling date, plus the sampling date itself.

21d: 21 days prior to the sampling date, plus the sampling date itself.

28d: 28 days prior to the sampling date, plus the sampling date itself.

growing: Time from beginning of growing season (defined as June 1) until (and including) the sampling date.

all_growing: Entire growing season (June 1 – Sept. 30).

For clarity, the start and end dates for each time interval (inclusive) are also given under the columns Start_Date and End_Date, where End_Date=Sampling_Date for all intervals except all_growing.

Summary statistics for each interval include: measurement count (n), median (median), mean (mean), and standard deviation (sd), and are given under the column names beginning with these statistic labels.

IMPORTANT NOTE:  For temperature, these statistics are calculated based on the average temperature measured on each day, meaning that the standard deviations do NOT account for within-day temperature variation. To provide short-term (1 day) temperature variation context for each sampling date, the within-day mean, minimum, and maximum air temperatures for the sampling date only (taken directly from the corresponding row & columns in the source ANS data file) are provided in the columns samplingdate_mean_AirTemperature, samplingdate_min_AirTemperature, and samplingdate_max_AirTemperature.

wtd_summaries_July2011-2017samples.csv

This file gives the percentage of time that each peat sample's depth midpoint (DepthAvg__) was at or below the water table depth (WTD), over each of the longer time intervals (≥21 days) defined above for the temperature & WTD summaries. (Intervals <21 days are not included due to the lower frequency of WTD measurements, which results in low n for shorter intervals.)

The first few columns are taken directly from the EMERGE Sample Metadata Sheet for Samples with Microbiomes, for the samples collected in July of 2011-2017 from the MainAutochamber sites. The last set of columns include the following, with the time interval labels (defined as in the above temperature summaries) appended at the end of each column name:

n_WTD_*: Number of WTD measurements used in the calculation.

pct_time_below_WTD_*: Fraction (relative to 1) of measured WTDs over the given time interval that were at or above the DepthAvg__ for each sample, which equates to the fraction of measurement timepoints during which the given sample was at or below the WTD. This is the same method used for calculating "% Time below water table" in Figure 6 of Singleton et al. (2018). For palsa sites, this value is automatically set to 0 based on the lack of a water table at all timepoints in the analysis.)

As above, the WTD values used for these calculations were obtained from Manual active layer and and water table depth measurements from the autochamber sites at Stordalen Mire, northern Sweden (2003-2017) (Patrick Crill et al.).

Funding acknowledgments

This research is a contribution of the EMERGE Biology Integration Institute, funded by the National Science Foundation, Biology Integration Institutes Program, Award # 2022070.

This research was also funded by the Genomic Science Program of the United States Department of Energy Office of Biological and Environmental Research, grant #s DE-SC0004632, DE-SC0010580, and DE-SC0016440.

The temperature summary has been made possible by data provided by Abisko Scientific Research Station and the Swedish Infrastructure for Ecosystem Science (SITES).

We thank the Swedish Polar Research Secretariat and SITES for the support of the work done at the Abisko Scientific Research Station. SITES is supported by the Swedish Research Council's grant 4.3-2021-00164.