Data from: Within-reach temperature heterogeneity is limited in a southern Appalachian stream network, southeastern USA
Data files
Jul 28, 2025 version files 4.76 MB
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dframe_temps15min.csv
4.71 MB
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README.md
2.43 KB
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site_env_v01.csv
44.70 KB
Abstract
Stream temperature monitoring networks, combined with geospatial data and statistical modeling, facilitate temperature mapping at the spatial resolution of inter-confluence stream reaches and at continental spatial extents. Comparatively few monitoring efforts quantify spatiotemporal temperature heterogeneity within inter-confluence stream reaches. We measured within-reach temperature heterogeneity for six study reaches in a southern Appalachian stream network, southeastern USA. Within each reach, we logged temperature at 27 monitoring points every 15 minutes for three days during early summer and three days during late summer of 2018. Analysis of variance indicated that daily minimum, mean, and maximum water temperature metrics vary more among reaches than within reaches. For example, the difference in daily mean temperature from the warmest to coldest reach was 8.7°C, whereas within-reach variation never exceeded 2.3°C for any of the three daily temperature metrics. Mixed effects models indicated that most variation in the three daily water temperature metrics can be explained by reach-resolution covariates, including elevation, watershed area, and forest cover. The limited within-reach temperature heterogeneity was driven by longitudinal position along the reach but, surprisingly, not by riparian canopy gaps, vertical stratification, or other factors. Our findings verify that temperature mapping at the resolution of inter-confluence reaches effectively captures temperature gradients and indicate that thermally-sensitive organisms have limited access to fine-scale refuge in southern Appalachian streams. Generally, within-reach temperature heterogeneity should be quantified in more geographic and physiographic contexts to understand natural and anthropogenic drivers of this variation, validate reach-resolution temperature mapping, and forecast climate change refuges.
Dataset DOI: 10.5061/dryad.931zcrjx9
Description of the data and file structure
These files include (1) stream temperature monitoring data from the Little River watershed (Blount County, Tennessee) and (2) associated geographic and environmental variables describing the monitoring locations.
Files and variables
File:
site_env_v01.csv
Description:
Variables
- COMID: Unique flowline ID from National Hydrography Dataset (NHD).
- lon: Longitude in decimal degrees.
- lat: Latitude in decimal degrees.
- reach: One of six reach name abbreviations.
- transect: One of nine transect numbers.
- point: One of three point numbers, or alternative air temperature monitoring point.
- period: Early or late summer monitoring period denoted 1 or 2, respectively.
- attach: Method of logger attachment in stream.
- bank: Abbreviation for point on left or right bank.
- azimuth_300m: Azimuth in units of degrees of transect.
- lon_pos: Longitudinal distance of transect in meters from the upstream-most transect.
- lat_pos_m: Lateral distance of point in meters from the streambank.
- lat_pos: Lateral position of point defined as stream middle or edge.
- vert_pos: Vertical position of point defined as surface or benthic.
- vert_pos_cm: Vertical position of point in centimeters from water surface.
- vert_strat: Type of monitoring point defined as surface, benthic, or neither.
- S_depth: Water depth in centimeters on monitoring day 1.
- E_depth: Water depth in centimeters on monitoring day 3.
- canopy: Riparian canopy cover measured as percent covered.
- Missing data: mentioned as NA
File:
dframe_temps15min.csv
Description:
Variables
- reach: One of six reach name abbreviations.
- transect: One of nine transect numbers.
- point: One of three point numbers, or alternative air temperature monitoring point.
- period: Early or late summer monitoring period denoted 1 or 2, respectively.
- day: Monitoring day 1, 2, or 3.
- date_time: Date and time of temperature measurement.
- WT: Water temperature measured in degrees Celsius.
- AT: Air temperature measured in degrees Celsius.
Access information
Other publicly accessible locations of the data:
- n/a
Data was derived from the following sources:
- n/a