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This repository contains field data and floodplain boundary shapefiles for 14 floodplain sites in the United States used in Iskin and Wohl (2023). The data are the original field data associated with the 14 field sites, including GPS locations of floodplain transects, floodplain patches, sediment cores, and large wood, and shapefiles of the delineated floodplains.

Description of the data and file structure

This dataset was collected to investigate floodplain heterogeneity in the United States and contains data from 14 natural floodplains, collected between 2010 and 2022. The data were collected along transects approximately evenly spaced and perpendicular to the valley trend with handheld Garmin GPS units (all locations), hand tapes (wood diameters), and hand-driven sediment corers (soil cores), except where noted explicitly in the data files. Dates of data collection and descriptions of classes identified visually in the field are included in each data file. The data documents areas of the floodplains that were accessible by car and foot at the time the data were collected and that time and resources allowed.

There is one folder for each field site. The folder contains on workbook with the following four sheets and one shapefile:

Class Descriptions contains field site name, date the data were collected, and written descriptions of the floodplain class types and the associated class numbers throughout the rest of the file. There is an unlimited number of classes per site. If the Class Boundaries sheet is blank, no class data was collected at the site or came from another study cited in Iskin and Wohl (2023).

Class Boundaries contains boundaries of each patch of each class for each floodplain transect. There are up to 10 transects per site, unlimited number patches per class and per transect. Start Lat, Start Long, End Lat, and End Long indicate the linear/on-transect boundaries of the patch in Decimal Degrees and WGS 1984 coordinate reference system. Other Lat and Other Long indicate boundaries for other interesting features in the patch and on the transect with details given in the Notes column. Optional Notes provides field and/or data processing comments. - indicates missing data. If the Class Boundaries sheet is blank, no class data was collected at the site or came from another study cited in Iskin and Wohl (2023).

Large Wood contains on-transect locations (Lat and Long) and diameter (in centimeters) of all the pieces of large wood ( 1m long and 10cm diameter) on the transect and/or logjams (at least three pieces of large wood), including which transect it was located on and which class it was in. A few sites have length (cm) of wood pieces. Optional Notes provides field and/or data processing comments. - indicates missing data. If the Large Wood sheet is blank, no large wood was encountered at the site or came from another study cited in Iskin and Wohl (2023).

Sediment Cores contains locations (Lat and Long) of sediment cores taken for each class. Date Collected lists the specific date each core was collected, Transect indicates approximately which transect the core was taken on, Class indicates which class the core was taken in, and Core indicates which number core the data refers to (generally, sites have two cores per class). Depth indicates the range of depth below the surface of the soil the core is from, Water Content indicates categorical wetness of the core (dry no moisture at all; moist evidence of moisture, i.e. clumping, dampness; saturated fully wet core); %Sand, %Silt, and %Clay indicate the content of each core in percentage; and Soil Texture indicated the categorical soil texture. Optional Notes provides field and/or data processing comments. - indicates missing data. %Sand, %Silt, %Clay, and Soil Texture data from analysis performed by Ward Laboratories Inc. in Kerney, Nebraska. If the Large Wood sheet is blank, no large wood was encountered at the site. If the Sediment Cores sheet is blank, no sediment cores were collected at the site or came from another study cited in Iskin and Wohl (2023).

Shapefile shapefile of the floodplain boundary used in the analysis in Iskin and Wohl (2023). The shapefiles were hand drawn in ArcGIS Pro using the field data, and other raster data collected from various sources (digital elevation models, Sentinel-2A mosaics, and National Park boundaries). The floodplain boundaries should be considered approximate and are based on data available as of 2022. They were generally drawn to exclude most of the human-impacted areas, but not all were excluded. Ten-meter geodesic buffers were added to most of the floodplain boundaries to account for field and/or user error. Buffer details provided with each file name below.

Acronyms

AGA Altamaha River, Georgia
CSC Congaree River, South Carolina
DFWY Downs Fork, Wyoming
DWY Dinwoody Creek, Wyoming
EIL Embarras River, Illinois
EPC East Plum Creek, Colorado
HWA Hoh River, Washington
LOR Lookout Creek
NSV North St. Vrain Creek, Colorado
RTCO Rough and Tumbling Creek, Colorado
SDWA Sol Duc River, Washington
SMT Swan River, Montana
SOK Sand Creek, Oklahoma
WBJ West Bijou Creek, Colorado

P# - indicates a specific patch of the numbered class
T# - indicates transect number

CPOM Coarse particulate organic matter
DBH diameter at breast height, indicates the approximate diameter of standing trees in the class/patch
FP floodplain
HWM high water marks, indications of recent flow and minimum approximation of flow depth

Data Files

AGA: Field Data_AGA.xlsx Contains one additional sheet titled Wet Patch Boundary that includes GPS points (Lat, Long, and Point ID) outlining the perimeter of a single patch.

FP_AGA_10m.shp Buffered (10m) floodplain polygon

CSC: Field Data_CSC.xlsx Only contains calculated large wood load data used in Iskin and Wohl (2023). No class/patch or sediment core data was collected at this site.

FP_CSC_10m.shp Buffered (10m) floodplain polygon

DFWY: Field Data_DFWY.xlsx Only contains transect locations and calculated large wood load data used in Iskin and Wohl (2023). No class/patch or sediment core data was collected at this site.

FP_DFWY_nobuffer.shp Floodplain polygon (no buffer, adjacent to DWY)

DWY: Field Data_DWY.xlsx Only contains transect locations and calculated large wood load data used in Iskin and Wohl (2023). No class/patch or sediment core data was collected at this site.

FP_DWY_nobuffer.shp Floodplain polygon (no buffer, adjacent to DFWY)

EIL: Field Data_EIL.xlsx some logjams measured by piece with diameter and length of large wood, some by piece with large and small wood (SW; < 1m long and/or < 10cm diameter), and some with the box method. The box method calculates volume of the logjam from approximate length (L) x width (W) x depth (D) of the logjam multiplied by (1 Porosity (P%)), instead of measuring all of the pieces of large wood individually. Porosity is measured visually and represents the percentage of the rectangular prism, or box, that is made up of air space.

FP_EIL_10m.shp Buffered (10m) floodplain polygon (buffer added before agricultural areas removed)

EPC: Field Data_EPC.xlsx

FP_WBJ_EPC.shp Buffered (10m) floodplain polygon

HWA: Field Data_HWA.xlsx

FP_HWA_10m.shp Buffered (10m) floodplain polygon

LOR: Field Data_LOR.xlsx some logjams measured by piece with diameter and length of large wood, some with the box method. The box method calculates volume of the logjam from approximate length (L) x width (W) x depth (D) of the logjam multiplied by (1 Porosity (P%)), instead of measuring all of the pieces of large wood individually. Porosity is measured visually and represents the percentage of the rectangular prism, or box, that is made up of air space.

FP_LOR_10m.shp Buffered (10m) floodplain polygon

NSV: No field data collected

FP_NSV_10m.shp Buffered (10m) floodplain polygon

RTCO: Field Data_RTCO.xlsx

FP_RTCO_10m.shp Buffered (10m) floodplain polygon

SDWA: Field Data_ SDWA.xlsx some logjams just included as individual pieces of wood with diameter and one with the box method. The box method calculates volume of the logjam from approximate length (L) x width (W) x depth (D) of the logjam multiplied by (1 Porosity (P%)), instead of measuring all of the pieces of large wood individually. Porosity is measured visually and represents the percentage of the rectangular prism, or box, that is made up of air space.

FP_ SDWA _10m.shp Buffered (10m) floodplain polygon

SMT: Field Data_SMT.xlsx Class and Sediment Core data collected in 2022, Large Wood data collected in 2017

FP_SMT_10m.shp Buffered (10m) floodplain polygon (buffer added before high elevation non-floodplain surfaces removed)

SOK: Field Data_SOK.xlsx

FP_SOK_10m.shp Buffered (10m) floodplain polygon

WBJ: Field Data_WBJ.xlsx

FP_WBJ_10m.shp Buffered (10m) floodplain polygon

Contact Information

Emily Iskin, emilyiskin@boisestate.edu
Ellen Wohl, ellen.wohl@colostate.edu

Data Citation

Iskin, E.P. & Wohl, E. (2023). Data associated with Beyond the Case Study: Characterizing Natural Floodplain Heterogeneity in the United States, Dryad, Dataset. https://doi.org/10.5061/dryad.0k6djhb4q

Related Work

Iskin, E.P. & Wohl, E. (2023). Beyond the Case Study: Characterizing Natural Floodplain Heterogeneity in the United States, Water Resources Research, e2023WR035162. https://doi.org/10.1029/2023WR035162