Dataset DOI: 10.5061/dryad.tb2rbp0f9

Description of the data and file structure

This dataset characterizes patterns of evapotranspiration, impacts of water conservation, and hydropedological characteristics of fields in the West Slope Region, Colorado, USA. A total of 392 agricultural field boundaries where water conservation activities occurred in the 2016-2024 period were hand digitized, based on available aerial imagery and paper maps. Within these fields, we randomly sampled 5,275 points. Each point was joined to elevation values from 30 meter Shuttle Radar Topography Mission (SRTM) coverages, classification keys from the gridded National Soil Survey Geographic Database (gNATSGO), and field centroids from the Colorado Decision Support System (CDSS) Irrigated Lands Geodatabase. All work with spatial data was completed in QGIS. Sampled points were treated as the centroids for delineating Agricultural Hydropedological Units (AHUs). AHUs were generated with 30, 60, 90, 120, and 180 meter diameters around these centroids, producing a total of 21,281 individual polygons of varying area. The AHUs were the fundamental spatial unit used to extract times series of evapotranspiration, normalized difference vegetation index (NDVI), and precipitation from the OpenET API.

Files and variables

File: AHU_centroids.csv

Description: Table of randomly sampled centroid points used to delineate AHUs.

Variables

• ahu_centroid (PK): Unique identifier for AHU centroids
• field_id (FK): Unique identifier for delineated fields
• utm13N_x: Easting in the UTM 13N projection (meters)
• utm13N_y: Northing in the UTM 13N projection (meters)
• elev_m: Elevation (meters) sampled form SRTM 30 m data coverage.
• mukey (FK): gNATSGO map unit key.
• PARCEL_ID (FK): Unique identifier for the mapped fields in the CDSS Irrigated Lands Geodatabase.
• MASTER_ID (FK): Companion identifier for PARCEL_ID.

File: AHUs.csv

Description: Table of unique AHU unique identifiers.

Variables

• ahu_id (PK): Unique identifier for individual AHUs.
• ahu_centroid (FK): Unique identifier of the ahu_centroid used to generated the AHU.
• ahu_diameter_m: Diameter of the AHU (meters).

File: AHU_et.csv

Description: Table containing daily time series of ET, NDVI, and precipitation for the 2016-2024 growing seasons for each of the AHUs. Data was extracted from the OpenET API (https://openet.gitbook.io/docs/). OpenET granted a CC-BY-4.0 license waiver for this dataset so that it could be published to this repository.

Variables

• ahu_id (FK): Unique identifier for individual AHUs
• time: The date of observation.
• et: Evaoptranspiration computed by the eeMETRIC model (mm)
• ndvi: Normalized difference vegetation index
• eto: Grass reference ET (mm)
• etr: Alfalfa reference ET (mm)
• pr: Precipitation depth estimated by gridMET (mm)

File: fields.csv

Description: Table containing information about conservation activities performed on the set of 392 fields in the West Slope region of Colorado, USA.

Variables

• field_id (PK): Unique identifier for delineated fields
• field_group: Grouping variable for fields.
• field_code: Grouping variable for fields.
• hectares: Computed area of the field (hectares).
• conservation_program: The name of the conservation program that the field participated in. Can be used to cross reference technical reports, journal articles, or contracts available in the Colorado Division of Natural Resources Laserfiche (https://dwr.colorado.gov/imaged-documents).
• conservation_year_1: The first year during which water conservation activities took place. Missing information indicated as NA.
• conservation_activity_1: The type of water conservation practice enacted in conservation_year_1. Missing information indicated as NA.
• curtailment_start_date_1: The start of irrigation water curtailment during conservation_year_1. Missing information indicated as NA.
• curtailment_end_date_1:The end of irrigation water curtailment during conservation_year_1. Missing information indicated as NA.
• conservation_year_2: The second year during which water conservation activities took place. Variable assigned NA for fields where conservation measures were only enacted for a single year.
• conservation_activity_2: The type of water conservation practice enacted in conservation_year_2. Variable assigned NA for fields where conservation measures were only enacted for a single year.
• curtailment_start_date_2: The start of irrigation water curtailment during conservation_year_2. Variable assigned NA for fields where conservation measures were only enacted for a single year.
• curtailment_end_date_2: The end of irrigation water curtailment during conservation_year_2. Variable assigned NA for fields where conservation measures were only enacted for a single year.
• conservation_agreement_crop: The type of crop under irrigation noted in agreements contained in contracts, reports, and other paper records of conservation activities. Values here can be compared to the more complete listing of crop_type values included in the cdss_centroids.csv table. Variable assigned a value of NA for instances where additional information about crop type was not available. 

File: field_et.csv

Description: Table containing daily time series of ET, NDVI, and precipitation for the 2016-2024 growing seasons for each of the delineated fields. Data was extracted from the OpenET API (https://openet.gitbook.io/docs/). OpenET granted a CC-BY-4.0 license waiver for this dataset so that it could be published to this repository.

Variables

• field_id (FK): Unique identifier for individual fields
• time: The date of observation.
• et: Evaoptranspiration computed by the eeMETRIC model (mm)
• ndvi: Normalized difference vegetation index
• eto: Grass reference ET (mm)
• etr: Alfalfa reference ET (mm)
• pr: Precipitation depth estimated by gridMET (mm)

File: gNATSGO.csv

Description: Table containing Map Unit Aggregate Attributes (muaggatt) keys from gNATSGO.

Variables

• See the gNATSGO documentation for a complete description of table variables (https://www.nrcs.usda.gov/resources/data-and-reports/gridded-national-soil-survey-geographic-database-gnatsgo#metadata). 
• Non-applicable cells populated with NA values.

File: cdss_centroids.csv

Description: Table containing information from the CDSS Irrigated Lands Geodatabase for mapped agricultural fields across the West Slope region of Colorado. See the CDSS GIS data pages for more information (https://cdss.colorado.gov/gis-data/gis-data-by-category).

Variables

• fid (PK): Unique feature ID
• OBJECTID: CDSS object ID
• MAPPED_YEAR: The year that the field was mapped for revised in CDSS
• WATER_DIVISION: The Water Division where the field is located
• WATER_DISTRICT: The Water District where the field is located
• PARCEL_ID (FK): A unique parcel identification number for the field
• MASTER_ID (FK): A companion identification number to the PARCEL_ID
• CROP_TYPE: The CDSS mapped crop type
• CROP_SOURCE: The source of the crop mapping/assignment
• PERENNIAL: Perennial crop flag (Yes/No)
• IRRIG_TYPE: The CDSS mapped irrigation type
• ACRES: The CDSS computed field acreage
• SW_WDID1: The Well and Structure Identification Number (WDID) associated with the field's first surface water right
• SW_WDID2: The WDID associated with the field's second surface water right. Variable assigned NA in cases where no such water right is recorded
• SW_WDID3: The WDID associated with the field's third surface water right. Variable assigned NA in cases where no such water right is recorded
• SW_WDID4: The WDID associated with the field's fourth surface water right. Variable assigned NA in cases where no such water right is recorded
• SW_WDID5: The WDID associated with the field's fifth surface water right. Variable assigned NA in cases where no such water right is recorded
• COUNTY: The county where the field is located
• ELEV_m: Elevation (meters) sampled form SRTM 30 m data coverage. This is not an attribute from the CDSS Irrigated Lands Geodatabase
• mukey (FK): gNATSGO map unit key. This is not an attribute from the CDSS Irrigated Lands Geodatabase

File: cdss_westslope_field_centroids.gpkg

Description: Geopackage containing a point layer of centroids from agricultural field polygons included in the CDSS Irrigated Lands Geodatabase. Data may be used sample additional environmental variables and join them back to the other tables.

File: fields.gpkg

Description: Geopackage containing a polygon layer of delineated fields represented in the fields.csv file.

File: ahu_centroids.gpkg

Description: Geopackage containing a point layer of AHU centroids. Layer may be used to sample additional environmental variables and join them back to the other tables.

Access information

Data was derived from the following sources:

• OpenET (https://doi.org/10.1111/1752-1688.12956). OpenET granted a CC-BY-4.0 license waiver for this dataset so that it could be published to this repository.
• Colorado Decision Support System Irrigated Lands Geodatabase (https://cdss.colorado.gov/gis-data/gis-data-by-category)
• Gridded National Soil Survey Geographic Database (https://www.nrcs.usda.gov/resources/data-and-reports/gridded-national-soil-survey-geographic-database-gnatsgo#metadata)
• Shuttle Radar Topography Mission (SRTM) (https://www.earthdata.nasa.gov/data/instruments/srtm)