Mapping irrigated cropland from Landsat data for determination of water use from the High Plains Aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

Content Provider	Semantic Scholar
Author	Thelin, Gail P. Heimes, Frederick J.
Copyright Year	1987
Abstract	Landsat multispectral-scanner data have been used to map irrigated cropland for determination of water use from the High Plains aquifer. Water-use estimates have provided one critical element in a groundwater flow model being developed by the U.S. Geological Survey. Information on irrigeited acreage and water use is needed to evaluate the effects of agricultural development on the High Plains aquifer. The High Plains aquifer is the primary source of water for one of the Nation's major agricultural areas covering about 174,000 square miles within parts of eight States. Several methods for determining irrigated acreage were evaluated. Digital analysis of Landsat data proved to be the most suitable approach and was used in a two-phase effort to map irrigated acreage for both the 1978 and 1980 growing seasons. The first phase, a test of analysis procedures, used 1978 Landsat data to map the majority of the High Plains. The test used a cluster-analysis technique to derive acreage estimates of irrigated cropland, nonirrigated cropland, and rangeland using 35 summer Landsat scenes. Based on the first-phase test results, several modifications were made to streamline and improve analysis techniques for the second-phase mapping of irrigated cropland using 1980 Landsat data. The analysis of 1980 data used a ratio technique to analyze the 59 spring and summer Landsat scenes required to provide acreage estimates for the major irrigated crops on the High Plains. Acreage estimates of irrigated cropland, nonirrigated cropland, and rangeland were aggregated to form a data base containing about 174,000 grid cells measuring 1 minute of latitude by 1 minute of longitude. Percentages for each land-use type were calculated and combined with sampled irrigation-application rates to compute estimates of irrigation water use for the ground-water flow model. An estimated 17,980,000 acre-feet of ground water was pumped from the High Plains aquifer during the 1980 growing season to irrigate 13,700,000 acres. To verify the reliability of the irrigated-acreage estimates used to calculate water use, an accuracy evaluation was conducted for the 1980 mapping of irrigated cropland using a multistage random-sampling method. The statistical evaluation confirmed that Landsat data and simple analysis techniques can provide an efficient tool for mapping irrigated cropland for the High Plains. However, availability of suitable Landsat scenes is required to provide a complete inventory of irrigated cropland. The techniques used to map irrigated cropland for the High Plains should be applicable to similar areas of the Western United States. INTRODUCTION The U.S. Geological Survey began a regional study of the High Plains aquifer in 1978 as part of its Regional Aquifer-System Analysis (RASA) program. The general purpose of the High Plains RASA is to provide (1) hydrologic information needed to evaluate the effects of continued ground-water development and (2) groundwater flow models to evaluate aquifer response to changes in ground-water development (Weeks, 1978). Comprehensive information on ground-water withdrawals for irrigation is essential in testing and incorporating the ground-water flow model as a tool for evaluation of management alternatives. A variety of reported information was available for development and testing of the ground-water flow model. However, rapid changes in cropping practices and irrigation techniques have occurred in recent years on the High Plains. Consequently, timely information on ground-water use for irrigation is needed to ensure that changing trends in water use are incorporated in the model. This report describes the analysis of Landsat-satellite data to derive acreage estimates of irrigated cropland. Irrigatedcropland acreage data were combined with sampled information on irrigation withdrawals to estimate ground-water use for irrigation on the High Plains. The High Plains includes an area of about 174,000 mi2 east of the Rocky Mountains in the southern part of the Great Plains. Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming are included in the High Plains as shown in figure 1. Ground water withdrawn from the aquifer is the principal source of water for this important agricultural area. The High Plains aquifer is the shallowest and most abundant source of ground water
File Format	PDF HTM / HTML
DOI	10.3133/pp1400c
Alternate Webpage(s)	https://pubs.usgs.gov/pp/1400c/report.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article