Land suitability analysis for the upper Gila River watershed
Introduction
Efficient and thoughtful use of land is an important step in managing and developing any area, especially one as vast as that of the upper Gila River watershed in Arizona and New Mexico. Much of the land in this watershed is managed by federal agencies including the U.S. Forest Service and the U.S. Bureau of Land Management. These agencies are required to assess the suitability of land and other resources under their jurisdiction for future possible uses. In addition, the State of Arizona affords an opportunity to develop sound planning at a large scale in response to the citizen-mandated Growing Smarter Initiative. This 1998 law proposes to “strengthen the ability of Arizona’s communities to plan for growth, acquire and preserve open space, and develop strategies to comprehensively address growth-related pressures” (Arizona Department of Commerce, 1998a, Arizona Department of Commerce, 1998b). As a result, Arizona counties and cities are now required to prepare general and comprehensive plans that incorporate numerous elements including an analysis of future needs and policies for open space, coordinated growth, and future development strategies.
These statewide policies take a broad regional perspective, but also examine a more narrow focus within the constraints of counties, cities, and towns. By implementing such a comprehensive planning vision, it is hoped that effects will be seen in various urban and rural communities throughout the state. In order to determine the most desirable direction for future development, the suitability for various land uses should be explored in order to direct growth to the most appropriate places.
One approach to establishing appropriate land-use criteria is the construction of suitability analyses. Land suitability analysis is the process of determining the fitness of a given tract of land for a defined use (Hopkins, 1977, Steiner, 1983). Initially, this tool was developed as a means for planners to relate spatially independent factors within the environment and, consequently, provide a more holistic view of their interactions. Suitability analysis techniques integrate three factors of an area: location, development activities, and biophysical/environmental processes (Miller et al., 1998). These techniques enable planners and local decision-makers to analyze interactions in various ways. Such analysis can help elected officials and land managers make decisions and establish policies regarding the use of particular areas of land.
Even though land suitability analysis is a well-known tool among planners and landscape architects, there are relatively few documented examples where a process used in one place has been transferred or adapted in another. (The few examples include the work of McHarg, 1969 and Lyle, 1985). This paper provides such an example, as will be explained in Section 3.
Suitability techniques are essential for informed decision-making. The most important decision an analyst makes when using this tool is the determination of how relative values, or weights, are to be given to two or more combined factors. Factors are simply characteristics of land that are grouped as attributes (Pease and Coughlin, 1996). Slope, soil type, aquifer recharge areas, floodplains, scenic areas, and wildlife habitats are examples of such factors. Once chosen, factors are weighted; that is, they are given a numeric value that indicates their relative importance in determining the suitability of an activity in a given area. Although these judgements introduce an element of subjectivity to the analysis, weights are based on sound factual information for what the land is or is not intrinsically capable of supporting. Because these values are explicit to the given area and represent economic, environmental, and public health dimensions, weighting tries to represent the interplay among factors in a landscape.
Since watersheds consist of essential natural resources, their planning requires forethought and careful consideration. A watershed-scale suitability analysis can help local officials and private businesses avoid unnecessary expenditures while protecting valuable environmental amenities.
Section snippets
Upper Gila River watershed
The upper Gila River watershed is an area characterized by fertile valleys, mountainous terrain, and an important waterway, the Gila River (Cohen et al., 1997). The watershed basin created by the river encompasses over 62,160 km2 and includes portions of both Arizona and New Mexico. The watershed begins ≈321 km east of Phoenix, AZ, and ≈483 km west of Santa Fe, NM. The Fort Apache and San Carlos Indian Reservations determine the western boundary for the upper watershed while the eastern boundary
Methods
Developing an overall suitability analysis for a region as large as the upper Gila River watershed would be problematic if not unrealistic. In response, the project team designed a framework for suitability analysis for four specific land uses. As determined by members of the San Carlos/Safford/Duncan Non-Point Source Management Committee, the following land uses were examined: low-density housing, commercial development, industrial development, and recreation.
A previous analysis was conducted
Results
The Asotin County method was adapted for the four land uses identified by the local ‘Gila-monster’ committee. The results of that adaptation are reported below. Initially, a map was going to be produced for each land use. However, because of the scale of the watershed and incomplete data, maps were not produced. Local officials found the framework matrices less ‘prescriptive looking’ and, thus, potentially more effective for their planning efforts.
Discussion
The framework for a suitability analysis rests heavily on the data available. Comprehensive information needs to be available for each of the factors applied in the analysis. This information includes accurate floodplain mapping, delineated city boundaries, current zoning restrictions, and current infrastructure assessments. Demographic information such as population density and market area analyses becomes important as a means of evaluating the relative weight of factors. Comprehensive soil,
Conclusion
For Arizona counties with a population of >100,000 people, the Growing Smarter legislation requires that comprehensive plans must address land uses. These land-use elements need to address the general distribution and location for housing, commerce, industry, agriculture, recreation, education, public buildings and grounds, and open space (Arizona Department of Commerce, 1998a). Furthermore, the legislation requires that all zoning and rezoning ordinances need to be consistent with the adopted
Acknowledgements
We appreciate the support and guidance of Russ Smith, Jerry Barney, and Pete Brawley through the process of this work. Other members of the San Carlos/Safford/Duncan Non-Point Source Management Committee as well as Arizona Department of Environmental Quality staff were also quite helpful. Several Arizona State University environmental planning students contributed to this research including Scott Smith, Liesl Dommisse, Zitao Fang, Kristen Keener, Donna Stevens, Matthew Bucchin, and Shahin
Frederick Steiner is Professor and Director of the Arizona State University (ASU) School of Planning and Landscape Architecture. In 1998, he was a Rome Prize fellow in historic preservation and conservation at the American Academy in Rome and was a Fulbright scholar at Wageningen University, The Netherlands, in 1980. He received his Ph.D., M.A., and Master of Regional Planning degrees from the University of Pennsylvania and Master of Community Planning and B.S. in Design degrees from the
References (13)
- et al.
An approach for greenway suitability analysis
Landsc. Urban Plann.
(1998) - Arizona Department of Commerce, 1998a. Growing Smarter Legislation: A Summary for Counties. Arizona Department of...
- Arizona Department of Commerce, 1998b. Growing Smarter Legislation: A Summary for Cities and Towns. Arizona Department...
- Richard, B., Benson, D., Brunton, D., Johnson, K.L., Knowles, J., Michalovic, J., et al. 1978. Asotin County Ecological...
- City of Safford, 1996. City of Safford Planning & Zoning Ordinance, Resolution No. 96-1128. City of Safford,...
- Cohen, J., Dahnad, S., Dommisse, L., Fang, Z., Keener, K., Smith, S., Stevens, D., 1997. Upper Gila River Watershed...
Cited by (137)
Estimation of the effectiveness of multi-criteria decision analysis and machine learning approaches for agricultural land capability in Gangarampur Subdivision, Eastern India
2022, Artificial Intelligence in GeosciencesPyLUSAT: An open-source Python toolkit for GIS-based land use suitability analysis
2022, Environmental Modelling and SoftwareCitation Excerpt :For example, these polygons can be property parcel data or an output of a series of GIS operations using multiple datasets, such as the Integrated Decision Units (IDUs) (Bolte et al., 2007; Wu et al., 2015). The classic suitability analysis framework contains three steps: (1) evaluate land units based on identified criteria, (2) transform the measurements to a uniform suitability scale, and (3) combine the results to generate a single suitability score for each land unit (Steiner et al., 2000; Marull et al., 2007). The three tasks of suitability analysis can be carried out respectively by the three types of PyLUSAT functions: geospatial functions, transformation functions, and aggregation functions.
A multi-criteria land suitability assessment of field allocation decisions for switchgrass
2022, Ecological IndicatorsImproving integrated environmental zoning from the perspective of logic scoring of preference and comparative advantage: A case study of Liangjiang New Area, China
2021, Journal of Cleaner ProductionCitation Excerpt :Finally, numerical processing procedures are formulated to integrate the results of UDLS and RECC, including evaluating CARECC, numerical processing of the results of the UDLS evaluation, and overlaying. UDLS analysis evolved from the ecological inventory process (McHarg, 1969) and the transparent overlay process (Steiner et al., 2000). Due to advances in land assessment methods, the ecological inventory process gradually evolved from including only physical factors to including ecological and economic-cultural factors (McHarg, 1981).
Frederick Steiner is Professor and Director of the Arizona State University (ASU) School of Planning and Landscape Architecture. In 1998, he was a Rome Prize fellow in historic preservation and conservation at the American Academy in Rome and was a Fulbright scholar at Wageningen University, The Netherlands, in 1980. He received his Ph.D., M.A., and Master of Regional Planning degrees from the University of Pennsylvania and Master of Community Planning and B.S. in Design degrees from the University of Cincinnati. Professor Steiner is the author of The Living Landscape (second Edition, 2000, McGraw–Hill) and co-editor, with Ian McHarg, of To Heal the Earth (1998, Island Press). With Laurel McSherry, he received a grant from the Arizona Department of Environmental Quality which provided the basis for this paper.
Laurel McSherry is Associate Professor of the ASU School of Planning and Landscape Architecture. In 1999–2000, she was a Rome Prize fellow in landscape architecture at the American Academy in Rome. She received her Master of Landscape Architecture from Harvard University and her undergraduate degree in landscape architecture from Rutgers University. She was the principal investigator of the research project, funded by the Arizona Department of Environmental Quality, on which this paper is based.
Jill Cohen was a research assistant in the ASU School of Planning and Landscape Architecture. She pursued both a master of environmental planning and an M.S. in environment resources. Ms. Cohen earned her B.S. in wildlife and fisheries biology from the University of California-Davis.