Issue Date
1984-11-01Keywords
vegetation yieldswater yield
Soil Water Models
Hydrologic Cycle
mathematical models
simulation
Ekalaka Rangeland Hydrology and Yield Model
ERHYM
Soil Plant Air Water Model
SPAW
water storage
Reservoir
evaluation
rangelands
soil profiles
Metadata
Show full item recordCitation
Cooley, K. R., & Robertson, D. C. (1984). Evaluating soil water models on western rangelands. Journal of Range Management, 37(6), 529-534.Publisher
Society for Range ManagementJournal
Journal of Range ManagementDOI
10.2307/3898852Additional Links
https://rangelands.org/Abstract
The soil profile is an important water storage reservoir within the hydrologic cycle. An understanding of the factors affecting daily soil water status is necessary to increase or modify vegetation or water yields. Many mathematical simulation models have been developed to assess soil water status, but none were found that were specifically developed for use on Western rangelands. The purpose of this report was to test soil water models that appeared to be sufficiently general for adaption to rangeland conditions, to determine if they could provide adequate results, and the level of sophistication required. The 2 models selected for evaluation were the Ekalaka Rangeland Hydrology and Yield Model (ERHYM) developed for use during the growing season on grasslands of the northern Great Plains, and the Soil-Plant-Air-Water model (SPAW), which was developed for use with cultivated crops in the Midwest. Results indicated that both models could be adapted to produce adequate soil water information under rangeland conditions of southwestern Idaho. Overall, the somewhat simpler ERHYM model produced results more closely aligned to observed values than did SPAW. The lack of a snow accumulation and melt routine in SPAW (which could be added) appeared to be the main source of observed differences. These differences were a function of timing rather than a difference in total soil water at the end of each year, where results for the 2 models were very similar.Type
textArticle
Language
enISSN
0022-409Xae974a485f413a2113503eed53cd6c53
10.2307/3898852
Scopus Count
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