Document


Title

Watershed modeling on fire management planning in the northern Rocky Mountains
Document Type: Book
Author(s): D. F. Potts; D. L. Peterson; H. R. Zuuring
Publication Year: 1985

Cataloging Information

Keyword(s):
  • Abies spp.
  • cover
  • cover type conversion
  • ecosystem dynamics
  • erosion
  • evapotranspiration
  • fire intensity
  • fire management
  • fire size
  • forest management
  • hydrology
  • land management
  • Larix occidentalis
  • logging
  • mountains
  • national forests
  • Picea
  • Picea sitchensis
  • Pinus contorta
  • Pinus monticola
  • Pinus ponderosa
  • post fire recovery
  • Pseudotsuga menziesii
  • roads
  • salvage
  • sedimentation
  • seedlings
  • statistical analysis
  • streamflow
  • Tsuga
  • water
  • water quality
  • watershed management
  • watersheds
  • wildfires
Region(s):
Record Maintained By:
Record Last Modified: August 6, 2018
FRAMES Record Number: 37560
Tall Timbers Record Number: 12041
TTRS Location Status: In-file
TTRS Call Number: A13.78:PSW-177
TTRS Abstract Status: Fair use, Okay, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.

Description

Water yield and sediment production almost always increase after wildfire has destroyed vegetative cover. The value of water generally is not as much appreciated in the water-rich northern Rocky Mountains as it is elsewhere. Increased water yield becomes economically beneficial, however, when its potential for consumptive and nonconsumptive uses is realized. Whether the effects of increased sedimentation are esthetic, biological, physical, or economic, they are usually detrimental. Fire management programs for the National Forests are required to be an integral part of land management planning. Managers must be able to estimate postfire changes in resource outputs and values within the context of a particular fire management program. The quantity of additional water and sediment produced is a function of fire characteristics and site-specific factors: vegetation. climate, and physical characteristics. Planning. however, requires a broad resolution analysis system. Therefore, site-specific water and sediment yield models were adapted to meet broad resolution planning objectives. In a study of fire-induced changes in watersheds in the northern Rocky Mountains, two simulation models were applied. Procedures from Water Resources Evaluation of Nonpoint Silvicultural Sources (WRENSS) estimated water yield, and a closely related model estimated four major components of sediment yield--natural sediment, sediment from management induced mass erosion, sediment from management-induced surface erosion, and sediment delivery. Computerized versions of the models were used to estimate postfire water yield for 18 possible management cases and postfire sediment yield for 81 cases -Net value change of water resources was calculated with in vestment analysis. Water yield was most affected by basal area loss; the greater the loss, the greater the relative increase in water yield. Water yield increased over natural yield, however, only if fire or salvage logging or both removed greater than 50 percent of stand basal area. Fire had a relatively small effect on sediment production in most cases. Increases were relatively large only for fires with large areas. Natural sediment yield increased more than did management-induced sediment yield. Postfire sediment increases were severe only on sites with steep slopes and large fires Increased water yields resulted in a beneficial net value change for all cases. Benefits were substantial (up to $33.42 per acre or $80.21 per hectare) in some cases and were less than $5 per acre ($12 per hectare) only in some cases with 50 percent basal area loss. Net value change was increasingly negative as basal area -loss increased. Net value change for sediment yield was detrimental for all cases, but was always less than $.01 per acre ($.02 per hectare).

Citation:
Potts, D. F., D. L. Peterson, and H. R. Zuuring. 1985. Watershed modeling on fire management planning in the northern Rocky Mountains. Research Paper PSW-177. Berkeley, CA, USDA Forest Service, Pacific Southwest Forest and Range Experiment Station.