Session Information
| Session | Poster Session | | Date | Monday (2008-04-07) | | Time | 5:00 PM - 7:00 PM | | Room | Grand Terrace |
Presentation Information
| Presenter | Zach Nelson | | Title | Spatial simulation of historical landscape patterns in mountain sagebrush dominated landscapes of Utah and Nevada | | Affiliation | University of Nevada Reno | | Authors | Zach Nelson, Peter Weisberg, Stanley Kitchen, Dongwook Ko | | Keywords | Fire regime, Landscape dynamics, Sagebrush, Spatial simulation | | Presentation Type | Poster | Abstract:
Knowledge of past fire regimes associated with mountain sagebrush-dominated landscapes is inadequate for accurate assessment of current departures from historic conditions and scientifically-based fire planning by land managers. Dendrochronological fire history methods utilizing fire scars on “proxy trees” at ecotonal boundaries may be inappropriate for understanding fire regimes of shrub-dominated ecosystems. Fire regime characterizations for mountain sagebrush vegetation are commonly developed despite a paucity of empirical data and are often controversial. However, an understanding of historical mountain sagebrush fire regimes is essential for developing reference conditions for spatiotemporal dynamics of plant community types and seral stages, as are needed for landscape restoration and wildlife habitat conservation.
We present a conceptual framework and parsimonious model for relating patch dynamics of mountain shrub communities to historical fire regimes (fire frequency, extent, distribution of severity classes, and spatial pattern), utilizing known life history traits of shrub species. An uncertainty analysis, based on a meta-analysis of existing studies, is used to quantify feasible outcomes for landscape structure and seral dynamics given alternative fire regime scenarios. We use empirically derived estimates of fire frequency and rate of woody species recovery and tree invasion from the Great Basin, upper Colorado Plateau and intervening mountains and highlands as model input. Our results quantify the ranges of fire regime parameter values that are compatible with long-term persistence of mountain sagebrush community types, as well as the variation in landscape pattern across this range. |
|