Assessment of Top Down and Bottom Up Controls on Fire Regimes and Vegetation Abundance and Distribution Patterns in the Chihuahuan Desert Borderlands: A Hierarchical Approach. Final Report to the Joint Fire Science Program, Project No. 03-3-3-13

摘要

The goal of the study was to quantify historical fire regimes, climate forcing of fire events, plant population dynamics, and fuel abundance and distribution patterns in the Chihuahuan Desert Borderlands. The results provide information about recent changes in fire regimes, forest structure and species composition as a result of fire exclusion (grazing) and direct fire suppression. The study area straddled the US-Mexico border, and included Big Bend National Park (BIBE), and The Davis Mountains Preserve of The Nature Conservancy (DMTNC) in Texas, and the Maderas del Carmen Protected Area (MCPA) in Coahuila, Mexico. These preserves were chosen for the study because they comprise a regional-scale representation of the variation in fire regime characteristics and forest vegetation types in a region where no fire or forest inventory data existed. Furthermore, they represented understudied pinyon-juniper and pine-oak vegetation assemblages in southwestern North America. Each of the three preserves is run by a different management agency, which enabled the sharing of experiences across agency boundaries, and provided a large-scale perspective of fire-climate-vegetation interactions in this region. Data from the study provide critically needed reference conditions and targets for ecological forest restoration to lower the risk of future high intensity fire.