USDA Forest Service

Pacific Southwest Research Station

Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
United States Department of Agriculture Forest Service. USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.

Research Topics Ecosystem Processes

Sierra Nevada Ecosystems

Forest Function and Health

Our current work in this area is focused on addressing this question using a singular but comprehensive objective: What are fire and thinning effects on forest structure, composition, and function, and how do these effects change across spatial and temporal scales: from stand to watershed to landscapes, over time? The Sierra Nevada Research Center has research projects associated with each of these spatial scales. Our projects are organized by examining restoration effects on (a) structure and composition, and (b) function at three different spatial scales.

blue arrrowSnags (Standing Dead Trees) in the Forest-Causes of Tree Mortality, Differences in Decay Trajectories, Interactions with Fungi, Insects, and Vertebrates, and Spatio-temporal Variation of Snags in Landscapes.

blue arrrowPlumas/Lassen Administrative Study - Fire and Fuels Management, Landscape Dynamics, and Fish and Wildlife Resources: Study Design for Integrated Research in the Northern Sierra Nevada

blue arrrowPlumas/Lassen Administrative Study Vegetation Module
Forest Restoration in the Northern Sierra Nevada: Impacts on Structure, Fire Climate, and Ecosystem Resilience

Subproblem 1: Forest Health and Function at the Stand-scale

photo of forestResearch on forest structure and function at the stand-level is the foundation upon which an understanding of watershed processes and landscape patterns must be built. Research at the stand scale, while still challenging, is achievable with conventional experimental design and statistical analytical approaches. Key processes at the stand level are nutrient cycling, microclimate conditions, changes in food webs, and respiration and decomposition rates. Our research areas that address this scale are geographically distributed between Blacks Mountain Experimental Forest (E.F.) on the Lassen National Forest, the Plumas National Forest, and the Kings River Project and Teakettle Experimental Forest on the Sierra National Forest, thus covering northern, central and southern Sierra locations.

blue arrrowSmall mammal and truffle response to burning in mixed-conifer forest

blue arrrowTeakettle Ecosystem Study: Fire and thinning effects on mixed conifer ecosystem structure and function

Subproblem 2: Forest Health and Function at the Watershed-scale

Water is probably the most valuable commodity yielded by the Sierra Nevada mountain range and the most limiting resource on plant growth, directly affecting forest function and health. Key processes at this scale are water infiltration and runoff rates, sediment transport, and stream nutrients. Watersheds bind stand-level ecosystems by sharing this common transport medium.

Subproblem 3: Forest Health and Function over large landscape-scale.

photo of forest fireForest management and restoration requires large-scale planning andimplementation. Certainly one of the largest scales for applying restoration is the 10 year plan for a National Forest typically encompassing up to several million acres. Processes at this scale include wildfire behavior and the effects of habitat configuration and fragmentation on wildlife population dynamics. Research has rarely been conducted at this scale because of design, expense, and implementation problems. SNRC is working closely with the Plumas and Lassen National Forests to assess the response of an array of important response variables (e.g. spotted owls, fire behavior) to fire and thinning restoration treatments on more than one million acres.

blue arrrowThe influence of Activities, Events, and Landscape Character on Composition, Structure and Landscape Pattern of Historic Forests