USDA Forest Service

Pacific Northwest Research Station

Pacific Northwest Research Station
1220 SW 3rd Ave.
Portland, OR 97204

(503) 808-2100

US Forest Service

2009 Science Accomplishments Report > Ecological Process & Function Program Accomplishments >

Key Accomplishments of the Ecological Process and Function Program in 2009

Program Mission

The mission of the Ecological Process and Function Program (EPF) is to advance and communicate knowledge of fundamental ecological processes and their interactions at multiple scales, and to develop applications of such knowledge that enable improved management of ecosystems and resources.


Research Problem Statements

Problem 1: How does the biophysical environment influence the function and properties of ecosystems, ecological communities, species, populations, and organisms?

Problem 2: What are the potential influences of climate change on ecosystem
attributes, patterns, ecological processes, and their interactions?

Problem 3: How do disturbances influence ecological patterns and processes, and
how do disturbances and ecological processes interact to determine the overall
function, attributes, and dynamics of ecosystems?

Problem 4: What are the determinants of ecological status and trends of biota and

You can control the level of detail you receive by expanding or collapsing the content using the [+] and [-] buttons.

Collapse All | Expand All


Key Findings

click to expand/collapse.Groundwater will be major source of summer streamflow in Western U.S.

Blue River, H.J. Andrews Experimental ForestPrior efforts to model streamflow trends, and hence the availability of water, under future climate scenarios in the Western United States focused on snowpack dynamics. But snowpack is only one source of water. Station scientists found that groundwater dynamics exert a comparable, or even larger, control on future streamflow regimes than does snowpack. Different landscapes will have widely different responses to the same climate warming. Regions of the West with primarily groundwater sources will continue to have streamflow under climate warming, in contrast to areas served exclusively by snowpack, such as the southern Sierras in California. However, these same groundwater regions display maximum sensitivity to warming climate and will lose a significant proportion of their flow volumes, perhaps leading to unanticipated consequences for water quantity and aquatic habitat. Public water and energy utilities, such as the Eugene Water and Electric Board, are incorporating these findings with long-range management plans and strategies being developed by public water and energy utilities.

Contact: Gordon E. Grant,, Ecological Process and Function Program

Partner: University of California at Santa Barbara


click to expand/collapse.Nationwide study finds similarities, differences in stream chemistry responses to harvest and other disturbances

Forests provide high-quality water for downstream and instream uses.Stream chemistry is a major water quality parameter and responds to forest harvest and other disturbances to forest cover.
Forest managers need to be able to predict how forest harvest and other disturbanceswill affect water quality to meet federal and state Clean Water Act guidelines. To help provide this information, station scientists are reexamining long-term stream biogeochemistry data collected before and after forest harvest and thinning from gauged basins at the H.J. Andrews Experimental Forest to quantify relationships between amount and type of harvest and instream responses. Thus far, they have observed short-term increases of instream nitrate concentrations and export after clearcutting but little change with thinning.

Through collaborations with researchers at 10 other experimental forests across the country, the scientists are comparing the magnitude of responses among forest type and with differing nutrient limitations to harvest as well as to natural disturbances, including fire, hurricane, and insect infestations. Understanding the effects of disturbance, including forest management, on critical ecosystem processes facilitates the design of management options that minimize disruption of normal nutrient cycling. It also provides a foundation to predict responses in water quality and recovery time in forested watersheds following disturbances such as fire and insect infestation.

Contact: Sherri L. Johnson, sherrijohnson, Ecological Process and Function Program

Partners: National Council for Air and Stream Improvement; Oregon State University; University of Alaska-Fairbanks; University of New Hampshire; USDA Forest Service Northern Research Station, Pacific Southwest Research Station, Rocky Mountain Research Station, and Southern Research Station


Fire forecasting system accurately calculates area burned and costs for 2008

The station produces continuously updated 7-month forecasts of fire danger and drought for the conterminous United States using the MC1 Dynamic General Vegetation Model. In 2009, scientists worked to increase the spatial resolution of the fire forecasting system by more than two orders of magnitude, bringing the focus down from grid cells of 50 square kilometers (km) to 4 square km. A "hindcast" of acreage burned in 2008 at the increased resolution was just 2 percent below actual burned area reported by the National Interagency Fire Center.

Scientists also began providing output from their fire forecasting system to researchers at the Rocky Mountain Research Station for use in predicting total annual firefighting expenditures. Preliminary results show these forecast-based regression models are significantly better at predicting total seasonal expenditures than the professional judgment approach currently used at the National Interagency Fire Center. Actual total firefighting expenditures for the 2008 fire season were about $1.25 billion. The predicted expenditure based on the 50-km hindcast for 2008 was about $1.21 billion, or just 3 percent below observed. Nearly 200 land managers from various resource agencies receive monthly alerts about new fire forecasts posted on the Mapped Atmosphere-Plant-Soil System (MAPSS) Web site. In April, the 2009 seasonal forecast was presented to fire managers throughout the West.

Contact: James M. Lenihan;, Ecological Process and Function Program

Partners: National Interagency Coordination Center, Oregon State University

For more information: /pnw/mdr/mapss/fireforecasts/index.shtml


New prototypes provide advanced evaluations of wildfire danger

Federal land-management agencies responsible for managing forest fuels have been strongly criticized in recent years by Congress and oversight agencies for lacking a rational process for allocating funds for fuel treatment. To remedy this, since 2006, scientists have been using the Ecosystem Management Decision Support system to develop national level decisionsupport applications for fuel analysis and fuel-treatment planning for the Forest Service and U.S. Department of the Interior. This year, the project undertook advanced and comprehensive fuel evaluations at fine spatial scales. Separate prototypes were developed for the Pacific Northwest and western Montana. Both prototypes provide advanced evaluations of wildfire danger at the subwatershed scale (roughly 25,000 to 30,000 acres), drawing on data from the LANDFIRE Program, NASA, and other reliable agency sources. The new prototypes provide "wall-towall" evaluations of fire danger for all subwatersheds in a geographic region. These units can be correlated with a wide range of administrative units such as ranger districts, national forests, Bureau of Land Management districts, and national parks.

Contact: Keith M. Reynolds,, Paul Hessburg,, Ecological Process and Function Program

Partners: USDA Forest Service Fire and Aviation Management, Intermountain Research Station, Northern Region, and Pacific Northwest Region; USDI Bureau of Land Management, Oregon State Office


Lessons from Mount St. Helens applied to other volcanic regions

Mount St. Helens, a rich natural outdoor laboratory for 29 years, has yielded Mount Saint Helensnumerous lessons and insights that can be carried and applied to other volcanic landscapes throughout the world. Station scientists are sharing these insights with foreign governments and scientists to help develop studies in Chile and Alaska sites of intense volcanic disturbance in 2008 and 2009. They are also facilitating related learning opportunities for graduate students. In preparation for the 30th anniversary of the May 18, 1980, eruption, station scientists hosted photographers, writers, and filmmakers from numerous media outlets, including the National Geographic Society, New York Times, and NOVA. These articles and film will share findings about ecosystem response after volcanic eruption with the general public.

Contacts: Charlie Crisafulli, ccrisafulli, Land and Watershed Management Program; Fred Swanson,, Ecological Process and Function Program

Partners: Parque Pumalin; University of Alaska (Anchorage and Fairbanks); University Austral de Chile; University of Nevada-Las Vegas; U.S. Fish and Wildlife Service; U.S. Geological Survey (Cascades and Alaska Volcano Observatories)


New system yields climatechange simulations at 100-meter resolution
climate mapping at lower resolution800 meters Climate mapping at ultra-fine resolutions 80 meters

Increasing requirements for climatechange simulations at ultra-fine resolution has created the need for methods to downscale existing gridded climate data sets with resolution of about 1 kilometer to about 100 meters. This ultra-fine scale is needed to simulate the effects of climate change on ecosystems in regions with complex topography where the slope of the terrain and direction it faces creates microclimates based on differences in exposure to sunlight. To meet this need, station scientists and collaborators developed a GIS-based system for downscaling commonly available gridded climate data. The system was tested on existing grids of climate data for the Olympic Peninsula and other regions within the Western United States with complex terrain. The complete downscaling system was delivered to Forest Service users and training was provided.

Contact: Ron Neilson,, Ecological Process and Function Program

Partner: Oregon State University


Old growth in a new world

Book Old Growth in a New World

Old-growth forests have been an icon of the Pacific Northwest for more than 100 years. Despite their prominence in ecological science and policy debates, few studies have examined them in terms of a linked social-ecological system. The book Old Growth in a New World: A Pacific Northwest Icon Reexamined, published in 2009 by Island Press, examines the old-growth issue from the perspective of ecologists, social scientists, and stakeholders. The history of old growth in the Pacific Northwest is a history of social change. The science of old growth is maturing to incorporate ecosystem dynamics and complexity and the recognition that conservation of old growth sometimes means undertaking active management to achieve ecological goals. The collection of essays, and the conference from which they arose, have elevated the discussion of old-growth forests, leading to a productive discourse among a wide range of people and the groups they represent.

Contact: Thomas A. Spies,, Ecological Process and Function Program

Partners: National Commission on Science for Sustainable Forestry, Oregon



Branch architecture and wood density determine leaf functional traits in tropical trees

Rates of photosynthesis, transpiration, and efficiency of water movement through leaves differ by tree species. These functional traits provide valuable information about how a species might respond to different environmental conditions, and when examined collectively, how the entire ecosystem may respond. In tropical forests, however, the sheer number of different tree species presents daunting challenges for interpreting and predicting the functional traits of the forest canopy based on a small subset of species.

Therefore, researchers looked for common denominators that would be relatively easy to measure, yet would still provide the needed information. Working along a rainfall gradient across the Isthmus of Panama, researchers found that wood density and simple architectural features such as leaf area to sapwood area ratio accounted for a large fraction of the variation in leaf and stem functional traits among tree species. This information will help tree physiologists, plant ecologists, and vegetation modelers who are interested in developing common rules to better describe the behavior of trees and complex, multispecies ecosystems under a variety of environmental conditions.

Contact: Rick Meinzer,, Ecological Process and Function Program

Partners: North Carolina State University; Universidad de Buenos Aires, Argentina; University of Miami


Trees rely on two principal mechanisms for avoiding hydraulic failure

As water is pulled from the roots to the leaves under negative pressure, or tension, air bubbles known as emboli may enter and block the water-conducting xylem tissue. Previous studies on the ways in which plants avoid embolism have focused primarily on the role of xylem structure in avoiding catastrophic hydraulic failure. A new analysis of more than 100 woody species suggests that there is actually a continuum of relative reliance on two main mechanisms that confer hydraulic safety. Species with low water storage capacity and denser wood experience greater daily maximum xylem tension and appear to rely primarily on xylem structural features to avoid embolism. Species with high water storage capacity and low wood density appear to avoid embolism by relying on transient release of stored water to constrain transpirationinduced fluctuations in xylem tension.

The findings are fundamental to understanding how trees maintain safety margins in the face of environmental stress. Findings will result in more realistic modeling of tree species distribution and performance under different climate regimes.

Contact: Rick Meinzer,, Ecological Process and Function Program

Partner: Oregon State University


Leaves are the first line of hydraulic defense in conifers and other woody species

microscope of hydrated Douglas-Fir needleThe hydraulic efficiency of leaves decreases as drought stress increases, eventually resulting in reduced photosynthesis. By using various techniques, including detection of ultrasonic acoustic emissions and imaging of dehydrated leaves flash-frozen in liquid nitrogen, researchers determined that water-stress-induced loss of leaf hydraulic efficiency in two pine species and two shrubs was directly related to emboli—or air bubbles—in the leaf xylem. They also found that emboli formed daily in field-grown plants and that the process was reversed in the afternoon and overnight. Rapidly reversible embolism in leaves may constitute part of an essential hydraulic signal that triggers stomatal closure, ensuring the integrity of water transport in the stems upstream from the leaves.

The findings provide insights into the mechanisms by which plants respond to and cope with environmental stresses such as drought.

Contact: Daniel Johnson,, or Rick Meinzer,, Ecological Process and Function Program

Partner: Oregon State University


Montane red foxes are ecologically and evolutionarily distinct

Montaine Red FoxBased on analyses of ecological, historical, archeological, fossil, and other data, scientists hypothesized that populations of red fox that occupy highelevation boreal forests in the Cascade Range, Sierra Nevada, and Rocky Mountains were derived from populations that were isolated south of the ice margin during the last glaciation, and that they are ecologically and evolutionarily distinct from red foxes living elsewhere. The scientists used genetic analyses to test this hypothesis. They found that the montane red foxes were derived from populations that had colonized North America from Asia during the penultimate glaciation and became isolated in ice-free refugia in the contiguous United States during the last glaciation. These results indicate that the montane red foxes are specialized to subalpine and alpine habitat conditions and do not cross intervening habitat areas. Given their long-term isolation and the extreme climatic conditions they occupy, montane red foxes may possess physiological adaptations that other populations lack. These findings support treating the montane red foxes as evolutionarily distinct. In California, the Sierra Nevada red fox is a state-listed threatened species, and their decline in the Sierra Nevada has been documented over several decades. The status of montane red fox populations in the Cascade Range and Rocky Mountains is unknown, but given the likely impacts of climate change on suitable habitat, this study may provide information for their future conservation.

Contact: Keith B. Aubry,, Ecological Process and Function Program

Partners: California Polytechnic State University, Kansas State University, University of California at Davis


Population density of North American elk significantly influences vegetation diversity

elk herdLarge herbivores, such as elk and deer, are common across western North America. Their impacts generally have been ignored in most management documents because their effects vary across landscapes. However, what herbivores eat and the resulting changes this brings to the diversity in understory plant species and plant productivity may have cascading effects on other organisms, overall biodiversity, and on forest productivity.

In a study conducted on the Starkey Experimental Forest in eastern Oregon, scientists observed significant indirect relationships between the number of herbivores in an area and plant productivity and plant diversity. Those subtle effects of herbivory may have strong effects on ecosystem functioning, even in plant communities that are relatively resilient to herbivory. This information may help land managers develop sustainable management practices for forest and range land including stocking levels of herbivores.

Contact: Brian Dick,, Ecological Process and Function Program

Partners: Idaho State University, University of Nevada, Reno


Marbled murrelet populations are declining in the Northwest Forest Plan area

marbled murreletThe marbled murrelet, a seabird, is a threatened species under the Endangered Species Act. The 1996 Northwest Forest Plan is the guiding plan for managing the bird's terrestrial habitat that runs along the coast of Washington, Oregon, and northern California. To determine if the plan is working, researchers have monitored murrelet population since 2000. By using at-sea transects in coastal waters adjacent to the plan area, scientists have estimated the size of the murrelet population, and it appears that from 2000 to 2009, murrelets have declined by 2 to 4 percent per year, depending on how the data are analyzed. Habitat losses have been minimal on federally managed lands; however, losses on private lands, and nest predation associated with urban encroachment have increased and may be responsible for some of the decline in population.

The U.S. Fish and Wildlife Service used this information in their status assessment of the marbled murrelet. Based in part on these results, the service determined that the species should continue to be listed as threatened. Resource managers are using these findings to evaluate the role of forest
conditions in contributing to the observed decline.

Contact: Martin G. Raphael,, Ecological Process and Function Program

Partners: USDA Forest Service, National Forest System, USDI Bureau of Land Management and
Fish and Wildlife Service; Washington Department of Fish and Wildlife


Nightlife of red tree voles caught on camera

red tree volesRed tree voles live high in the tops of coniferous trees in western Oregon and northwestern California. They are an important food for the threatened northern spotted owl, and there is concern that they may be declining as old forests are removed and replaced by intensively managed young forests. This has led to extensive attempts to survey them by searching for nests from the ground and then climbing trees to confirm that the nests were built by tree voles. But because the voles are nocturnal and so far from the ground, not much was known about their basic habits. To learn more, researchers used radio transmitters and video cameras to document the movements and behavior of red tree voles, from 2002 to 2007. These studies are the first to describe the movements and foraging behavior of tree voles at night, when they are active in the forest canopy.

Researchers found that 62 percent of the observed voles occupied home ranges that included multiple nests in different trees, and that voles sometimes came to the ground to move between nests if there were no interconnecting limb pathways between trees. Researchers also found that many tree vole nests could not be detected by ground-based visual surveys, especially in old forests, where nests were often located inside cavities in the broken tops of large trees. These findings will help land managers and ecologists design management plans for red tree voles and improve survey methods for tree voles.

Contact: Eric Forsman, eforsman, Ecological Process and Function Program

Partners: Oregon State University, USDI Bureau of Land Management


Habitat networks foster efficient broad-scale conservation planning

cheatgrass fieldOne management challenge for wildlife species of conservation concern is determining how the requirements of multiple species can be reduced to a workable number and yet sufficiently represent the ecological needs of the comprehensive set of species. Habitat networks offer one promising approach.

Scientists developed a habitat network for five groups of terrestrial vertebrates in the interior Columbia basin and a similar network for sagebrush-associated vertebrates in the Great Basin. This process revealed spatial patterns of habitat abundance, quality, and threats to habitat from invasive species. Watersheds in which all or most habitat had been lost were widely distributed across the ranges of old forest and sagebrush-associated species of the interior Columbia basin, indicating substantial declines in amount, quality, and resiliency of habitats. In the Great Basin, watersheds with abundant habitat at low risk were rare for key species groups.

This study demonstrated that mapping habitat networks can foster efficient conservation planning at regional levels by identifying areas where efforts to protect or restore habitat will be most effective. This process can be augmented with spatial models that incorporate characteristics such as population connectivity and land protection status.

Contact: Mary Rowland, Ecological Process and Function Program

Partners: USDA Forest Service National Wildlife Ecology Program, USDI Bureau of Land Management, USGS Biological Resources Discipline



Framework for Predicting Postfire Forest Change in Interior Alaska

black spruceDescription: This set of tools provides forest managers with a rule-based framework for predicting what type of forest will regenerate after fire in interior Alaska. The forests of interior Alaska are currently dominated by black spruce, and standreplacing wildfires are the main form of disturbance. The fire regime in the region is changing, however, and further changes are expected with climate warming. These changes may lead to more deciduous tree cover in areas previously dominated by black spruce. These forest types differ dramatically in their potential fire behavior and provision of wildlife habitat and other forest resources. Postfire successional trajectories in black spruce forests of interior Alaska can be predicted based on prefire species composition, fire severity, and site moisture.

The framework includes four tools: (1) a key to classifying potential site moisture, (2) a summary of conditions that favor black spruce self-replacement, (3) a key to predicting postfire forest recovery in recently burned stands, and (4) a set of photos that serve as a visual reference tool. Use: Managers from the Alaska Fire Service, Alaska Division of Forestry, U.S. Fish and Wildlife Service, and National Park Service are using these tools to help design fire management actions and to predict the effects of recent and future fires on postfire forest cover.

Contact: Teresa Hollingsworth,, Ecological Process and Function Program

Partners: University of Alaska Fairbanks; University of Saskatchewan Saskatoon

For more information: Johnstone, J.F.; Hollingsworth, T.N.; Chapin, F.S., III. 2008. A key for predicting postfire successional trajectories in black spruce stands of interior Alaska. Gen. Tech. Rep. PNW-GTR-767. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 37 p.



New metric for measuring the fuel available for crown fires

Middlefork CreekDescription: Crown bulk density (CBD), the metric commonly used to quantify canopy fuel available for combustion in the event of a crown fire, is difficult to consistently measure. It is a three-dimensional metric based on the mass of foliage, twigs, and an approximation of canopy volume of a stand of trees. Scientists developed an alternative, onedimensional metric that only uses the amount of foliar biomass per unit area in a stand. This metric is a novel solution because foliar biomass can be reliably estimated and is easily related to stand conditions including leaf area index, basal area, and transpiration. This new metric was found to be statistically equivalent to CBD when comparing the modeled minimum rate of spread necessary for active crown fire across a broad range of stand conditions. The new metric is the first potential alternative to the existing CBD metric since its introduction in 1977.

Use: State and federal wildland fire and fuel treatment planners now have a more easily obtainable, consistent metric for assessing crown fire potential.

Contact: James D. Dickinson,, Ecological Process and Function Program


Customized models based on BlueSky modeling framework

Description: Users can now create custom consumption, emissions, and smoke dispersion model runs based on their specific model choices by using the new BlueSky Web-service functionality similar to that found in other online tools. This means users do not need to install any additional software. This new feature has led to the addition of new models, increasing the capabilities for the BlueSky framework, and to research studies aimed at using BlueSky's functionality to understand model-tomodel variations, which can help focus model development.

Use: Through the National Fire Consortia for Advanced Modeling of Meteorology and Smoke partnership, air quality managers, land managers, and fire managers now have access to a national smoke prediction system that creates tailored smoke model predictions. Custom smoke model predictions are also helping managers at the Northwest Coordination Center understand model prediction uncertainties through an ensemble of daily customized smoke prediction runs that are produced.

How to get it: To view current model predictions go to //; to learn about BlueSky's capabilities go to //

Contact: Narasimhan Larkin,, Ecological Process and Function Program


New deer model for the Tongass National Forest

Description: The values for this new model are derived from field data analyzed with the station's Forage Resource Evaluation System for Habitat–Deer (FRESH-Deer), which is entirely transparent in its theory and calculations and is based on strong biological science. The model replaces a controversial expert-opinion model that led to legal challenges because of its hidden assumptions and relative lack of data-based analysis.

The new Tongass model also includes a process for immediately incorporating new results from the young-growth silviculture adaptive management program Tongass-Wide Young-Growth Studies (TWYGS). The TWYGS results are original field data, statistically strong, and updated annually. The combination of FRESH-Deer and TWYGS provides the Tongass National Forest with an always current tool for quantitatively evaluating habitat and potential forest management alternatives. Use: The Tongass National Forest is using this model in routine land management planning and analysis. It is expected to greatly reduce contention around deer habitat analysis and related legal appeals to Tongass National Forest management decisions.

How to get it: The FRESH-Deer habitat evaluation system is available at // The new Tongass National Forest deer model is available through Jim Brainard (jbrainard@fs.fed. us) or Patricia O'Connor ( of the Tongass National Forest.

Contact: Thomas A. Hanley,, Ecological Process and Function Program


US Forest Service - Pacific Northwest Research Station
Last Modified: Tuesday,13December2016 at09:17:12CST

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.