Highlights from the Andrews Forest Program are listed below. Also see "LTER Transformative Science" for a list of important contributions to ecological science from the Andrews Forest program, compiled at the request of the National Science Foundation.
Carbon stored reflects timber harvest history
The amount of carbon stored in tree trunks, branches, leaves and other biomass — what scientists call “aboveground live carbon” — is determined more by timber harvesting than by any other environmental factor in the forests of the Pacific Northwest, according to a report published by researchers at Oregon State University (doi:10.1016/j.foreco.2016.01.036).
In forests that are about 150 years old or less, live carbon above the ground is associated primarily with the age of a stand — reflecting how long ago it was harvested — rather than with climate, soil, topography or fire. However, as forests mature into “old growth,” the density of carbon is determined largely by factors other than harvesting.
The Pacific Northwest has some of the highest forest-carbon densities in the world. Understanding how much carbon is stored in growing forests is a critical component of international efforts to reduce climate change.
Researchers found that air temperatures, sun exposure and soils were also important in driving the variation in live carbon across the region. High-elevation forests tend to be cooler and contain lower amounts of carbon than do low-elevation forests.
Researchers conducted the study at the H.J. Andrews Experimental Forest in the Cascade Range east of Eugene. They combined data from two types of measurements: LiDAR (an aerial mapping technique that uses lasers) and ground-based forest inventories in which scientists measured tree growth at 702 forest plots. The study is one of the few to quantify carbon in living forest biomass in mountainous terrain.
Harold Zald, research associate in the College of Forestry, is lead author of the paper published in the journal Forest Ecology and Management.
“Very few studies have looked at above-ground carbon at a landscape scale with the combination of LiDAR and detailed disturbance history (logging and fire) that we have at the H.J. Andrews Forest,” said Zald. “These findings can be applied to the Douglas-fir dominated forests on the west slope of the Cascades in Oregon and Washington.”
The researchers found that fire was not a significant driver of carbon density in the H.J. Andrews. In the last century, these forests have experienced little severe “stand replacing fire,” but it’s possible that fire played a significant role in shaping the structure of old-growth forests and increasing carbon density over time. “Remnant old-growth trees resulting from non-stand replacing fires likely enhance the recovery of forest C (carbon) density,” they wrote.
The study was conducted by researchers at Oregon State University, the Pacific Northwest Research Station of the U.S. Forest Service and the University of Natural Resources and Life Sciences (BOKU) in Vienna, Austria.
Media contact: Nick Houtman, 541-737-0783, email@example.com
Sources: Harold Zald, 541-737-8719, firstname.lastname@example.org
This story is also available at http://bit.ly/1U7tKrT.
Old-growth forests may provide buffer against rising temperatures
New research from the Andrews Forest suggests that old-growth forests may provide a buffer against rising air temperature. Press release: http://bit.ly/1U7sBkd
Rot: The Afterlife of Trees. Forest Ecology Research Interpreted Through the Arts
Mark Harmon and other scientists at OSU have invited artists to use the idea of dead wood as a starting point for the creation of various kinds of visual and musical arts. An exhibit – “Rot: The Art of Dead Wood or The Afterlife of Trees” – was unveiled on January 14, 2016, at the Corvallis Art Center. The exhibit featured a number of events including a public reception, artist brown-bag discussion, art walk, and sessions featuring readings and music inspired by this underappreciated ecological process. The exhibit moved to the World Forestry Center in Portland, Oregon, from March 11 - May 1, 2016. Harmon hopes the exhibit will bring an increased awareness of the value of dead trees to the public. See the "Rot: The Afterlife of Trees at The Arts Center" article in the Corvallis Gazette Times.
Andrews Forest inspired artwork on exhibit
The Long-Term Ecological Reflections program of the H.J. Andrews Experimental Forest is the subject of a growing body of arts and humanities works closely linked with the long-term ecological research program based in the forest. This work is in part the result of a collaboration among the Spring Creek Project, the Andrews Forest science community, the US Forest Service Pacific Northwest Research Station, and the National Science Foundation, which has helped fund both the Long-Term Ecological Research and humanities programs at the Andrews Forest.
Artist Bob Keefer recently showed about 50 of his painted photographs in an exhibit called “Forest Investigations” at the Jacobs Gallery in Eugene; these works are based on a rainy Andrews Forest residency. And now several of Leah Wilson’s paintings in her “Ambient” series are displayed in the lobby of the Greenhouse—check them out and note the caption describing her science-like rigor in creating her art. Upcoming is the exibit, "Rot: The Afterlife of Trees," a multi-media exhibition that will be shown at The Arts Center in Corvallis in January 2016 (http://theartscenter.net/rot-the-afterlife-of-trees-blog/), and at Portland's World Forestry center in February.
Using Maps to Study Birds
A publication co-authored by a team of Oregon State University, US Forest Service, and US Geological Survey investigators compares quality of interpretation of northern spotted owl habitat based on traditional aerial photographs, Landsat satellite imagery, and recently-available, high-resolution LiDAR data. This team, led by Steve Ackers, head of the Andrews Forest-based spotted owl crew, uses the well-studied Blue River-Andrews Forest area as a test case. Information from these data sources is used in sophisticated species distribution models for the spotted owl, and many other species as well. As one might expect, each information source has its pluses and minuses. Air photo interpretation is rather subjective, hard to reproduce, and time consuming. Landsat has proven an adequate tool for extensive assessment of habitat quality, although it lacks the high precision possible with LiDAR. It is interesting to note that the first Landsat Thematic Mapper satellite was launched in 1972, just as Eric Forsman began studies of the spotted owl in the Andrews Forest and vicinity, and the first report using that imagery in habitat assessment appeared just two years later. The meter-scale LiDAR data describing topography and vegetation structure makes possible a very refined depiction of habitat, but LiDAR data are not available for the whole region, and the high precision is not necessary for many conservation purposes. See the paper: The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps.
A Century of Forest Change
In ecological research, it’s rare to have a century-long record. But the Andrews Forest team has just that from three plots, established in April 1910 in the Willamette National Forest, by pioneer Pacific Northwest forester, T.T. Munger (see Fall 2010 Andrews Forest newsletter). Mark Harmon and Rob Pabst published a new paper analyzing records of tree establishment, growth, and death observed at 5–10 year intervals as the stands aged from 54 to 154 years. Predictions about population, community, and ecosystem change over this time period have been primarily based on “chronosequence” studies—trading space for time—by examining variation among stands of different ages but in similar environments. Comparing these predictions with plot records, Mark and Rob find the predictions hold up for change over time of plant populations (e.g., Douglas-fir stem density decreases over time) and community structure (e.g., shade-intolerant Douglas-fir gives way to shade-tolerant tree species), but surprisingly, at the ecosystem level, live stand biomass constantly increased over the century of record—much longer than predicted from ecosystem theory, which suggests that increasing mortality would slow the rate of biomass accumulation. Andrews Forest ecologists are tracking 79 additional old plots (75–100 years old) on five other national forests in the region, which will yield tests of these findings. See the full article, Testing predictions of forest succession using long-term measurements: 100 yrs of observations in the Oregon Cascades
The Andrews Forest program and OSU Extension are collaborating in a Citizen Science project on climate and ecology. The project, Season Trackers, enlists citizen scientists to make weather and phenology observations in their communities around the state by recruiting from the ranks of people already involved with Extension’s many programs statewide, including many in rural areas. The data will help Andrews scientists expand the scale and inference of their research activities beyond the boundaries of the HJ Andrews Experimental Forest. Learn more about the program through the Oregon Season Tracker website. The website has information about how to become involved, upcoming trainings, and resources to help volunteers with observations.
Monitoring birds across the landscape with new tools
Andrews Forest scientists recently recieved a grant from the National Science Foundation to develop computer software that will identify birds by song, a tool that will allow researchers to more easily monitor birds across a landscape. Raviv Raich and Xiaoli Fern (OSU Electrical Engineering and Computer Science) and avian ecologist Matthew Betts (OSU Forest Ecosystems and Society) lead the project titled “Computational Methods for Bioacoustic Avian Species Monitoring”. The main thrust of the project is further development of machine learning techniques for automated interpretation of recordings of bird song to identify species and their movement across the landscape during the summer season. Several years of recordings of bird songs at many locations across the Andrews Forest landscape (currently >12 TB of data) will be used to test the techniques and address ecological questions relating to phenological shifts in bird arrival in relation to food availability. The tool will be adaptable to many ecosystems, but will be tested first by addressing bird response to environmental change, including climate variability in the Andrews Forest and land use in Costa Rica. See http://www.forestry.oregonstate.edu/bioacoustics-birdland and http://oregonstate.edu/terra/2010/07/birding-by-ear-online/ for more detail.