Posts Tagged: forests
Do Forests Play a Role in Bumble Bee Life History?
Do forests play a role in bumble bee life history? Yes, says UC Davis alumnus and research...
The cover image of BioScience by Diego Delso shows a Bombus terrestris, a buff-tailed bumble bee that is one of the most numerous bumble bee species in Europe.
New project to build climate resilience through improved land management
A $4.6 million grant to UC Merced and UC Irvine will help UC Agriculture and Natural Resources researchers develop new tools and methods for California land owners to better manage the state's forests, shrub lands and grasslands.
California's Strategic Growth Council agreed to fund the Innovation Center for Advancing Ecosystem Climate Solutions, a three-year program co-led by UC Merced Professor Roger Bales and UC Irvine Professor Michael Goulden. The money comes through California Climate Investments, a statewide initiative that puts billions of cap-and-trade dollars to work
The goals include reducing wildfire risk, improving long-term carbon sequestration and bolstering resilience in the face of climate change, with an emphasis on California's rural regions and low-income communities.
“Our part of the project is to work with stakeholders and identify areas where we can focus management practices to promote healthy forests, minimize wildfires, improve water security and increase carbon sequestration,” said Toby O'Geen, UC Cooperative Extension soil resource specialist at UC Davis.
“Right now, many of California's forests, shrub lands and grasslands are carbon sources, and we need to change them into carbon sinks,” said Bales, director of the Sierra Nevada Research Institute and distinguished professor of engineering. “Our research will address information bottlenecks to guide decision making, build local capacity for science-based land management and develop methods for translating benefits of land restoration into financing for land restoration.”
California's recent drought, tree die-offs, wildfires and rising temperatures all point to the necessity of improved forest stewardship, Goulden said.
“Officials in the state government and agencies recognize this need, but uncertainty over how to proceed has sometimes slowed progress,” he said.
Most of the work will be conducted by scientists at Merced and Irvine, but collaborators from UC Berkeley, UC Davis, Stanford University, San Diego State University and the University of California Division of Agricultural and Natural Resources, as well as state agencies, will play important roles.
“This research will enable UC Cooperative Extension advisors to provide better advice to land managers to reduce the severity of wildfires,” said Glenda Humiston, UC vice president for agriculture and natural resources. “Severe wildfires are not only releasing greenhouse gases, but polluting the air of many communities, aggravating the health of people in less-affluent, inland areas such as Tulare, Yuba and Mariposa counties.”
At UC Merced, an interdisciplinary group of researchers from two departments — Civil & Environmental Engineering and Management of Complex Systems — will collaborate with UC Cooperative Extension and engage with local stakeholders. The group will study and identify the most-effective land-management practices, in terms of water conservation, forest health, fire resistance and carbon capture.
“We will develop the spatial data and analysis tools to plan landscape restoration, develop local capacity for better managing the state's wildlands in a warming climate, and enumerate the greenhouse gas and other benefits from investments in land management,” Bales said.
Goulden, professor of Earth systems science, said UC Irvine researchers will use a big-data approach to analyze observations collected by satellites since the 1980s to measure the efficacy of thousands of past and ongoing forest treatments, while UC Merced takes a different approach.
“We will work with groups in rural communities to systematically evaluate how well, or poorly, our products can support decision making,” Bales said, “and then develop both implementation pathways and policy recommendations to better and more-quickly implement landscape-restoration and carbon-capture projects across the state.”
Because there are critical gaps in the understanding of carbon cycles, uptake by forests and negative feedback from climate change, this project initiative has been established to develop new knowledge through measurements and modeling. Researchers will synthesize the resulting data to produce actionable information for stakeholders.
Bales and Goulden agreed the Innovation Center will target low-risk, high-yield opportunities to reduce California's greenhouse-gas contributions.
Just a small improvement in management efficiency will have meaningful benefits — on the order of several million metric tons of CO2 per year, Goulden said.
The program will also benefit low-income communities in the state by reducing wildfire risk, which disproportionately impacts poorer areas in California; by maintaining water quantity through better vegetation management; by fostering tourism in disadvantaged locales; and by preparing students in these areas for careers in sustainability and climate resilience.
Decreasing forest density will reduce fire risk, build climate resilience
California needs to increase the pace and scale of efforts to improve the health of its headwater forests — the source of two-thirds of the state's surface water supply. Management techniques including prescribed fire, managed wildfire and mechanical thinning can help rebuild resilience in these forests and prepare them for a challenging future.
These are among the key findings of a report released today by the PPIC Water Policy Center.
Decades of fire suppression have increased the density of trees and other fuels in headwater forests to uncharacteristically high levels and resulted in massive tree die-offs and large, severe wildfires. Improving forest health will require reducing the density of small trees and fuels on a massive scale.
This will require changes in the regulation, administration, and management of forests. Many of the recommended reforms in forest management can take place at low or no cost. But implementing them will require vision, determined leadership by state and federal officials, and the backing of an informed public.
“Actions to arrest the decline in forest health will take place far from urban centers,” said Van Butsic, a coauthor of the report and a UC Cooperative Extension specialist in the Department of Environmental Science, Policy and Management at UC Berkeley. “But all Californians will benefit through continued supplies of high-quality water, natural environments, forest products and recreational landscapes.”
Changing the way forestry work is funded — and in some cases securing new funding — will also be needed to help expedite forest improvements. The authors suggest reforms that will enable the private sector and government agencies to use existing tools and funding opportunities more effectively and collaborate more easily on larger-scale management projects. One key recommendation is to find opportunities to combine revenue-generating timber harvesting with other management work to help offset the costs of efforts to improve forest health.
“Making forest health a top land management priority for public and private lands would be a critical first step in reversing the degraded condition of the state's headwater forests,” said report coauthor Henry McCann, a research associate with the PPIC Water Policy Center.
The report, Improving the Health of California's Headwater Forests, was supported with funding from the S. D. Bechtel, Jr. Foundation and the US Environmental Protection Agency. In addition to Butsic and McCann, the coauthors are Jeffrey Mount and Brian Gray, both senior fellows at the PPIC Water Policy Center; Jodi Axelson, a UC Cooperative Extension specialist at UC Berkeley; Yufang Jin, an assistant professor in the Department of Land, Air, and Water Resources at UC Davis; Scott Stephens, professor of fire science and co-director of the Center for Forestry and Center for Fire Research and Outreach at UC Berkeley; and William Stewart, a UC Cooperative Extension specialist and co-director of the Center for Forestry and Center for Fire Research and Outreach at the UC Berkeley.
Recycling Christmas trees helps curb the spread of pests
If you have a real Christmas tree, University of California pest management experts ask that you to recycle the tree to prevent the spread of insects and diseases that may harm our forests and landscape trees.“Invasive insects, diseases and plant seeds can move on cut Christmas trees and other holiday greenery,” said Janice Alexander, UC Cooperative Extension forest health educator in Marin County. “These pests can escape out into backyards and neighboring forests to begin new populations, upsetting the balance of our native ecosystems. Proper purchasing and disposal of holiday greenery helps reduce that risk.”
Alexander recommends taking advantage of local tree recycling programs.
“Many municipalities and service organizations offer this service right at your curb,” she said. “If you aren't able to find or use this option, take the tree to your local solid waste facility, dump or landfill. This will keep any pests that might be in the tree from spreading and the landfill uses the material as cover.”“You should not try to burn the wood indoors as fresh sap can create fire hazards,” she added, “and don't set the tree out in a backyard brush pile where pests and weed seeds could escape onto your property.”
“The most worrisome pests that might be traveling on Christmas trees or greenery this year include P. ramorum, pine shoot beetle and gypsy moth,” Alexander said.
The movement of some fresh trees is regulated. For example, Douglas fir trees are regulated because they are hosts for Phytophthora ramorum, which causes sudden oak death. The disease has killed millions of tanoak trees and several oak tree species in forests throughout California since the mid-1990s.
Pine shoot beetle and gypsy moth are not currently in California, but they could damage the state's Christmas tree plantations and forests if they were to become established.Pine shoot beetles, Tomicus piniperda, feed on shoots, stunting the growth of pine trees. Large populations of the insects can kill apparently healthy trees.
Gypsy moth, Lymantria dispar, attacks forests and landscape trees, including manzanita, western hemlock, Douglas fir and live oak. Gypsy moth caterpillars feed on hundreds of plant species and are capable of defoliating trees at an alarming rate. A single gypsy moth caterpillar can eat up to one square foot of leaves per day, according to the California Department of Food and Agriculture.
“According to the Don't Move Firewood website, Christmas trees are generally deemed safer than firewood in terms of invasive pests,” Alexander said. “However, safe disposal of trees is still important.”For more information about sudden oak death and forest health, visit Alexander's website at http://cemarin.ucanr.edu/Programs/Custom_Program816. More information about holiday greenery pests can be found at the USDA APHIS website and the Don't Move Firewood website http://www.dontmovefirewood.org/HolidayGreenery.
Got calcium? Mineral key to restoring forests
Calcium can do much more than strengthen bones. The mineral is a critical nutrient for healthy tree growth, and new research shows that adding it to the soil helps reverse the decades-long decline of forests ailing from the effects of acid rain.
“It is generally accepted that acid rain harms trees, but the value of our study is that it proves the causal link between the chronic loss of soil calcium caused by decades of acid rain and its impact on tree growth,” said Battles. “The temporal and spatial scope of the study – 15 years and entire watersheds – is unique and makes the results convincing.”
The researchers reported that trees in the calcium-treated watershed produced 21 percent more wood and 11 percent more leaves than their counterparts in an adjacent control site. The iconic sugar maple – the source of maple syrup – was the tree species that responded most strongly to the restoration of calcium in the soil.
Acid deposition has altered the calcium cycle in watersheds in the Northeastern United States in ways that are similar to changes observed at Hubbard Brook Experimental Forest.
The research site, managed by the U.S. Forest Service, was targeted because of the declining growth rates and unexpected death of trees in the area. Previous measurements of the forest soil showed a 50 percent depletion of calcium.
Acid rain forms when sulfur dioxide and nitrogen oxides – gases produced from the burning of fossil fuels – react with water molecules in the air. The mountainous regions in the Northeast have thin soils that are already acidic, so they have limited ability to withstand the assaults of nutrient-dissolving acid rain. Moreover, watersheds along the eastern corridor of the United States had been exposed to more acid rain because of the greater number of coal-burning power plants in the region.
The Clean Air Act of 1970 significantly reduced sulfur dioxide emissions, but decades of acid rain already had changed the soil chemistry of many sensitive regions, including the White Mountains of New Hampshire and the Adirondacks of New York.For the Hubbard Brook study, a helicopter spread 40 tons of dry calcium pellets over a 29-acre watershed over several days in October 1999. The calcium was designed to slowly work its way into the watershed over many years.
“This was restoration, not fertilization,” said Battles. “We were only replacing what was lost.”
Researchers monitored the forest over the next 15 years, comparing the treatment area with an adjacent watershed that had the same characteristics, but did not get the added calcium.
“The treatment increased the forest’s resilience to major disturbances,” said Battles. “The trees in the calcium-treated watershed were able to recover faster from a severe ice storm that hit the region in 1998.”
“This study has important implications that go well beyond the forests of the northeastern United States,” said Dave Schindler, a professor of ecology at the University of Alberta in Canada who was not part of this research. “Similar depletion of soil nutrients by acid precipitation has occurred in much of eastern Canada and Europe. This long-term study indicates that the calcium problem can be reversed, and that is heartening.”
Both Schindler and Battles noted that the high cost of adding calcium to the soil would likely limit its use to targeted watersheds rather than as a treatment for vast areas of affected forests.
“Prevention is always preferable, and with our study’s clear evidence that acid rain is hurting forests, other countries will hopefully be motivated to intervene sooner by implementing air pollution standards to reduce emissions,” said Battles.
Funding from the National Science Foundation helped support this research.
RELATED INFORMATION
- Acid Rain Revisited (Hubbard Brook Research Foundation)
- Effects of Acid Rain – Forests (U.S. Environmental Protection Agency site)