How Will Climate Change Impact the Composition of Microbial Communities in Coastal Redwood Forest Soils?on
When you look up from the bases of a giant coast redwoods, they seem indestructible. After all, some coast redwoods living today were alive during the time of the Roman Empire.
But coast redwoods need healthy soil and its tiny organisms to survive. So how will climate change affect the forests’ fungi and bacteria? A research team led by Professor Mary Firestone at the University of California, Berkeley, recently found a way to mimic what the future may hold.
Aided by a grant from Save the Redwoods League made possible with support from you, our members, the team took samples of soil from three locations in the north, south and central regions of coast redwoods’ range: from Prairie Creek Redwoods State Park, Big Basin Redwoods State Park and the Grove of Old Trees in Sonoma County. At each of these sites, soil samples from the other locations were installed and analyzed twice, after one and three years.
In some ways the sites are similar: They are all flat and have old-growth redwoods towering over an understory of sword fern, tan oak and sorrel. But the sites’ soils include different combinations of microorganisms nurtured in different climates. At Prairie Creek, there’s more precipitation and lower temperatures; at Big Basin, less precipitation and higher temperatures.
In the beginning, Firestone wasn’t sure whether transplanted soils would remain the same, become more like the native soils, or take off in some unpredictable direction. After three years, “the organisms became more like the community indigenous to the location we moved them to,” she said. “But the speed of the response was slow.” Of more than 2,300 bacteria species detected, 3.2 percent changed their abundance within one year of the transplant, and 12.4 percent after three years.
The researchers noted other changes as well. “Transplanted nitrifiers (soil bacteria) were knocked back at one year,” Firestone said, “but started to rebound in three years.” Fungi, which form vital symbiotic associations with redwoods, tended to make the transition more easily.
On balance, the results are good news for redwood soils in a changing climate. “The response to the change was slower than many people would have expected,” Firestone said. “But we didn’t see any really negative consequences on the communities or their functioning.”
You can help us learn more lessons like these to understand how to best protect redwoods and what the forest’s long-term survival means to the health of people and our planet. Please donate today.
Explore More Research Grants
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Redwood Forest Restoration and Martens
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Promoting Giant Sequoia Regeneration
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Small Giant Sequoia Groves May Not Endure
More than 30 years ago, giant sequoia seeds were collected in 23 groves representing the species’ range from north to south in the Sierra Nevada. They were propagated and planted on US Forest Service land 20 miles east of Auburn, California, that was hotter, drier, lower in elevation and farther north than any of their original homes. This experiment, the legacy of William J. Libby, UC Berkeley emeritus professor and Save the Redwoods League board member, has been studied and carefully maintained ever since. Learn more about this research.
Deciduous Ferns May Hold Advantage as Climate Changes
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Redwood Forest Edges Offer Habitat for Evolution
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Snail Invasion Could Mean Trouble for Food Web
Humboldt State University fisheries biologist Darren Ward was concerned, but not surprised, when New Zealand mud snails showed up in Redwood National Park in 2009. With help from a grant from Save the Redwoods League, Ward and a colleague at the US Geological Survey, Adam Sepulveda, began searching to see if they were moving upstream. Learn more about this research.
Redwoods Regrow After Fires
In the past 70 to 80 years, most fires in California’s coast redwood forests were prevented or suppressed. But in 2008, more than 2,000 fires ignited forests in Northern and Central California during a single summertime lightning storm. Overwhelmed by conflagrations in drier areas, firefighters allowed many of fires in coast redwood forests to burn. Learn more about this research.
Redwood Forests May Be Crucial for Silver-Haired Bats
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Disturbances Benefit Giant Sequoias
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Tanoak Decline in Redwood Forests
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Black Salamanders Show Biodiversity of Redwood Forest
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Forest Restoration through Thinning
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Redwood Soil Microbes Can Adapt to Climate
Coast redwoods need healthy soil and its tiny organisms to survive. So how will climate change affect the forests’ fungi and bacteria? A research team led by Professor Mary Firestone at the University of California, Berkeley, recently found a way to mimic what the future may hold. Learn more about this research.
Central California Redwoods More Vulnerable
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Pre-Logged Northern Redwood Forests
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Fog and Redwood Forest Plants
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Examining Coast Redwood Genes
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Coast Redwoods’ Response to Disturbance Events
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Thinning Would Spur Old-Growth Qualities
Upland forests in Redwood National Park have been studied extensively. But until a few years ago, less was known about streamside, or “riparian,” forests, which benefit the park’s salmon habitat by providing shade, erosion control and woody debris in the streams. So Humboldt State University graduate student Emily King Teraoka decided to compare two of the park’s riparian forests: one along Lost Man Creek, which had been clearcut between 1954 and 1962; and one along Little Lost Man Creek, which was mostly untouched. Learn more about this research.
Amphibian Populations Predict Forest Health
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Growing New Giants Through Canopy Gaps
It seems unfathomable that the tiny seedlings Rob York sowed among ash piles in a clearing at Whitaker’s Forest could someday grow to be among the largest creatures on earth. Yet these green specks grew into giant sequoias two years after seeds were strewn in canopy gaps. This species of titan tree has stagnated in regeneration efforts for nearly a century. York, along with his graduate advisor, John Battles, is working on unlocking the secrets to growing new giants. Learn more about this research.
Fires Were Common in Rainy Northern Forests
For years, Steve Norman had been told that the humid forests of coastal Northern California must be too wet to burn. Scientists who research fire acknowledge its power as a tool for reshaping the landscape, but some areas were considered nearly immune to fire. This assumption meant that the damp forests of Del Norte Coast Redwoods State Park remained a blank file in the coastal forest fire records. Learn more about this research.
Old Redwood Forest Restoration
Old-growth redwood forests are prized for their biological and aesthetic riches. If you’re a land manager trying to restore lands where redwoods have been logged, the old-growth forest is the ideal to which you aspire. But how do you move toward old-growth characteristics most efficiently? Learn more about this research.
Winter habitat crucial for coho salmon, spring for Chinook
The coho salmon population in Del Norte County’s Mill Creek depends heavily on the quantity and quality of winter habitat for survival, according to a study by The Rowdy Creek Fish Hatchery and a team of fisheries biologists. Learn more about this research.
Wonder Plot Study Tells Story of Development
In 1923 Emanuel Fritz, then a Professor of Forestry at UC Berkeley, and Woodbridge Metcalf secured for study a one-acre grove of second growth trees along the Big River in Mendocino County. By that year, much of California’s old-growth redwood had been logged and a second generation of trees had begun to grow. Fritz and Metcalf intended to study tree growth on their plot in order to better understand just how a second growth forest develops. Learn more about this research.
Prehistoric Fires Not Caused by Understory Grasses
Grassy fuels on the forest floor were not the cause of frequent prehistoric fires in giant sequoia (Sequoiadendron giganteum) groves, according to UC Berkeley researchers and California State Park ecologists. Learn more about this research.
Thinning Speeds Recovery to Old-Growth
Dr. Christopher Keyes and Andrew Chittick have found that thinning—removing select trees in a second-growth coast redwood forest—speeds up the forest’s development of old-growth characteristics, which include tall and bulky trees, small gaps in the canopy through which sunlight can penetrate, trees of varying heights, thicker tree branches, understory shrubs and ferns, and healthy young saplings. Learn more about this research.
Land Use and Forest Conservation
Dr. Sarah Marvin, professor of Geography at the University of Oregon, has set out to understand how the shape of the land and its use by owners reflect the probability of a privately owned coast redwood forest being protected. The two questions she has asked are: “Are privately owned forests more likely to be protected if they are on bigger parcels?” and “Do traditional, rural land uses as opposed to traditional, residential land uses promote forest preservation?” Answers to these questions might help predict the likelihood of future, private redwood forest protection and—of logged forests—regeneration. Learn more about this research.
Chemicals in Redwood Rings Indicate Past Water Uptake
It’s no coincidence that redwoods live in the thickest part of “California’s fog belt.” The presence of coastal summer fog has long been regarded a necessary ingredient for the health and perpetuation of coast redwood ecosystems. During drier summer months fog supplies trees with moisture and blocks the evaporating rays of direct sunlight, reducing the amount of water that redwoods lose via transpiration. What’s less understood, however, is exactly how fog frequency has varied in the past century and how redwoods have responded to this variation. Learn more about this research.
Bigger and Older Often Means Better Habitat
Traditionally we think of forest conservation as protection of large areas of land. Is it possible, though, that just one tree could benefit an ecosystem enough to warrant individual protection? Mary Jo Mazurek and William Zielinski report evidence that suggests legacy old-growth redwoods can do just that. Learn more about this research.
Big Trees: A Bank for Soil Bugs
Legacy trees, old-growth trees left standing in second-growth redwood forests, could serve as a habitat refuge for terrestrial microarthropods, miniscule bugs that live in the forest floor and maintain healthy soils, not to be confused with the bigger arthropods like spiders and bees. Dr. Michael Camann, Karen Lamoncha and Laura Hagenhauer have found substantially more and a wider variety of the soil bugs underneath these so-called legacy trees than beneath surrounding second-growth trees. Learn more about this research.
Bats in Giant Sequoias
Prior to this study, little was known about the bat community in Yosemite’s three giant sequoia groves and virtually nothing was known about how bats use the canopy in any of the Parks’ forests. Dr. Elizabeth Pierson, Dr. William Rainey, and Leslie Chow carried out major research to study bat roosting behavior in fire-scarred hollows at the base of sequoia trees, bat feeding behavior in association with a variety of habitats, and bat activity in the giant sequoia canopy. In addition, they combined observations from this study and others to describe the natural history of Yosemite’s 18 bat species. Learn more about this research.
Redwoods to the Sea Forest Carnivore Tracking Project
From time to time, a resident in Humboldt County will submit a report claiming to have spotted a Pacific fisher or a Humboldt marten. Because Pacific fishers are rare, and because the Humboldt marten was previously thought to be extinct due to human influences such as trapping and logging in their old-growth conifer habitat, these animals remain barely documented. The Corridor from the Redwoods to the Sea, built as a passageway for wild creatures, appears to be prime location to spot small carnivores such as fishers and martens, but despite local accounts, the rare sightings remain unverified by scientists. Where have these small predators gone? Learn more about this research.
Buffer and Let Be
Dr. William Russell found that the negative effects of timber harvesting in riparian coast redwood forests lessen with respect to two conditions; (1) longevity of the forest and (2) wider no-cut buffer zones. Longer-lived forests and forests with wider buffer zones surrounding rivers show less harm from logging. Riparian buffers are strips of forest left on either side of rivers after logging that control the amount of sediment and nutrients filtering into the water. In recently harvested forests and ones with thin or no buffers, young tree crowns crowd the canopies, letting through less sunlight, deciduous hardwoods thrive, extra dead wood litters the forest floors, and exotic and disturbance-prone understory species invade. These alterations, in addition to affecting the physical structure of rivers, down the line cause higher levels of organic material to filter into them. Learn more about this research.
Humboldt Martens Need Old Growth
It’s likely that Pacific fisher (Martes pennanti pacifica) populations are well distributed in Northern California’s Redwood National and State Parks (RNSP) for the same reason that Humboldt martens (Martes americana humboldtensis) have disappeared, according to research done by Keith Slauson, William Zielinski, and Gregory Holm. Second-growth forest habitats that cover a majority of the park are fishers’ sweet and martens’ sour. Learn more about this research.
Wandering Salamanders Choose Direct Route to Good Food
Wandering Salamanders (Aneides vagrans), in addition to dwelling on the ground, have been found in high-up patches of humus moss mats in trunk crotches, on limbs, under bark, and in the cracked and rotting wood of coast redwood trees. They may inhabit forest canopies, the researchers of this study speculate, because of a more profitable food resource available there. Learn more about this research.
What limits redwood height?
In the upper reaches of their crowns, coast redwoods struggle to lift water and nutrients into their leaves. This struggle begins a process that limits tree growth, according to a team of researchers studying redwoods in Prairie Creek and Humboldt Redwoods State Parks. Learn more about this research.
Sponge-like Mats Make Good Habitat in Redwood Canopies: Wandering Salamanders Benefit
Based on their research in Pairie Creek Redwoods State Park, Anthony Ambrose and Stephen Sillett have found that mats of humus soil deposited as high up as 265 feet in the crowns of coast redwood trees moderate the climate around them. This makes the mats habitable to a wide variety of insects and animals more commonly found on the forest floor. Learn more about this research.
Giant Sequoia Ecology Cooperative Web Site
Finding scientific resources on a specific plant species like the giant sequoia can be a daunting task. From the tangled network of information on the World Wide Web, the Giant Sequoia Ecology Cooperative Web site provides quick resources, ranging from maps and informational documents to expert contacts, which link the world to data on this rare tree, found only along the western slopes of the Sierra Nevada. Learn more about this research.
Balanced Management of Giant Sequoias
Giant sequoias are sometimes simply referred to as “big trees” and with good reason: They are the largest trees by volume and among the largest living things on Earth. These massive trees do not function in a void; they are supported by an intricate network of natural processes that keep the ecosystem working properly. Learn more about this research.
Epiphytes Provide High-Up Base for Biodiversity
William Ellyson and Stephen Sillett found evidence that demonstrates that epiphytes—plants that use other plants for mechanical support—play a crucial role in maintaining the biodiversity of redwood forest canopies. It’s well known that these hangers-on thrive in the old-growth Douglas-fir forests of Oregon and Washington, in places amassing the weight of two concert grand pianos per acre. Ellyson and Sillett reveal in this study that Douglas-fir has a rival in Sitka spruce, a tree that grows in and among northern coast redwood forests and supports a shockingly high diversity of epiphytes. Learn more about this research.
Bigger Preserves Have Better Chance to Prevail
Dr. William Russell, Dr. Joe McBride, and Ky Carnell have found that old-growth coast redwood forest reserves with areas larger in proportion to the length of their perimeters suffer fewer negative effects from exposed edges. Learn more about this research.
Bibliography Provides Easy Access to Coast Redwood Research
Coast redwoods have captivated scientists since their discovery, and thousands of articles, dissertations, and books have been written in an attempt to decipher various aspects of these magnificent trees. Finding all of this information was considerably more challenging until Deborah Rogers, a research geneticist and conservation biologist with the Genetic Resources Conservation Program at the University of California, Davis, stepped in to organize a bibliography of scientific materials written about coast redwoods in the past 50 years. Learn more.