Cutting down trees inevitably leads to more carbon in the environment, but deforestation’s contributions to climate change are vastly overestimated, according to a new study.
Deforestation for timber and farmland is responsible for about 92 billion tons of carbon emissions into the environment since 1900, found a study led by researchers at The Ohio State University and Yale University.
“Our estimate is about a fifth of what was found in previous work showing that deforestation has contributed 484 billion tons of carbon – a third of all manmade emissions – since 1900,” said Brent Sohngen, a professor of environmental and resource economics at Ohio State.He said that widely accepted estimate didn’t take into account the planting of new trees and other forest management techniques that lessen the environmental burden. The model used in this study did take those factors into account, which made a significant difference considering the intensive forest management happening in many parts of the world and the less-intensive, but not inconsequential, management that is happening elsewhere.
The study appears today (Nov. 4, 2019) in the Journal of Forest Economics.
“There was a significant shift toward treating forests as a renewable, rather than nonrenewable, resource in the last century, and we estimate that those reforestation and forest management efforts have led to a far smaller carbon burden on the environment,” Sohngen said, adding that the previous estimate was based on trees’ natural regrowth without any human intervention.
By Soyeon Bae, et al
Recent progress in remote sensing provides much-needed, large-scale spatio-temporal information on habitat structures important for biodiversity conservation. Here we examine the potential of a newly launched satellite-borne radar system (Sentinel-1) to map the biodiversity of twelve taxa across five temperate forest regions in central Europe. We show that the sensitivity of radar to habitat structure is similar to that of airborne laser scanning (ALS), the current gold standard in the measurement of forest structure. Our models of different facets of biodiversity reveal that radar performs as well as ALS; median R² over twelve taxa by ALS and radar are 0.51 and 0.57 respectively for the first non-metric multidimensional scaling axes representing assemblage composition. We further demonstrate the promising predictive ability of radar-derived data with external validation based on the species composition of birds and saproxylic beetles. Establishing new area-wide biodiversity monitoring by remote sensing will require the coupling of radar data to stratified and standardized collected local species data.
By Michelle Ma
About 450 nonnative, plant-eating insect species live in North American forests. Most of these critters are harmless, but a handful wreak havoc on their new environment, attacking trees and each year causing more than $70 billion in damage.
The problem is, scientists often don’t know which insect will emerge as the next harmful invader.
A team led by the University of Washington, drawing largely on the evolutionary history of insect-plant interactions, has developed a way to understand how nonnative insects might behave in their new environments. The team’s model, described in a paper appearing Oct. 17 in the journal Ecology and Evolution, could help foresters predict which insect invasions will be problematic, and help managers decide where to allocate resources to avoid widespread tree death.
“What makes the bad invaders so special? That has been the million-dollar question, for decades,” said Patrick Tobin, an associate professor in the UW School of Environmental and Forest Sciences and one of the project leaders. “This has the potential to profoundly change how we predict the impact of nonnative species and prioritize limited resources used to mitigate these impacts.”
The new model can quickly evaluate whether a newcomer insect, even before it gets here, has a high probability of killing a population of North American trees. To use the model, all that’s needed is information about the insect’s feeding method (wood, sap or leaf feeder, for example) and what trees it feeds on in its native range. The model will then determine whether any North American trees are at risk of dying from it.
Whether a nonnative insect takes hold and becomes destructive has more to do with the evolutionary history between the new (North American) host tree and the insect’s native host tree from its home region, Mech explained. Molecular tools that allow scientists to construct comprehensive phylogenies (or maps) of how tree species evolved was key to the team’s breakthrough.
For example, if a pine tree in Asia and another in North America diverged tens of millions of years ago, the North American pine likely wouldn’t have retained defenses against an insect that only lives with the pine in Asia. Alternatively, two pines on both continents that share more evolutionary history and diverged more recently might still share similar defenses.
The new model helps identify the evolutionary “perfect storm” for conifers, where the invasive insect still recognizes the new tree as a food source, but the tree hasn’t retained adequate defenses to keep the invader in check.
Sometime later this month or in early November, if the weather cooperates, the U.S. Forest Service will fly a pair of fire-spitting helicopters over a remote mountain in southern Utah and set the forest ablaze.
While the helicopters are pelting burning liquid fuel at the treetops, dozens of firefighters will be providing support on the ground, using drip torches and flamethrowers to create a towering wall of flame that will stretch from the forest floor to the sky. As the heat builds and the blaze roars across spruce- and fir-stippled canopies, a small army of scientists will launch weather balloons and drones, drive radar- and LIDAR-equipped trucks around the perimeter, fly specialized research planes overhead, and gather data on fire-hardened GoPro cameras to analyze the inferno from start to finish.
It will be among the fiercest controlled burns scientists have ever studied in the wild—“as close to a wildfire as you can expect,” says Roger Ottmar, the principal investigator for the Forest Service–led Fire and Smoke Model Evaluation Experiment (FASMEE). The goal? To collect data on every aspect of the fire at once, in order to improve the models scientists and land managers use to predict the impacts of fires. That will allow the agency to oversee more controlled burns on landscapes that need fire to thrive, and the data will also provide insight into the large, intense blazes that keep erupting across the West—the types of unruly fires that climate change and changing land-use patterns are making more common.
“The more experiments we can do, the better we can understand fire behavior in a changing climate,” says Craig Clements, the director of the Fire Weather Research Laboratory at San Jose State University and the science lead for FASMEE’s plume-dynamics and meteorology team. “This is the opportunity of a lifetime.”
The opportunity exists only because of the very specific ecological challenges facing Fishlake National Forest’s Monroe Mountain. The upcoming burn is part of a larger restoration project the Forest Service launched back in 2015 to revive the area’s ailing aspens, explains Linda Chappell, the regional fuels program manager. These trees, which provide food and shelter for a wide array of animals, including elk, rabbits, porcupines, beavers, and countless birds, have been declining across the West for decades due in part to overgrazing by deer and livestock. Drought and disease have hit hard, too. And aspens, a clonal species, need wildfires to cue their roots to put out new “suckers,” or sprouts. Around Monroe Mountain, the frequency of wildfires has dropped dramatically over the past century, allowing a mix of conifer species to slowly take over.
One of the most effective ways to bring aspens back is to ignite a “crown fire”: a really big, really hot fire that jumps from treetop to treetop and sends flames writhing upward into the sky. The work is being done piecemeal over the course of a decade in order to introduce as much variation as possible into the mountain ecosystem. “We want a crazy quilt of aspen ages and a crazy quilt of conifer ages,” Chappell says. Because these prescribed crown fires are so similar to wildfires in terms of their intensity, the restoration project served as the ideal natural laboratory for FASMEE to piggyback onto.
By Nicky Ouellet
As fire season winds down, managers are intentionally setting fire to brush piles, slash and even large sections of forests in an effort to prevent out of control wildfires in future seasons. A group of scientists from Montana and Idaho recently published a paper arguing that strategies like these should be part of a radical rethinking of how people in the West live with fire.
Dave McWethy says Montana has passed a tipping point. Summers are hotter and drier, which means fire season lasts longer. Our approach to put every single fire out, like we’ve done for the past 100 years, just isn’t realistic anymore.
“The big take home message is that we can’t respond the way we have in the past to wildfire,” McWethy said.
McWethy is an assistant professor of earth sciences at Montana State University. In a recent article in Nature Sustainability, McWethy and his coauthors argue that people living in the West need to reconsider how we live with, and even harness, fire if we want to continue living here in the future.
“We have to make changes. And one of the great things we have to do that, is how we used to use fire as a tool in the past,” McWethy said.
McWethy’s team found a model in the Netherlands, where instead of fighting rising sea levels with taller and taller dams, engineers built an infrastructure system designed to work with water instead of fight it.
“And instead of rebuilding in the same way that they have in the past, they’ve decided to transform how they accept or live with these hazards… It’s coming back to this idea that fire is part of Western landscapes, it was in the past it is today and it’s going to be in the future. And I think becoming comfortable with the fact that with warming temps and a longer fire season, the best way we can move into the future is accept fire as a natural process, and start to think about how we could use fire itself to safeguard our communities,” McWethy said.
By Madeline K. Sofia, Maia Stern, and Becky HarlanNalini Nadkarni was one of the first people to study the canopy — the part of trees just above the forest floor to the top branches. Her discoveries have helped shape our understanding of forests.
Then in 2018, more than a decade after Nadkarni started TreeTop Barbie, she got an unbelievable phone call. National Geographic had partnered with Mattel to make a series of Barbies focused on exploration and science. And they wanted Nadkarni to be an advisor.
By Al Parker
It might seem out of place, and it certainly lives under the radar of tourists and locals alike, but Grayling’s W.J. Beal Tree Plantation might be the oldest documented experimental tree plantation in North America.
Situated inside the city’s industrial park and surrounded by the daily bustle of commerce, this placid, historic green space, on many days, is seen only by delivery truck drivers and workers who rumble along Industrial Park Road, unaware of the significance of the towering pine trees they pass.
“This site might be the only one in the country where reforestation has been so well documented and preserved over more than 100 years,” wrote Frank Telewski, a Michigan State University professor of plant biology, at the site’s dedication in 1997.
Once 80 acres, the site is now only about 5 acres, but it’s filled with towering pine trees that stand as testament to the foresight of William James Beal, a bearded, burly, and bold visionary who taught botany and horticulture at the Michigan Agricultural College (MAC), now Michigan State University, from 1871 to 1910. A pioneer of what came to be called “The New Botany,” Beal extolled independent learning through observation.
“In the 1800s we did not know how to grow and plant trees,” said Susan Thiel, a now-retired Department of Natural Resources Forest Manager who managed the Beal Tree Plantation. “Professor Beal did vast experimentation across several different sites to learn how to collect seed, plant and germinate it, and grow trees of different varieties. This site helped develop the science of growing and regenerating trees and reforesting sites as we know it today.”
Beal’s Grayling Agricultural Experiment Station offered unique promise: Its 80 acres came courtesy of the Michigan Central Railroad Company, which had donated the “wild land” to MAC — land that had been cut and exposed to fire, which left a scattering of random jack pines and oak root sprouts. The Grayling location became the “base substation,” wrote Beal “because the area’s climate and conditions would represent the average — neither the best nor the poorest of the sterile land.”
Moving quickly, Beal supervised the cleaning and preparation of the ground. A barbed wire-and-board fence was built to keep cattle and animals away, while a 5-foot strip of ground was plowed along both sides of the fence to deter fires from entering the property.
By May of 1888, Beal had directed the planting of 2,145 seedlings, which came from W.W. Johnson of Antrim County. The seeds were planted in 14 rows, each row precisely four feet apart. Along the north side and south sides, 20 acres each were designated for agricultural experiments.
Beal would not have long to watch his seedling and saplings grow; in 1891, Beal was relieved of his work at the plantation and was replaced the following year by Dr. O. Palmer.
In 1997, an inventory was taken; it showed that of the 41 species started as seedlings or seeds in 1888 and 1889, no hardwoods survived. But original stems from seven of nine conifers endured, mostly red pine and white pine. They stand there still today, silently and majestically greeting visitors to the Beal Tree Plantation.
The plantation is open to the public, free to enter, and features a handicap-accessible path for visitors to explore. There are a few weathered signs that offer information, a couple of benches along the needle-strewn path, and limited parking. Find a map at www.michigan.org/property/wj-beal-tree-plantation.
By Chrissy Sexton
Professor Matthew Evans from the University of Hong Kong created a computer model to estimate how ash dieback disease may affect the UK’s 125 million ash trees.
Human-induced changes to the environment are increasing the rate at which pests and diseases are introduced, which is severely threatening to native species. Long-lived species that reproduce slowly, such as forest trees, are particularly susceptible to new pathogens.
It is estimated that in 2015, 100 million hectares of forest were affected by pests and diseases around the globe. However, the subsequent impacts to any given forest ecosystem cannot be detected for years, so experts use computer models to predict future outcomes.
In a recent study, Professor Matthew Evans from the University of Hong Kong created a computer model to estimate how ash dieback (ADB) disease may affect the UK’s 125 million ash trees.
ADB disease, which is caused by a fungus native to East Asia, was introduced to the UK seven years ago. This incurable infection leaves diamond-shaped scars on the bark and causes the leaves to fall off of the trees.
About one in every 100 ash trees is able to resist the fungus and avoid infection. This is likely due to a genetic advantage which allows the trees to shed their leaves earlier to prevent the fungus from establishing itself.
Professor Evans found that at the current level of resistance, 95 percent of the UK’s ash trees could be wiped out by the end of the century. He determined that breeding more ash trees with resistance will prevent millions of deaths.
By Lex Treinen
ANCHORAGE (KTUU) – Scientists have been working feverishly to understand the processes that drive wildfires in the state and in the country, and unsurprisingly there is some worrying news about chance of big fires in the future.
While national agencies offer predictions the data is pretty coarse without nuance to the terrain or ecology of an area.
So researchers like Peter Bieniek of UAF are working to produce better models to increase the accuracy of forecasts and models, particularly on a large scale and in longer time frames. Beniek’s work focuses on analyzing data for future, high-probability fire days, and the results aren’t much of a surprise considering a warming planet.
“Likely looking down the road, especially in these future projections, data show that we’re gonna get more higher fire danger over the next hundred years,” says Bieniek.
One of the main drivers of higher probability is a likely increase in lightning strikes in Interior Alaska, which is caused by a higher likelihood of convective precipitation. Convective precipitation occurs when water vapor rises straight up through the atmosphere to form clouds, instead of moving diagonally like normal weather patterns that bring various forms of precipitation.
That moves the total likelihood of a fire year like 2015 — when five million acres burned — higher by 34 to 60%, according to Bieniek’s data.
Bieniek’s data show that these sorts of strikes are likely to increase as convection precipitation increases. That, in turn, drives up the likelihood of fires.
An interesting finding is that two different models used by Bieniek and his colleagues indicate that while fire danger is likely to rise in the early season–May, June, and July– the models diverge as to whether the fire danger will stay as high in August and September. That means that fire managers could be seeing intense strain on firefighting crews earlier in the season, and have it taper off later in the season. For now, though, they aren’t making any bets.
By Rob Jordan
It costs more than a new iPhone XS, and it’s made out of hazelnut shrub stems. Traditional baby baskets of Northern California’s Yurok and Karuk tribes come at a premium not only because they are handcrafted by skilled weavers, but because the stems required to make them are found only in forest understory areas experiencing a type of controlled burn once practiced by the tribes but suppressed for more than a century.
A new Stanford-led study with the U.S. Forest Service in collaboration with the Yurok and Karuk tribes found that incorporating traditional techniques into current fire suppression practices could help revitalize American Indian cultures, economies and livelihoods, while continuing to reduce wildfire risks. The findings could inform plans to incorporate the cultural burning practices into forest management across an area one and a half times the size of Rhode Island.
“Burning connects many tribal members to an ancestral practice that they know has immense ecological and social benefit especially in the aftermath of industrial timber activity and ongoing economic austerity,” said study lead author Tony Marks-Block, a doctoral candidate in anthropology who worked with Lisa Curran, the Roger and Cynthia Lang Professor in Environmental Anthrolopogy.
“We must have fire in order to continue the traditions of our people,” said Margo Robbins, a Yurok basket weaver and director of the Yurok Cultural Fire Management Council who advised the researchers. “There is such a thing as good fire.”
The study, published in Forest Ecology and Management, replicates Yurok and Karuk fire treatments that involve cutting and burning hazelnut shrub stems. The approach increased the production of high-quality stems (straight, unbranched and free of insect marks or bark blemishes) needed to make culturally significant items such as baby baskets and fish traps up to 10-fold compared with untreated shrubs.
Reducing fuel load
Previous studies have shown that repeated prescribed burning reduces fuel for wildfires, thus reducing their intensity and size in seasonally dry forests such as the one the researchers studied in the Klamath Basin area near the border with Oregon. This study was part of a larger exploration of prescribed burns being carried out by Stanford and U.S. Forest Service researchers who collaborated with the Yurok and Karuk tribes to evaluate traditional fire management treatments. Together, they worked with a consortium of federal and state agencies and nongovernmental organizations across 5,570 acres in the Klamath Basin.
The consortium has proposed expanding these “cultural burns” – which have been greatly constrained throughout the tribes’ ancestral lands – across more than 1 million acres of federal and tribal lands that are currently managed with techniques including less targeted controlled burns or brush removal.