Researchers map symbiotic relationships between trees and microbes worldwide

by Taylor Kubota, Stanford University
In and around the tangled roots of the forest floor, fungi and bacteria grow with trees, exchanging nutrients for carbon in a vast, global marketplace. A new effort to map the most abundant of these symbiotic relationships—involving more than 1.1 million forest sites and 28,000 tree species—has revealed factors that determine where different types of symbionts will flourish. The work could help scientists understand how symbiotic partnerships structure the world’s forests and how they could be affected by a warming climate.

In and around the tangled roots of the forest floor, fungi and bacteria grow with trees, exchanging nutrients for carbon in a vast, global marketplace. A new effort to map the most abundant of these symbiotic relationships—involving more than 1.1 million forest sites and 28,000 tree species—has revealed factors that determine where different types of symbionts will flourish. The work could help scientists understand how symbiotic partnerships structure the world’s forests and how they could be affected by a warming climate.

Source: Researchers map symbiotic relationships between trees and microbes worldwide – Phys.org, 2019-05-15

Can Humans Help Trees Outrun Climate Change?

By Moises Velasquez-Manoff
A dark synergy of extreme weather and emboldened pests could imperil vast stretches of woodland. Foresters are only starting to wrestle with solutions.

Foresters began noticing the patches of dying pines and denuded oaks, and grew concerned. Warmer winters and drier summers had sent invasive insects and diseases marching northward, killing the trees.

If the dieback continued, some woodlands could become shrub land.

Most trees can migrate only as fast as their seeds disperse — and if current warming trends hold, the climate this century will change 10 times faster than many tree species can move, according to one estimate. Rhode Island is already seeing more heat and drought, shifting precipitation and the intensification of plagues such as the red pine scale, a nearly invisible insect carried by wind that can kill a tree in just a few years.

The dark synergy of extreme weather and emboldened pests could imperil vast stretches of woodland.

So foresters in Rhode Island and elsewhere have launched ambitious experiments to test how people can help forests adapt, something that might take decades to occur naturally. One controversial idea, known as assisted migration, involves deliberately moving trees northward. But trees can live centuries, and environments are changing so fast in some places that species planted today may be ill-suited to conditions in 50 years, let alone 100. No one knows the best way to make forests more resilient to climatic upheaval.

These great uncertainties can prompt “analysis paralysis,” said Maria Janowiak, deputy director of the Forest Service’s Northern Institute of Applied Climate Science, or N.I.A.C.S. But, she added, “We can’t keep waiting until we know everything.”

Source: Can Humans Help Trees Outrun Climate Change? – New York Times, 2019-04-25

Hidden giants in forest soils

Only a fraction of the microbes residing in, on and around soils have been identified through efforts to understand their contributions to global nutrient cycles. Soils are also home to countless viruses that can infect microbes, impacting their ability to regulate these global cycles. In Nature Communications, giant virus genomes have been discovered for the first time in a forest soil ecosystem by researchers from the DOE Joint Genome Institute and the University of Massachusetts-Amherst.

Characterizing the diversity of microbial cells in a handful of soil is so complex it was considered impossible. To date, only a small fraction of the microbes residing in, on and around soils have been identified as part of efforts to understand their contributions to the global carbon cycle, and to other nutrient cycles. Soils are also home to countless viruses that can infect microbes, impacting their ability to regulate these global cycles.

Reported November 19, 2018, in Nature Communications, giant virus genomes have been discovered for the first time in a forest soil ecosystem by researchers from the U.S. Department of Energy (DOE) Joint Genome Institute (JGI), a DOE Office of Science User Facility, and the University of Massachusetts-Amherst (UMass Amherst). As the name implies, giant viruses are characterized by disproportionately large genomes and virions that house the viruses’ genetic material. They have been frequently found within protists and algae, and thus they are believed to have a significant impact on their hosts’ population dynamics and the planet’s biogeochemical cycles.

Source: Hidden giants in forest soils – EurekAlert, 2018-11-19

Take a Look at How Quickly a Forest Can Recover From Fire

By Andy Newman
Though it appears destructive, fire in the New Jersey Pinelands is a force of renewal.
On April 22, a spring wildfire roared through Penn State Forest in the New Jersey Pine Barrens, sending 100-foot flames shooting from the crowns of the pitch pines. The fire consumed half a square mile in 40 minutes and could be seen from space. By the time the New Jersey Forest Fire Service got it under control, it had burned 843 acres, an area the size of Central Park.

A week later, even as ash still swirled through air heavy with the creosote scent of burned resin and a cedar log smoldered at the edge of a swamp, the forest was being reborn. Pine cones that open only under extreme heat had released their seeds. Though the trees themselves were charred, almost all survived the fire. Where chest-high blueberry and huckleberry had burned down to pointy stubs, tufts of grass were sprouting.

Destructive fires in the West dominated the news this summer, but for eons fire has been not just an inevitable feature of the landscape, but essential to the forest’s health and continuity. In the vast wilderness of the Pine Barrens, the forest regenerates so fast that scientists studying the physics of fire use it as a laboratory.

Eleven weeks after the fire in Penn State Forest, at the height of summer’s greening, new blueberry bushes were already shin high. A grass that flowers only after fire had put forth purple-brown seeds. And scattered all through the fire site, bursts of bright-green pitch-pine needles grew straight out of scorched trunks.

Source: Take a Look at How Quickly a Forest Can Recover From Fire – New York Times, 2018-09-25

Scientists thought they had created the perfect tree. But it became a nightmare.

By Adrian Higgins
A pear seedling selection named Bradford was cloned by the gazillion to become the ubiquitous street tree of America’s postwar suburban expansion. Then it turned invasive.

Carole Bergmann pulls her small parks department SUV into an aging 1980s subdivision in Germantown, Md., and takes me to the edge of an expansive meadow. A dense screen of charcoal-gray trees stands between the open ground and the backyards of several houses. The trees are callery pears, the escaped offspring of landscape specimens and street trees from the neighborhood. With no gardener to guide them, the spindly wildlings form an impenetrable thicket of dark twigs with three-inch thorns.

Bergmann, a field botanist for the Montgomery County Parks Department, extricates herself from the thicket and in the meadow shows me that what I take to be blades of grass are actually shoots of trees, mowed to a few inches high. There are countless thousands, hiding in plain sight in Great Seneca Stream Valley Park. If it were not cut back once a year, the meadow would become like the adjacent screen, wall upon wall, acre upon acre of black-limbed, armored trees worthy of Sleeping Beauty’s castle.

“You can’t mow this once and walk away,” said Bergmann, who began her 25-year career in the department as a forest ecologist but has been consumed by an ever-pressing need to address the escape of the Bradford pear and other variants of callery pear, a species that originated in China, along with other invasive exotics.

Source: Scientists thought they had created the perfect tree. But it became a nightmare. – The Washington Post, 2018-09-17

Loosing the forest for the trees – the tragedy of modern forestry

By Dr. Ranil Senanayake
What is known by science reveals the forest as an ecosystem of tremendous complexity. The trees, while providing the essential framework of a forest constitutes only a fraction of the total biodiversity. It contains a huge array of organisms, that continually change in form and function. Thus biodiversity is what gives a forest its identity. It should also be borne in mind that, from the small bushes of an area after a fire to the tall growth fifty years later, the species and architecture goes through many changes, and all these ecosystems are expressions of the growing, maturing forest.

The international response to the loss of natural forest ecosystems can be seen in the massive global investment in forestry. However, a great majority of these revegetation programs around the world do not seem to provide an environment that is hospitable for sustaining local forest biodiversity. A situation brought about by neglect of the ecological and biodiverse reality of a forest in project planning. There is no excuse to be found in the argument that there was no information. Forest Ecology has a long and distinguished history in the scientific literature. The result of this neglect was that institutional forestry activity was centered around the growing of even aged monocultures of fast growing trees with no requirement to attend to the rehabilitation of forests.

The discussions on the sustainable management of forests still lack clear definitions creating a sense of confusion in the identification of goals. For instance, the inability to distinguish between plantations and forests have allowed processes that have led to a massive reduction of forest biodiversity. A clear definition of ‘a Forest’ needs to be clarified and harmonized in statements transmitted from the CBD to the IPF or the CSD. As forests are biological entities, any criteria or indicator chosen to represent biodiversity status must be rooted in biological variables. The current practices of assessing physical cover alone will not adequately indicate forest quality and trends. In this context, socio-cultural values should also be incorporated into the setting of criteria and indicators. Further, for every acre of forest that stands today, hundreds of acres of forest have been lost in the surrounding countryside. Yet there has been no mention of the need for rehabilitation and recovery of the biodiversity status of such degraded lands. If these fundamental issues are not addressed, the loss of forests and biodiversity in these critical ecosystems cannot be contained.

Source: Loosing the forest for the trees – the tragedy of modern forestry. Forests-Beyond The Wood IV. – The Island, 2018-09-07

The lodgepole pine is the poster child of Yellowstone’s plant recovery

By Brett French
If there’s a plant-based poster child for wildland fire in the subalpine forests of Yellowstone National Park, it would be the cone of the lodgepole pine tree.

“All of these forests evolved with fire after the last glacial retreat,” said Roy Renkin, a vegetation specialist for Yellowstone National Park. “Different species have evolved different mechanisms to deal with fire.”

The Douglas fir has thick bark meant to resist low-intensity fires. Fireweed spends a lot of time spreading its roots out so it can sprout after fires remove competition. And the lodgepole pine’s specially devised cones will open to release seeds only when heated to 104 to 122 degrees.

“This green forest over here looked like that black forest many times,” he explained.

Surprises
Renkin is one of the few people still on staff at Yellowstone who was around when the 1988 fires swept across roughly one-third of the park, charring more than 793,000 acres. Since then, he’s been witness to the rebirth of the park’s vegetation following what many at the time thought would be a legacy of scorched earth and a slow rebound.

“You guys will be lucky to have a meadow there in 100 years,” let alone a forest, he remembers one group of “ologists” concluding after visiting a heavily burn site. Thirty years later some of the trees that repopulated the area are 25 feet tall. Elk sedge that took root has grown “as big as basketballs.”

Source: The lodgepole pine is the poster child of Yellowstone’s plant recovery – The Missoulian, 2018-08-28

Logging site slash removal may be boon for wild bees in managed forests

New research suggests the removal of timber harvest residue during harvesting may be a boon for wild bees, an important step toward better understanding the planet’s top group of pollinators.

The findings are important because bees are the driving force behind $100 billion in global economic impact each year, with insect pollinators enhancing the reproduction of 90 percent of the Earth’s flowering plants, including many food crops.

Insect pollinators are also ecologically critical as promoters of biodiversity. Bees are the standard bearer because they’re usually present in the greatest numbers and because they’re the only pollinator group that feeds exclusively on nectar and pollen their entire life.

Researchers at Oregon State University spent two years studying 28 contiguous 1-acre clearcut sites. They assessed whether the abundance and diversity of wild bees was affected by the removal of timber harvest residue, also known as slash, and the soil compaction that goes along with it.

“Bees are important for biodiversity in managed forest landscapes but we just don’t have a very good handle on them in these areas,” said lead scientist Jim Rivers of the OSU College of Forestry.

The study plots occurred within a managed conifer forest in western Oregon. Each plot received one of five unique treatments, ranging from removing only the boles – tree trunks that are used to make lumber – without compacting the soil at all (no heavy equipment used on the plot) to removing all of the logging slash and compacting the entire plot.

The findings were surprising, Rivers said.

“The combination of the most intense timber residue removal and soil compaction treatment made for the greatest number and diversity of bees,” he said.

Source: Logging site slash removal may be boon for wild bees in managed forests – EurekAlert!, 2018-08-15

Satellite imagery helps monitor Bavarian forest

Things are looking up in a swath of forest in southern Germany, thanks to innovative funding from the European Union for a project that aims to help policymakers better understand how the forest’s ecosystems work.

The ECOPOTENTIAL project uses satellite images for ecosystem modelling in 25 Protected Areas in Europe (as well as Kenya, the Caribbean and Israel) to address climate change and other threats to ecosystems. In the Bavarian forest, the images and mathematical models of ecosystems, or “Earth Observation tools”, are helping to assess the impact of climate change and pollution, and shape national protection policies.

UN Environment is one of many partners supporting the 2015-2019 ECOPOTENTIAL project, funded by the European Union to the tune of 16 million euros.

Within the ECOPOTENTIAL project, Earth Observation tools and “remote sensing”, including by aircraft and drones, are being used to better understand how vegetation is evolving across the park and over time.
Satellite and drone pictures are detecting patterns of dominant plant species, linking habitat characteristics with terrain, and tracking animal movements. The park administration is also carrying out intensive research on tree regeneration, the role of dead wood, and the impact of global warming and extreme climatic events on the future development of these ecosystems.

Source: Satellite imagery helps monitor Bavarian forest – UN Environment, 2018-08-15