Tag Archives: forests

Africa’s Forests Are Currently Emitting More CO2 Than They Absorb

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Congo’s rainforest ranks as the second largest globally

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Africa’s forests currently release more carbon dioxide than they can absorb, complicating global efforts to achieve net-zero emissions.

The continent’s forests and shrublands were once among the largest carbon sinks, contributing to 20% of all carbon dioxide absorption by plants. The Congo rainforest, the second largest in the world after the Amazon, is often termed the “lungs of Africa,” absorbing roughly 600 million tons of CO2 each year. Unfortunately, this vital ecosystem is diminishing due to logging and mining activities.

Recent research indicates that Africa’s forests lost an annual average of 106 million tonnes of biomass between 2011 and 2017, following a period of growth from 2007 to 2010. This loss translates to approximately 200 million tons of CO2 emissions annually, primarily linked to deforestation in the Congo. Heiko Balzter from the University of Leicester, UK, highlights this concerning trend.

“To lose tropical forests as a means of mitigating climate change means we must significantly reduce emissions from fossil fuel burning and strive for near-zero emissions,” he states.

Balzter and his team utilized satellite data to measure aspects like canopy color, water content, and height at selected locations to calculate biomass levels. These findings were compared to on-the-ground measurements, although such data are scarce in Africa.

However, Simon Lewis from University College London cautions that satellite technology cannot accurately identify tree species within a forest and fails to reliably estimate carbon absorption in forests with high biomass or emissions from those compromised by selective logging. For example, a dense hardwood like mahogany retains more carbon than a lighter wood like balsa of equivalent size.

“Deforestation rates in the Democratic Republic of Congo have surpassed those of the 2000s, a fact we cannot deny,” he asserts. “Nonetheless, it remains uncertain if this will significantly alter the carbon balance across the continent.”

The study also overlooks the wet peatlands that lie beneath much of the Congo rainforest. These peatlands absorb modest quantities of CO2 annually and sequester around 30 billion tonnes of ancient carbon.

In recent years, the Amazon rainforest, once a significant carbon sink, has emitted more CO2 than it absorbs. While deforestation in the Amazon is somewhat regulated, the situation is worsening in Congo.

In the Democratic Republic of Congo, impoverished farmers often clear rainforests for slash-and-burn agriculture, while many foreign-owned companies engage in illegal logging of valuable hardwoods such as African teak and coralwood.

During the recent COP30 climate summit in the Amazon, Brazil unveiled the Tropical Forests Forever Facility, a fund designed to provide investment returns to tropical nations at the rate of $4 per hectare of remaining forest. However, contributions to this fund have only reached $6.6 billion, a fraction of the $25 billion target.

Balzter believes this initiative could be more effective than carbon credits, which reward “avoided” emissions that often lack real value.

“It’s crucial to establish this tropical forest permanent facility swiftly if we intend to reverse the trend of increased carbon emissions from Africa’s tree biomass,” he emphasizes.

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Source: www.newscientist.com

Forests with Healthy Wildlife Populations Store Four Times More Carbon

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Capuchin Monkeys and Their Role in Seed Dispersal in Tropical Forests

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Tropical ecosystems, rich in animal biodiversity that aids in seed dispersal, can sequester carbon at rates up to four times higher than fragmented forests lacking these animals or where their movements are limited.

“This underscores the connection between the loss of animal biodiversity and the processes that intensify climate change,” explains Evan Fricke from the Massachusetts Institute of Technology. “We’ve lost the potential for tropical forest regeneration.”

While animals only store a fraction of the carbon in their environment, their activities significantly influence ecosystem carbon dynamics. Notably, species such as monkeys, birds, and rodents play a crucial role in dispersing a wide variety of seeds.

Fricke mentions that “linking this to a prolonged process like carbon capture across landscapes proved quite challenging.”

Fricke and his team examined over 3,000 plots in tropical forests where trees are returning and successfully reabsorbing carbon following disturbances. They then assessed the degree of movement and diversity disruption of seed-dispersing animals in each plot, with findings influenced by forest fragmentation and data from monitored animals.

They discovered that increased disruption in seed disperser movement correlated with lower rates of carbon accumulation. The forests with the most disturbed animal behaviors grew four times faster than those with minimal disruption.

On average, disturbances in animal diversity and movement patterns that disperse seeds halved the carbon accumulation potential of affected plots. This indicates that such disruptions had a more detrimental impact than other factors inhibiting tree regrowth, such as fires and livestock grazing.

In contrast, forests experiencing the least disruption sequestered carbon more rapidly than monoculture wood farms. “Natural growth enhanced by animal activity presents a cost-effective and biodiversity-friendly recovery method,” states Fricke.

Earlier ecological models indicated that seed dispersers might significantly influence carbon storage; however, this study further elucidates the critical role these animals play, according to Oswald Schmitz from Yale University. “It highlights their importance now and into the future.”

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Source: www.newscientist.com

Declining Snowcover in Forests Poses a Threat to Carbon Storage

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Forests similar to Vermont’s Mansfield State Forest are experiencing snow loss

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Many forests are losing their winter snowpacks due to rising global temperatures, which can significantly hinder growth and diminish the capacity to absorb carbon dioxide from the atmosphere.

Current predictions suggest that these expectations may overestimate future carbon storage, as they fail to account for the complexities linked to winter climate shifts, according to Emerson Conrad Rooney from Boston University, Massachusetts.

Rising temperatures generally promote growth in temperate forests by enhancing decomposition and nutrient availability during warmer seasons. However, the model primarily overlooks winter changes, especially snow loss.

“The diminishing deep and insulating snowpacks cannot merely be seen as a minor change,” says Elizabeth Burakowski at the University of New Hampshire. Her findings indicate that such changes impact water storage and the health of ecosystems, warning that deep snow days could vanish from much of the U.S. by century’s end.

To better understand these cold-weather impacts, Conrad Rooney and his team modeled the effects of a 5°C increase in global temperatures on the growth of red maple trees (Acer rubrum) in a New Hampshire experimental forest. Some plots were treated with buried cables to warm the soil during the growing season, while others had their snow removed in winter, which warmed the soil and created conditions for freeze-thaw cycles.

Over a decade, trees in both scenarios exhibited more growth than those left undisturbed. However, the areas devoid of snow experienced a significant reduction in growth, halving their typical increase. Researchers attribute this disparity to root damage from exposing the soil to temperature fluctuations without snow cover.

“Snow acts as an insulating blanket, keeping the soil from freezing,” explains Conrad Rooney. “Less snow means an increase in freeze-thaw cycles.”

When researchers projected similar outcomes for northeastern U.S. forests, they estimated an anticipated loss of snowpacks by the century’s end could result in a decrease in carbon storage by about one million tons annually, in contrast to models that do not incorporate the implications of snow loss.

“The fluctuating presence of snow throughout winter undermines the stable soil conditions essential for the long-term carbon storage needed by northeastern ecosystems,” states Burakowski.

However, it’s important to note that not all snowy forests react similarly to snow loss as the deciduous trees found in the Northeast. David Bowling from the University of Utah emphasizes the necessity for accurate modeling of different ecological responses, noting, “There are many changes occurring.”

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Source: www.newscientist.com

Ancient forests hidden beneath the Rocky Mountains emerge as ice melts.

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exposed white bark pine

Gregory Pederson

Melting ice in the Rocky Mountains has led to the discovery of a 5,900-year-old white bark pine forest. Scientists discovered more than 30 trees during an archaeological survey on Wyoming's Beartooth Plateau at about 3,100 meters above sea level, 180 meters above the current tree line.

This, he says, “allows us to learn about past conditions at high altitudes.'' Kathy Whitlock at Montana State University. Japanese white pine (Albicari pine) These plants needed to grow during warmer weather, she says, because they don't currently grow at this elevation.

To understand the history of the lost forests, Whitlock's team analyzed tree rings and used carbon dating to find out how old the forests were. They discovered that the tree lived between 5,950 and 5,440 years ago, a time when temperatures were steadily dropping.

Data from ice cores in places like Antarctica and Greenland suggest that these temperature drops were influenced by centuries of volcanic eruptions in the Northern Hemisphere. These produced enough aerial deposits to block sunlight and lower global temperatures until the environment became too cold for these high-altitude trees to survive.

Although the newly discovered tree was lying flat, it was in exceptional condition, indicating that it was rapidly preserved after death. Although there is no evidence of avalanche cover, there are traces consistent with the current expansion of the ice sheet.

Climate models suggest that more continuous volcanic eruptions occurred in Iceland 5,100 years ago, causing further temperature drops, team members say Joe McConnell at the Desert Research Institute in Nevada. These temperature drops led to the expansion of the ice belt, and “the fallen trees were buried in the ice and protected from the elements for the next 5,000 years,” he says.

Only in recent decades have temperatures warmed enough to free trees from their ice cellars. The current tree line is “likely to shift upward as temperatures rise in the coming decades,” Whitlock said.

“This discovery was made possible thanks to anthropogenic climate change. Rising temperatures are exposing areas that have been buried under ice for thousands of years,” she says. “While discoveries like this are scientifically interesting, they are also a sad reminder of how vulnerable alpine ecosystems are to climate change.”

“This study is a very elegant and careful use of a rare 'time capsule' that tells us not only about these mountain forests 6,000 years ago, but also about the climatic conditions that allowed them to exist.” '' he says. Kevin Antukaitis at the University of Arizona.

These trees are not the first such finds that researchers have unearthed from Rocky Mountain ice. Previous research had found “fragments of wooden shafts used for arrows and darts,” Whitlock said. One of the shafts has been radiocarbon dated to be more than 10,000 years old, “which tells us that people have been hunting in high-altitude environments for thousands of years,” she says.

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Source: www.newscientist.com

Nations are falsely achieving net zero by excessively depending on forests

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Russia’s plan to reach net zero by 2060 relies on existing forests to absorb continued carbon emissions

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Countries are taking shortcuts to net-zero emissions by including forests and other “passive” carbon sinks in their climate plans, a tactic that thwarts global efforts to halt climate change. leading researchers have warned.

Relying on natural carbon sinks to absorb continued carbon emissions from human activities will keep the world warmer. This comes from the researchers who first developed the science behind net zero emissions and today launched a highly unusual intervention accusing nations and companies of abusing the concept.

“This document calls on people to be clear about what net zero really means.” Miles Allen The Oxford University professor said this at a press conference on November 14th.

Natural sinks such as forests and peat bogs play an important role in the Earth’s natural carbon cycle by absorbing some of the carbon from the atmosphere. However, we cannot rely on existing sinks to offset ongoing greenhouse gas emissions.

If used in this way, global atmospheric carbon dioxide concentrations would remain stable even when we reach “net zero,” and warming would continue for centuries due to the way the oceans absorb heat. Allen warned. “Even if we think we’re on the path to 1.5C, we could end up with temperatures rising well above 2C,” he says. “This ambiguity could effectively destroy the goals of the Paris Agreement.”

To halt global temperature rise, we need to reduce emissions to net zero, without relying on passive absorption by land and oceans. This allows existing natural sinks to continue absorbing excess CO2, reducing the concentration of the gas in the atmosphere and offsetting ongoing warming from the deep ocean.

However, many countries already count passive land sinks such as forests as greenhouse gas removals in their national carbon accounts. In some countries, such as Bhutan, Gabon, and Suriname, Already declared net zeroThanks to the existing vast forests.

Some companies are setting long-term net-zero targets based on this approach. For example Russia Pledging to achieve net-zero emissions by 2060but this plan relies heavily on using existing forests to absorb ongoing carbon emissions.

“Maybe some countries will use this in a deliberately naughty way.” glenn peters He is from the CICERO International Climate Research Center in Oslo, Norway, and spoke at a press conference. “This problem will be even more problematic in countries where forest area is a large proportion of total land area.”

The researchers fear this problem will become more serious as carbon markets develop and pressure on countries to decarbonize increases. “As the value of carbon increases, there will be more pressure to define anything that can be removed as a negative emission, potentially to be able to sell it in the carbon offset market,” Allen said.

Countries and companies with net-zero targets will need to modify their approach to exclude passive carbon sequestration from their accounts, the researchers say.

Natural sinks count as carbon removal when they are added to existing ones, for example when new forests are planted or peat bogs are rewetted. However, this type of natural carbon sink is vulnerable to climate impacts such as wildfires, drought, and the spread of invasive species, and is unreliable for long-term sequestration.

This has not stopped countries from relying heavily on these natural sinks in their net-zero strategies. one 2022 survey It turns out that a number of countries, including the United States, France, Cambodia and Costa Rica, plan to rely on forest carbon and other naturally occurring removals to offset ongoing emissions. “Many national strategies ‘bet’ on increasing carbon sinks in forests and soils as a means of achieving long-term goals,” the study authors wrote.

Allen stressed that natural carbon sinks must be conserved but not relied on to balance ongoing emissions. Instead, he urges countries to aim for “geological net zero,” where all ongoing carbon emissions are balanced by long-term carbon sequestration in underground storage.

“Countries need to recognize the need for geological net zero,” he said. “That means if we are producing carbon dioxide from burning fossil fuels by mid-century, we need to have a plan to put that carbon dioxide back into the ground.”

“Geological net zero seems like a sensible global goal for countries to aspire to,” he says. harry smith At the University of East Anglia, UK. “This will help clarify many of the ambiguities that plague the current way countries consider land travel.”

But he warns that it could have a knock-on effect on climate ambitions. “What does the new politics of geological net zero look like? If geological net zero drives the goals of governments’ climate strategies, what does this mean for governments’ climate change ambitions?” Will it have an impact?”

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Source: www.newscientist.com

Beautiful photography captures the beauty of mangrove forests

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These graceful and serene photographs pay tribute to an important yet declining ecosystem: mangrove forests. These photos are some of this year's top entries. Mangrove Photography AwardThe work showcases the beauty, diversity and fragility of mangroves, which grow in salty coastal waters in stark contrast to most other trees.

The dramatic photo above captures the middle of a mangrove forest along the vibrant blue coast of the United Arab Emirates. Taken by photographer Amar Alsayed Ahmed, the image won the competition's Mangroves and Landscapes category.

The winner in this category was another photo by Alsayed Ahmed, showing a gracefully meandering river (above). The golden mangroves dotted along the river accentuate the lush greenery it brings to the region.

Unfortunately, this is not the case for mangrove forests, which are proliferating around the world. Despite being hotspots of biodiversity and important carbon stores that help offset climate change, mangroves are under threat from factors such as logging, aquaculture and water pollution, which in turn threaten the wildlife and people that depend on them.

These include species like lemon sharks, and Gillian Morris' entry (pictured above) features a young pair photographed in the Bahamas that was highly commended in the Mangrove and Underwater category. Lemon sharks spend the first few years of their lives in mangrove “nurseries” and are one of the many marine creatures that live there.

In Abu Dhabi, United Arab Emirates, an ambitious project is underway to plant and restore coastal mangroves. Abu Dhabi Mangrove Initiative (ADMI) It is part of a nationwide effort to plant 100 million mangrove trees across the UAE by 2030. In 2023 alone, specially modified drones were used to distribute more than six million seeds.

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Source: www.newscientist.com