forest

Forest Regrowth In The Amazon | Earth Wise

January 20, 2020 By EarthWise Leave a Comment

The Amazon is the largest tropical rainforest in the world. It covers an area approximately equal in size to the lower 48 states, and is home to an estimated 10% of the world’s biodiversity and 15% of its freshwater. These so-called “lungs of the planet” provide many important global ecological services, including carbon storage, and regulating air quality and climate.

Deforestation in the Amazon exploded in the 1970s and remains one of its biggest threats today. Since the 1970s, more than 20% of the Amazon rainforest has been cleared. Cattle ranching, soy and palm plantations, logging, and climate change are some of the biggest drivers of deforestation.

Now, according to a new study recently published in the journal Ecology, the regrowth of Amazonian forests following deforestation may happen more slowly than previously thought. These findings could have significant impacts on climate change predictions as the ability of forest regrowth in the Amazon – so-called secondary forests – may have been overestimated. The research, which was conducted in Bragança, Brazil and includes two decades of forest monitoring, reveals that climate change and the wider loss of forests could be hampering regrowth.

After 60 years of regrowth, the research team found that secondary forests only held 40% of the carbon when compared with forests undisturbed by humans. Secondary forests also take less carbon from the atmosphere during periods of drought, and climate change is increasing the number of drought-years in the Amazon. (During their 20 years of monitoring, the researchers also found biodiversity levels in secondary forests were only 56% of those seen in undisturbed forests).

More long-term studies are needed to better understand the impacts of reforestation efforts.

**********

Web Links

Amazon forest regrowth much slower than previously thought

Photo, posted September 6, 2009, courtesy of Nao Lizuka via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Trees And The Future Of Cities

April 16, 2019 By EarthWise Leave a Comment

The shade of a single tree is a welcome source of relief on a hot summer day. But even a relatively small patch of woods can have a profound cooling effect. A new study at the University of Wisconsin-Madison looks at the role trees play in keeping towns and cities cool.

According to the study, the right amount of tree cover can lower daytime temperatures in the summer by as much as 10 degrees. The effects are noticeable from neighborhood to neighborhood and even on a block-by-block basis.

Cities are well-known to be hot spots due to the urban heat islanding effect. Using trees to keep temperatures more comfortable in cities can make a big difference for the people who live and work there.

The man-made structures of cities – roads, sidewalks, and buildings – absorb heat from the sun during the day and slowly release it at night. Trees, on the other hand, not only shade those structures from the sun, but they also transpire -or release water in the air through their leaves – which helps to cool things down.

According to the study, to get maximum cooling benefits, tree canopies must exceed forty percent, meaning that city blocks need to be nearly halfway covered by tree branches and leaves. To get the biggest bang for the buck, cities should start planting more trees in areas that are already near the forty percent threshold. But

trees can’t just be in parks. They need to be in places where people are active.

If we want the places where we live to be more comfortable and resilient in a warming world, we need to plant more trees.

**********

Web Links

Study suggests trees are crucial to the future of our cities

Photo, posted May 26, 2012, courtesy of Mislav Marohnic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Indonesian Deforestation

February 28, 2019 By EarthWise Leave a Comment

Deforestation is defined as the intentional destruction of trees and other vegetation without reforesting or allowing the forest to regenerate itself.

In Indonesia, industrial agriculture, primarily for the production of palm oil, is a major driver of deforestation. But, according to researchers at Duke University, its impact has diminished proportionately in recent years as other natural and human causes have emerged. Their peer-reviewed findings were recently published in the journal Environmental Research Letters.

According to the study’s lead author, large-scale plantations were responsible for more than half of Indonesia’s deforestation in the late 2000s, peaking between 2008-2010 when an average of 1.5 million acres of forest was lost annually. The expansion of the massive plantations was responsible for 57% of the forest loss. Between 2014-2016, an average of more than 2 million acres of forest was lost annually, but plantation expansion only accounted for 25% of this figure. While the overall rate of deforestation continued to grow, other factors were responsible for most of it.

Conversions of forests to grasslands rose sharply in 2015 and 2016 when El Nino caused severe droughts and forest fires. Small-scale farming, often overshadowed by industrial agriculture, was also found to play a bigger role, accounting for 25% of all forest loss.

Indonesia has experienced some of the highest rates of deforestation. Its forests absorb and store vast amounts of climate-warming carbon dioxide, help prevent erosion and flooding, and provide habitat to thousands of species. Understanding the varied causes of Indonesian deforestation should help conservationists and policymakers better address the problem.

************

Web Links

Palm oil not the only driver of forest loss in Indonesia

Photo, posted March 26, 2018, courtesy of Achmad Rabin Taim via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cloning Ancient Redwoods

January 30, 2019 By EarthWise Leave a Comment

During the 19th and 20th centuries, many of the world’s largest and oldest tress were cut down for their lumber. Some of these coast redwoods were 3,000 years old and measured 35 feet in diameter.

Today, giant stumps of these ancient redwoods dot the landscape from Oregon to northern California and are a remnant of the old-growth forest that once stretched across much of the Pacific Northwest.

An organization called the Archangel Ancient Tree Archive is dedicated to reestablishing ancient redwood forests to help combat climate change. Coastal redwoods are not only huge but can grow an average of 10 feet a year. One of these enormous trees can sequester 250 tons of carbon dioxide over its lifetime, more than 200 times the amount for an average tree.

While many experts thought that the giant stumps were lifeless, arborists at Archangel collected DNA from the stumps of five giant coast redwoods, all larger than the largest tree living today. They then used this genetic material to grow dozens of saplings, which are clones of the ancient trees, in a process that takes about two-and-a-half years.

To date, the Archangel Ancient Tree Archive has planted nearly 100 of these saplings in the Eden Project garden in Cornwall, England, a couple of hundred in Oregon, and most recently, has planted 75 in the Presidio National Park in San Francisco.

According to arborists at the nonprofit organization, these saplings have extraordinary potential to purify our air, water, and soil for generations to come. Their hopes are that the new San Francisco ‘super grove’ will be allowed to grow unmolested by manmade or natural disasters and thus propagate forever.

**********

Web Links

Arborists Have Cloned Ancient Redwoods From Their Massive Stumps

Photo, posted April 8, 2013, courtesy of Michael Balint via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Your Children’s Yellowstone

January 25, 2019 By EarthWise Leave a Comment

Yellowstone National Park was the first national park in the US and according to some sources, the first in the world. It is the home of charismatic megafauna and stunning geysers that attract over four million visitors a year. It is the only place in the United States where bison and wolves can be seen in great numbers. And it is changing.

Over the next few decades of climate change, Yellowstone will quite likely see increased fire, less forest, expanding grasslands, shallower, warmer waterways, and more invasive plants. All these things will alter how and how many animals move through the landscape. Ecosystems are always changing, but climate change is transforming habitats so quickly that many plants and animals may not be able to make the transition at all.

Since 1948, the average annual temperature in the Greater Yellowstone ecosystem has gone up by 2 degrees Fahrenheit. On balance, winter is 10 days shorter and less cold. The Northern Rockies snowpack has fallen to its lowest level in eight centuries. Summers in the park are warmer, drier, and increasingly prone to fire.

Non-nutritious invasive plants like cheatgrass and desert madwort have replaced nutritious native plants. When plants like these take over, they suck moisture out of the ground early so that bison and elk cannot be sustained throughout the summer.

The behavior of elk and other animals is already changing, with many staying outside the park to nibble lawns and alfalfa fields. In turn, wolves go where the elk go. Forests and waterways are changing as well.

The rapid changes going on at Yellowstone mean that the park that our children and grandchildren will visit in the future is likely to be a very different one from the Yellowstone we remember.

**********

Web Links

In Yellowstone National Park, warming has brought rapid changes.

Photo, posted September 7, 2016, courtesy of Mike Yang via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Can We Remove Enough CO2 From The Air?

January 9, 2019 By EarthWise Leave a Comment

As atmospheric carbon dioxide levels continue to set new records and the effects of climate change grow stronger, humanity has continued to procrastinate on reducing emissions. As a result, it is increasingly clear that any strategy to avoid runaway climate change will have to involve the use of “negative emissions”- techniques or technologies that actually remove CO2 from the air.

There are both low-tech and high-tech methods for removing carbon dioxide from the atmosphere and both are likely to be needed.

On the low-tech side, afforestation (planting trees where there were none before), reforestation, changes in forest management, rebuilding the carbon backbone in agricultural soils, and the use of energy from waste biomass are all ways to take carbon out of the atmosphere.

On the high-tech side, direct air capture technologies that take CO2 out of the air and store it in the ground are making rapid progress. Right now, they are still very expensive,but that is changing. There is an analogy to wind and solar technology. Not very long ago, both of those technologies were quite expensive but now their costs have plummeted to the point where they are often the cheapest way to make electricity. With sufficient development effort and deployment, direct air capture technology could become quite affordable.

Some people advocate geoengineering as a solution for climate change. While removing carbon dioxide amounts to tackling the root cause of the warming climate,geoengineering would address the problem by changing the climate again in some other way. It is at best an extremely dangerous approach.

Removing CO2 using a combination of natural and man-made techniques is an important part of mitigating the effects of climate change.

**********

Web Links

Climate Solutions: Is It Feasible to Remove Enough CO2 from the Air?

Photo courtesy of Climeworks.

Earth Wise is a production of WAMC Northeast Public Radio.

Bring The Wild Back Into Farmlands

December 4, 2018 By EarthWise Leave a Comment

A recent study published in Science looks at the effects of maintaining at least a little bit of the wild on working lands including farmland, rangeland and forests. The study concludes that doing so may be a key to preserving biodiversity in the face of climate change.

Losing Forests Is Felt Far Away

July 6, 2018 By EarthWise 2 Comments

Large areas of forests in our country are vulnerable to drought, fires and disease. When forests are heavily damaged, there are well-known local impacts: drier soils, stronger winds, increased erosion, loss of shade and loss of habitat.

Indonesian Deforestation Continues

May 3, 2018 By EarthWise Leave a Comment

Worldwide, deforestation and land disturbance are responsible for about a quarter of all greenhouse gas emissions. The largest contributor to this problem is Indonesia and getting control of its emissions is a crucial part of meeting global carbon reduction targets.

Elephant Losses Imperil Forests

April 20, 2018 By EarthWise Leave a Comment

Poaching and habitat loss have reduced Central African elephant populations by 63% since 2001. These losses not only pose dire consequences for the elephants themselves but also for the forests in which they live.

Tree-Planting Drones

March 16, 2018 By EarthWise Leave a Comment

One of the major causes of the increasing carbon dioxide levels in the atmosphere is deforestation. We chop down about 15 billion trees each year. Over time, our activities have reduced the number of trees on earth by about 50%. We do plant trees – these days, about 9 billion a year. It is a substantial number, but still leaves a net loss of 6 billion trees annually.

[Read more…] about Tree-Planting Drones

Saving The Siberian Tiger

March 13, 2018 By EarthWise Leave a Comment

The northeastern part of China, wedged between North Korea to the south and Russia to the northeast, is home to two highly endangered big cats: the Siberian tiger and the Amur leopard. Siberian tigers, which can weigh over 600 pounds and grow to more than 10 feet in length, now number only about 500 in the wild, mostly in Russia. Amur leopards, weighing more than 100 pounds and growing to more than four feet in length, number only about 80 in the wild. While both species are right on the edge of extinction, both are slowly rebounding.

The Restoration Economy

March 2, 2018 By EarthWise Leave a Comment

Deforestation is one of the largest contributors to climate change. Forests cover about 30% of the world’s land area and are a crucial sink for carbon dioxide. Over time, we have been steadily reducing the amount of forest in the world to obtain wood and timber, open up farmland, build towns and cities, produce paper, make palm oil, and mine for minerals.

A Carbon Loophole

February 12, 2018 By EarthWise Leave a Comment

Many power plants in Europe and elsewhere are replacing coal with wood. For example, the Drax Power Station in Britain was its largest coal-burning plant and is now using wood pellets shipped from the southern U.S. in its boilers. According to the carbon accounting rules at the EU and elsewhere, the process is considered to be “carbon neutral.” But is it?

The idea is that new trees are being planted in the forests where the trees are cut to be burned in power plants. So, there is carbon neutrality. In principle.

European countries have embarked on a massive effort to switch to generating power from renewable energy. While there has indeed been major growth in wind and solar power in the 28 countries of the European Union, much of the new “green” power has come from burning wood in converted coal power stations.

A group of 200 scientists wrote to the EU last September insisting that bioenergy from forest biomass is not carbon neutral and that there must be tighter rules to protect forests and their carbon. Wood burning has become a loophole in controlling carbon emissions.

There are problems with the claims of carbon neutrality. There is no way to know whether enough new trees are actually being planted to replace those being burned. And then there is the time lag for tree replacement. Trees don’t grow overnight. There are also the carbon emissions associated with harvesting, processing and transporting wood.

There are most certainly ways in which burning biomass can be carbon neutral and can represent real progress over the use of fossil fuels. But caution must be taken to avoid exploiting loopholes in current climate rules that might actually result in increased carbon emissions.

**********