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Rewilding The American West | Earth Wise

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Oregon State University scientists have proposed a series of management changes for western federal lands aimed at re-establishing ecosystems there.  Their proposal would result in more gray wolves and beavers in nearly 200,000 square miles of federal lands in 11 states.

In each of those states, the researchers identified areas containing prime wolf habitat.  Gray wolves were hunted to near extinction in the West but have been gradually reintroduced in some areas starting in the 1990s.  Wolf restoration offers significant ecological benefits by helping to naturally control the population of grazing animals such as elk.  This in turn facilitates the regrowth of vegetation species such as aspen, which ultimately supports diverse plant and animal communities.

Beaver populations, which used to be robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many areas.  By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and settlement retention, maintain water flows during droughts, and increase carbon sequestration.

According to the researchers, the biggest threat to these western lands is livestock grazing, which has degraded ecosystems to a great extent.  They recommend the removal of grazing on about 30% of the federal lands being used for that purpose and instead would have rewilding efforts go on. 

The American West is going through a period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires, and loss of biodiversity.  Rewilding is a way to reestablish long-standing ecosystems.

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More wolves, beavers needed as part of improving western United States habitats, scientists say

Photo, posted October 1, 2020, courtesy of Tina DaPuglet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Agriculture’s Carbon Footprint | Earth Wise

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Agriculture is responsible for about 10% of greenhouse gas emissions.  Those emissions come from livestock such as cows, the disturbance of agricultural soils, and activities like rice production.

Recent research from Texas A&M University presents sustainable solutions for grazing agriculture.  According to the research, published in the Journal of Soil and Water Conservation, ruminant animals like cattle contribute to the maintenance of healthy soils and grasslands, and proper grazing management can reduce the industry’s carbon emissions and overall footprint.

Grassland ecosystems co-evolved with herbivores over thousands of years.  These complex, dynamic ecosystems include grasses, soil biota, grazing animals, and predators.  The ecosystems degrade in the absence of periodic grazing.

The research contends that ruminant livestock are an important tool for achieving sustainable agriculture with appropriate grazing management.  With such management, grazing cattle on permanent perennial grasslands helps develop soil biology to improve soil carbon, rainfall infiltration, and soil fertility.

Permanent cover of forage plants is highly effective in reducing soil erosion and increasing soil infiltration.  Ruminants consuming grazed forages under appropriate management results in considerably more carbon sequestration than carbon emissions.

This overall approach is known as regenerative agriculture and is built around the ideas of practices that restore soil health and ecosystem function to support healthy agroecosystems. 

These ideas constitute alternatives to ones that call for the reduction or elimination of cattle and livestock agricultural production.  The future of agriculture needs to consider the full impacts of the entire food production chain and its environmental impacts.

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Grazing Cattle Can Reduce Agriculture’s Carbon Footprint

Photo, posted April 27, 2010, courtesy of Beverly Moseley/USDA NRCS Texas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Nature Is Valuable | Earth Wise

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A study by the University of Vermont, the University of Cambridge, and several other institutions compared the value of protecting nature at particular locations with that of exploiting it.   The study concluded that the economic benefits of conserving or restoring natural sites outweigh the profit potential of converting them for intensive human use.

The study analyzed dozens of sites across the globe – from Kenya to Fiji and China to the UK across six continents.  It was published in the journal Nature Sustainability.

The analysis utilized a methodology devised ten years ago called TESSA (the Toolkit for Ecosystem Service Site-based Assessment) which enables users to measure, and in many cases, assign monetary values to services provided by sites – clean water, nature-based recreation, crop pollination, and so on.  This is then compared with the economic benefits that can be derived by converting the site for farming, logging, or other human uses.

A major economic benefit of natural sites comes from their ability to sequester carbon and thereby help regulate the quantity of greenhouse gases in the atmosphere.  If one assigns a value to global society of $31 a ton of carbon removed, over 70% of the sites surveyed had a greater value to society when kept natural rather than being converted.  Many scientists actually consider this carbon price to be conservative.  Nevertheless, if carbon is assigned the paltry cost of $5 a ton, 60% of the sites are still more valuable in their natural state.

Beyond these economic calculations, there is the pressing issue that current rates of habitat conversion are driving a species extinction crisis unprecedented in human history.  But even if one is only interested in dollars and cents, conserving and restoring nature is now very often the best bet for human prosperity.

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Economic Benefits of Protecting Nature Exceed Value of Exploiting it, Global Study Finds

Photo, posted June 7, 2017, courtesy of Mouli Choudari via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

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The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world.  In Mexico, the pads are known as nopales and are used in a variety of dishes.  The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops.  Cactus pear can be used for both human consumption and livestock feed.  As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear.  The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid.  There is enormous potential for planting cactus for carbon sequestration.  If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Carbon Capture Technique | Earth Wise

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Carbon dioxide emissions by electricity generating plants, fossil-fuel burning vehicles, and industry produce about 2/3 of the greenhouse gases driving climate change.  Without decreasing these emissions, the earth will continue to get warmer, sea levels will continue to rise, and the world will face more droughts, floods, wildfires, famine and conflict.

Electrification of vehicles and reliance upon renewable energy sources will ultimately drastically reduce the use of fossil fuels and the resultant emissions, but that transition may take too long to reverse the direction of climate change.  In the meantime, there is a great need to find effective and efficient ways to capture emissions from fossil fuel plants. 

Recent research at the University of California, Berkeley, Lawrence Berkeley National Laboratory, and ExxonMobil has developed a new technique for carbon capture.  The technique makes use of metal-organic framework (or MOF) technology.  An MOF, modified with nitrogen-containing amine molecules, captures CO2 and then low-temperature steam is used to flush out the CO2 either to be used or sequestered underground.

Experiments demonstrated the technique to have a six-times greater capacity for removing CO2 from the flue gas of a refinery than current amine-based technology.  It selectively removed 90% of the emitted CO2. 

There is a relatively limited market for captured CO2, so power plants using the capture technology would likely pump the CO2 into the ground, or otherwise sequester it.  The cost of doing this sort of emission scrubbing would have to be facilitated by government policies, such as carbon trading or a carbon tax, which would provide the necessary economic incentive for doing carbon capture and sequestration.

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New technique to capture CO2 could reduce power plant greenhouse gases

Photo courtesy of UC Berkeley.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree-Planting Is Not Necessarily A Good Thing | Earth Wise

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There is no question that forests have a major role in efforts to combat climate change as well as to slow biodiversity loss.   As a result, tree-planting on a massive scale has gained traction as a strategy and there have been major commitments made to plant billions of trees around the world.

A new study at Stanford University has rigorously analyzed the potential effects of these efforts and has found some significant problems.  For example, the Bonn Challenge, which seeks to restore an area of forest more than eight times the size of California over the next 10 years, has 80% of its commitments in the form of  planting monoculture tree plantations or a limited mix of trees that produce fruit and rubber, rather than restoring natural forests.   The problem is that plantations have significantly less potential for carbon sequestration, habitat creation, and erosion control than natural forests.  The potential benefits of the planting dwindle further if planted trees replace natural flora – forests, grasslands, or savannahs – which are ecosystems that have evolved to support local biodiversity.

The study looked at previous policies that created subsidies for planting trees.  Chile’s Decree Law, in effect from 1974 to 2012, has served as a model for similar policies in a number of countries.  Those subsidies further reduced native forest cover by encouraging the establishment of plantations in places where forests might have naturally regenerated.  The subsidies expanded the area covered by trees, but decreased the area of native forests.

The study recommends that nations should design and enforce their forest subsidy policies to avoid undesirable ecological impacts and actually promote the recovery of carbon- and biodiversity-rich ecosystems.

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Poorly designed tree-planting campaigns could do more harm than good, according to Stanford researcher and others

Photo, posted April 28, 2016, courtesy of the U.S. Department of State via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Family Forests And Climate Change | Earth Wise

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Climate experts consider sequestration and storage of carbon in trees to be among the most affordable and scalable natural climate solutions.  If implemented globally, trees could provide a third of the near-term climate change mitigation needed to meet the terms of the Paris Agreement.

Small family-owned forests make up 38% of U.S. forests, a total area 1.5 times the size of Texas and more than any other ownership type.  Most small landowners want to do right by their land, but they rarely have access to the expertise or resources needed to optimize their forests for carbon sequestration.

This spring, the Nature Conservancy, the American Forest Foundation, and the Vermont Land Trust announced two new programs, funded in part by a $10 million grant by Amazon, that will provide funds to small landowners to grow larger, healthier forests.

Few forests are managed for carbon sequestration.  Practices like fast logging rotations, so-called high-grading that strips out the largest, most valuable trees, and rampant invasive species all compromise the ability of a forest to lock away carbon.  It turns out that most small landowners would like to do better, but they don’t have the expertise or the financial resources to implement sustainable management.

Existing carbon markets are not geared towards small forest owners.  Their payments are tiny and the required contract terms are onerous.  The Family Forest Carbon Program commits landowners for only 10 to 20 years.  Typical landowners won’t get a windfall.  A 100-acre landholding would stand to earn around $24,500 over 20 years. 

If these programs can sign up 20% of U.S. forest landowners, it could offset the emissions from 6 million cars.

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How Small Family Forests Can Help Meet the Climate Challenge

Photo, posted July 14, 2013, courtesy of Joshua Mayer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning CO2 Into Rock

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As the world continues to struggle to find ways to reduce carbon emissions, there is increasing attention being paid to so-called negative emission technologies (NET), which remove and permanently sequester carbon dioxide from the atmosphere.

The University of Victoria in British Columbia has brought together an international team of experts to explore the possibilities of permanently and safely sequestering CO2 as rock beneath the ocean floor.  The Solid Carbon Project seeks to extract carbon dioxide directly from the air and then, using deep-ocean technology powered by offshore solar and wind energy, inject it into sub-seafloor basalt, where it would mineralize into solid carbonate rock.

When CO2 is injected into porous basalt, a type of volcanic rock, it reacts relatively quickly with minerals to form solid carbonate, thereby permanently removing it from the atmosphere.  Because 90% of the planet’s basalt is located beneath the ocean floor, the deep ocean is the place to do this kind of carbon sequestration.

The team includes experts in ocean science, carbon mineralization, renewable energy, engineering design, and oil-and-gas drilling/injection operations. Other experts are focusing on the social and legal implications of the NET technology.

Over the next four years, the Solid Carbon Project will assess the integration of multiple existing technologies that will be needed to successfully develop this kind of carbon storage.  One of these is the direct air capture technology itself, which will need to be adapted to a renewable energy-powered offshore platform.  The best outcome technologies explored by the project will be selected for a real-world demonstration at Ocean Networks Canada’s observatory site, 9,000 feet underwater in the Cascadia Basin, off the coast of British Columbia.

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A rock-solid solution for CO2

Photo courtesy of the University of Victoria.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Vulnerable Shorelines

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Global climate change is having noticeable effects on the environment. For example, glaciers are shrinking.  Plant and animal ranges are shifting and populations decreasing.  And droughts, floods, and wildfires are becoming more frequent and more intense.  According to the Intergovernmental Panel on Climate Change, the evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time. 

Our coastal shorelines, which are already stressed by human activity, pollution, storms, and invasive species, are one of many areas expected to be further threatened by climate change.  Sea level rise and more intense and frequent storms are expected to erode and inundate coastal ecosystems and eliminate wetlands.  Ocean acidification is also projected to disrupt marine environments. 

But according to scientists at the Massachusetts Institute of Technology, seagrasses could play a key role in protecting these vulnerable shorelines from this onslaught.  The MIT research team demonstrated how the ubiquitous marine plants dissipate wave energy and help protect against erosion, which could help mitigate damage from rising seas. 

Using mathematical modelling and experiments, the MIT researchers were able to quantify for the first time how large and dense a continuous meadow of seagrass must be in order to provide adequate damping of waves in a given setting.  They also found that seagrasses offer significant environmental benefits, including preventing beach erosion, protecting seawalls and coastal structures, improving water quality, and sequestering carbon. 

Submerged aquatic vegetation, including seagrasses, provides an ecosystem service exceeding $4 trillion annually.  Hopefully these findings can help provide useful guidance for seagrass restoration efforts.

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Seagrass’ strong potential for curbing erosion

The Effects of Climate Change

Photo, posted October 13, 2010, courtesy of the NOAA Photo Library via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Storing Carbon in the Ocean

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As carbon dioxide levels in the atmosphere continue to rise, it may be that clean energy technologies, electric cars, and other methods of reducing emissions may not be enough.  Carbon sequestration – sucking carbon out of the atmosphere – is seen by many as a crucial part of the solution.

[Read more…] about Storing Carbon in the Ocean

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