Amazon mangroves store twice as much carbon per acre as region’s famous rainforest

• Mangroves represent 0.6 percent of all the world’s tropical forests but their deforestation accounts for as much as 12 percent of greenhouse gas emissions that come from all tropical deforestation.

Oregon State University  Read full ScienceDaily article here

Scientists have determined [from a long term stud] for the first time that Amazon’s waterlogged coastal mangrove forests, which are being clear cut for cattle pastures and shrimp ponds, store significantly more carbon per acre than the region’s famous rainforest.

The Brazilian mangrove forest fringes the entirety of the Atlantic Coast at the mouth of the Amazon, the largest river in the world with the largest mangrove forest. Although preservation of the Amazon rainforest has been the subject of intense awareness efforts over the last few decades, less attention has been paid to the Amazon mangroves….

….Mangroves are a group of trees and shrubs that live in tropical coastal intertidal zones. There are about 80 different species of mangrove trees. All of these trees grow in areas of waterlogged soils, where slow-moving waters allow fine sediments to accumulate. In these environments, mangroves sequester significant quantities of carbon that is stored for centuries….

The Brazilian mangrove forest fringes the entirety of the Atlantic Coast at the mouth of the Amazon River.
Credit: Photo courtesy Danillo Jefferson Romero, University of Sau Paulo

J. Boone Kauffman, Angelo F. Bernardino, Tiago O. Ferreira, Leila R. Giovannoni, Luiz Eduardo de O. Gomes, Danilo Jefferson Romero, Laís Coutinho Zayas Jimenez, Francisco Ruiz. Carbon stocks of mangroves and salt marshes of the Amazon region, Brazil. Biology Letters, 2018; 14 (9): 20180208 DOI: 10.1098/rsbl.2018.0208

National parks bear the brunt of climate change

• Temperatures in national parks are increasing at twice the rate of the US as a whole; most exposed national parks could soar by as much as 9 degrees Celsius or 16 degrees Fahrenheit by 2100.
• Without action to limit greenhouse gas emissions, many small mammals and plants may be brought to the brink of extinction by the end of the century, the study shows.

University of California – Berkeley Read full ScienceDaily article here

Human-caused climate change has exposed US national parks to conditions hotter and drier than the rest of the nation, says a new study quantifying for the first time the magnitude of climate change on all 417 parks in the system. Without action to limit greenhouse gas emissions, many small mammals and plants may be brought to the brink of extinction by the end of the century, the study shows.

….At the current rate of emissions, the team projects that temperatures in the most exposed national parks could soar by as much as 9 degrees Celsius or 16 degrees Fahrenheit by 2100. This rate of change is faster than many small mammals and plants can migrate or “disperse” to more hospitable climates…..

National Park Service

Patrick Gonzalez, Fuyao Wang, Michael Notaro, Daniel J Vimont, John W Williams. Disproportionate magnitude of climate change in United States national parks. Environmental Research Letters, 2018; 13 (10): 104001 DOI: 10.1088/1748-9326/aade09

Researchers find precipitation thresholds regulate carbon exchange–primary control switches from production to respiration at an annual threshold 30-35 inches

• The primary control switches from production to respiration at an annual precipitation threshold between 30 and 35 inches in the contiguous United States.
• The carbon balance of ecosystems in the dry West is very sensitive to photosynthesis. In contrast, the carbon balance of more mesic Eastern U.S. ecosystems is more sensitive to carbon lost through respiration.
• Climate models are far too sensitive to photosynthesis and not sensitive enough to respiration, suggesting the Earth’s ecosystems may lose more carbon to the atmosphere in the future as surface temperatures continue to warm

The University of Montana Read full ScienceDaily article here

One of the major sources of uncertainty about the future climate is whether ecosystems will continue to take up carbon dioxide or release it to the atmosphere. Researchers confronted this problem using atmospheric measurements and satellite observations to test model simulation…

….Ecosystems either soak up carbon through photosynthesis — a negative feedback that could reduce future warming — or release it through respiration — a positive feedback that could enhance future warming. Understanding how climate change might impact ecosystem photosynthesis and respiration is critical for predicting future carbon dynamics.

…Climate models do not reflect this precipitation threshold. Liu and his co-authors determined that these models are far too sensitive to photosynthesis and not sensitive enough to respiration, suggesting the Earth’s ecosystems may lose more carbon to the atmosphere in the future as surface temperatures continue to warm.

“In different regions, the interannual variation of net carbon uptake is primarily impacted by different processes — respiration or photosynthesis,” Liu said. “To me, the most important part of this study is that the models need improvement on respiration.”

Co-author and UM bioclimatology Associate Professor Ashely Ballantyne adds, “This study suggests we know more about the negative feedback loop and less about the positive one.”

Zhihua Liu, Ashley P. Ballantyne, Benjamin Poulter, William R. L. Anderegg, Wei Li, Ana Bastos, Philippe Ciais. Precipitation thresholds regulate net carbon exchange at the continental scale. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-05948-1

Common weed killer linked to bee deaths

• New research shows that honey bees exposed to glyphosate, the active ingredient in Roundup, lose some of the beneficial bacteria in their guts and are more susceptible to infection and death from harmful bacteria, contributing to the decline of honey bees and native bees around the world.

University of Texas at Austin  Read full ScienceDaily article here

Honey bees exposed to glyphosate, the active ingredient in Roundup, lose some of the beneficial bacteria in their guts and are more susceptible to infection and death from harmful bacteria. Scientists believe this is evidence that glyphosate might be contributing to the decline of honey bees and native bees around the world.

Erick V. S. Motta, Kasie Raymann, Nancy A. Moran. Glyphosate perturbs the gut microbiota of honey bees. Proceedings of the National Academy of Sciences, 2018; 201803880 DOI: 10.1073/pnas.1803880115

Land-based bird populations are at risk of local extinction

• “As one of the most biologically degraded areas, Sundaland offers a stark warning to the rest of the world should global rates of land conversion continue unabated. Conservation’s end goal is not islands of biodiversity, marooned in a sea of destruction. More land must be managed in a way that accommodates biodiversity for the long term.”

University College London  Read ScienceDaily article here

A new report finds that land-based bird populations are becoming confined to nature reserves in some parts of the world — raising the risk of global extinction — due to the loss of suitable habitat.

….The study, published today in Conservation Letters, focuses on galliformes — heavy-bodied ground-feeding birds such as pheasants, grouse and quail — as their numbers are well-recorded and they are amongst the most threatened species in some parts of the world.

Scientists found that up to 13 populations (25 per cent of galliform populations in the area) have been extirpated (made locally extinct) in the region and no longer exist outside nature reserves (protected areas). The island of Sumatra has suffered the highest proportion of extirpations among the areas studied, having lost 50 percent of its galliform species in unprotected land.

As a result, certain species are only found in protected areas — raising questions about the ultimate goal of conservation…

Elizabeth H. Boakes Richard A. Fuller Philip J.K. McGowan. The extirpation of species outside protected areas. Conservation Letters, 2018; DOI: 10.1111/conl.12608

Diverse forests are stronger against drought

• Trees that employ a high diversity of traits related to water use suffer less of an impact from drought. The results, which expand on previous work that looked at individual tree species’ resilience based on hydraulic traits, lead to new research directions on forest resilience and inform forest managers working to rebuild forests after logging or wildfire.
• “After we log a forest or a fire comes through,” Anderegg says, “we sometimes think about planting a single species. We should be thinking about the best mixes of multiple species for resilience.”

University of Utah   Read ScienceDaily article here

Researchers report that forests with trees that employ a high diversity of traits related to water use suffer less of an impact from drought. The results, which expand on previous work that looked at individual tree species’ resilience based on hydraulic traits, lead to new research directions on forest resilience and inform forest managers working to rebuild forests after logging or wildfire….

William R. L. Anderegg, Alexandra G. Konings, Anna T. Trugman, Kailiang Yu, David R. Bowling, Robert Gabbitas, Daniel S. Karp, Stephen Pacala, John S. Sperry, Benjamin N. Sulman, Nicole Zenes. Hydraulic diversity of forests regulates ecosystem resilience during drought. Nature, 2018; DOI: 10.1038/s41586-018-0539-7

New Book- Dirt to Soil: One Family’s Journey into Regenerative Agriculture

Soon to be available here.

Summary:

Gabe Brown didn’t set out to change the world when he first started working alongside his father-in-law on the family farm in North Dakota. But as a series of weather-related crop disasters put Brown and his wife, Shelly, in desperate financial straits, they started making bold changes to their farm. Brown―in an effort to simply survive―began experimenting with new practices he’d learned about from reading and talking with innovative researchers and ranchers. As he and his family struggled to keep the farm viable, they found themselves on an amazing journey into a new type of farming: regenerative agriculture.

Brown dropped the use of most of the herbicides, insecticides, and synthetic fertilizers that are a standard part of conventional agriculture. He switched to no-till planting, started planting diverse cover crops mixes, and changed his grazing practices. In so doing Brown transformed a degraded farm ecosystem into one full of life―starting with the soil and working his way up, one plant and one animal at a time.

In Dirt to Soil Gabe Brown tells the story of that amazing journey and offers a wealth of innovative solutions to our most pressing and complex contemporary agricultural challenge―restoring the soil. The Brown’s Ranch model, developed over twenty years of experimentation and refinement, focuses on regenerating resources by continuously enhancing the living biology in the soil. Using regenerative agricultural principles, Brown’s Ranch has grown several inches of new topsoil in only twenty years! The 5,000-acre ranch profitably produces a wide variety of cash crops and cover crops as well as grass-finished beef and lamb, pastured laying hens, broilers, and pastured pork, all marketed directly to consumers.

The key is how we think, Brown says. In the industrial agricultural model, all thoughts are focused on killing things. But that mindset was also killing diversity, soil, and profit, Brown realized. Now he channels his creative thinking toward how he can get more life on the land―more plants, animals, and beneficial insects. “The greatest roadblock to solving a problem,” Brown says, “is the human mind.”

Big increase in economic costs if cuts in greenhouse gas emissions are delayed

• Stronger efforts to cut greenhouse gas emissions should be undertaken to avoid global warming of more than 1.5 degrees Celsius — without relying on potentially more expensive or risky technologies to remove carbon dioxide from the atmosphere or reduce the amount of sunlight reaching Earth’s surface.
• The remaining carbon budget consistent with 1.5ºC is very small and the global economy would need to be decarbonized at an unprecedented scale to stay within it, likely entailing larger costs.

University of East Anglia Read full ScienceDaily article here

A comprehensive new analysis involving researchers from UEA warns that the target of limiting global warming to 1.5ºC could soon become too economically expensive to justify, despite the benefits it could provide.

….There is evidence to suggest that limiting warming to 1.5ºC reduces the risk of crossing climate tipping points, such as melting of the Greenland and Antarctic ice sheets, but the reduction in risk cannot presently be quantified…

….”Our review of recent studies shows the significant projected benefits of limiting global warming to 1.5ºC rather than 2ºC above pre-industrial levels for both human and natural systems. These benefits include preservation of Arctic sea ice, reduced biodiversity loss, and reduced damage to coral reefs.”

Simon Dietz, Alex Bowen, Baran Doda, Ajay Gambhir, Rachel Warren. The Economics of 1.5°C Climate Change. Annual Review of Environment and Resources, 2018; 43 (1) DOI: 10.1146/annurev-environ-102017-025817

Improving ‘silvopastures’ for bird conservation

• The results show that silvopasture habitat could be improved by managing for higher tree species diversity and greater structural complexity, but that preserving natural forest fragments in agricultural landscapes is also crucial.
• “Protected areas alone will be insufficient to conserve biodiversity at global scales. Instead, we must find ways to safeguard species and ecosystems while also sustaining human communities and livelihoods that depend upon local resources,”

American Ornithological Society Publications Office  Read ScienceDaily article here

The adoption of ‘silvopastures’ — incorporating trees into pastureland — can provide habitat for forest bird species and improve connectivity in landscapes fragmented by agriculture. But how do silvopastures measure up to natural forest habitat? New research shows that birds in silvopasture forage less efficiently than those in forest fragments but offers suggestions for how silvopasture habitat could be improved….

Bryan C. Tarbox, Scott K. Robinson, Bette Loiselle, S. Luke Flory. Foraging ecology and flocking behavior of insectivorous forest birds inform management of Andean silvopastures for conservation. The Condor, 2018; 120 (4): 787 DOI: 10.1650/CONDOR-18-1.1

Paris climate targets could be exceeded sooner than expected–due to changes in permafrost

International Institute for Applied Systems Analysis  Read ScienceDaily article here

A new study has for the first time comprehensively accounted for permafrost carbon release when estimating emission budgets for climate targets. The results show that the world might be closer to exceeding the budget for the long-term target of the Paris climate agreement than previously thought.

….The upper layer of permafrost (the active layer) periodically thaws in the summer, but in recent years, the active layer of permafrost has gradually been expanding due to increasing temperatures. This means that more permafrost is thawing and thus releasing the previously trapped carbon into the atmosphere.

….This is the first time that such a tipping process is adequately accounted for in emission budgets, and according to the researchers, doing so shows that the world is closer to exceeding the budget for the long-term target of the Paris Agreement than previously thought.

T. Gasser, M. Kechiar, P. Ciais, E. J. Burke, T. Kleinen, D. Zhu, Y. Huang, A. Ekici, M. Obersteiner. Path-dependent reductions in CO2 emission budgets caused by permafrost carbon release. Nature Geoscience, 2018; DOI: 10.1038/s41561-018-0227-0