Although the devastating consequences of deforestation to plants and animal species living above the ground are well-documented, scientists and others need to better understand how soil communities respond to this deforestation to create interventions that protect biodiversity and the ecosystem. But that information has been lacking.

A team of researchers led by Colorado State University’s André Franco, a research scientist in the Department of Biology, conducted a meta-analysis of nearly 300 studies of soil biodiversity in Amazonian forests and sites in various stages of deforestation and land-use.

The new study, “Amazonian deforestation and soil biodiversity,” is published in the June issue of Conservation Biology and is co-authored by CSU Distinguished Professor Diana Wall, Bruno Sobral, professor in the Department of Microbiology, Immunology and Pathology at CSU, and Artur Silva, professor at the Universidade Federal do Pará in Belém, Brazil.

Overall, the researchers found that the abundance, biomass, richness and diversity of soil fauna and microbes were all reduced following deforestation. Soil fauna or animals that were studied include earthworms, millipedes, dung beetles, nematodes, mites, spiders and scorpions.

Franco, who hails from Brazil, said that this is the first time that all of the available scientific data related to soil biodiversity in Amazonian forests has been synthesized.

The research team also found that the way the land is used after the forest is cleared matters to soil biodiversity. Species of invertebrates such as earthworms, ants and termites — which are described as soil engineers — were more vulnerable to the displacement of forests with pastures than by crops, while microbes showed the opposite pattern.

Franco said the highest biodiversity losses were found on the side of the Amazon with the highest mean annual precipitation and in areas where the soil was very acidic.

“That means these areas should be higher priorities for conservation efforts,” he said.

Scientists also uncovered gaps in existing research.

“Very few studies looked at the impact of disturbances like wildfires and selective logging on these forests,” Franco said. “Yet logging is an official management strategy in the Amazon forest.”

In addition, the team found a lack of data from seven of the nine countries that the Amazon biome covers parts of, including Bolivia, Peru, Ecuador, Venezuela, Guyana, Suriname and French Guiana.

Sobral noted that biodiversity is a hot topic and was elevated recently with the release of a report from the United Nations, which found that nature is declining globally at unprecedented rates. But most of the scientific knowledge in the world about biodiversity relates to birds and mammals, he said.

The team is continuing this research in the Amazon, working with farmers’ associations and two research institutes in Brazil to collect and analyze soil samples with the goal of studying the consequences of this loss of biodiversity.

Zaid Abdo, a bioinformatics expert and associate professor in the Department of Microbiology, Immunology and Pathology, has joined the CSU-based research team.

Sobral said it’s extremely important that the scientists work with local farmers and others who are impacted by the deforestation.

“We’re very focused on making sure the research isn’t disconnected from local communities’ needs and aspirations,” he said. “Our work is guided by what the farmers want to know and how scientific knowledge could shape their future sustainable development.”

“The results from our field experiment unequivocally show that the loss of wetland vegetation increases the rate of erosion on wave-stressed shorelines by 100%,” said Brian R. Silliman, Rachel Carson Professor of Marine Conservation Biology at Duke’s Nicholas School of the Environment.

“These findings are going to make it hard for oil companies whose spills kill marsh grasses or mangroves on the edge of coastal wetlands to say that the loss of plants due to heavy oiling doesn’t have a long-term effect,” he said.

Some industry-sponsored scientists have theorized that the increased erosion of Louisiana marshes following the 2010 Deepwater Horizon spill didn’t stem from the spill itself. They say that Hurricane Katrina, which struck the coast five years earlier, was already causing the marshes to erode faster and that plant loss from the oil spill played a negligible role.

“Our study refutes that claim,” Silliman said. “We’re not saying that soil type and hurricane-driven wave action don’t affect marsh-edge erosion rates too, but our findings clearly show that the loss of plant roots compounds everything else and accelerates erosion even further.”

Silliman and his colleagues published their peer-reviewed paper May 23 in Current Biology.

To test the competing theories, they conducted a three-year field experiment at salt marsh sites in Florida with similar soils, vegetation and wave exposure as marshes that were hit by the Deepwater Horizon spill.

The researchers divided the sites into test plots of different sizes and subjected plots of each size to three different treatments. In some plots, they repeatedly cut the plants’ stems down to the ground but left the roots intact. In other plots, they used herbicide to kill the plants, roots and all. Other plots were left unaltered to serve as controls where researchers could measure the base rate of erosion caused by wave action.

“In plots where we just cut off the stems, no extra erosion over the base rate occurred because the roots were still there to help hold things together. But in plots where we killed the roots too, the amount of land loss increased by 100 percent,” Silliman said.

“The size of the test plot didn’t matter. Wherever we started killing roots, that’s where erosion started happening,” he said.

An analysis of other recent peer-reviewed studies on marsh erosion corroborated the team’s findings and confirmed that the amount of land loss in an affected marsh is directly proportional to the amount of root loss.

“These small-scale experiments confirmed what we found in large-scale observational studies across hundreds of kilometers of heavily oiled marshes in Louisiana following the Deepwater Horizon spill,” Silliman said. “If a disturbance like heavy oiling kills the roots, increased erosion occurs. The more roots killed, the more erosion. And because the eroded area is much lower in elevation and is flooded continuously, the plants can’t grow back. The land has been converted into sea.”

“Coastal wetlands offer protection from storm surges and other extreme weather and climate events,” said David Garrison, a program director in the National Science Foundation’s Division of Ocean Sciences, which funded the research. “This paper is an important step in understanding the resilience of these important ecosystems.”

Various sources have estimated that between 15,000 and 24,000 acres of Gulf Coast salt marshes experienced plant stem oiling above a 90% threshold as a result of the Deepwater Horizon spill. Previous research led by Silliman has shown that 90% is the tipping point at which root death occurs and recovery is no longer possible.

“Given the vital roles coastal salt marshes play in protecting shorelines from erosion and flooding, providing habitat for wildlife and helping clean our water, we need to better understand the thresholds of salt marsh resilience to human disturbances like oil,” Silliman said.

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The multisite international study compares the two methods for identifying women who should be prescribed compression sleeves and gauntlets to reduce lymphatic fluid in the arm and prevent progression to lymphedema.

BIS surveillance reduced rates of progression by approximately 10%, a clinically meaningful improvement. Interim findings from the study were published May 3 in Annals of Surgical Oncology and Ridner presented the analysis during the annual meeting of The American Society of Breast Surgeons in Dallas.

“The bioimpedance device measures lymphatic fluid, and the tape measures everything,” said Ridner, a researcher with Vanderbilt-Ingram Cancer Center. “It takes more lymphatic fluid to make your whole arm volume change than it does to make the device pick up changes. The device is just more sensitive to changes in lymphatic fluid.”

Breast cancer related lymphedema affects between 20% and 30% percent of women due to damage to the lymph glands from surgery, radiation and some medicines, Ridner said. Lymphedema causes swelling in the arm, can be physically debilitating and puts women at greater risk for infections as well as psychological stress.

The results are an interim analysis of an ongoing controlled trial called PREVENT, launched in 2014 and led by Ridner. The analysis involved 508 participants who had been monitored for a year or longer. Participants identified at risk for lymphedema received compression sleeves and gauntlets and were instructed to wear them 12 hours daily for 28 days to prevent progression to lymphedema. Patients who developed lymphedema reached their endpoint with the trial and were referred to clinicians for complex decongestive physiotherapy (CDP).

“CDP is resource intensive and costly,” Ridner said. “Lymphedema therapists are not accessible everywhere and mostly are in metropolitan areas. You go an hour-and-a-half in any direction outside of Nashville, for example, and we can’t find people to treat these patients.”

Clinicians have traditionally used tape measures to monitor breast cancer patients for lymphedema, but that method can vary greatly depending upon how a clinician does this.

“Tape measure is the most commonly used method around the world even though it is fraught with error,” Ridner said. “To get accurate measurements for a research study, there is an incredible amount of training to teach all the sites in this international study how to measure the same way. I do annual fidelity oversight visits to every single site to make sure there has not been any slippage in the protocol.”

BIS is a painless and noninvasive procedure that entails running an electronic signal through the body. The technology is similar to electronic monitors for body mass index, but much more refined.

Although the study showed that participants in the BIS experienced reduced rates of progression to lymphedema requiring CDP, the tape measure group triggered an intervention more often and earlier. The median time that triggered an intervention in the tape measure group was 2.8 months versus 9.5 months for the BIS group.

“It is possible that at three months post-surgery in some patients there remains a generalized, whole-arm inflammatory response that is identified by tape measure,” the analysis states. “Increased extracellular fluid may not be a major factor in that volume change.”

Ridner and the research team will evaluate the factors associated with triggering for both groups going forward.

“We had statistically significant more people trigger an intervention that were in the tape group than in the BIS group, which was contrary to what many people thought would have happened in the study. One of the concerns about BIS in general was that it might generate false positives and we might psychologically distress people,” Ridner said. “That was never my experience in the 15 to 16 years I’ve been working with the technology.”

The PREVENT trial has enrolled a total of 1,201 participants with 325 of them being patients of the Vanderbilt Breast Center. The findings released at the annual meeting of the American Society of Breast Surgeons involved the first 500 to have been monitored for 12 months or longer. The trial is anticipated to continue through December 2020. Other sites involved in the trial include Alleghany General Hospital, Columbia University Medical Center, Mayor Clinic (Jacksonville, Fla.), University of Louisville, Macquarie University (New South Wales, Australia), MD Anderson Cancer Center, University of Kansas Medical Center, Cleveland Clinic and Southeast Health Southeast Cancer Center (Cape Girardeau, Mo.).

Co-investigators of the study from Vanderbilt include Mary Dietrich, PhD, MS, VUSN, and Vandana Abramson, MD, Vanderbilt-Ingram Cancer Center. Other co-investigators are Chirag Shah, MD, Cleveland Clinic, and Frank Vicini, MD, 21stCentury Oncology.

A UCR-led team has discovered two Jupiter-sized planets about 150 light years away from Earth that could reveal whether life is likely on the smaller planets in other solar systems.

“We believe planets like Jupiter have profoundly impacted the progression of life on Earth. Without them, humans might not be here to have this conversation,” said Stephen Kane, lead study author and UCR associate professor of planetary astrophysics. “Understanding how many other stars have planets like Jupiter could be very important for learning about the habitability of planets in those systems.”

Along with liquid water oceans, Kane said astronomers believe such planets have the ability to act as ‘slingshots,’ pulling objects like meteors, comets, and asteroids out of their trajectories en route to impact with small, rocky planets.

Many larger planets have been found close to their stars. However, those aren’t as useful for learning about the architecture of our own solar system, where the giant planets including Saturn, Uranus and Neptune are all farther from the sun. Big planets far from their stars have, until now, been harder to find.

A study recently accepted for publication in the Astronomical Journal details how Kane’s team found success in a novel approach combining traditional detection methods with the latest technologies.

One popular method of searching for exoplanets — planets in other solar systems — involves monitoring stars for “wobble,” in which a star moves toward and away from Earth. The wobble is likely caused by the gravitational pull a nearby planet is exerting on it. When a star wobbles, it’s a clue there may be an exoplanet nearby.

When the planet is far from its star, the gravitational pull is weaker, making the wobble smaller and harder to detect. The other problem with using the wobble detection method, Kane said, is that it just takes a long time. Earth only takes a year to orbit the sun. Jupiter takes 12, Saturn takes 30, and Neptune takes an astonishing 164 years.

The larger exoplanets also take many years to circle their stars, which means observing a complete orbit could engulf an astronomer’s entire career. To accelerate the process, Kane and his team combined the wobble method with direct imaging. This way, if the team thought a planet might be causing wobble, they could confirm it by sight.

Obtaining a direct image of a planet quadrillions of miles away is no simple task. It requires the largest possible telescope, one that is at least 32 feet long and highly sensitive. Even from this distance, the light of the stars can overexpose the image, obscuring the target planets.

The team overcame this challenge by learning to recognize and eliminate the patterns in their images created by starlight. Removing the starlight allowed Kane’s team to see what remained.

“Direct imaging has come a long way both in terms of understanding the patterns we find, and in terms of the instruments used to create the images, which are much higher resolution than they’ve ever been,” Kane said. “You see this every time a new smartphone is released — the camera detectors are always being improved and that’s true in astronomy as well.”

In this project, the team applied the combination of wobble and imaging method to 20 stars. In addition to the two being orbited by giant Jupiter-like planets that had not been previously discovered, the team also detected a third, previously observed star with a giant planet in its system.

Going forward, the team will continue to monitor 10 of the stars where planetary companions could not be ruled out. In addition, Kane is planning a new project to measure how long it takes these exoplanets to complete rotations toward and away from their stars, which cannot currently be measured.

Kane’s team is international, with members at the Australian Astronomical Observatory, University of Southern Queensland, University of New South Wales and Macquarie University in Australia, as well as at the University of Hertfordshire in the United Kingdom. They are also spread across the U.S. at the National Optical Astronomy Observatory in Tucson, AZ, Southern Connecticut State University, NASA Ames Research Center and Stanford University in California and the Carnegie Institution of Washington in D.C.

“This discovery is an important piece of the puzzle because it helps us understand the factors that make a planet habitable and whether that’s common or not,” said Kane. “We are converging rapidly on answers to this question that the past 3,000 recorded years of history could only wish they had available to them.”