However, when Long and his students looked for seagrass meadows where he had seen them in previous years, there were only a few shoots of dying Zostera marina eelgrass, a type of seagrass.

That prompted Long and Jordan Mora, a restoration ecologist with the Association to Preserve Cape Cod, to analyze decades’ worth of local environmental monitoring data to find out what has happened to the estuary. What they determined is that Waquoit Bay has shifted from a benthic to a pelagically-dominated ecosystem due to human causes, including an excess influx of nutrient pollution along with climate change.

That disruption to Waquoit Bay’s ecosystem presents broad concerns about the fate of coastal estuaries worldwide, according to the researchers.

In addition, the researchers point to the importance of tapping into and analyzing long-term monitoring data to better understand the changes to Waquoit Bay and potentially to other estuaries as well.

The water quality and overall health of estuaries continue to degrade due to excess nutrients from leaching septic systems, agricultural runoff, and other anthropogenic sources, the researchers note. In addition, warming water temperatures from climate change, particularly in the northeastern United States, exacerbates the nitrogen loading problem by reducing dissolved oxygen levels and accelerating microbial metabolism which further reduces oxygen levels.

“This shift toward pelagic dominance in Waquoit Bay may indicate that other eutrophic and warming estuaries may also shift toward pelagic dominance in the future, as the Northeastern US is one of the fastest warming,” according to “Deoxygenation, Acidification and Warming in Waquoit Bay, USA, and a Shift to Pelagic Dominance,” a paper co-authored by Long and Mora published in Estuaries and Coasts, the journal of the Coastal and Estuarine Research Federation. “The range of nitrogen loading across the Waquoit Bay sub-watersheds is comparable to the range of nitrogen loading across 90% of the world’s estuaries making it an ideal site for investigating eutrophication impacts.”

The scientists note that their research results in Waquoit Bay “cannot disentangle the contributions of global change or eutrophication to estuary decline. However, they do point to a potential combined effect that may result in other similar estuaries becoming dominated by pelagic metabolism in the future, and the resulting deleterious effects of harmful algal blooms, hypoxia, and the loss of species diversity and ecosystem function.”

The researchers’ analyses revealed recent and unexpectedly large increases in chlorophyll a concentrations, an indicator of microalgal blooms, in the water column throughout the estuary, which coincided with ongoing decreases in macroalgal density on the bottom of the estuary. In addition, the analyses showed an increase in temperature over the last 20 years and significant declines in oxygen and pH levels, among other changes.

The analyses relied on long-term monitoring data collected over decades from two monitoring programs coordinated by the Waquoit Bay National Estuarine Research Reserve, including the reserve’s System-Wide Monitoring Program and the Waquoit BayWatchers, that latter of which is a citizen science water quality monitoring program.

One of the main objectives of the current study was to apply time-series analysis techniques and substantial knowledge about the history of the monitoring programs to reveal long-term trends in water quality, according to the paper. “These methods can be applied to other monitoring data to advance the knowledge gained from similar monitoring programs, enhance our understanding of estuarine biogeochemistry, and investigate estuarine responses to long-term change,” the paper states.

Long said eelgrass provides a number of ecosystem benefits including stabilizing sediments and offering habitat for a variety of organisms. In addition, eelgrass is a great indicator of good estuarine water quality and also serves as a carbon sink.

“Carbon storage is extremely important across the world, and we’re actively trying to figure out ways to store and sequester carbon. Seagrass meadows represent a really significant and efficient carbon storage sink,” Long said. “Let’s not lose the seagrass meadows and the carbon sequestration that we already have in place, and let’s actively maintain and restore seagrass meadows. With the loss of seagrass meadows, such as what we’ve seen in Waquoit Bay, we’re actively releasing that carbon back to the atmosphere.”

Long added that using environmental monitoring data helped to put together the story of the switch from a seagrass-dominated system to a macroalgal-dominated system from the 1980s to the present in Waquoit Bay. Without the long-term data, gradual changes to the system would be more difficult to detect, he said.

“This paper isn’t just significant because it demonstrates that the estuaries on southern Cape Cod, and more generally the northeastern US, are entering a new level of degradation where not even macroalgae or seaweeds can persist, but also because it provides clear evidence that long-term monitoring programs are extremely important and worth maintaining,” said Mora, who worked at the Waquoit Bay National Estuarine Research Reserve for 10 years collecting water quality and submerged vegetation data with visiting scientists, volunteers, and other staff, and witnessed the gradual decline in habitat quality firsthand.

“My hope is that by showing the impact of increasing temperatures on already degraded systems, this paper will help facilitate local and regional management discussions and accelerate the decision-making needed to mitigate the overload of nutrients in our estuaries,” Mora added.

The paper notes that “there is an urgent need to address wastewater handing to improve the estuary, especially in the face of global changes.”

Long said, however, that if local stressors including nutrient pollution can be addressed, and if we can reduce carbon emissions and slow down global warming and the amount of carbon that diffuses into the ocean, “we could turn this situation around before it happens to many similar estuarine systems across the world, preserve the valuable ecological functions of seagrass meadows, and enable their carbon storage potential.”

Funding to support the Marine Biological Laboratory macrophyte data collection was provided by Woods Hole Sea Grant. This research was funded by a WHOI Independent Research and Development grant.?

In a new study, University of Missouri researcher Jeffrey Wood introduces the “ecosystem wilting point” concept, which explains how whole forests respond to drought. Wood and his research team found that when forests reach their ecosystem wilting point, they are less able to function properly, which includes their ability to absorb carbon dioxide. To learn how the forest behaved during periods of drought, Wood combined measurements of evapotranspiration (the loss of water to the air) and ecosystem water status, which indicates how hydrated the forest is.

“The motivating reason for being able to understand the drought response of forests is that, globally, drought is important now, and it’s not expected to get better,” said Wood, an assistant professor in the College of Agriculture, Food and Natural Resources. “We wanted to develop a better way to understand and characterize these ecosystems, so we can use that information to help with modeling the dynamics of vegetation over time and better understand the future impact on these ecosystems.”

In pursuit of understanding the nuances of forests’ stress, Wood and his co-authors reanalyzed data collected during an extreme drought event that took place in 2012 in Baskett Forest, an outdoor laboratory of 2,266 acres located five miles east of Ashland, Missouri. This study uses a method that was initially developed to understand the interaction between water and an individual cell. That method was later applied to leaves, and then Wood extended it in this study to analyze a whole forest.

In this study, this oak-hickory forest in central Missouri reaches its ecosystem wilting point between 2-4 weeks of extreme drought. At that point, the forest would need soaking rainfall to rejuvenate.

“The ecosystem wilting point is functionally significant in that when the forest passes that threshold, there is a noticeable change in how the forest is behaving,” Wood said. “When you get into that highly stressed state, the forest is quite unresponsive to changes in the environment. So, when the sun comes up, you would tend to think that the forest turns on and starts to photosynthesize, but if the forest is past its ecosystem wilting point, it has a very limited capacity to respond to the changes in light in terms of carbon dioxide uptake because it’s under so much stress.”

This study offers insight into the water relations of whole forests, a useful tool for researchers exploring how forests across the globe handle temperature variations — something Wood emphasizes is important as scientists manage forests in a way that prepares them to better withstand climate change.

“Forests are pretty important; they’re connected to weather and the climate in ways that we still don’t fully understand,” Wood said.

This permanently frozen landscape in the Arctic tundra, which has kept vast amounts of carbon locked away for thousands of years, is at risk of thawing and releasing greenhouse gases into the atmosphere.

The United Nation’s Intergovernmental Panel on Climate Change has identified the possibility of soil subsidence leading to a feedback loop that could trigger a rapid thaw as a major concern in the decades ahead. Accelerated thawing caused by uneven land subsidence has been observed on smaller scales over shorter time frames, but the IPCC’s assessments were uncertain as to what may happen over the long term.

That’s where ORNL stepped in with its Advanced Terrestrial Simulator, or ATS, a highly accurate, physics-based model of the region’s hydrology fed by detailed, real-world measurements to help scientists understand the land’s evolution.

What they found is that even though the ground will continue to sink as big ice deposits melt, the uneven subsidence also leads to a drier landscape and limits the process’s acceleration through the end of the century, as described in the Proceedings of the National Academy of Sciences.

“Improved drainage results in a drier landscape over a decadal timescale, and the process then becomes self-limiting,” said Scott Painter, who leads the Watershed Systems Modeling group at ORNL.

The scientists focused on a large region of the tundra characterized by ice wedges — long pieces of ice that crack the surface and extend belowground to create polygonal forms in the Arctic landscape. The cryo-hydrology simulations were informed by measurements gathered in the polygonal tundra.

The ATS was first developed for the Department of Energy’s NGEE Arctic project led by ORNL, focused on observations, experiments and modeling of the environmental processes at play in the region to improve climate predictions.

“We looked at the microtopography caused by these ice wedges in the subsurface and how that controls the flow of water,” Painter said. “Ours is the first capability to capture the effect of changing microtopography and represent it in climate models.”

Painter added that the team has a high degree of confidence in the model since it was developed for NGEE Arctic and has been evaluated against the project’s real-world observations.

He noted that most models, including ORNL’s, are in agreement in generally projecting large amounts of carbon thaw in the Arctic as temperatures rise. “But here, we have identified that one of the most worrisome processes, this runaway thawing due to subsidence, is unlikely to occur over a long time frame.”

The study pointed out other implications of a drying landscape. “As the polygonal tundra gets very dry, by the year 2100 it could have ecological impacts for migratory birds, which use these ecosystems as breeding grounds,” Painter said.

Other scientists collaborating on the study include ORNL’s Ethan Coon; Ahmad Jan, formerly of ORNL and now at the NOAA-affiliated Office of Water Prediction; and Julie Jastrow of Argonne National Laboratory.

The research was supported by NGEE Arctic, which is sponsored by the DOE Office of Science’s Biological and Environmental Research Program and led by ORNL, and BER’s Environmental System Science Program at Argonne. NGEE Arctic supported the original development of ATS as well as recent enhancements to incorporate subsidence into the model.

The futuristic sounding treatment would work by switching on LED lights embedded close to a tumour, which would then activate biotherapeutic drugs.

These new treatments would be highly targeted and more effective than current state-of-the-art cancer immunotherapies.

New research published today reveals the science behind this innovative idea.

It shows how the UEA team have engineered antibody fragments — which not only ‘fuse’ with their target but are also light activated.

It means that in future, immunotherapy treatments could be engineered to attack tumours more precisely than ever before.

The principal scientist for this study, Dr Amit Sachdeva, from UEA’s School of Chemistry, said: “Current cancer treatments like chemotherapy kill cancer cells, but they can also damage healthy cells in your body such as blood and skin cells.

“This means that they can cause side effects including hair loss, feeling tired and sick, and they also put patients at increased risk of picking up infections.

“There has therefore been a very big drive to create new treatments that are more targeted and don’t have these unwanted side-effects.

“Several antibodies and antibody fragments have already been developed to treat cancer. These antibodies are much more selective than the cytotoxic drugs used in chemotherapy, but they can still cause severe side effects, as antibody targets are also present on healthy cells.”

Now, the UEA team has engineered one of the first antibody fragments that binds to, and forms a covalent bond with, its target — upon irradiation with UV light of a specific wavelength.

Dr Sachdeva said: “A covalent bond is a bit like melting two pieces of plastic and fusing them together. It means that drug molecules could for example be permanently fixed to a tumour.

“We hope that our work will lead to the development of a new class of highly targeted light-responsive biotherapeutics. This would mean that antibodies could be activated at the site of a tumour and covalently stick to their target upon light activation.

“In other words, you could activate antibodies to attack tumour cells by shining light – either directly on to the skin, in the case of skin cancer, or using small LED lights that could be implanted at the site of a tumour inside the body.

“This would allow cancer treatment to be more efficient and targeted because it means that only molecules in the vicinity of the tumour would be activated, and it wouldn’t affect other cells.

“This would potentially reduce side effects for patients, and also improve antibody residence time in the body.”

“It would work for cancers like skin cancer, or where there is a solid tumour – but not for blood cancers like leukaemia.

“Development of these antibody fragments would not have been possible without pioneering work from several other research groups across the globe who developed and optimised methods for site-specific incorporation of non-natural amino acids into proteins expressed in live cells.

“We employed some of these methods to site-specifically install unique light-sensitive amino acids into antibody fragments.”

If the researchers are successful in the next stages of their work, they hope to see the ‘next generation’ light-activated immunotherapies being used to treat cancer patients within five to 10 years.

This research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Wellcome Trust. It was led by the University of East Anglia with assistance from the proteomics facility at the John Innes Centre.