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Thursday, August 18, 2022

New study used marine monitor radar system to monitor California marine protected areas

Findings suggest fishers cluster outside MPAs to potentially benefit from better fishing opportunities

MAR COMMUNICATIONS

M2 System in Central California — IMAGE: MARINE MONITOR (M2) RADAR SYSTEM MONITORED ACTIVITY NEAR THE PIEDRAS BLANCAS LIGHT STATION IN CENTRAL CALIFORNIA. view more
CREDIT: PROTECTEDSEAS

Palo Alto, CA—Aug. 2,, 2022—A new study found that boaters often cluster along the edges of marine protected areas (MPAs) off the coast of California. These new findings suggest that fishers are aware of the MPA boundaries and cluster just outside them to potentially benefit from better fishing opportunities by "fishing the line."

The study, recently published in PLOS ONE, used the ProtectedSeas Marine Monitor (M2) autonomous data collection tool to continuously monitor vessel activity 24 hours a day, 7 days a week for a year in the vicinity of five state-managed MPAs near San Diego, Santa Barbara and Cambria. The M2 systems, which combine marine radar with custom software, were deployed to record the movement of boats on the water, allowing researchers to measure boat activity continuously in and around MPAs for the first time.

The network of M2 systems in California are managed by ProtectedSeas and site partners based at each location.

The researchers identified specific boat movements and found that overall, 40 percent more boating activity occurred in the vicinity of MPAs compared to the surrounding areas. A well-documented benefit of MPAs is the “spillover” of marine life from inside an MPA into the surrounding areas.

"Most activity occurred at or beyond MPA edges, and not within the area itself,” said ProtectedSeas researcher Samantha Cope, the lead author of the study. “This suggests that boaters are aware of the MPA and that the areas are serving their purpose of creating safe refuges for ocean life regeneration. Fishers see a benefit from spending time near the area because MPAs are working.

The researchers found that boating activity clustered at MPA edges occurred at all five locations. Clustering intensified at the southern California MPAs during both commercial and recreational spiny lobster seasons, a valuable fishery in the state. During the commercial spiny lobster season, clustering was 30 times greater also at the Campus Point State Marine Reserve near Santa Barbara.

"Conservation work needs to be driven by data, and M2 helps us understand trends in what's happening in MPAs," said study co-author Jess Morten, a researcher with the California Marine Sanctuary Foundation, a site partner with M2 in California.

MPAs in California primarily restrict fishing activities to conserve valued species and habitats. When fishing activity is concentrated at MPA edges, it suggests that fish may be more abundant closer to the MPA compared to elsewhere in the local area. Monitoring human activity can help managers evaluate both the ecological and community benefits of the MPA, detect patterns in boat activity and other human uses, and ensure MPA regulations are followed.

The M2 system provided researchers with an independent method for continuously documenting activity. "We specifically designed M2 to monitor important marine places at a cost that was realistic for local managers,” said M2 Product Manager and study co-author Brendan Tougher. "This research shows that M2 is an accessible and robust tool for monitoring MPAs."

The state's first MPA Decadal Management Review is currently underway to evaluate the existing network of MPAs. Investigating human activity near MPAs is important for evaluating the success of current ocean protections.

There are currently 18 active M2 systems globally, with six of them in California, and many deployed internationally in developing countries.

"As a 'low-tech' solution for more efficient MPA monitoring, M2 is especially valuable for anyone with limited technical experience or resources since people can be quickly trained on how to use and interpret data from our systems," said Tougher.

Hot spots of activity occurred at MPA boundaries, and this activity was generally most common at mid-day and on weekends. There was less activity overall at the site in central California that monitored the Piedras Blancas State Marine Reserve and State Conservation Area, likely due to its remote location. But hot spots at MPA boundaries were still present.

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The mission of ProtectedSeas is to provide open data and monitoring solutions to enhance awareness of and compliance with ocean protections. Learn more at: https://protectedseas.net/

JOURNAL

PLoS ONE

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Coastal radar as a tool for continuous and fine-scale monitoring of vessel activities of interest in the vicinity of marine protected areas

Department of Energy announces $10 million for research on environmental systems science

Projects address the role of plant-mediated water redistribution, wildfires and floods, and fungal networks on environmental system processes

Grant and Award Announcement

DOE/US DEPARTMENT OF ENERGY

WASHINGTON, D.C. - Today, the U.S. Department of Energy (DOE) announced $10 million in funding for 12 projects to universities, academic institutions, federal research labs, and nonprofits within the area of Environmental System Science (ESS) research. Grants will focus on studies intended to improve the understanding and representation of the impact of wildfires and floods on ecosystems and watersheds, as well the role of plant-mediated water redistribution and fungal networks in shaping ecosystem and watershed function.

“The DOE invests in Earth system science by tightly coordinating field-based experimental research with system modeling,” said Gary Geernaert, DOE Acting Associate Director of Science for Biological and Environmental Research (BER). “This approach enables more rapid progress in scientific discovery and improves our ability to advance climate predictions for extreme environmental conditions.”

Current models lack appropriate representation of important interactions among physical, hydrological, biogeochemical, and ecological aspects of the Earth system. By coupling experiments, observations, and models, interdisciplinary teams of scientists will work to unravel these complex processes to improve understanding of the structure and function of watersheds and ecosystems across spatial and temporal scales. It is expected that the grants will advance critically needed observational and experimental research and model development aimed at improving the accuracy of today’s Earth and environmental system models and predictive capabilities.

Projects include research funded under three topical areas:

Plant-Mediated Ecohydrology projects will investigate plant hydraulic redistribution and its influence on ecosystem/watershed function.
Wildfire or Floods and System Processes projects will improve understanding and model representation of the impacts and responses of environmental processes following wildfires or floods.
Fungal Network Shaping of System Function projects will investigate fungal-mediated plant-soil interactions in response to environmental factors or stresses.

The projects were selected by competitive peer review under the DOE Funding Opportunity Announcement for Environmental System Science sponsored by the BER program within the Department’s Office of Science.

Total funding is $10 million for projects lasting up to three years in duration, with $10 million in Fiscal Year 2022 dollars and outyear funding contingent on congressional appropriations. The list of projects and more information can be found here.

When particles move

A deep dive into the relationship between cohesion and erosion

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - SANTA BARBARA

Comparisons of Grains — IMAGE: THE POLYMER-COVERED SPHERICAL GLASS BEADS USED IN THE EXPERIMENTS. THE GRAINS AT THE TOP HAVE A VERY THIN COATING AND NO COHESION; THOSE AT THE BOTTOM HAVE A MUCH THICKER COATING AND ARE COHESIVE. view more
CREDIT: UC SANTA BARBARA

Landslides are one striking example of erosion. When the bonds that hold particles of dirt and rock together are overwhelmed by a force — often in the form of water — sufficient to pull the rock and soil apart, that same force breaks the bonds with other rock and soil that hold them in place. Another type of erosion involves using a small air jet to remove dust from a surface. When the force of the turbulent air is strong enough to break the bonds that hold the individual dust particles, or grains, together and cause them to stick to the surface, that’s erosion, too.

In the pharmaceutical industry, cohesion/erosion dynamics are immensely important to successfully process powders to make medicines. They also play a key role in another, rather far-removed, example: landing a spacecraft on a surface, such as the moon. As the spacecraft lowers, the exhaust of its engines causes the granular material on the surface to erode and be transported. The displaced material forms a crater, which must be of the correct dimensions; too narrow or too deep, and it will cause the spacecraft to tip over.

We often encounter divided materials that are composed of small particles — think sand on the beach, soil, snow and dust — that can be affected by more than just frictional forces, sharing some additional cohesive forces with their neighbors. While cohesion acts only between a particle and its immediate neighbors, it also produces macroscopic effects; for instance, causing divided bits of material to aggregate and adding additional strength to the composite. Cohesion is what causes powders, such as flour, to clump and enables us to make castles on the beach by adding a small amount of water to dry sand.

Alban Sauret, an associate professor in the UC Santa Barbara Mechanical Engineering Department, is keenly interested in these processes. Published in the journal Physical Review Fluids, his group, including first-year Ph.D. student Ram Sharma and colleagues in France, present new research examining how cohesion between particles can influence the onset of erosion. Using a recently developed technique that allows them to control the cohesion between model grains and then running experiments in which they used a jet of air to displace the grains, they were able to gain a better understanding of cohesion, which holds particles together; erosion, which causes them to separate; and transport, which involves how far the displaced particles then travel.

The research offers an approach for quantifying how the magnitude of cohesion changes the amount of local stress needed to start erosion. This understanding could be used in civil engineering, say, to measure the strength and stability of soil in an area where construction is planned. But the researchers also hope that their model will provide empirical evidence for a physical theory of erosion that includes cohesion and is relevant to a broad range of applications, from removing dust from solar panels (dust can reduce energy production by as much as 40%) to landing rockets on other planets.

In the presence of external forces, such as from wind or water, the cohesion between particles can be overcome. The onset of erosion refers to the point at which the drag force, exerted by fluid or air, causes particles to lose contact with the granular bed, becoming separated both from each other as neighbors and from the surface to which they adhere. This captures our fairly elementary, current understanding of erosion: if local external forces on a particle are larger than the forces keeping it in place, it erodes — another way of saying that it is displaced.

As fluids or air apply larger stresses, such as by moving fast enough to become turbulent flows, they can cause greater erosion. An exceedingly broad range of turbulent-flow configurations acting on an equally broad range of materials lead to the erosion we see, at the macro level, in the forms of enormous canyons, worn down over eons by turbulent rivers, and gigantic sand dunes, shaped by turbulent air currents. Surprisingly, given that erosion drives the sediment cycle and constantly reshapes the surface of the Earth, the current understanding of erosional forces is not adequate to explain the rich variety of resulting landforms.

While erosion of non-cohesive grains can be predicted satisfactorily, the interplay between turbulent flows and erosion in the presence of inter-particle cohesion has not been well researched. But it deserves study, Sauret says, because “Cohesion is everywhere! If you are modeling something as simple as how to clean a surface, for instance, and your model does not correctly account for cohesion, you will likely end up taking a wrong approach — and still have a dirty surface.”

To control the cohesion between particles, the researchers applied a polymer coating to identical glass spheres (analog for particles) with a diameter of .8 millimeter. The thickness of the coating could be increased or decreased precisely to increase or decrease cohesion. The turbulent flow is modeled by a variable jet of air aimed at the granular bed.

The experiments enabled the team to determine a scaling law for the threshold at which erosion overcomes interparticle cohesion, regardless of the specifics of the system, such as particle size. By quantifying the relationship between these two forces, the research presents a technique that can be used to predict the erosion threshold for different sizes of grains.

The results of this study, says Sauret, can be most directly applied to the process of removing cohesive sediments, such as dust and snow, from surfaces such as solar panels.

CAPTION

The nozzle (top) creates a flow of turbulent air that interrupts cohesion between particles (below) and the surface, leading to erosion and transport of the particles.

CREDIT

UC Santa Barbara