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Economic Value of Salt Marshes under Uncertainty of Sea Level Rise: A Case Study of the Narragansett Bay
No full textSalt marshes are an integral part of coastal ecosystems that are changing rapidly with sea level rise (SLR). Because marshes provide important ecosystem services, such as carbon sequestration and shoreline protection, it is critical to understand how their economic benefit values are likely to be affected by SLR. Such change, however, depends on the capacity of marshes to adapt to flooding by migrating inland. This study provides the economic value of changes in carbon and non-carbon benefits using predicted changes in salt marsh coverage in Narragansett Bay, Rhode Island under three SLR scenarios and two marsh adaptation conditions. We apply regional carbon prices and a value function transfer approach to value other salt marsh service values. Results indicate an average annual value of 2,537/acre for non-carbon ecosystem services. This yields a mean discounted value of 659 M
Patron-client relationships shape value chains in an Indonesian island-based fisheries system
No full textFishing is vital to millions of people in Southeast Asia. Overfishing along with climate-induced stressors have presented significant challenges to managers. Solutions for fisheries management in the region, however, tend to narrowly focus on production and catch restrictions despite the importance of local economies and relationships. For example, the role of networks known as patron-client systems are understood by scholars and local populations as important drivers of fisheries exploitation in Indonesia, but policy is rarely directed at them. Here, we perform value chain analysis to better understand the socioeconomic factors that mediate fish catch, distribution, and governance outcomes in an Indonesian fishing community. The community\u27s social context spurred the following research questions: i) In what ways does the regional fish trading system influence fisheries value chains; and ii) How does the current structure of trade align with fisheries and fishing actors on the island? Survey-based fieldwork collected data on species composition, revenue, and buyer/seller relationships from the point of catch to sale. These results showed that patrons earn disproportionate trading benefits compared to fishing clients, including higher revenues, bargaining power, and flexibility from their central position as lenders. Findings also revealed a strong connection between pelagic-based fishing crews and the wider market system, which mediates the trade of fish off-island. Given the links between trading hierarchies and fish flows in our study, we argue that efforts to enhance fisheries governance would be most effective if introduced through off-island auctioneers since they have significant power in controlling fish catch and distribution
Fishing characteristics and catch composition of the sardinella fishery in Ghana indicate urgent management is needed
No full textThe sardinella (Clupidae) fishery in Ghana is vital to food and economic security for millions of people along the coast. Sardinella catches, however, have recently been declining and little is known about the current fishery characteristics. To address this gap, we sampled 8 sites along the coast of Ghana from 2017–2018 and collected data on over 14,000 fishes from 332 fishing trips of fishers targeting the two species of sardinella locally exploited, i.e. the round sardinella (Sardinella aurita) and the flat sardinella (Sardinella maderensis). The primary fishing gears were beach seines, purse seines, and gill nets. We distinguished three distinct types of purse seines based on mesh size: “poli” had mesh sizes of 3 cm or below (despite regulations deeming these illegal); “watsa” had mesh sizes of greater than 3 cm; and “poli-watsa” had a combination of mesh sizes across this range. Differentiation of gill nets was based on either monofilament (called “set net”) or cotton (called “ali”). These fishing nets ranged in length from 54 m to almost 1000 m, and poli-watsa was the most dominant gear as it was responsible for 37% of the total catch. Fishing vessels ranged from 5 – 23 m and crew sizes were from 2 – 30 individuals per vessel. Fish dissections and landings data indicated that S. aurita had a length at maturity of 14.7 cm and 62% of landed individuals were immature. The length at maturity for S. maderensis was 15.2 cm and 75% of landings were immature. Poli-watsa was the dominant gear for S. aurita, which was captured in significantly deeper areas (mean = 31.8 m) than S. maderensis, which was mostly caught with gill nets at a mean depth of 22.8 m. Considering the dominance of juveniles in the landings, coupled with recent declines in catch per unit effort, management is urgently needed to prevent collapse of this economically, socially, and ecologically important fishery
Equitable Belonging via Information Literacy: Amanda Izenstark, MLIS • University of Rhode Island, University Libraries • POD22, November 17, 2022 Equitable Belonging via Information Literacy Empowering Teachers to Empower Learners
Get PDFAs critical educators and learners, we continually encounter a changing information landscape necessitating (re)considerations of our responsibilities as consumers and producers of knowledge. This workshop offers a window into a High Impact Teaching Seminar created by librarians and educational developers at the University of Rhode Island to intentionally integrate accessible Information Literacy (IL) skills for all students. Through a reflective exploration of IL threshold concepts such as scholarly conversation, authority, information creation, and strategic exploration, participants will learn about the seminar’s theoretical framework and structure, engage in sample activities, and consider possible applications at their own institutions
Replacing humans with machines: a historical look at technology politics in California agriculture
No full textMedia outlets, industry researchers, and policy-makers are today busily extolling new robotic advances that promise to transform agriculture, bringing us ever closer to self-farming farms. Yet such techno-optimist discourse ignores the cautionary lessons of past attempts to mechanize farms. Adapting the Social Construction of Technology framework, we trace the history of efforts to replace human labor with machine labor on fruit, nut, and vegetable farms in California between 1945 and 1980—a place and time during which a post-WWII culture of faith in the beneficence of technoscience applications to agriculture reached an apex. The degree to which and forms whereby mechanization gains momentum hinges on whether, how, and among whom a technological frame for mimicking human capabilities and supplanting workers coalesces. These frames, we find, vary considerably across crops, reflecting complex interactions of biology, farmer and farm worker behavior, industry supply chains, agricultural research and development, financial flows, and beliefs about labor, race, gender, and immigration. To tease out these complex dynamics, we draw directly from archival evidence to follow the development of cultivation and harvest machines through four cases spanning a spectrum of outcomes—tomatoes, nuts, peaches, and lettuce. In comparing across these cases, we find that although agricultural engineers, scientists, and their boosters framed mechanization as a triumphal narrative of progress in ‘human vs. nature’ conflicts, this techno-optimist rhetoric camouflaged deeper ‘human vs. human’ conflicts, particularly among agribusiness, farmers, and farm workers. We conclude with several insights that this historical study brings to the study of agricultural automation today
Simulated Impact of Ocean Alkalinity Enhancement on Atmospheric CO2 Removal in the Bering Sea
Get PDFOcean alkalinity enhancement (OAE) has the potential to mitigate ocean acidification (OA) and induce atmospheric carbon dioxide (CO2) removal (CDR). We evaluate the CDR and OA mitigation impacts of a sustained point-source OAE of 1.67 × 1010 mol total alkalinity (TA) yr−1 (equivalent to 667,950 metric tons NaOH yr−1) in Unimak Pass, Alaska. We find the alkalinity elevation initially mitigates OA by decreasing pCO2 and increasing aragonite saturation state and pH. Then, enhanced air-to-sea CO2 exchange follows with an approximate e-folding time scale of 5 weeks. Meaningful modeled OA mitigation with reductions of \u3e10 μatm pCO2 (or just under 0.02 pH units) extends 100–100,000 km2 around the TA addition site. The CDR efficiency (i.e., the experimental seawater dissolved inorganic carbon (DIC) increase divided by the maximum DIC increase expected from the added TA) after the first 3 years is 0.96 ± 0.01, reflecting essentially complete air-sea CO2 adjustment to the additional TA. This high efficiency is potentially a unique feature of the Bering Sea related to the shallow depths and mixed layer depths. The ratio of DIC increase to the TA added is also high (≥0.85) due to the high dissolved carbon content of seawater in the Bering Sea. The air-sea gas exchange adjustment requires 3.6 months to become (\u3e95%) complete, so the signal in dissolved carbon concentrations will likely be undetectable amid natural variability after dilution by ocean mixing. We therefore argue that modeling, on a range of scales, will need to play a major role in assessing the impacts of OAE interventions
Hands off the Drawers: TEMPO Drawer Lift Cart
Get PDFThe main objective of this project was to investigate how the drawers of the TEMPO system can be moved in an ergonomic and safe manner. This is done with the bare minimum of human force. To achieve this objective countless meetings were held with Hexagon and visitations to better understand the system and the problem at hand. After these meetings, the team was able to build a prototype that would later be used as a baseline for the upcoming modifications. After modifications were made the team was able to test the design to see how it worked, with respect to the problem definition at hand. Once testing was completed the team was able to redesign the product to better achieve what Hexagon wanted. Overall the team was able to accomplish building a successful lift for Hexagon and complete the design specification requirements
Centrifugal Nuclear Thermal Rocket
Get PDFThe National Aeronautics and Space Administration commissioned thirteen undergraduate mechanical engineering students from the University of Rhode Island to devise a system of mechanics to commence, maintain, and shutdown the rotation of a Centrifugal Fuel Element (CFE) in a Centrifugal Nuclear Thermal Rocket (CNTR). The rocket is the one of the latest projects of High Performance Nuclear Thermal Propulsion (HP-NTP) in public development, research, and experimentation by the United States of America, and is proposed to convoy a crewed mission to Mars and back in 420 days.
The elected thirteen students were allocated by the university into three teams: Team 19 (U92), Team 20 (Astronaught), and Team 21 (Team Rocket). Each team was further instructed with a more identifying project description. Two of the teams were advised to orient their goals more in alignment toward the aforementioned rotation of the CFE, while the third team had their task encompass the entirety of the CNTR. This third team: Team 21, composed of 4 students, was tasked with producing a full model of the CNTR.
The other two teams had their project definitions subdivided principally by the speed of rotation. Team 20, composed of 5 students, focused on the ”high-speed” rotation of the CFE (i.e., greater than 600RPM) and maintaining the CFE at 5000 RPM through a control system. Team 19, composed of 4 students, was administered the ”low-speed” division of the program (i.e., less than 600 RPM). As one can infer, these two teams had to work moderately in conjunction with one another in order to provide a smooth operation of the design in an actual application.
The three teams engineered a joint apparatus to prove the proposed design solutions for each of the teams’ respective goals. Specifically, Team 19 sought to provide testing data of a contactless method of rotation to the CFE through use of a motor, an optimized geometry of turbine blades within the CFE, and an invariable system of deceleration to the CFE. Many other secondary objectives for a theoretical full-scale utilization were incidentally and periodically excogitated over the duration of the two semesters, several of which will be noted in this report. However, given the magnitude of the project, these secondary objectives were not experimented upon using a physical model
Tree Climber Inventor
Get PDFTeam 16 was tasked with the problem of developing a device to climb a tree with the ability to work freely while the device is in the tree. To accomplish this, previous designs were thoroughly researched, specific materials and tree types were inspected by team members and a preliminary patent search was conducted to further the knowledge base of previous designs and ideas for the device. Conducted literature searches brought information about frame shape, orientation and weight as well as specific types of metals that should be used for a lightweight but durable design. The team generated 120 design concepts, classified them into groups and a Quality Function Deployment comparison was performed.
The design uses a low carbon steel frame with two wheels attached on either side of the tree that act as a cantilever to keep the device from falling. The far wheel is attached to the pivot end as this wheel is receiving no power and free spinning. The drive wheel is on the other side of the tree and is attached to the drive train. The operator is located behind the drive wheel to obtain more force on the tree from the cantilever in order to increase the factor of safety. The force from the drivetrain is designed to be powered by geared bike pedals but is also designed to be easily changeable with an electric motor. Through inspection of this prototype and SolidWorks Stress and Strain simulations, this design is deemed to fulfill the problem definition and requirements.
The accomplishments of this project involved many different aspects such as; welding, notching of pipes, sawing, and testing. Although the task was complete the team did fall short of having a successful tree bike. This project involved a huge learning curve for the group to be able to machine and weld. As a team, they learned how to weld and machine together while helping each other throughout. The frame was constructed and achieved a factor of safety much higher than required for the project. A gearbox was developed and 3D printed by Inkbit, a 3D printing company that sponsored the group. Everything needed for the project such as; brakes, mounts, axles, wheels, and various custom parts were completed and assembled. Unfortunately, the 3D printed gears would not refrain from slipping on the axles causing the TreeBike not to work properly. Testing for the project was successful. The tests completed were friction, weld strength, and corrosion of the material. All tests were done by developing a study and closely monitoring the results
Design of Fixture to Measure Impact Load
Get PDFTeam 26 was tasked with designing, developing and building a test fixture to measure impact loading incorporating an isolation mount. To start this project the team first had to gather a lot of research about the subject as the group members have only had one challenging class relating to the subject of dynamic properties; this class was System Dynamics. Through many hours of research including a literature and patent search the group was able to comfortably gauge the scope of the problem definition as well as the relative verbiage and vocabulary of the world of isolation mounts, impact testing and accelerometers. After the group felt confident about the previous work, a generation of 90 concepts (30 concepts each) were drawn out. These concepts were then put through a rigorous Quality Function Deployment comparison which in the end yielded the teams top 3 concepts. However after meeting with our sponsors and professors the design had to be altered in order to fully fulfill the requirements of the project. This design will be described below.
The design in this report utilized gravity as its main source of power to deliver a force to the isolation mount. A variable large mass is dropped from a set height which lands on a heavy duty lever; this lever looks very similar to a teeter totter. When this lever is struck on one side, the opposite side will rise and impact the hanging mass which has an isolation mount and base plate screwed into it. Throughout this process two accelerometers will be set up at various points along the apparatus including the hanging mass as well as the dropped mass. As this design came through it was realized that the lever would need some sort of split/spring mechanism to only strike the hanging mass once and not hold it after impact. This design can be seen in detail further into this report.
This design will be able to strike various isolation mounts at different impact loads for a variety of data. Through many 3D renderings, several meetings and a countless amount of hours spent assembling and testing, the team is proud to present the design solution to Raytheon Technologies