CTAHR NEWS
Anita Tsang M.S. Thesis Defense 8/9/2021 10:00 AM - 11:00 AM

Anita Tsang M.S. Thesis Defense

Evaluating the potential of an endemic Hawaiian soft coral, Sarcothelia edmondsoni, as a bioindicator of anthropogenic influence

Bioindicators, organisms which reflect an ecosystem’s health or condition, are frequently used in natural resource management and monitoring as an early warning sign for ecosystem degradation, allowing managers to recognize and address the issue at hand. Octocorals, soft corals belonging in the subclass Octocorallia, are used globally in coral reef monitoring protocols as an indicator of poor coastal water quality and nutrient contamination from human sources. Sarcothelia edmondsoni, an endemic Hawaiian octocoral, has had unusual high abundances in heavily polluted or developed areas around the main Hawaiian Islands, however, inadequate empirical evidence of how octocorals respond to environmental stressors hinders their use as an ecological indicator for coral reefs here in Hawai‘i. This study comprises a thorough evaluation of S. edmondsoni as a bioindicator, including assessments of the octocoral presence on spatial and temporal scales. To examine the temporal variation of S. edmondsoni, I conducted repeated benthic surveys on O‘ahu and Kaua‘i to quantify and track changes in populations. Environmental variables such as rainfall, temperature, and water quality were also collected to examine possible effects on octocoral abundance. To explore the spatial variability of S. edmondsoni, quantitative data was extracted from existing natural and anthropogenic land use spatial datasets to investigate correlations with species abundance on O‘ahu, Kaua‘i, and West Hawai‘i. Significant positive correlations with several environmental and anthropogenic factors such as human population and development levels support the use of S. edmondsoni as a bioindicator, which will be an important management tool for the conservation and protection of Hawai‘i’s coral reef ecosystems.

 

Date: August 9, 2021

Time: 10:00 AM HST

 

Zoom Meeting Link: https://us02web.zoom.us/j/86922861425

Meeting ID: 869 2286 1425

 

Committee members: 

Dr. Kirsten Oleson (chair)

Dr. YinPhan Tsang

Dr. Ku‘ulei Rodgers

Rainfall and Wildfires 21 July 2021

Rainfall and Wildfires

NREM Extension is interviewed for KHON2 newscast

“My research has found that… higher rainfall events can contribute more to fire risk down the road than real-time drought conditions,” Clay Trauernicht told KHON2 newscasters on Monday.

The Extension Specialist in Ecosystems and Fire in the Dept. of Natural Resources and Environmental Management was interviewed about recent brushfires occurring throughout the Islands.

Another contributing factor, he says, is that former agricultural lands are abandoned and overrun with invasive species. Twenty-five percent of Hawaiʻi’s landmass, about 1,000,000 acres, is dominated by these grasses and shrubs. On the other hand, fuel breaks would allow firefighters to come in and provide a safe environment for them to work.

“More importantly than fuel break stopping it is the fuel breaks that allow the firefighters to come in and provide a safe environment for the firefighters to work,” Clay said.

Read the full KHON2 story.

Nitrogen Numbers 20 July 2021

Nitrogen Numbers

TPSS joins an international effort to standardize the datasets

Nitrogen is the unsung hero of food production. The common element is an essential nutrient for plant growth and health. It is found in the chlorophyll needed for photosynthesis, in the amino acids that form proteins, in the adenosine triphosphate (ATP) compounds that release energy, and in the DNA that codes all plant life. Yet, because nitrogen leaks from agricultural systems, nitrogen deficiency is a common nutritional problem for plants. There’s also the question of the excessive use of nitrogen fertilizers and their effect on sustainable croplands, as well as the environment. In a new international study meant to improve nitrogen management and better understand the global nitrogen cycle, researchers compared 13 nitrogen budget datasets covering 115 countries and regions over the past half-century. The team included an investigator from the Dept. of Tropical Plant & Soil Sciences and found that, while most datasets collected show similar patterns, some estimates vary quite widely. The authors propose a common benchmark for nitrogen budgets, based on median values and the range of estimates.

“Nitrogen budgets tell us how much nitrogen is present and moving through our systems, but they’re notoriously difficult to construct on regional, national, and global scales,” says Tai Maaz. “This study provides an opportunity to create a benchmark so that people who are interested in comparing models can use a common dataset.”

In other words, it will facilitate apple-to-apple comparisons between model structures, rather than apple-to-orange differences in data inputs. Once this happens, scientists will have a much better tool to help in ecological modeling. In addition, policymakers commonly use nitrogen budgets to evaluate the risk of environmental impacts and set effective policies. 

“I am honored to be part of this international team of researchers led by Dr. Xin Zhang,” Tai says. “I am hopeful this study will help us find ways for more sustainable management. Proper and robust nitrogen budgeting is important for Hawaiʻi to protect our water and sensitive ecosystems from nitrogen pollution.”

The study, Quantification of global and national nitrogen budgets for crop production, appears in a recent Nature Food.

Hormones vs. Environment 20 July 2021

Hormones vs. Environment

HNFAS is studying how fish tolerate environmental changes

Many types of fish live in variable environments, meaning they must constantly adapt to changes in water salinity, temperature, and chemical content (i.e., pollutants). Therefore, exactly how a fish responds – in order to keep surviving, growing, and reproducing – is a subject of deep interest for scientists and commercial aquaculture producers who rely on controlled environments. Ongoing work in the Laboratory of Fish Endocrinology and Environmental Physiology, part of the Dept. of Human Nutrition, Food and Animal Sciences, may provide some clues. In three lines of work, the HNFAS investigators are helping to better understand 1) how fish hormones mediate the impact of a rise in temperature, 2) how the actions of these hormones are affected by age, and 3) how chemicals and pollutants released in the environment can interfere with fish growth and reproduction. “Our NSF-, NIH-, and NOAA-funded projects are targeted to better understand how specialized cells can sense the environment, respond to environmental change, and regulate functions essential for survival, such as salt-and-water balance, as well as functions essential for animal production, such as growth and reproduction,” says Andre Seale, principal investigator who is overseeing the research groups.

Hormones

The mechanisms responsible for how fish detect changes in salt concentration may be also at play when fish respond to a rise in temperature, notes HNFAS grad student Daniel Woo. He recently presented the evidence at the 45th annual Albert L. Tester Memorial Symposium and the 6th Biennial Conference of the North American Society of Comparative Endocrinology.

“This is because the cells that play an important role in detecting changes in salinity, through changes in volume and release of the hormone prolactin, also increase in volume and prolactin release when the temperature rises,” explains Andre.

Age

Are cells that make those adjustments, in response to environmental changes, affected by age? In a new study, “Age-Dependent Decline in Salinity Tolerance in a Euryhaline Fish,” Andre and collaborators make the case that age does affect those cells, at least in regard to changes in salinity. Their study appears in a recent Frontiers in Aging.

“Older fish have a lower capacity to survive a transfer from fresh water to seawater,” he says. “The ability to acclimate between widely changing salinities is a key characteristic of the Mozambique tilapia, a fish commonly used in aquaculture due to its environmental resilience. At least partly underlying this decline in salinity tolerance is a reduction in the responsiveness of older fish to the hormone, prolactin.”

Introduced Chemicals

In a review of ‘endocrine-disrupting chemicals’ – chemicals and pollutants that cause adverse effects in organisms by disrupting the actions of hormones – Fritzie Celino-Brady presents a comprehensive analysis of the experimental approaches used for investigating their effects on fish growth and reproduction. Her article, “Experimental Approaches for Characterizing the Endocrine-Disrupting effects of Environmental Chemicals in Fish,” appears in

Ahaolelo and Aliʻi 20 July 2021

Ahaolelo and Aliʻi

Hawaiʻi 4-H adapts to continue its traditions

‘Ahaolelo’ means “to come together for a meeting” in Hawaiian, and the Hawaiʻi 4-H Ahaolelo Leadership Conference is rich in that tradition, playing an important role in the development of our 4-H members.

Held at the University of Hawaiʻi at Mānoa campus, the Ahaolelo provides local youths who’ve completed 8th to 12th grade with an excellent opportunity to meet other 4-H members, make new friends, exchange ideas, develop communication and leadership skills – and learn more about UH and college life.

Last year, the Ahaolelo switched to a virtual Aliʻi Ceremony due to COVID-19, and merged with a 3-day online conference with Idaho and Washington 4-H’s STAC (State Teen Association Conference) to allow more teen participants.

This year, Hawaiʻi 4-H formed an Ahaolelo Planning Team, with the theme “Overcoming Challenges, Shaping the Future.” The events included a community service project with the ceremony in the evening. 

“Although this was a very difficult year, we used our 4-H skills to overcome challenges and shape the future,” said Kaitlin Kitagawa of Maui, who was an emcee at the Aliʻi Ceremony. In all, 40 teen delegates, adult volunteers, and 4-H Agents and Staff were able to attend. The delegates joined virtual workshops and were inspired by the special presenters:

  • Dr. Lauren Tamamoto, 4-H alumni from the Teddy Bears 4-H Club and Kapiʻolani Community College Food Scientist and Research Chef who collaborates with CTAHR.
  • Myself, presenting on “Head” life skills such as solving problems, making decisions, and practicing creativity.
  • Rebecca Kanenaka, past 4-H Club Leader of the Golden Ripples 4-H Club, retired microbiologist, and currently a 4-H Volunteer Resource Leader.
  • Hallie Cristobal, Kauaʻi 4-H and Intergenerational Junior Extension Agent, presenting on foods and nutrition.
  • Carli Yamamoto, 4-H alumni from the Aloha Kids 4-H Club and athletic trainer at Konawaena High School, presenting on empathy, determination, and resiliency.

The speakers shared engaging and hands-on learning, referencing their 4-H experiences, the challenges they faced, and how they overcame and moved forward. They also shared about their careers and how they got to where they are today.

“It kept the attention of the audience well and the workshops were fun!” wrote one 4-H participant.

 

Aliʻi Ceremony

To gracefully end the 4-H Ahaolelo, we also held an Aliʻi Ceremony in the evening at the UHM campus, with virtual links for participants on the Neighbor Islands. The ceremony is another 4-H tradition, called “Gifts to the Aliʻi.” in which we recognize and honor guests who exemplify the 4-H values of leadership and community service. 

This year, Hawaiʻi 4-H was fortunate to have as our guest State Senator Lynn DeCoite, who we thanked and honored for her support and dedication to 4-H programs, not just in her Maui County district but throughout the whole state. 

“It’s a badge of honor from each and one of you,” shared Sen. DeCoite. “I love this conference, and I love the fact that you folks have 4-H Ahaolelo …(which) means ‘to come together’ … As I learned all my life in farming and ranching, we all need to come together to make a difference.”

Past Aliʻi date back to the&

RSS
1345678910Last

Current Articles


Please edit and save settings.