41530 research outputs found
Sort by
Of Geese And Grass: Investigating Impacts Of Brant Grazing On Eeelgrass
Get PDFGrazing pressure is important in structuring plant communities, particularly in aquatic environments. Eelgrass (Zostera marina), a keystone species in estuaries across North America, is experiencing widespread population declines. As a keystone species, eelgrass provides numerous important functions, including: 1) water filtration, 2) sediment stabilization, 3) providing refuge and nursery habitat for numerous species, and 4) carbon sequestration. Benefits which could be lost if eelgrass beds continue to diminish. California has experienced some of the greatest eelgrass declines, and Morro Bay, CA experienced a 96% decrease in eelgrass from 2007 to 2017. Most studies to date have examined bottom-up stressors, such as sedimentation and nutrient load, but little research has been done on top-down effects. Brant geese (Branta bernicla) are specialist grazers of eelgrass, feeding voraciously on it in the winter and spring months to build energy stores for their flight to summer breeding grounds in Alaska. Simulated brant grazing studies conducted in Humboldt, CA indicate brant might play an important role in maintaining the health and productivity of eelgrass communities through selective grazing and overcompensation – where plants purportedly grow more in response to herbivory. While there has been some experimental evidence of overcompensation, the idea is not well supported overall.
Research was conducted on eelgrass beds in Morro Bay over the 2018-19 brant season. We hypothesized that: 1) brant grazing would decrease growth and overall condition of eelgrass; and 2) brant would selectively graze younger, nitrogen-rich blades. Four study sites were established, each with four open plots that allowed for natural brant grazing (treatment), and four enclosed plots that excluded brant and prevent grazing (control). Polyvinyl chloride (PVC) pipe was used to create cage-like structures around small plots of eelgrass, thus excluding brant, and exclosure effectiveness was confirmed with rigorous observations. Data on eelgrass growth and brant activity was gathered regularly at each site. We predicted that: 1) eelgrass open to brant grazing would show decreases in blade length, stipe density, and other growth and condition proxies before and after brant season when compared with eelgrass protected from brant grazing; and 2) eelgrass grazed by brant would have more epiphytes because brant selectively graze younger blades and leave older blades that accumulate more epiphytes. There were no significant differences in growth or condition of eelgrass between grazed (treatment) and ungrazed (control) plots. Brant activity was detected at each study site and brant exclosures were effective, with no evidence of brant grazing found in control plots. There was no difference in epiphyte load between grazed and ungrazed plots. The findings of this study are contrary the only previous studies examining the relationship between brant grazing and eelgrass growth. Our study suggests brant do not have a significant effect on eelgrass in Morro Bay
Development of an Undergraduate Course on Women in the Design of The Built Environment
Get PDFThe Cal Poly in San Luis Obispo (Cal Poly) Architectural Engineering (ARCE) department has seen significant progress in reaching gender equity as evidenced by recent student enrollment numbers. However, ARCE-affiliated technical and history classes still lack discussion of notable female practitioners or the value of input from women as project stakeholders. This educational shortcoming is likely true at many other civil or structural engineering, construction management, and architecture programs. To address this gap, the authors developed a new 1-credit hour course offered in Spring 2024 to Cal Poly Honors and ARCE students to expose them to the contributions and concerns of women in the architecture, engineering, and construction (AEC) fields.
In-class content has been developed which consists of engaging lectures with storytelling, case studies, and interactive group discussions while at-home assignments have students examine multimedia resources such as book excerpts, online articles, and podcast episodes. Additional activities that are planned to enrich the student experience include a panel with female leaders in AEC industry and faculty, along with a day trip to Hearst Castle to learn about the prolific California- based designer Julia Morgan.
Course deliverables range from discussion posts to reflect on course topics, creation of a podcast as the midterm project, and a final class project to produce a game and a book directed towards middle and high school students. The major course projects are intended to generate material for AEC professionals and faculty to conduct educational outreach with youth to adults from diverse backgrounds. In addition to descriptions of each of these curriculum components, this paper will summarize pre- and post-course surveys to identify the course’s impact on student awareness of women’s contributions and perspectives in the design of the built environment. Whether students are budding engineers, architecture enthusiasts, or simply curious about the stories behind buildings and civil infrastructure, this class provides a journey into the creativity, resilience, and excellence of women in the AEC domain
