Alex Barth | Projects

Current Research

Estuarine communities and food-webs in a dynamic future.

Estuaries food-webs are upheld by production of pelagic plankton. Yet, plankton communities are subject to great variation of environmental conditions due to freshwater inputs. Variation occurs both over long-scale oscillations of dry/wet periods and over short-term, intense shifts due to events such as storms. I'm interested in how plankton communities and their predators (fish & oysters) may repspond to these increasingly chaotic swings of conditions.

Management and Analysis of Plankton Imagery Data

Plankton imaging systems offer massive potential for better understanding spatiotemporal dynamics. However, these systems also generate a large amount of data and have unique challenges with processing and analyzing the output. Thus new statistical approaches and data-processing pipelines must be developed. I am working on methodology and statistics for interpreting the nuanced data which comes from in-situ instruments. Additionally, I have created a comprehensive R package, EcotaxaTools, for wrangling and analyzing data from Ecotaxa.

See More Get EcotaxaTools

Past Research

Vertical zonation in ocean gyres

The oligotrophic ocean gyres are one of the largest habitats on Earth. While plankton in these areas can be very sparse, their community structure and population dynamics have large impacts ocean foodwebs and biogeochemical cycles. I am interested how individual traits and environmental variation influences vertical and temporal patterns in plankton community assemblage.

Community Science Plankton Imaging

Plankton imaging offers a new frontier for improving data quality and frequency for plankton monitoring programs. Collaborating with the planktoscope developers, National Phytoplankton Monitoring groups, and several fantastic undergraduate students, I am working to distribute low-cost imaging tools to community volunteer groups.

This work is funded by the USC SPARC Graduate Research Grant.

Phytoplankton Patterns on the Central California Coast

Coastal upwelling systems are eutrophic habitats which support productive, diverse assemblages of phytoplankton. However, phytoplankton abundance and community structure is extremely variable across multiple temporal scales. To fully understand ocean ecosystems, we must understand the drivers of phytoplankton community structure. In this study, my co-authors and I synthesized a dataset consisting of 10-years of phytoplankton observations. We identified local and regional forces which structure phytoplankton abundance and community composition across seasonal and interannual timescales.

Read the Paper

Other Projects

Data-Driven Graduate Student Advocacy

Graduate students are an integral part of any research university. Yet, as both students and workers they face unique challenges. For the 2022-23 academic year, I served on the GSA President's Cabinet as a data manager and analyst. In this position, I provided a quantitative analysis of graduate student issues. I constructed resources and presented results to a variety of stakeholders including University executives. As a R-geek, these projects had some fun use of web-scrapping tools, survey data analysis, and shiny programming.

See the website See the code