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In the Southern California desert, the Salton Sea is the cause of a local socioenvironmental crisis reflective of various environmental injustices. Today’s Salton Sea is fed primarily through agricultural water run-off and effluent discharge. Over 23% of the Latinx and Torres Martinez Desert Cahuilla Indian identifying residents live below the poverty line in the two zip codes north of the sea (US Census Bureau, 2021). Persistent droughts and inequitable policies have accelerated the sea’s evaporation, exacerbating environmental health problems such as poor air quality and respiratory illnesses like asthma (Farzan et al., 2019). Since 2010, nonprofit organizations such as Alianza Coachella Valley (hereafter referred to as Alianza) have been addressing these issues and campaigning for economic and environmental justice in the Eastern Coachella Valley (ECV). Prior to this work, no reliable and continuous source of water quality information was easily accessible to local communities. Most recently, Alianza championed a community science initiative with the goal of establishing ongoing environmental monitoring, research, and advocacy. Through this initiative, community members formed the Salton Sea Environmental Time Series (SSET) in 2021 with support from the American Geophysical Union’s (AGU’s) Thriving Earth Exchange program. This collaboration, along with a variety of other institutions, has fostered diversity, equity, and inclusion (DEI) within scientific academia for underrepresented ECV scholars and can serve as a blueprint for future initiatives. 

Marine snow aggregates often dominate carbon export from the surface layer to the deep ocean. Therefore, understanding the formation and properties of aggregates is essential to the study of the biological pump. Previous studies have observed a relationship between phytoplankton growth phase and the production of transparent exopolymer particles (TEP), the sticky particles secreted by phytoplankton that act as the glue during aggregate formation. In this experimental study, we aim to determine the effect of phytoplankton growth phase on properties related to aggregate settling. Cultures of the diatom Thalassiosira weissflogii were grown to four different growth phases and incubated in rotating cylindrical tanks to form aggregates. Aggregate excess density and delayed settling time through a sharp density gradient were quantified for the aggregates that were formed, and relative TEP concentration was measured for cultures before aggregate formation. Compared to the first growth phase, later phytoplankton growth phases were found to have higher relative TEP concentration and aggregates with lower excess densities and longer delayed settling times. These findings may suggest that, although particle concentrations are higher at later stages of phytoplankton blooms, aggregates may be less dense and sink slower, thus affecting carbon export.