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Estuarine submerged aquatic vegetation (SAV) provides vital habitat for macroinvertebrate communities that support diverse food webs and subsequent ecosystem services. Invasive SAV, however, has the potential to alter estuarine food webs through competition with native SAV, resulting in different associated biological communities. In the Mobile-Tensaw Delta (Alabama, USA), the invasive Eurasian milfoil, Myriophyllum spicatum, is fast becoming the dominant SAV, out-competing native SAV such as wild celery, Vallisneria americana. This study investigated the above- and belowground macroinvertebrate assemblages associated with these SAV habitats. We found significantly different assemblages between the SAV, with V. americana supporting more even and diverse epifaunal assemblages, and M. spicatum supporting greater total abundances of macroinvertebrates. Gammarid amphipods were more than 11 times more abundant in M. spicatum, while Polychaete species were threefold more abundant in V. americana. Our results suggest that V. americana may support a more diverse and even community compared to M. spicatum. If so, the continued decline in coverage of native V. americana and invasion of M. spicatum across the Mobile-Tensaw Delta could have system-wide ecological consequences. 

Abstract Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counterintuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfvén waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold,α= 2 as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed >600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: preflare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine thatα= 1.63 ± 0.03. This is below the critical threshold, suggesting that Alfvén waves are an important driver of coronal heating.