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Abstract AimWe reconstructed the genetic patterns and identified the main genetic breaks of several taxa across California and Baja California coast. Additionally, we evaluated the contribution of different variables to the level of structure. LocationCalifornia and Baja California coast. TaxonFish, invertebrates, algae, seagrass and mammals. MethodsWe generated a map to reconstruct the genetic patterns using genetic information (Fst index and phylogenetic clades distribution) from a literature review of population genetics publications from 2000 to 2023. For the analysis of genetic connectivity drivers, we explored the effect of different variables representing life history traits, reproductive strategies and biogeographic variables and generated five working hypotheses which were evaluated with generalized linear models (GLMs). ResultsWe identified 42 genetic breaks from 63 species across our study area. The largest number of breaks occurs from 27° N to 29° N and from 31° N to 35° N. This range includes transition zones between ecoregions such as Punta Eugenia, Baja California, Mexico and Point Conception, California, USA. We also identified Ensenada, Baja California region as a barrier to gene flow. From a transboundary perspective, we found 40 species with connectivity between California and Baja California, including 14 commercial and or recreational species. We found none of the variables explored had a clear effect on the level of genetic differentiation of the species assessed in the region. Main ConclusionGenetic breaks among different taxa do not distribute randomly across the latitudinal range from California and Baja California coastal area, rather they are mainly located in transition zones between marine ecoregions. The challenge to identify specific variables that explain general genetic patterns highlights the complexity that drives population connectivity processes in marine species. 

Air-discharged waste from commonly used trenchless technologies of sewer pipe repairs is an emerging and poorly characterized source of urban pollution. 

Microplastic particles are of increasing environmental concern due to the widespread uncontrolled degradation of various commercial products made of plastic and their associated waste disposal. 

Iron (Fe) is ubiquitous in nature and found as Fe II or Fe III in minerals or as dissolved ions Fe 2+ or Fe 3+ in aqueous systems. The interactions of soluble Fe have important implications for fresh water and marine biogeochemical cycles, which have impacts on global terrestrial and atmospheric environments. Upon dissolution of Fe III into natural aquatic systems, organic carboxylic acids efficiently chelate Fe III to form [Fe III –carboxylate] 2+ complexes that undergo a wide range of photochemistry-induced radical reactions. The chemical composition and photochemical transformations of these mixtures are largely unknown, making it challenging to estimate their environmental impact. To investigate the photochemical process of Fe III –carboxylates at the molecular level, we conduct a comprehensive experimental study employing UV-visible spectroscopy, liquid chromatography coupled to photodiode array and high-resolution mass spectrometry detection, and oil immersion flow microscopy. In this study, aqueous solutions of Fe III –citrate were photolyzed under 365 nm light in an experimental setup with an apparent quantum yield of ( φ ) ∼0.02, followed by chemical analyses of reacted mixtures withdrawn at increment time intervals of the experiment. The apparent photochemical reaction kinetics of Fe 3+ –citrates (aq) were expressed as two generalized consecutive reactions of with the experimental rate constants of j 1 ∼ 0.12 min −1 and j 2 ∼ 0.05 min −1 , respectively. Molecular characterization results indicate that R and I consist of both water-soluble organic and Fe–organic species, while P compounds are a mixture of water-soluble and colloidal materials. The latter were identified as Fe–carbonaceous colloids formed at long photolysis times. The carbonaceous content of these colloids was identified as unsaturated organic species with low oxygen content and carbon with a reduced oxidation state, indicative of their plausible radical recombination mechanism under oxygen-deprived conditions typical for the extensively photolyzed mixtures. Based on the molecular characterization results, we discuss the comprehensive reaction mechanism of Fe III –citrate photochemistry and report on the formation of previously unexplored colloidal reaction products, which may contribute to atmospheric and terrestrial light-absorbing materials in aquatic environments.