The source, characteristics and transport of viable microbial aerosols in urban centers are topics of significant environmental and public health concern. Recent studies have identified adjacent waterways, and especially polluted waterways, as an important source of microbial aerosols to urban air. The size of these aerosols influences how far they travel, their resistance to environmental stress, and their inhalation potential. In this study, we utilize a cascade impactor and aerosol particle monitor to characterize the size distribution of particles and culturable bacterial and fungal aerosols along the waterfront of a New York City embayment. We seek to address the potential contribution of bacterial aerosols from local sources and to determine how their number, size distribution, and taxonomic identity are affected by wind speed and wind direction (onshore vs. offshore). Total culturable microbial counts were higher under offshore winds (average of 778 CFU/m3 ± 67), with bacteria comprising the majority of colonies (58.5%), as compared to onshore winds (580 CFU/m3 ± 110) where fungi were dominant (87.7%). The majority of cultured bacteria and fungi sampled during both offshore winds (88%) and onshore winds (72%) were associated with coarse aerosols (>2.1 µm), indicative of production from local sources. There was a significant correlation (p < 0.05) of wind speed with both total and coarse culturable microbial aerosol concentrations. Taxonomic analysis, based on DNA sequencing, showed that Actinobacteria was the dominant phylum among aerosol isolates. In particular, Streptomyces and Bacillus, both spore forming genera that are often soil-associated, were abundant under both offshore and onshore wind conditions. Comparisons of bacterial communities present in the bioaerosol sequence libraries revealed that particle size played an important role in microbial aerosol taxonomy. Onshore and offshore coarse libraries were found to be most similar. This study demonstrates that the majority of culturable bacterial aerosols along a New York City waterfront were associated with coarse aerosol particles, highlighting the importance of local sources, and that the taxonomy of culturable aerosol bacteria differed by size fraction and wind direction.

Coastal megacities deposit significant amounts of carbon (C), nitrogen (N), and pollutants into surrounding waters. In urbanized estuaries, these inputs, including wastewater discharge and surface runoff, can affect biogeochemical cycles, microbial production, and greenhouse gas (GHG) efflux. To better understand estuarine GHG production and its connection to anthropogenic drivers, we quantified carbon dioxide (CO2) and methane (CH4) surface‐water concentrations and efflux in combination with a suite of biogeochemical parameters, including anthropogenic indicators, in the Hudson River Estuary (HRE) and adjacent waters surrounding New York, NY, over a 2‐yr period. The HRE was a source of both CO2 (33 ± 3 mmol CO2 m−2 d−1) and CH4 (177 ± 22 μmol CH4 m−2 d−1) under all measured conditions. Surface‐water salinity, oxygen saturation, fecal indicator bacteria, nitrate concentrations, and temperature best explained the variance in CO2 and CH4 concentrations in multiple regression analyses, producing robust predictive power for both GHGs. Our multifaceted data set demonstrated that CH4 and CO2 surface concentrations are explained in part by enterococci concentrations, a widely used wastewater biological indicator, explicitly linking wastewater inputs to GHG surface concentrations in the HRE. The greatest CO2 and CH4 surface‐water concentrations were found in urban tributaries and embayments, primary wastewater delivery areas throughout the HRE. Estuarine tributaries and embayments have historically received less research attention than midchannel sites, but since these shallow sites may contribute to increased GHG efflux in anthropogenically impacted estuaries, further study is warranted.

Core Ideas Carbon additions to three varied wetland soils enhanced both carbon dioxide and methane production. Methane production was negatively correlated to salinity with and without carbon additions. Microbial community representation was associated with salinity not treatment. Wetlands in close proximity to urban centers receive significant inputs of dissolved organic carbon (C) and nitrogen (N) from runoff, sewage overflow, and treated wastewater. Additions of C and N may impact greenhouse gas (GHG) production rates from temperate wetland ecosystems, which are considered a large sink for atmospheric carbon dioxide (CO2). We hypothesized that microbial activity in these anaerobic ecosystems was limited by the availability of labile C which provides electron donors to support microbial metabolism. To test this hypothesis, CO2 and methane (CH4) production rates were quantified with a series of soil incubations from three wetland sites located across a salinity gradient in the Hudson River Estuary (HRE). Acetate additions to soils enhanced CO2 (2×) and CH4 (>125×) production rates from soil slurries among all wetland soils vs. no amendment controls. Enhanced CH4 production was also inversely correlated (r2 = 0.81) to the salinity of sampled soils. In contrast, neither nitrate (NO3–) nor ammonium (NH4+) additions had a significant effect on CO2 or CH4 production rates when added alone or with acetate. Greater CO2 and CH4 production from soils with added acetate were associated with lower redox potential, increased pH, and increased hydrogen sulfide concentrations. The wetland sites had dissimilar methanogenic and sulfate reducing communities, which likely contributed to differences in CO2 and CH4 production among wetland sites. These data suggest that C loadings in wetland soils enhance both CO2 and CH4 efflux and potentially limit the capacity of wetlands impacted by anthropogenic pollution to act as C sinks.

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Se revisan y valoran los descubrimientos publicados de flora vascular devónica encontrados en España y Portugal desde el siglo XIX, la primera cita conocida se debe a Hermite (1879), hasta la actualidad. También se analizan el origen y trayectoria de los ejemplares ibéricos de flora devónica que existen actualmente en instituciones españolas y portuguesas, así como su interés paleobotánico. Por último, se resume en dos tablas las publicaciones sobre flora devónica ibérica y los ejemplares de plantas vasculares devónicas depositados en museos españoles, y se figuran todos aquellos que permanecen en las colecciones de museos españoles.