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Although remote sensing of lake surface water temperature has been ongoing for decades and has led to important discoveries regarding the warming of lake surface temperature in some regions, the ability to access and use remote sensing data is still primarily limited to remote sensing experts. Effective use of remote sensing data involves technical skills in coding (often in multiple programming languages), application of appropriate atmospheric corrections, and integrating spatially heterogeneous remote sensing data with in situ data obtained at specific geographic locations. To improve access to remote sensing data and broaden the understanding of changes in lake surface water temperature over the past four decades, we created lakeCoSTR (lake Collection 2 Surface Temperature Retrieval), a user‐friendly, cloud‐based script that gives ecologists lacking specialized training in remote sensing the ability to access the Landsat Collection 2 temperature estimates for lakes with a surface area of at least 0.4 ha. Additionally, if in situ data are provided, a paired dataset can be created within the tool. To demonstrate lakeCoSTR, we retrieved surface water temperature data for a lake with a long monitoring history, Lake Sunapee, NH, USA, and compared long‐term surface temperature trends between data obtained via lakeCoSTR and in situ measurements. When compared with Landsat Collection 1 temperature estimates derived from a single‐channel algorithm, the Landsat Collection 2 data from lakeCoSTR required no calibration to in situ data. This suggests that lakeCoSTR can be used to document temporal trends in lakes and to reprocess analyses that relied on Collection 1 data. From 1983 until 2020, remotely sensed surface water temperature estimates at Lake Sunapee increased by 0.07–0.09°C year−1 during July and August, a trend that agreed with long‐term in situ record. As climate change continues to impact freshwater systems, a better understanding of long‐term temperature data will be vital. Remotely sensed data, like those acquired using lakeCoSTR, may provide a window into temperature trends for lakes. [ABSTRACT FROM AUTHOR]

Abstract: Airborne dust can alter ecosystem productivity and biogeochemical cycling by enhancing atmospheric nutrient and pollutant deposition. Wet dust deposition (dust‐in‐rain) is less frequently quantified than dry deposition but represents a potentially significant flux to ecosystems. We quantified dust‐in‐rain event frequency, dust influence on rainwater ionic and elemental composition, and wet dissolved and particulate deposition during weeks affected by dust‐in‐rain and all other weeks (background samples) at two sites across Texas (one arid, Guadalupe Mountains, and one humid, Gulf coastal prairie) during the centennial‐scale 2012 drought. Although dust‐in‐rain was sporadic, a clear dust signature was evident in rainwater. Compared to background samples, crustal species (Fe and Mn) were more prevalent than anthropogenic species (Cu and Zn) in dust‐in‐rain. Volume‐weighted mean rainwater concentrations of K+, Na+, and Cl− and of all particulate elements were also significantly greater in dust‐in‐rain than in background samples. In the Guadalupe Mountains, West Texas, dust‐in‐rain contributed nearly 50% of annual wet dissolved Na+ and Cl− and 22–35% of dissolved Ca2+, Mg2+, K+, and PO43− deposition. In the Gulf coastal prairie, East Texas, dust‐in‐rain delivered 19%, 13%, and 9% of annual wet dissolved PO43−, Ca2+, and K+ deposition, respectively. A major proportion of annual wet particulate deposition (>56% in Guadalupe Mountains and ~30% in Gulf coastal prairie) similarly occurred with dust‐in‐rain. Our findings show that infrequent dust‐in‐rain events constitute an important but overlooked pathway for elemental flux to ecosystems in arid source and humid receptor sites during severe drought. Quantifying these fluxes is crucial to determine dust impacts on ecosystem processes. [ABSTRACT FROM AUTHOR]

The ability to effectively exchange information and develop trusting, collaborative relationships across disciplinary boundaries is essential for 21st century scientists charged with solving complex and large‐scale societal and environmental challenges, yet these communication skills are rarely taught. Here, we describe an adaptable training program designed to increase the capacity of scientists to engage in information exchange and relationship development in team science settings. A pilot of the program, developed by a leader in ecological network science, the Global Lake Ecological Observatory Network (GLEON), indicates that the training program resulted in improvement in early career scientists’ confidence in team‐based network science collaborations within and outside of the program. Fellows in the program navigated human‐network challenges, expanded communication skills, and improved their ability to build professional relationships, all in the context of producing collaborative scientific outcomes. Here, we describe the rationale for key communication training elements and provide evidence that such training is effective in building essential team science skills. [ABSTRACT FROM AUTHOR]

Microbes in the atmosphere (microbial aerosols) play an important role in climate and provide an ecological and biogeochemical connection between oceanic, atmospheric, and terrestrial environments. However, the sources and environmental factors controlling the concentration, diversity, transport, and viability of microbial aerosols are poorly understood. This study examined culturable microbial aerosols from a coastal environment in Maine (USA) and determined the effect of onshore wind speed and fog presence on deposition rate, source, and community composition. During fog events with low onshore winds (<2ms-1) the near-shore deposition of microbial aerosols (microbial fallout) decreased with increasing wind speeds, whereas microbial fallout rates under clear conditions and comparable low wind speeds showed no wind speed dependence. Mean aerosol particle size also increased with onshore wind speed when fog was present, indicating increased shoreward transport of larger aerosol particles. 16S rRNA sequencing of culturable ocean surface bacteria and microbial aerosols deposited onshore resulted in the detection of 31 bacterial genera, with 5 dominant genera (Vibrio, Bacillus, Pseudoalteromonas, Psychrobacter, Salinibacterium) making up 66% of all sequences. The sequence library from microbial aerosol isolates, as with libraries found in other coastal/marine aerosol studies, was dominated at the phylum level by Proteobacteria, with additional representation from Firmicutes, Actinobacteria and Bacteroidetes. Seventy-five percent of the culturable microbial aerosols falling out under foggy conditions were most similar to GenBank-published sequences detected in marine environments. Using a 97% similarity cut-off, sequence libraries from ocean surface and fog isolates shared eight operational taxonomic units (OTU's) in total, three of which were the most dominant OTU's in the library, representing large fractions of the ocean (28 %) and fog (21 %) libraries. The fog and ocean surface libraries were significantly more similar in microbial community composition than clear (non-foggy) and ocean surface libraries, according to both Jaccard and Sorenson indices. These findings provide the first evidence of a difference in community composition and microbial culturability of aerosols associated with fog compared to clear conditions. The data support a dual role for fog in enhancing the fallout of viable microbial aerosols via increased gravitational settling rates and decreased aerosolization stress on the organisms, which may include relief from UV inactivation, desiccation, and oligotrophic microconditions. This study provides a strong case for ocean to terrestrial transport of microbes and a potential connection between water quality and air quality at coastal sites. [ABSTRACT FROM AUTHOR]

Microbes in the atmosphere (microbial aerosols) play an important role in climate and provide an ecological and biogeochemical connection between oceanic, atmospheric, and terrestrial environments. However, the sources and environmental factors controlling the concentration, diversity, transport, and viability of microbial aerosols are poorly understood. This study examined culturable microbial aerosols from a coastal environment in Maine (USA) and determined the effect of onshore wind speed and fog presence on deposition rate, source, and community composition. During fog events with low onshore winds (< 2 m s-1) the near-shore deposition of microbial aerosols (microbial fallout) decreased with increasing wind speeds, whereas microbial fallout rates under clear conditions and comparable low wind speeds showed no wind speed dependence. Mean aerosol particle size also increased with onshore wind speed when fog was present, indicating increased shoreward transport of larger aerosol particles. 16S rRNA sequencing of culturable ocean surface bacteria and microbial aerosols deposited onshore resulted in the detection of 31 bacterial genera, with 5 dominant genera (Vibrio, Bacillus, Pseudoalteromonas, Psychrobacter, Salinibacterium) making up 66% of all sequences. The microbial aerosol sequence library, as with libraries found in other coastal/marine aerosol studies, was dominated at the phylum level by Proteobacteria, with additional representation from Firmicutes, Actinobacteria and Bacteroidetes. Seventy-five percent of the viable microbial aerosols falling out under foggy conditions were most similar to GenBank-published sequences detected in marine environments. Using a 97% similarity cut-off, ocean surface and fog sequence libraries shared eight operational taxonomic units (OTU's) in total, three of which were the most dominant OTU's in the library, representing large fractions of the ocean (28%) and fog (21%) libraries. The fog and ocean surface libraries were significantly more similar in microbial community composition than clear (non-foggy) and ocean surface libraries, according to both Jaccard and Sorenson indices. These findings provide the first evidence of a difference in community composition and microbial viability (culturability) of aerosols associated with fog compared to clear conditions. The data support a dual role for fog in enhancing the fallout of viable (culturable) microbial aerosols via increased gravitational settling rates and decreased aerosolization stress on the organisms, which may include relief from UV inactivation, desiccation, and oligotrophic microconditions. This study provides a strong case for ocean to terrestrial transport of microbes and a potential connection between water quality and air quality at coastal sites. [ABSTRACT FROM AUTHOR]

To investigate controls on gross N transformations in forest soils, a 15N pool dilution technique was used on soils of single-species plots of five major tree species (red oak [Quercus rubra L.], sugar maple[Acersaccharum Marsh.], hemlock [Tsuga canadensis (L.) Cart], beech [Fagus grandifolia Ehrh.] and yellow birch [Betula alleghaniensis Britton]) in the Catskill Mountains of New York State. Catskill forest soils had high rates of gross mineralization and NH4+ consumption, indicating rapid NH4+ cycling, a pattern not captured by net h mineralization assays. Sugar maple had the highest rates of gross mineralization and NH4+ consumption. Rates of gross nitrification were similar to rates of net nitrification for all species. Sugar maple had the highest gross nitrification rates, while hemlock and red oak had the lowest rates. There were no significant species differences in NO3- consumption Fertilization of the plots did not significantly alter N cycling rates with the exception of yellow birch, where N fertilization decreased NO3- consumption. We observed a significant negative relationship between net nitrification and soil C/N ratio in both organic and minera horizons, but our results indicate that the mechanism underlying that relationship was different in the two horizons. In the mineral horizon, limitation of net nitrification in soils of high C/N ratio probably resulted from low gross NH4+ production. In organic horizons, low NH4+ production was not a significant factor and higher NO3- consumprion explained some of the pattern. Understanding the roles individual tree species as well as excess N input play in regulation of the N cycle will improve forest management and prediction of forest responses to elevated N deposition. [ABSTRACT FROM AUTHOR]

Flowing waters receive nitrogen (N) from the surrounding watershed and ultimately export much of this N to coastal waters, which in turn can be substantially affected by these inputs. Although the control of N export is complex, for large rivers among-system variation is predicted relatively well by simple models of human activity. Using data from 249 predominantly North Temperate watersheds that varied in size from 0.1 to over 1,000,000 km2 we examined whether these simple models lose their predictive power at smaller scales. We found that the relationship between human population density and NO3 export becomes weaker at smaller scales, and that for watersheds less than 100 km2, it explains only 8% of the 1000-fold variation in NO3 export. However, NO3 export predicted from a simple loading model related well to measured NO3 export across all scales, linear regressions of log modeled versus log measured export for small (less than 100 km2), mid-sized (100–10,000 km2), and large (more than 10,000 km2) watersheds were all highly significant (P < 0.01) and had r2 values of 0.78, 0.63, and 0.77, respectively. For the smallest systems, however, the model was biased and predicted higher NO3 export than was measured. The bias suggests slightly greater storage or gaseous N loss in smaller watersheds, whereas the light correlation between predicted and measured export indicates that for small as well as large systems, among-system variation in NO3 export is controlled primarily by anthropogenic N loads rather than site-specific variations in soil or vegetation characteristics. Across all scales, however, predictive models can be improved by the inclusion of these local parameters. [ABSTRACT FROM AUTHOR]

Climate change and other anthropogenic stressors have led to long-term changes in the thermal structure, including surface temperatures, deepwater temperatures, and vertical thermal gradients, in many lakes around the world. Though many studies highlight warming of surface water temperatures in lakes worldwide, less is known about long-term trends in full vertical thermal structure and deepwater temperatures, which have been changing less consistently in both direction and magnitude. Here, we present a globally-expansive data set of summertime in-situ vertical temperature profiles from 153 lakes, with one time series beginning as early as 1894. We also compiled lake geographic, morphometric, and water quality variables that can influence vertical thermal structure through a variety of potential mechanisms in these lakes. These long-term time series of vertical temperature profiles and corresponding lake characteristics serve as valuable data to help understand changes and drivers of lake thermal structure in a time of rapid global and ecological change., (© 2021. The Author(s).)

Bed bugs (Cimex lectularius L.) are ectoparasitic wingless insects that feed on the blood of mammals, typically in residential settings. The objectives of this study were to establish a time-course of human DNA quantitation from bed bugs and to generate human DNA profile(s) of a host and/or multiple hosts from a bed bug that fed on human blood. Female human genomic DNA concentrations ranged from 18.370 to 0.195ng/bed bug at 0-108h post blood meal (PBM), male human genomic DNA concentrations ranged from 5.4 to 0.105ng/bed bug at 0-108h PBM, and pooled human female and male blood ranged from 5.49 to 0.135ng/bed bug at 0-96h PBM. Human autosomal STR complete profiles were obtained until 72h PBM for female, male, and pooled human blood. These results reveal that identification of multiple human hosts is possible from a single bed bug. However, the ratio of each contributor may be variable depending on the amount of blood ingested from each individual and the time difference of blood consumed from each subject. Average peak heights for three STR markers of low (D3S1358), medium (D13S317), and high molecular weight (D2S1338), were also compared over time. Peak heights were consistently higher for the low molecular weight marker over all time intervals. These data suggest that some markers can be successfully recovered more than three days PBM. Hence, bed bugs can serve as physical evidence in temporal and spatial predictions to match suspects and/or victims to specific locations in criminal investigations., (Copyright © 2018 Elsevier B.V. All rights reserved.)