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841.
Gridded precipitation datasets are becoming a convenient substitute for gauge measurements in hydrological modeling; however, these data have not been fully evaluated across a range of conditions. We compared four gridded datasets (Daily Surface Weather and Climatological Summaries [DAYMET], North American Land Data Assimilation System [NLDAS], Global Land Data Assimilation System [GLDAS], and Parameter‐elevation Regressions on Independent Slopes Model [PRISM]) as precipitation data sources and evaluated how they affected hydrologic model performance when compared with a gauged dataset, Global Historical Climatology Network‐Daily (GHCN‐D). Analyses were performed for the Delaware Watershed at Perry Lake in eastern Kansas. Precipitation indices for DAYMET and PRISM precipitation closely matched GHCN‐D, whereas NLDAS and GLDAS showed weaker correlations. We also used these precipitation data as input to the Soil and Water Assessment Tool (SWAT) model that confirmed similar trends in streamflow simulation. For stations with complete data, GHCN‐D based SWAT‐simulated streamflow variability better than gridded precipitation data. During low flow periods we found PRISM performed better, whereas both DAYMET and NLDAS performed better in high flow years. Our results demonstrate that combining gridded precipitation sources with gauge‐based measurements can improve hydrologic model performance, especially for extreme events.  相似文献   
842.

Polychlorinated biphenyls (PCBs) contaminate 19% of US Superfund sites and represent a serious risk to human and environmental health. One promising strategy to remediate PCB-contaminated sediments utilizes organohalide-respiring bacteria (OHRB) that dechlorinate PCBs.

However, functional genes that act as biomarkers for PCB dechlorination processes (i.e., reductive dehalogenase genes) are poorly understood. Here, we developed anaerobic sediment microcosms that harbor an OHRB community dominated by the genus Dehalococcoides. During the 430-day microcosm incubation, Dehalococcoides 16S rRNA sequences increased two orders of magnitude to 107 copies/g of sediment, and at the same time, PCB118 decreased by as much as 70%. In addition, the OHRB community dechlorinated a range of penta- and tetra-chlorinated PCB congeners including PCBs 66, 70?+?74?+?76, 95, 90?+?101, and PCB110 without exogenous electron donor. We quantified candidate reductive dehalogenase (RDase) genes over a 430-day incubation period and found rd14, a reductive dehalogenase that belongs to Dehalococcoides mccartyi strain CG5, was enriched to 107 copies/g of sediment. At the same time, pcbA5 was enriched to only 105 copies/g of sediment. A survey for additional RDase genes revealed sequences similar to strain CG5’s rd4 and rd8. In addition to demonstrating the PCB dechlorination potential of native microbial communities in contaminated freshwater sediments, our results suggest candidate functional genes with previously unexplored potential could serve as biomarkers of PCB dechlorination processes.

  相似文献   
843.
Thomas-Walters  Laura  McNulty  Claire  Veríssimo  Diogo 《Ambio》2020,49(6):1135-1145

With the recognition that most global environmental problems are a result of human actions, there is an increasing interest in approaches which have the potential to influence human behaviour. Images have a powerful role in shaping persuasive messages, yet research on the impacts of visual representations of nature is a neglected area in biodiversity conservation. We systematically screened existing studies on the use of animal imagery in conservation, identifying 37 articles. Although there is clear evidence that images of animals can have positive effects on people’s attitudes to animals, overall there is currently a dearth of accessible and comparable published data demonstrating the efficacy of animal imagery. Most existing studies are place and context-specific, limiting the generalisable conclusions that can be drawn. Transdisciplinary research is needed to develop a robust understanding of the contextual and cultural factors that affect how animal images can be used effectively for conservation purposes.

  相似文献   
844.
Environmental Science and Pollution Research - Mg-Fe layered double hydroxide intercalated with chloride (Mg-Fe-Cl LDH) was synthetized, characterized, and evaluated as adsorbent to remove nitrate...  相似文献   
845.
Environmental Science and Pollution Research - Currently, sustainable utilization, including recycling and valorization, is becoming increasingly popular in waste management. Black soldier fly...  相似文献   
846.
Environmental Science and Pollution Research - 1,4-Dioxane is a synthetic cyclic ether traditionally used as a chlorinated solvent stabilizer. It is a small molecule and recalcitrant compound that...  相似文献   
847.

The objective of this study was to impregnate the surface of palm coconut activated carbon with nanoparticles of iron compounds using Moringa oleifera leaf extracts and pomegranate leaf by a green synthesis method and to evaluate its adsorption capacity for sodium diclofenac. The adsorbent material was characterized by zeta potential, X-ray diffraction (XRD), N2 adsorption/desorption (BET method), transmission electronic microscopy (TEM), and scanning electronic microscopy (SEM) coupled to dispersive energy spectrometry X-ray (EDX) methods. To evaluate the adsorption capacity of sodium diclofenac, the influence of pH, kinetics, isotherms, and thermodynamic properties were analysed. The impregnated adsorbents showed efficiency in the adsorption of sodium diclofenac. The kinetic model that best fit the experimental data was the pseudo-second-order model, and the equilibrium model was the Langmuir model. As for the thermodynamic study, it was verified that the adsorption reaction for all adsorbents occurs in a spontaneous, favourable way, and it is endothermic by physisorption. Therefore, this process is promising because it is a clean and non-toxic method when compared with chemical methods for the synthesis of nanoparticles.

  相似文献   
848.
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and...  相似文献   
849.
Environmental Science and Pollution Research - The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17...  相似文献   
850.
Environmental Science and Pollution Research - Exposure of geomaterials to acidic leachates may compromise their structure and functionality due to changes in physicochemical, mineralogical, and...  相似文献   
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