Dalrymplejeppesen1706

Further, Mn2+ behaved as a cation bridge linking both the negatively charged MnOx and humic acid, thereby increasing the stability of the MnOx nanoparticles as a result of the steric repulsion of the adsorbed humic acid. The results of this study enhance the understanding of the stability of the MnOx nanoparticles in the natural environment, as well as in water treatments.Vehicle emissions are a major contributor to air pollution in China. In this study, a high-resolution inventory of eight on-road vehicle-emitted pollutants in 53 cities within the North China Plain (NCP) was established for 152 sub-sources. Monthly emission factors were then simulated using the COPERT v5 model and their spatial distribution at 4 km × 4 km resolution was allocated based on the transportation network. In 2017, emissions of BC, CO, NH3, NMVOCs, NOx, PM10, PM2.5, and SO2 were 38.3, 2900, 21.8, 578, 2460, 113, 85.9, and 4.7 kt, respectively. These emissions and their sources differed between cities, mainly due to different vehicle populations, fleet compositions, emission share rates of different vehicle types, and emission standards in each city. Small-medium petrol passenger cars and both 20-26 t and 40-50 t heavy-duty diesel trucks of China 3 and 4 emissions standards were the main contributors for all pollutants. Higher cold-start emission factors caused higher emissions of CO, NMVOCs, NOx, and PM2.5 in winter. The cities of Beijing, Zhengzhou, Tianjin, Tangshan, Xuzhou, Qingdao, Jinan, Jining, and Zibo had the highest emission intensities. Overall, emissions decreased from the city centers toward surrounding areas. The higher contributions of heavy-duty trucks meant that higher emissions appeared along highways in a vein-like distribution. These results provide a theoretical basis for the effective prevention and control of air pollution in the NCP.Microfibers are reported as the most abundant microparticle type in the environment. Their small size and light weight allow easy and fast distribution, but also make it challenging to determine their chemical composition. Vibrational microspectroscopy methods as infrared and spontaneous Raman microscopy have been widely used for the identification of environmental microparticles. However, only few studies report on the identification of microfibers, mainly due to difficulties caused by their small diameter. Here we present the use of Stimulated Raman Scattering (SRS) microscopy for fast and reliable classification of microfibers from environmental samples. SRS microscopy features high sensitivity and has the potential to be faster than other vibrational microspectroscopy methods. As a proof of principle, we analyzed fibers extracted from the fish gastrointestinal (GIT) tract, deep-sea and coastal sediments, surface seawater and drinking water. Challenges were faced while measuring fibers from the fish GIT, due to the acidic degradation they undergo. However, the main vibrational peaks were still recognizable and sufficient to determine the natural or synthetic origin of the fibers. Notably, our results are in accordance to other recent studies showing that the majority of the analyzed environmental fibers has a natural origin. Our findings suggest that advanced spectroscopic methods must be used for estimation of the plastic fibers concentration in the environment.Invasive plants readily invade metal-contaminated areas. The hyperaccumulation of toxic heavy metals is not an uncommon feature among plant species. Although several hypotheses were proposed to explain this phenomenon, it is currently unclear how hyperaccumulation may benefit plants. The invasive Crofton weed (Ageratina adenophora) is a known hyperaccumulator of chromium and lead. We previously found that the species can also hyperaccumulate cadmium. The role of phytoaccumulation in defense to pathogen attack is unclear. We inoculated A. adenophora plants with a common generalist pathogen (Rhizoctonia solani) to test its resistance under cadmium treatment. We found evidence that cadmium hyperaccumulation reduced pathogen infection in A. adenophora. Our findings indicate elemental defense is highly cost efficient for hyperaccumulators inhabiting metal-contaminated sites, where plants were only modestly affected by cadmium. The reduction in pathogen damage conferred by cadmium was relatively high, particularly under lower cadmium levels. However, the benefits at higher levels may be capped. Elemental defense may be a key mechanism for plant invasion into polluted sites, especially in regions with widespread industrial activity. Our study highlights the importance of testing different metal concentrations when testing plant resistance and the importance of considering enemy attack when selecting plants for phytoremediation.Environmental pollution can disrupt the interactions between animals and their symbiotic bacteria, which can lead to adverse effects on the host even in the absence of direct chemical toxicity. It is therefore crucial to understand how environmental pollutants affect animal microbiomes, especially for those chemicals that are designed to target microbes. Here, we study the effects of two biocidal nanoparticles (NPs) (Ag and CuO) on the soil bacterial community and the resident gut microbiome of the earthworm Eisenia fetida over a 28-day period using metabarcoding techniques. Artenimol nmr Exposures to NPs were conducted following OECD test guidelines and effects on earthworm reproduction and juvenile biomass were additionally recorded in order to compare effects on the host to effects on microbiomes. By employing a full concentration series, we were able to link pollutants to microbiome effects in high resolution. Multivariate analysis, differential abundance analysis and species sensitivity distribution analysis showed that Ag-NPs are more toxic to soil bacteria than CuO-NPs. In contrast to the strong effects of CuO-NPs and Ag-NPs on the soil bacterial community, the earthworm gut microbiome is largely resilient to exposure to biocidal NPs. Despite this buffering effect, CuO-NPs did negatively affect the relative abundance of some earthworm symbionts, including 'Candidatus Lumbricincola'. Changes in the soil bacterial community and the earthworm microbiome occur at total copper concentrations often found or modelled to occur in agricultural fields, demonstrating that soil bacterial communities and individual taxa in the earthworm microbiome may be at risk from environmental copper exposure including in nanomaterial form.