Moosrogers4046

Antibiotic resistance and rising CO2 levels are considered among the most significant challenges we will face in terms of global development over the following decades. However, the impact of elevated CO2 on soil antibiotic resistance has rarely been investigated. We used a free-air CO2 enrichment system to investigate the potential risks posed by applying mineral and organic fertilizers to paddy soil at current CO2 concentration (370 ppm) and future elevated CO2 (eCO2, 570 ppm predicted for 2100). Organic fertilizer substitution (substituting the mineral fertilizer by 50% N) alone increased the plant uptake and soil residue of sulfamethazine, and enriched sulfonamide resistance genes (sul1, sul2), tetracycline resistance genes (tetG, tetM) and class 1 integron (intl1). But it decreased the rice grain yield (by 7.6%). Comparatively, eCO2 decreased the sul2, tetG and intl1 gene abundances by organic fertilizer substitution, and meanwhile increased grain yield (by 8.4%). Proteobacteria and Nitrospirae were potential hosts of antibiotic resistance genes (ARGs). Horizontal gene transfer via intl1 may play an important role in ARGs spread under eCO2. click here Results indicated that future elevated CO2 concentration could modify the effects of organic fertilizer substitution on rice yield and soil ARGs, with unknown implications for future medicine and human health.Plutonium (Pu) has been released in Japan by two very different types of nuclear events - the 2011 Fukushima accident and the 1945 detonation of a Pu-core weapon at Nagasaki. Here we report on the use of Accelerator Mass Spectrometry (AMS) methods to distinguish the FDNPP-accident and Nagasaki-detonation Pu from worldwide fallout in soils and biota. The FDNPP-Pu was distinct in local environmental samples through the use of highly sensitive 241Pu/239Pu atom ratios. In contrast, other typically-used Pu measures (240Pu/239Pu atom ratios, activity concentrations) did not distinguish the FDNPP Pu from background in most 2016 environmental samples. Results indicate the accident contributed new Pu of ~0.4%-2% in the 0-5 cm soils, ~0.3%-3% in earthworms, and ~1%-10% in wild boar near the FDNPP. The uptake of Pu in the boar appears to be relatively uninfluenced by the glassy particle forms of fallout near the FDNPP, whereas the 134,137Cs uptake appears to be highly influenced. Near Nagasaki, the lasting legacy of Pu is greater with high percentages of Pu sourced from the 1945 detonation (~93% soils, ~88% earthworm, ~96% boar). The Pu at Nagasaki contrasts with that from the FDNPP in having proportionately higher 239Pu and was distinguished by both 240Pu/239Pu and 241Pu/239Pu atom ratios. However, compared with the contamination near the Chernobyl accident site, the Pu amounts at all study sites in Japan are orders of magnitude lower. The dose rates from Pu to organisms in the FDNPP and Nagasaki areas, as well as to human consumers of wild boar meat, have been only slightly elevated above background. Our data demonstrate the greater sensitivity of 241Pu/239Pu atom ratios in tracing Pu from nuclear releases and suggest that the Nagasaki-detonation Pu will be distinguishable in the environment for much longer than the FDNPP-accident Pu.The Yangtze River Delta (YRD) is one of the most populated and economically prosperous regions in China and contains numerous chemical industry parks. To understand the distribution and sources of polycyclic aromatic hydrocarbons (PAHs), surface water and sediment samples were collected from areas around the industrial parks. The total concentrations of 19 PAHs in water and sediment were 32.98-286 ng L-1 and 15.14-5355 ng g-1, respectively. The highest PAH concentrations in water and sediment were found in samples from Wuxi city, which were dominated by high molecular weight (HMW) PAHs, and strongly influenced by fine chemical parks. HMW compounds dominated in the sediment with PAHs containing four and five rings accounting for 61% of the sedimentary ΣPAHs, PAHs in water were dominated by low molecular weight (LMW) compounds (PAHs with two and three rings represented >68% of ΣPAHs). The results of isomeric ratio analysis and principal component analysis with multiple linear regression indicated that the PAH concentrations in water and sediment near the YRD chemical parks are strongly influenced by industrial emissions. The fugacity fraction approach was applied to explain the trend for water-sediment exchange of 16 priority PAHs, which showed that net fluxes for most were from the sediment into water. The results indicated that the LMW PAHs were in a non-steady state in the sediment-water system. An ecological risk assessment showed that most sites were low to medium risk, but one site was high risk.Meteoric 10Be and 7Be produced in the atmosphere from high-energy spallation reactions are deposited onto the Earth's surface through wet and dry deposition and are sorbed onto the surfaces of particles. On land, the sorbed concentrations scale with the residence time of sediments in a landscape-offset by slow (10Be) and fast (7Be) radioactive decay. Additionally, the amount of native 9Be, leached from minerals, correlates with the chemical weathering of soils. However, previous work has shown that chemical and physical properties of soils and river sediments affects sorption of beryllium. Therefore, the magnitude of sorbed beryllium concentrations may be more representative of the sorption capacity of the system rather than its erosional or weathering history. Although previous work has examined the physical and chemical properties of soil that influence beryllium sorption, these studies either lack consensus or exclude potentially important variables. In this work, we provide a thorough examination of variables previously reported to have influence on beryllium chemistry as well as new variables such as nitrogen, phosphorus and sulfur concentrations in order to determine which factors best predict beryllium sorption. We selected two soil endmembers with differing compositions, separated them into different size fractions, and characterized the surface area, cation exchange capacity (CEC), mineralogy, sulfur, carbon, nitrogen and phosphorus concentrations. We determined that the inverse percent abundance of quartz and the CEC best predict beryllium sorption potential in these soils. By deriving a model that relates these two variables to the percent sorbed beryllium, we were able to predict the sorption capacity of our system and reduced the error in sorbed beryllium amounts due to differences in soil properties by about 42%. From these results, we provide insight as to why there is inconsistency in the literature with regards to the physio-chemical controls on the environmental behavior of beryllium.