Ottevalenzuela6727

The Urban Heat Island Effect (UHIE) is a widely recognised phenomenon that profoundly affects the quality of life for urban citizens. Urban greenspace can help mitigate the UHIE, but the characteristics that determine the extent to which any given greenspace can cool an urban area are not well understood. A key characteristic is likely to be the properties of trees that are found in a greenspace. Here, we explore the sensitivity of the strength of the cooling effect to tree community structure for greenspaces in Changzhou, China. Land surface temperatures were retrieved from Landsat 7 ETM+ and Landsat 8 TIRS and were used to evaluate the temperature drop amplitude (TDA) and cooling range (CR) of 15 greenspaces across each of the four seasons. Tree community structure of the greenspaces was investigated using 156 sample plots across the 15 greenspaces. We found that a number of plant community structure indicators of greenspaces have a significant impact on the strength of the cooling effect. The Shannon-Wiener diversity index, tree species richness and tree canopy coverage of greenspaces are all positively correlated with the magnitude of the temperature drop amplitude, with the strength of their influence varying seasonally. We also find that mean crown width is positively correlated with cooling range in summer and autumn, while greenspace tree density is negatively correlated with cooling range in winter. Our findings improve understanding of the relationship between plant community structure and the cooling effect of greenspaces. In particular, we highlight the important role that tree species diversity provides for mitigating the UHIE, and suggest that if planners wish to improve the role of urban greenspaces in cooling cities, they should include a higher diversity of trees species.Research on the in-situ generation of hydrogen peroxide (H2O2) using nano zero-valent iron (nZVI) has received more and more attention in recent years. However, the low utilization rate of nZVI, strict production conditions, and high energy consumption limit the application of this technology in actual environmental pollution remediation. In this study, carbon-coated nZVI (Fe0@C) was used to synthesize H2O2 in situ and realize the mineralization of nitrobenzene (NB). The results showed that the composite removed 91% of NB through adsorption, reduction, and oxidation within 120 min, of which oxidation accounts for 42.92%. Not only that, the composite material could achieve effective mineralization of NB under the wide pH range of 3-7. Quantitative experiments of hydroxyl radicals (HO) showed that the composite could generate 185.64 μM HO in 120 min without any extra energy consumption. The carbon-coated structure effectively inhibits the formation of the passivation layer on the surface of the nZVI, thereby ensuring the high activity of the Fe0. In addition, the carbon coating strengthens the sequential single-electron transfer process by changing the oxygen reduction pathway on the surface of the nZVI, so that the Fe0 can efficiently generate HO through the superoxide radical (O2-) pathway under neutral conditions. This study provides a fundamental understanding of the in-situ synthesis of H2O2 to mineralize NB by carbon-coated nZVI.Nitrate pollution of surface water has attracted global attention, and the issue is becoming increasingly significant in China. To identify the pollution status, sources, and potential non-carcinogenic health risks of nitrate in China's river water, nitrate data from 71 major rivers from 30 provinces were systematically collected. The spatial distribution of nitrate concentrations in river water was analyzed, and the main nitrate pollution sources were revealed based on the presence of nitrogen and oxygen isotopes of nitrate. The results show that approximately 7.83% of samples in China exceeded the national drinking water standard for nitrate (45 mg/L). Pomalidomide E3 ligase Ligand chemical The concentrations of nitrate in Mudan River (Linkou County), Haihe (Beijing), and Yangtze River estuary (Shanghai) exceed 90 mg/L, which indicates severe pollution. The characteristic values of δ15N and δ18O of river water in China range from -23.5‰ to 26.99‰ and - 12.7‰ to 83.5‰, indicate many sources including inorganic fertilizer, soil nitrogen, wastewater or manure. The primary sources of nitrate in river water of Northeast, Northwest, Southwest, and South China were manure, septic waste, inorganic fertilizer, and soil organic matter nitrification. Manure and septic waste were the major source of nitrate in Central, East, and North China. Correlation analysis revealed that the nitrate concentrations of surface water has a positive relationship with GDP, nitrogen fertilizer application usage, wastewater discharge, and population in China. Non-carcinogenic risk of nitrate was identified in 80% of the regions in China, and potential moderate non-carcinogenic risk areas are Shanghai, Beijing, and Shaanxi. It is urgent to solve the problem of pollution and prevent the further pollution of China's river water. Though the new "10-point Water Plan" issued by the Chinese government solved previous problems, it will take decades to control and repair polluted surface water.Monitoring data on organic pollutants published between the late 1960s and 2020 are reviewed to provide comprehensive and updated insights into their bioaccumulation characteristics, sources, and fate in snakes. Multiple organic pollutant classes including pesticides, polychlorinated biphenyls, chlorinated paraffins, dioxin-related compounds, alkanes, polycyclic aromatic hydrocarbons, flame retardants, plasticizers, etc., were detected in various aquatic and terrestrial snake species with concentrations and patterns varying between species and locations. In general, higher concentrations of organic pollutants were found in snakes collected from contaminated sites (e.g., densely populated, pesticide-treated, and waste processing areas), suggesting that snakes can serve as good biomonitors of environmental pollution caused by organic contaminants. Factors influencing concentrations and patterns of organic pollutants in snakes are discussed, providing an overview of current understanding about their accumulation, transformation, and elimination processes.