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Rural heating is one of the main sources of carbon emissions in northern China. In this study, the“26+2”Beijing–Tianjin–Hebei air pollution transmission corridor urban agglomeration designated by the Winter Clean Heating Plan in the Northern Region (2017—2021) was used as the study area. Based on the framework of“estimating potential biomass energy-calculating alternative traditional fuel resources conversion-evaluating pollutant and carbon emission reduction effect”, the potential of biomass energy conversion and clean heating of crop straw and livestock and poultry excrement were quantitatively analyzed. Based on the panel data in 2019, the biomass energy potentials of crop straws and livestock and poultry emissions were considered. The biomass potential of these wastes indicate a reduction compared to the 6.66 million tons of standard coal or 5.5 billion m³ of natural gas, with emission reductions of approximately 0.21 million tons of pollutants (SO2, NOx) and 17.01 million tons of CO2 when fully exploited. In this study, the spatial distribution of biomass energy utilization potential of various crop straw and livestock manure in 28 prefecture-level cities (municipalities) in the study area and the effects of clean heating and emission reduction in each province were analyzed. Studies have shown that wheat and maize have the highest potential for resource utilization. The biomass energy utilization potential of the breeding industry was higher than that of planting industry, and the poultry breeding industry was the highest. The quantitative results could provide a useful reference for promoting the use of biomass energy to replace traditional fuels such as coal for clean heating in rural areas of“26 + 2”typical areas and exploring the development path from“agricultural waste”to“rural heating source”. [ABSTRACT FROM AUTHOR]

Environmental water pollution has become one of the key factors that constrain the development of urban and rural areas in China. However, the identification of high-risk priority control regions and the development of control schemes for the total amount of water pollutants still lack systematic studies. In this study, the risk prevention potential index of residents, the government, and enterprises was incorporated to construct a comprehensive water environmental risk evaluation system based on the“pressure-state-response”and to identify the risk control levels of each control unit. On this basis, a multi-objective waste load allocation model was constructed, and a water pollutant load（NH3-N）distribution scheme was constructed in Hongya County, Sichuan Province, China. The results showed that Hongchuan Town and Yuping Town, located in the lower reaches of the Qingyi River, were high-risk control units. Hongchuan Town was significantly affected by industrial wastewater discharge, while Yuping Town was jointly affected by large-scale livestock and poultry breeding, as well as industrial wastewater discharge. According to the comprehensive optimal distribution scheme, the reduction rates of ammonia nitrogen in Hongchuan Town and Yuping Town were 19.7% and 18.9%, respectively, while the total reduction rate in Hongya County was 16.3%. This study not only achieves fair and efficient reduction of water pollutants in each control unit, but also obtains a higher regional total reduction rate, which can provide a scientific reference for regional water environment management strategy formulation. [ABSTRACT FROM AUTHOR]

China has extensive livestock and poultry industries with substantial production and use of veterinary antibacterials. The longterm and massive use of veterinary antibacterials causes environmental pollution, increases bacterial resistance, and elevates safety risks for livestock, poultry, and agricultural products, further threatening human health. In this paper, we review the use of veterinary antibacterials in livestock and poultry breeding from 2009 to 2019 in China. The characteristics of the usage of veterinary antibacterials were analyzed. The findings show that the proportion of consumption of veterinary antibacterials in veterinary chemicals was 69.6%~74.1%. The utilization of veterinary antibacterials reached a maximum in 2014, and then decreased yearly. The main types of veterinary antibacterials are tetracycline, chlortetracycline, and oxytetracycline; chlortetracycline and oxytetracycline are mainly used to promote growth. Furthermore, the analysis of the antibiotics residue in different foods showed that the detection rates of antibiotics in milk, cultured fish, and vegetables were as high as 90.9%~100%. The average residue of quinolone in cultured fish was 725.13 μg·kg-1, which exceeds the national food safety limit standard (100 μg·kg-1). Additionally, we summarize the situation of antibiotic residues in the environment and the emergence and mechanism of bacterial resistance. The effects of the massive use of antibiotics on animal and human health are discussed. Ultimately, management suggestions and strategies on the prevention of antibiotics pollution are proposed in terms of source, use, emission, and remediation to help control antibiotic pollution. [ABSTRACT FROM AUTHOR]