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The policy of "changing grain to forage" is an important means to optimize the structure of farming and breeding, a powerful measure to boost the agricultural economy, and the core of promoting high-quality development of the aquaculture industry. Based on the double difference model, panel data from eight provinces implementing the "changing grain to forage" policy was selected to explore the impact of the implementation of the "changing grain to forage" policy on the scale of livestock and poultry breeding. The research results show that the implementation of the "changing grain to forage" policy has a certain driving effect on the expansion of livestock and poultry breeding scale in China. The level of intelligent breeding and fixed asset investment has a significant promoting effect on the scale of livestock and poultry breeding. The price of calves and the intensity of disease occurrence have inhibitory effects on the scale of livestock and poultry farming. Further research has found that the implementation of the "changing grain to forage" policy can significantly promote the large-scale development of livestock and poultry in breeding farms. The level of intelligent breeding has a more significant positive effect on large-scale breeding farms. Compared to medium scale farms, the intensity of disease occurrence has a relatively small adverse impact on large-scale farms. [ABSTRACT FROM AUTHOR]

One of the most important reasons restricting the rapid development of animal husbandry in China is the shortage of protein raw materials. Urtica cannabina L. is a perennial herb rich in nutrient component and can be seen as feed to develop and utilize. The paper mainly studies the application in pigs, cattle, sheep and chicken as well as gives suggestions on the development and utilization of Urtica cannabina L., aiming to provide reference for the subsequent research and application of Urtica cannabina L. as an unconventional feed resource in livestock and poultry breeding. [ABSTRACT FROM AUTHOR]

China has a huge output of vegetables and fruits, and processed vegetable and fruit residue is rich in nutrients, rich in crude protein, crude fiber, vitamins, polyphenols, polysaccharides, flavonoids and other components, but it is not easy to preserve and has poor palatability, so it can not be directly used as animal feed. Screening of high-quality yeast and other probiotics can improve the nutritional value of vegetable and fruit residue feed and reduce feed cost, which has a positive effect on fruit and vegetable processing industry and livestock and poultry breeding industry. The paper reviewed the yeast species screening, fermentation technology and application of fermented vegetable and fruit residue in animal feed, aiming to provide reference for the research and application of fermented vegetable and fruit residue in livestock and poultry breeding. [ABSTRACT FROM AUTHOR]

As a large country of livestock and poultry breeding, China needs to timely solve the large amount of livestock and poultry manure produced every year. Composting technology, as the most widely used means of manure management, still has an influence on serious carbon and nitrogen loss, and environmental pollution. Based on the comprehensive reading of dozens of domestic and foreign literatures, this paper analyzed seven factors affecting carbon and nitrogen storage in the process of livestock manure composting, including pH value, ventilation, surface coverage, carbon nitrogen ratio, moisture, temperature, especially the types and mechanism of composting additives. It can reduce the loss of carbon and nitrogen in the composting process and environmental pollution, and improve the quality of composting through the regulation of various composting factors. [ABSTRACT FROM AUTHOR]

Reactive nitrogen (Nr) emissions aggravate air and water pollution across the world. The factors influencing Nr emissions have not been clearly uncovered, especially for regions under rapid economic growth. Here we modeled total Nr emissions in mainland China and analyzed factors driving their growth during the decade (2000–2010) of fastest socioeconomic development. Results show that total Nr emissions increased from 24.9 terrogram (Tg) to 35.2 Tg, a 41.7% increase with an average annual growth rate of 3.5%. Agricultural activities, including crop planting and livestock and poultry breeding, together took a substantial but decreasing share, from 75.2% in 2000 to 61.4% in 2010. Industrial wastewater discharge, energy use, and crop production are the three largest sources contributing to the Nr emissions growth. Factors related to scale (e.g., the amount of industrial energy use) led to a growth in Nr emissions, and factors related to efficiency (e.g., industrial energy use per unit of economic output) contributed to reduction. The decreasing effect of efficiency gains, however, was still unable to overcome the increasing effect of the activity scale. More in‐depth research studies on mitigation strategies are required, to inform the decoupling between socioeconomic development and Nr emissions. [ABSTRACT FROM AUTHOR]

The high-quality development of animal husbandry is necessary support to promote rural revitalization, and also key to building Chinese path to modernization. From perspective of connotation and era positioning, animal husbandry refers to future development of animal husbandry towards ecology, safety, and other aspects to achieve highquality and efficient development, comprehensively improve quality and quantity of social livestock and poultry product supply. Facing Chinese path to modernization, high-quality development of China's animal husbandry not only conforms to goal orientation of ecological and open cooperation in new era, but also follows Chinese law of economic and industrial layout. Therefore, it is proposed to consolidate the foundation and accelerate construction of modern livestock and poultry breeding and breeding industry. Improve security and establish an animal epidemic prevention system. Suggestions on strengthening competition and improving animal husbandry policies and measures to better play the supporting role of high-quality development of animal husbandry in process of Chinese path to modernization. [ABSTRACT FROM AUTHOR]

Guangdong Province is one of the largest agricultural regions in China, in addition to the robust economy. Agricultural development has been accelerated to ensure the food security in recent years. The agricultural non-point source pollution has been triggered by the large-scale investments in chemical fertilizers, pesticides, plastic mulch, and the rapid development of the livestock and poultry breeding industry. The purpose of this study is to unveil the emission quantity and sources of agricultural non-point source pollutants in Guangdong Province, elucidate the main characteristics and development trends of agricultural non-point source pollution, and thereby propose control measures targeting the primary pollutant sources. In this study, the emission coefficient was proposed to estimate the number of various pollutants that emitted by agriculture, livestock and poultry breeding, and aquaculture in Guangdong Province of China from 1991 to 2021. The data was also collected to better understand the agricultural development in the fertilization, arable land area, pig, cattle, poultry and aquaculture. The main causes were then determined for the agricultural non-point source pollution and their changing trends over time. The results show that: 1) An upward trend was found in the total discharges of chemical oxygen demand (COD), ammonia nitrogen (NH3 -N), total nitrogen (TN), and total phosphorus (TP) from the agricultural sources. The discharges of various pollutants decreased slightly since 2018, due to the reducing use of chemical fertilizer. The amount of fertilizer was applied per unit area more than twice the international average level. It is very necessary to reduce the chemical fertilizer use for the high efficiency. The discharges of COD, NH3 -N, TN, and TP from the agricultural sources increased to 1.9, 1.9, 1.7, and 2.2 times, respectively, in 2021, compared with 1991. 2) The primary contributors to the agricultural non-point source pollution were the planting, livestock and poultry breeding industries. The planting industry was contributed the most to the nitrogen discharges, accounting for 48% of NH3 -N losses, and 52% of total nitrogen losses from the agricultural sources, respectively. In addition, the water pollution that caused by the planting industry was mainly from the application of chemical fertilizers. The livestock and poultry breeding industry was the primary source of COD and TP discharge from the agricultural sources. Specifically, 90% and 51% of the total COD and TP discharges from agricultural sources were from the livestock and poultry breeding sector, respectively. The number of pollutants that discharged by the large-scale farming were accounted for more than 70% of the total pollutants discharged by the livestock and poultry breeding industry. Among different types of livestock and poultry, pigs were contributed the most to the emission of various pollutants, followed by poultry. Different pollutants that emitted by the aquaculture industry were accounted for between 10% and 16% of total emissions from agricultural sources. Aquaculture was ever increasing every year. Moreover, the effluent that produced by aquaculture (particularly mariculture) was challenging to clean up. Consequently, the number of pollutants that discharged into water from aquaculture sources will increase over time, indicating the increasing share of the total emissions from agricultural sources. Therefore, it is urgent to find the solutions for the waste disposal of large-scale pig farms. Also, the pollutant discharges from aquaculture needs to be considered. The finding can also provide a strong reference for the decision-making in the agricultural environment. [ABSTRACT FROM AUTHOR]

Chinese medicine is widely used in disease prevention and control, and a lot of Chinese medicine residue is produced in China every year. If these residues are not properly disposed of, they will cause damage to the environment and waste resources. The application of fermented Chinese medicine residue in the feed industry can not only alleviate the problem of feed resource shortage, but also improve the performance of livestock and poultry production. The paper reviews the fermentation process of Chinese medicine residue, the advantages of fermentation and its application in livestock and poultry production, providing reference for the resource utilization of Chinese medicine residues, reducing the cost of livestock and poultry breeding and improving the quality of livestock products. [ABSTRACT FROM AUTHOR]

The separation between planting and breeding results in an unbalanced distribution of the regional livestock and poultry manure (RLM) industry, and it has raised great concerns. A holistic analysis and problem-solving scheme using 72 townships as the research point was developed in this study. On the basis of a survey from a typical agricultural region in China, the local characteristics of manure discharge, land use, and crop cultivation were analyzed. The assessment of land carrying capacity and environmental risk assessment was conducted by simulating the nitrogen cycle. Afterwards, optimized livestock breeding strategies and inter-regional transfer and flow scheme of manure nutrients were proposed. The spatial distribution of RLM in terms of pig manure equivalent showed an imbalance of high north–south and low middle, and the nitrogen requirement of crops showed a decreasing trend from north to south. In some townships, the environmental risks were higher than level I, which indicated that pollution existed around large construction sites and water areas in the northwest. The land carrying capacity index calculated at 50% nutrient ratio displayed no overloaded risk, whereas 10–20% nutrient ratio exhibited overloaded risk. Assessments showed that the residual RLM and its nitrogen volume were 151,700 and 3574.64 tons per year, respectively. More than 80% of the study area could be used as a nitrogen nutrient sink area, and only six townships are nitrogen nutrient sources. Therefore, optimizing the allocation of manure nutrients is expected to avoid agricultural contamination from livestock manure. [ABSTRACT FROM AUTHOR]

Effective prevention and control of agricultural non-point source pollution is a major challenge faced by the Chinese local government in the context of rural revitalization, and clarifying the game relationship between stakeholders in agricultural non-point source pollution control actions will help achieve multiple co-governance better. Accordingly, this paper discusses the interactive decision-making relationships between local government and livestock and poultry breeding enterprise (LPBE) under the participation of Environmental non-government organizations (ENGOs) and public, by constructing an evolutionary game model, as well as analyzing evolutionary cooperative stability strategies and realizing the simulation of evolution processes in different scenarios by MATLAB. The results show that government subsidy has an incentive effect on LPBE to adopt the purifying strategy, yet reduces the enthusiasm of local government for supervision. Improving the participation degree and right space of ENGOs is conducive to the realization of multiple co-governance models. Furthermore, the impact of public participation on multiple co-governance of agricultural non-point source pollution is related to the local government's investigation rate and the public reporting fairness; strengthening the local government's supervision capacity and improving the public reporting fairness can achieve better collaborative governance effects. [ABSTRACT FROM AUTHOR]

Agriculture is the foundation of the national economy, and agricultural nonpoint source pollution and carbon emissions are the main environmental problems limiting the development of the agricultural economy. This study takes the Yangtze River Delta as the research object and measures agricultural carbon emissions and nonpoint source pollution in the study area from 2010 to 2020 respectively. The Tapio decoupling model is used to study types of decoupling between agricultural pollution and carbon reduction and economic growth in the Yangtze River Delta from 2010 to 2020, and the GM (1,1) model is used to predict the decoupling relationship between the agricultural environment and economic growth over the next ten years. The results show the following: (1) Agricultural COD emissions come mainly from livestock and poultry breeding, dropped from 1,130,120 tons in 2010 to 908,460 tons in 2020. Agricultural TN and TP emissions come mainly from plantations. Agricultural TN emissions dropped from 892,310 tons in 2010 to 788,020 tons in 2020. Agricultural TP emissions dropped from 149,590 tons in 2010 to130,770 tons in 2020. Agricultural carbon emissions dropped from 17,115,900 tons in 2010 to 15,786,600 tons in 2020, and come mainly from agricultural fertilizer and diesel fuel and pig breeding. (2) The decoupling effect of agricultural pollution reduction and carbon reduction in the Yangtze River Delta and economic growth has been in a long-term state, with negative decoupling occurring in a few regions, mainly in 2011, 2014 and 2020. (3) In the next ten years, except for 2021, when the coordination between agricultural pollution reduction and economic growth is poor, the two show good decoupling in the remaining years. Based on the results, this study makes recommendations on how to carry out comprehensive environmental management and promote green agricultural development. [ABSTRACT FROM AUTHOR]

Simple Summary: Kadsura coccinea was planted in large quantities in south China in recent years, and its functions and effects need to be further studied and discovered. We had previously found that Kadsura coccinea fruit extract has anti-diarrhea effects on mice, so we want to explore its influence on broiler breeding. The result showed that added 200 mg/kg Kadsura coccinea fruit extract to basic feed can replace traditional antibiotics as a growth promoter. It can improve the growth, slaughter performance, and antioxidant and regulate intestinal microorganisms of broilers, which indicated that the Kadsura coccinea fruit extract is feasible as a feed additive. This study aimed to determine whether adding Kadsura coccinea fruit extract to the diet of broilers could replace antibiotics. For this study, 300 one-day-old AA white feathered broilers were divided into five groups (no sex separated), with six repetitions per group (n = 10), as follows: blank control group (basal feed, CK group), positive drug (basal feed + 300 mg/kg aureomycin, PD group), and Kadsura coccinea low-dose, medium-dose, and high-dose groups (basal feed + 100 mg/kg, 200 mg/kg, and 300 mg/kg of Kadsura coccinea fruit extract, LD group, MD group and HD group). The experiment period was divided into early (1–21 days) and late (22–42 days) stage. We found that supplementation with Kadsura coccinea fruit extract in the diet significantly improved the growth performance of broilers (p < 0.05), reduced the feed to meat ratio (p < 0.05), reduced the fat percentage (p < 0.05), while had no significant effect on meat quality (p > 0.05) and Kadsura coccinea fruit extract could promote the development of immune organs to different extents, enhance antioxidant capacity, the contents of SOD and GSH-Px in serum were significantly increased (p < 0.05), improve the ratio of villus height to crypt depth. Finally, Kadsura coccinea fruit extract increased the relative abundance of probiotics and beneficial bacteria (Bacteroidales, NK4A214, Subdoligranulum and Eubacterium hallii) (p < 0.05) and reduced the relative abundance of harmful bacteria (Erysipelatoclostridium) (p < 0.05) in the gut of broilers. Compared with positive drug group, most of the indexes in the medium-dose group were better or had similar effects. We believe that Kadsura coccinea fruit extract can be used as a potential natural antibiotic substitute in livestock and poultry breeding programs. [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]

Manure slurry is a mixture of urine, feces, flushing water, and disinfectant in the livestock and poultry breeding industry. About two billion tons of manure slurry can be produced in China every year. Among them, the composition varies greatly, due to the complex sources. There are many influencing factors on the composition of manure slurry, such as the seasons, regions, breeding scale, fecal cleaning, and manure slurry treatment. Currently, the fixed composition value cannot accurately be calculated the amount of manure slurry, when returning to the field. Therefore, it is urgent to develop an accurate, and rapid detection system suitable for the compositions in the manure slurry on site. Fortunately, Near-Infrared (NIR) spectroscopy can offer a great potential to detect manure composition at present. Nevertheless, most reports were usually focused on the near-infrared spectrometer at the large-scale laboratory level. This kind of instrument can be confined to the application of near-infrared spectroscopy analysis in fields, due to the large bulk volume, low portability, and high price. The near-infrared spectrometer can be further developed towards the miniaturization for the technical and cost feasibility during on-site detection, particularly with the development of Micro-Electromechanical Systems (MEMS) and Micro-Opto-Electro-Mechanical Systems (MOEMS) in recent years. In addition to the need for a stable and reliable hardware system, the calibration model is another important application premise of near-infrared technology. But, there is a great challenge to establish the calibration model using cloud sharing technology. It is very necessary to access the shared resources via the various data computing services anytime, anywhere, and on-demand through the Internet. In this study, a micro NIR onsite and rapid system was proposed to detect the composition of manure slurry during field return using a calibration model under cloud sharing. A complete function was also achieved for the data acquisition, upload, prediction and storage at the same time, according to the design scheme of "micro NIR sensor + calibration model cloud sharing + Android client + mobile network". The micro NIR sensor was first used to collect the spectral data of the measured sample, then to transmit the data into the Android client through the Bluetooth protocol, and finally to the cloud server through the mobile network. A calibration model was deployed in the cloud server to calculate the received spectral data. A quantitative prediction was obtained to further send back to the Android client in real time. A rapid detection was realized for the ten parameters of manure slurry compositions, such as the Total Nitrogen (TN), Total Phosphorus (TP), Total Potassium (TK), ammonium nitrogen (NH4 +-N), nitrate nitrogen (NO3 --N), amide nitrogen (CONH2-N), Available Phosphorus (AP), Available Potassium (AK), Organic Matter (OM), and pH value. The prediction relative errors of AK, TN, AP, TP, pH, NH4 +-N, and TK in the manure slurry were less than 10%, and the rest of OM, CONH2-N, and NO3 --N were between 10%-18%. Consequently, the micro NIR technology combined with the calibration model in cloud sharing can be expected to realize the onsite, rapid and accurate detection of various compositions in the manure slurry, particularly for the full sharing of the quantitative model. Moreover, the broad market prospect can be gained for the practical application, due to the portable micro NIR sensor, the simple operation of the Android client, and the lower cost of the system. There is also no need for the professional requirements of the users in the cloud sharing of the calibration model. The finding can provide data support for the high precision return of manure slurry to the field. [ABSTRACT FROM AUTHOR]

Ammonia is the only alkaline gas in the atmosphere. Reducing ammonia emissions plays an important role in controlling atmospheric pollution. Livestock and poultry breeding industry is an important source of ammonia emissions. Scientific assessment of ammonia emissions and reduction potential in different links is of great significance. In this paper, the ammonia emission factors of different livestock and poultry breeding houses in China and abroad, the main emission reduction technologies and efficiency were summarized. Combined with the number of mechanical ventilation farms and the animal population of major livestock and poultry obtained from the second national pollution source census, the ammonia emission reduction potential of exhaust air from mechanical ventilation livestock farms in China was analyzed. The results show that the reduction potential of ammonia emission from mechanically ventilated livestock houses in China is 265.6 thousand tons; pigs, laying hens and broilers were the three main sources of livestock and poultry, and their emission reduction potential were 101.8 thousand tons, 77.3 thousand tons and 67.5 thousand tons, respectively. The emission reduction potential of the three livestock and poultry types accounted for 92.8 %. Regionally, the main implementing regions are East China, South Central and North China, with ammonia emission reduction potential accounting for 35.1%, 26.9% and 14.9%, respectively. It is proposed to carry out the construction of ammonia emission reduction facilities in mechanical ventilation barn of pig, laying hens and broiler, which can provide guarantee for the national ammonia emission reduction and the improvement of atmospheric environmental quality. [ABSTRACT FROM AUTHOR]

A large number of animal manures has been produced in China in recent years, due to the ever-increasing demand for livestock and poultry breeding. Improper disposal can pose potential environmental and health risks. Alternatively, hydrothermal carbonization has been one of the thermochemical technologies to convert the waste biomass into high value-added products without drying raw materials. Therefore, it is a highly promising potential to convert the animal manures into high value-added carbon-rich materials using hydrothermal carbonization, in order to prevent environmental pollution and pathogenic microbe spread from the random accumulation. This review aims to clarify the effects of temperature, liquid-solid ratio, reaction residence time, and additives on the yield and physicochemical properties of hydrochars, according to the main components of animal manures under hydrothermal carbonization. Some mechanisms were evaluated to determine the specific reaction pathways, including hydrolysis, dehydration, decarboxylation, aromatization, Mailard reaction, and polymerization. An interaction was also identified between various factors and reaction kinetics. Among them, the reaction temperature was the most critical factor affecting the reaction pathways and characteristics of products. A mathematical model was then established to describe the hydrothermal carbonization, further evaluating the application effect on laboratory and industrial scale. There was an increase in the temperature and residence time during hydrothermal carbonization, leading to the hydrochar with a higher carbon content and calorific value, but the yield decreased significantly. Furthermore, the volatile content of hydrochar decreased significantly after hydrothermal carbonization, which was related to the reduction of hydroxyl, and carboxyl functional groups. The heavy metals and phosphorus were often fixed in the hydrochars in more stable forms, whereas, nitrogen and potassium were transferred to the liquid products. Medium temperature (180-220 ℃) for a short time (0.5-2 h) was conducive to maintaining the nutrient elements in the hydrochar for the better capacity of soil water holding. Moreover, the hydrochar also varied in the surface functional groups and pore structure, thereby serving as the potential biofuel, adsorbent, soil amendment, and precursor of functional materials. More importantly, the addition of CaO was greatly contributed to the pH and yield of hydrochar in the process of hydrothermal carbonization, together with the improved pore structure and the number of surface functional groups. As such, the acid increased the calorific value, specific surface area, fixed carbon content, and H/C, O/C atomic ratio of hydrochar. Co-hydrothermal carbonization had avoided the weakness of hydrochar produced by a single feedstock with high ash and heavy metals content, which were possibly limited factors for the potential applications in energy materials and soil amendment. Consequently, the porous carbon materials with high specific surface area, excellent pore structure, and adjustable surface chemical properties can be widely expected to prepare in the activation and modification process with the livestock manure hydrochars as a precursor. Microwave-assisted hydrothermal carbonization of animal manures can also realize rapid heating to shorten the reaction time for the higher product yield. A further study needs to be focused on the economic feasibility and large-scale application. This finding can also provide a strong reference to promote the application potential of hydrothermal carbonization in the treatment of animal manures. [ABSTRACT FROM AUTHOR]

• Constructed an operation architecture of the coupling of energy supply and demand. • Established the comprehensive demand response mechanism based on time-sharing energy prices. • Established the minimum carbon emission cost economic scheduling model as an objective function. • The scheduling method could achieve the goal of low-carbon economic dispatch. Aiming at the problems of low energy utilization and environmental pollution in China's livestock and poultry breeding industry under the carbon peaking and carbon neutralization goals, this paper proposes an optimal scheduling model for multi-energy coupling integrated energy system with ladder-type carbon trading mechanism and demand response. First, based on the construction of a reward and punishment model with ladder-type carbon trading mechanism, this paper explores the potential interaction between the coupling ability of multiple heterogeneous energy sources and carbon emissions in consideration of the impact of carbon capture equipment on carbon emissions. Second, in view of the diversity and complexity of demands for agricultural energy supply, the energy supply side equipment model and the comprehensive demand response model of electricity, heat, and gas are established, and a low-carbon economic scheduling model of integrated agricultural energy system is proposed, aiming at minimizing the total operation cost of the system. Finally, the model is solved by CPLEX, and the coupling system of a 6-node power distribution network, a 6-node gas network, and a 4-node heat supply network is used to verify the effectiveness of the proposed model and method and optimize the operation of the integrated agricultural energy system. [ABSTRACT FROM AUTHOR]

The Dongting Lake Plain is one of the most important food production bases in China. However, the non-point source pollution has posed a great threat to social and economic development in the cultivated land, due to a large number of chemical fertilizers and pesticides that have widely been used unreasonably during agricultural production in recent years. It is also very serious for the pollution of livestock and poultry breeding. Taking 21 county-level administrative units in part of Hunan Province in the Dongting Lake Plain as the research area, the inventory analysis was made to construct three types of pollution units for the farmland fertilizer, human and livestock excrement, as well as farmland solid wastes. Some parameters were calculated, including the total emission and intensity of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP). The temporal and spatial evolution of non-point source pollution was determined in the cultivated land, further to analyze the movement trajectory of emission intensity barycenter and the degree of spatial agglomeration, using the center of gravity model and the cold/hot spot analysis. The results showed that: 1) There was a great decrease in the total emissions and emission intensity of COD, TN, and TP from the cultivated land non-point source pollution in the study area from 2005 to 2019. It was related to the promotion of ecological farming, soil testing formula technology, as well as the scale control of livestock and poultry breeding. There were also the spatial distribution characteristics of "east>west>central" in the pollution degree for three types of pollutants. 2) Three types of pollutants all moved in the longitude and latitude directions, but there was a more obvious in the east-west direction, where the barycenter of emission intensity presented a tendency to run westward. The adjustment and implementation of pollution prevention policies were attributed to the shift of the barycenter of the emission intensity in the three pollutants. 3) There were significant differences in the spatial patterns of the three pollutants. Specifically, the COD pollution was significantly different, TP was followed, and TN was the smallest in various regions. Hot spots were mostly distributed in the east of the Dongting Lake plain around the basin. The main reason was that these areas were on the edges of the intersection of the Dongting Lake and the Yangtze River, with advantageous location, rapid urbanization and industrialization, and stronger arable land utilization. The cold spots were mostly distributed in Nanxian and the surrounding areas in the middle of the Dongting Lake Plain. The concept of ecological civilization was contributed greatly to the distribution. As a result, much attention needs to pay to the treatment of non-point source pollution in the cultivated land and surrounding counties. Consequently, the non-point source pollution was improved in the cultivated land in the process of ecological civilization construction. There was also a great difference in the degree and control of cultivated land non-point source pollution in various regions. The finding can provide a sound theoretical basis to manage the non-point source pollution of cultivated land. [ABSTRACT FROM AUTHOR]

China is the world's largest livestock and poultry breeding country. Heavy metal trace element additives are widely used to prevent animal diseases and promote their growth. China produces approximately 3.8 billion tons of livestock and poultry manure annually, and untreated livestock and poultry manure causes a large amount of heavy metal elements to enter the soil environment. Currently, there is limited research on the accumulation of heavy metals in the soil due to the continuous application of livestock and poultry manure, the resulting pollution risk and the negative effects on soil ecology sustainability. This study thoroughly investigated the effects of livestock and poultry manure on the composition and function of soil microbial, and heavy metal resistance genes using 16S and metagene sequencing and 6 years of field experiments. The application of livestock and poultry manure for 6 consecutive years increased the accumulation of zinc (Zn), copper (Cu), mercury (Hg), and chromium (Cr) in the soil at the experimental sites, and cadmium (Cd) and Hg had higher potential risk levels (single potential ecological risk coefficients (E r i) of Hg and Cd were 190.49–336.52 and 385.43–468.52, respectively). Firmicutes and Zoopagomycota were significantly correlated with the soil Zn and Cd contents and pH. After continuous application of manure, the relative abundance of Hg resistance genes (merA) in soil increased by 7.3–8.2 times compared with inorganic feitilizer treatment (IF), and Cu resistance genes (copF and actP) increased by 2.45–5.45 times and 3.8–4.6 times. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt2) and metagenomic function prediction indicated that resistance genes, antioxidant response, and metal output played an important role in heavy metal bioresistance and biotransformation. This work presented heavy metal contents, microbial composition and resistance genes in continuous application of livestock and poultry manure in China, and these data will be of great use in the surveillance, maintenance, and biological removal of heavy metals in manure. [Display omitted] • Continuous application of manure, soil Cd and Hg had higher potential risk levels. • The relative abundance of soil Mortierella was increased. • Relative abundance of merA and actP was increased by 7.3–8.2 and 3.8–4.6 times. • Resistance genes, etc. played an important role in heavy metal biotransformation. [ABSTRACT FROM AUTHOR]

The rapid development of animal husbandry has resulted in serious pollution issues in the livestock and poultry breeding industry, increasing the cost of environmental management. This issue is particularly prominent in China due to its rapid economic development, significant domestic consumption, and aggressive carbon neutrality targets. This study analyses pollution emissions and spatial-temporal variation in China's cattle breeding industry. Using an emission coefficient method and panel data of 31 Chinese provinces/municipalities between 2002 and 2017, we measure the total volume of pollutant emissions from China's cattle breeding industry and five major pollutants: chemical oxygen demand, total nitrogen, total phosphorus, copper, and zinc. We also analyse the dynamic variation of the spatial distribution. The results show that both the total emissions volume and emissions of the five major pollutants have decreased to different extents, among which chemical oxygen demand has decreased the fastest. Spatial divergence is strengthened as the heavy pollution areas have moved from the southeast to the northwest of the country. This study contributes to current research by its focus on the cattle breading industry and by our improvements to the pollutant emission measurement method. • The pollutant emissions brought by cattle breeding has been significant in China. • The emissions show a decreasing trend in total. • Specific five types of major pollutant emissions are examined further. • There is a spatial transferring of emissions from the east to the northwest of China. [ABSTRACT FROM AUTHOR]