Spatiotemporal variations and influencing factors of methane emissions from livestock in China: A spatial econometric analysis.

In recent years, China has been implementing policies to improve the livestock industry in response to the global trend toward green and low-carbon development. These policies include the establishment of demonstration zones for high-standard agriculture, the relocation of farms to the north, etc. This study aims to investigate the impact of changes in the spatial structure of the livestock industry on methane emissions. It used panel data from 31 provinces in China from 2001 to 2021 and applied the IPCC methodology to quantify methane emissions at both the national and provincial levels. In addition, a spatial econometric model was used to analyze the impact of changes in the spatial structure of the livestock industry on methane emissions. The results show that methane from livestock in China decreased from 13.85 million tons in 2001 to 11.82 million tons in 2021. In addition, methane emissions from livestock in China show a significant spatial gradient and correlation. The Southwest has the highest methane emissions, accounting for 24 % of the total emissions. After controlling for spatial correlation and other factors in the model, it was found that the spatial structure of the livestock industry has a different influence on methane emissions both in the province and in neighboring provinces. To improve methane emission efficiency in the future, policies such as establishing functional zones for livestock farming, strengthening technological innovation and sharing for green development in agriculture, and promoting the optimization of agricultural and rural management structures should be implemented.

Beneficial Effects of Bacillus amyloliquefaciens D1 Soy Milk Supplementation on Serum Biochemical Indexes and Intestinal Health of Bearded Chickens.

This study investigated the effects of dietary supplementation with Bacillus amyloliquefaciens D1 (B. amyloliquefaciens D1) on growth performance, serum anti-inflammatory cytokines, and intestinal microbiota composition and diversity in bearded chickens. To investigate the effects of Bacillus amyloliquefaciensa and fermented soy milk, 7-day-old broilers were orally fed different doses of Bacillus amyloliquefaciens D1 fermented soy milk for 35 days, with the unfermented soy milk group as the Placebo group. This study found that B. amyloliquefaciens D1 fermented soy milk improved the intestinal microbiota of broilers, significantly increasing the abundance of beneficial bacteria and decreasing the abundance of harmful bacteria in the gut. B. amyloliquefaciens D1 fermented soy milk also significantly reduced the serum lipopolysaccharide (LPS) content. The body weight and daily weight gain of broilers were increased. In conclusion, the results of this study are promising and indicate that supplementing the diets of bearded chickens with B. amyloliquefaciens D1 fermented soy milk has many beneficial effects in terms of maintaining intestinal microbiota balance and reducing inflammation in chickens.

Isolation and Purification of Bacillus amyloliquefaciens D1 Protease and Its Application in the Fermentation of Soybean Milk to Produce Large Amounts of Free Amino Acids.

In this study, a strain of Bacillus amyloliquefaciens D1, with a notably high production of neutral protease, was isolated from Morchella crassipes. The protease was purified to 10.4-fold with a specific activity of 4542.9 U/mg and 2.7% recovery. The enzyme was purified by 70% (NH4)2SO4 and DEAE-Cellulose-52 column. The estimated molecular mass of the purified protease obtained by SDS-PAGE was approximately 40 kDa. The enzyme was optimally active at pH 6.0 and 50 °C. Furthermore, the maximum hydrolysis rate (Vmax) and apparent Michaelis-Menten constant (Km) values of the purified protease were 8.2 mg/mL and 65.7 µg/(min mL). The enzymatic properties and rapid and efficient purification of Bacillus amyloliquefaciens D1 provide the basis for its potential commercialization and industrial development. Moreover, more essential amino acids, such as isoleucine, leucine, and phenylalanine, would be released when the strain fermented soybean milk, and then a better amino acid profile would be formed in soybean milk. Results suggest that this strain exhibits great potential in fermented soybean milk, and the enzyme could lay a foundation for its industrial application and further research.

Screening and Optimization of Conditions for the Adsorption of Cd2+ in Serpentine by Using Response Surface Methodology.

In order to explore the optimal conditions for the adsorption of Cd2+ in serpentine, this paper studied the adsorption of simulated cadmium solutions with serpentine as an adsorbent. On the basis of a single factor experiment, four factors including the amount of serpentine, initial pH, the initial concentration of solutions, and adsorption time were selected as the influencing factors, and the adsorption quantity and adsorption rate of serpentine to Cd2+ were double response values using the Box-Behnken design. Response surface analyses were used to study the effects of four factors on the adsorption quantity and adsorption rate of serpentine on cadmium, and the interaction between various factors. The results showed that the optimum adsorption conditions were as follows: the amount of serpentine was 1%, the initial pH was 5.5, the initial solution concentration was 40.83 mg·L-1, and the adsorption time was 26.78 h. Under these conditions, the theoretical adsorption quantity and adsorption rate of serpentine to Cd2+ were 3.99 mg·g-1 and 95.24%, respectively. At the same time, after three repeated experiments, the actual adsorption quantity and adsorption rate of serpentine to Cd2+ were 3.91 mg·g-1 and 94.68%, respectively, and the theoretical value was similar to the actual value. Therefore, it was proved that the experimental design of the regression model is reliable, and it is feasible to use the response surface method to optimize the adsorption conditions of serpentine on Cd2+.

Kefir microbiota and metabolites stimulate intestinal mucosal immunity and its early development.

Kefir consists of a large number of probiotics, which can regulate or shape the balance of intestinal microbiota, and enhance the host's immune response. Kefir microbiota can shape the mucosal immunity of the body through SCFAs, EPS, polypeptides, lactic acid, and other metabolites and microbial antigens themselves, and this shaping may have time windows and specific pathways. Kefir can regulate antibody SIgA and IL-10 levels to maintain intestinal homeostasis, and its secreted SIgA can shape the stable microbiota system by wrapping and binding different classes of microorganisms. The incidence of intestinal inflammation is closely linked to the development and maturation of intestinal mucosal immunity. Based on summarizing the existing research results on Kefir, its metabolites, and immune system development, this paper proposes to use Kefir, traditional fermented food with natural immune-enhancing components and stable functional microbiota, as an intervention method. Early intervention in the immune system may seize the critical window period of mucosal immunity and stimulate the development and maturation of intestinal mucosal immunity in time.

Comprehensive assessment of heavy metals in soil-crop system based on PMF and evolutionary game theory.

The traditional assessment of farmland environmental quality usually focuses on soil heavy metals, but ignores agricultural produce safety. It is urgent to comprehensively assess the effects of farmland environmental quality based on soil quality and produce safety. To fill this gap, the comprehensive assessment method was improved based on previous studies, which was used to assess the pollution level of heavy metals in soil-crop system of Shenyang, Liaoning Province, Northeast China. In addition, this study also made a comprehensive analysis of pollution sources based on positive matrix factorization (PMF) model, and discussed soil-crop system income stability by evolutionary game theory. The mean concentrations of As, Cd, Cr, Hg, Pb, Cu, Zn, and Ni in soil exceeded the corresponding Shenyang soil background values (5.68 %, 14.36 %, 57.61 %, 7.86 %, 30.32 %, 5.21 %, 211.72 %, 171.88 %). The results showed that about 28.28 % of paired soil-crop points were polluted by heavy metals, especially rice-soil points. Furthermore, heavy metals in crops may be transmitted less from soil and more from other environmental media. The PMF analysis results showed that there were six pollution sources in study area, and the major contributor of pollution were agricultural activities, traffic-related activities, and industrial activities. In farmland environment protection, the only stable strategy is soil-crop system, and soil-crop system is better than the benefits of single soil or crop from the perspective of benefits. This study provides a scientific and reliable method to combine soil quality with produce safety to assess the risk of heavy metals in farmland.

Comprehensive assessment of harmful heavy metals in contaminated soil in order to score pollution level.

Soil-related problems have grown up to be a major threat to human society. Scientific evaluation is helpful to understand the status of soil pollution and provide reference to further work. In this situation, Liaoning Province, a typical industrial and agricultural province in Northeast China, was selected as a case study region. It reviewed 200 studies published between 2010 and 2020 and recorded related data of soil heavy metal. It used model method and index method to evaluate the agricultural region. The comprehensive assessment score of Liaoning pollution level was 0.8998. Dalian was 0.9536, ranking first among the 14 cities. Huludao and Jinzhou were 0.7594 respectively, ranked the last. Heavy metal accumulation in different cities stemmed from different sources, including weathering of parent materials, industrial wastes, sewage irrigation, and mining activities. In general, the pollution level of heavy metal in Liaoning was at low risk level, but it still needs to pay attention to the health risk of heavy metal and the input of heavy metal into the soil, especially cadmium (Cd). This study provides a comprehensive assessment of soil heavy metal pollution in Liaoning, while identifying policy recommendations for pollution mitigation and environmental management.

Lipopolysaccharides derived from gram-negative bacterial pool of human gut microbiota promote inflammation and obesity development.

Lipopolysaccharide (LPS) is the major component of the outer membrane of Gram-negative bacteria. It is found from intestinal microbes in the circulatory system and considered a trigger factor for low-grade inflammation in obesity. High-fat diet intake and its related obesity can cause gut microbiota disorder, leading to increased gut permeability, paracellular absorption and transcellular transport of endogenous endotoxin in the cardiovascular system. High-fat diet intake can also increase plasma LPS levels, and causing chronic or "low-grade" inflammation. In this review article, we summarize the recent research advancements on the mechanism of low-grade inflammation and its related obesity. We also propose several approaches that can be used to reduce endogenous endotoxin absorption.Supplemental data for this article is available online at https://doi.org/10.1080/08830185.2021.1996573 .

Application of ecosystem value in policy system design: A case study of Fuzhou City, China.

On the basis of exploring the replicable, popularized and demonstrative accounting model of ecosystem value, it is critically needed to solve how to reasonably apply the accounting results of ecosystem value, form the application system of ecosystem value policy system, and promote the transformation of ecosystem service value from "accounting value" to "policy point". With the accounting of Fuzhou Gross Economic Ecological Product (GEEP) and Gross Ecosystem Product (GEP) as the starting point, we screened GEEP for indicators, calculated the green gold index and GEP per unit area, and analyzed the application mode in the policy and system design. The results showed that pollutant absorption, species conservation renewal energy values, wetland severe threat area proportion, air negative oxygen ions released volume, arable land occupancy rate, marine reclamation area proportion, carbon fixation quantity, oxygen release quantity, grassland cover change rate, coast protection area and environmental degradation cost of solid waste were the indicators significantly affecting the GEEP accounting results. The green gold index of Fuzhou City in 2015 and 2018 were 1.59 and 1.23, respectively, higher than that at the whole country level. The trends of GEP per unit area followed an order of wetland ecosystem> forest ecosystem> farmland ecosystem> grassland ecosystem> marine ecosystem. Based on the influencing factors of GEEP, green gold index and GEP per unit area, the management system and mode of "entering decision-making, planning, assessment and monitoring" of ecosystem values accounting results were constructed, which would provide a theoretical basis for the formation of a long-term mechanism for promoting the construction of ecological civilization in China.

Accounting and red uction path of carbon emission firom facility agriculture in China.

Facility agriculture, a typical agricultural production management mode, could affect carbon cycle due to its unique production environmental conditions and highly intensive utilization. With the five main sources as accounting objects, including agricultural film investment, energy consumption, pesticide and fertilizer application, CO2 fertilizer application, and facility soil, we estimated the amount and intensity of carbon emission of three facility agriculture (continuous greenhouse, solar greenhouse, and plastic greenhouse) in 31 provinces in 2018. The results showed that the total carbon emission of facility agriculture in China was 210.3817 million t CO2e, with the three facility agriculture types of plastic greenhouse, solar greenhouse, and continuous greenhouse accounting for 60.2%, 37.4% and 2.4%, respectively. Carbon emission of facility agriculture was mainly contributed by soil greenhouse gas, agricultural film and supplies investment. Carbon emission per unit area of continuous greenhouses was significantly lower than that of solar and plastic greenhouses. The scientific capital allocation rate and facility agriculture scale were the two main factors influencing the carbon emission in facility agriculture. Based on all the results, we presented the carbon emission reduction path from the three perspectives of improving the scientific investment, material consumption utilization rate, and facility area utilization rate of facility agriculture.

Numerical assessment of the passivator effectiveness for Cd-contaminated soil remediation.

A highly effective, economical, and reliable remedial technology is imperative for the successful remediation of [1] cadmium (Cd)-contaminated soil. Although certain Cd passivators have been found to be effective, the methods of assessing their effectiveness are very limited and rarely studied. This study aimed to develop a practical score method for assessing the remedial effectiveness of the Cd passivator. Ultimately, 16 evaluation indexes, 36 weight coefficients, 16 utility functions, and an evaluation system set were obtained. The repair effect of passivator was analysed according to four aspects: metal pollution, soil fertility, passivator cost-effectiveness, and crop profit. The numerical score scale ranged from 0 to 1, with a higher score being indicative of higher remedial effectiveness. There were five repair levels: level 1-5. Level 1 was optimal, and level 5 the poorest. In addition, this study suggested and designed the structure of a passivator database composed of soil information, the remediation effectiveness of the passivator, and the evaluation method. This study provides more comprehensive and insightful information to guide improved soil remediation and soil contamination control.

Thermal activation of serpentine for adsorption of cadmium.

Thermal activated serpentine with high adsorption capacity for heavy metals was prepared. The batch experiment studies were conducted to evaluate the adsorption performance of Cd2+ in aqueous solution using thermal activated serpentine as adsorbent. These samples before and after adsorption were characterized by XRD, FT-IR, SEM, XPS, and N2 adsorption-desorption at low temperature. It was found that serpentine with layered structure transformed to forsterite with amorphous structure after thermal treatment at over 700°C, while the surface area of the samples was increased with activated temperature and the serpentine activated at 700°C (S-700) presented the largest surface area. The pH of solution after adsorption was increased in different degrees due to hydrolysis of MgO in serpentine, resulting in enhancing adsorption of Cd2+. The S-700 exhibited the maximum equilibrium adsorption capacity (15.21mg/g), which was 2 times more than pristine serpentine. Langmuir isotherm was proved to describe the equilibrium adsorption data better than Freundlich isotherm and pseudo second order kinetics model could fit the adsorption kinetics processes well. Based on the results of characterization with XPS and XRD, the adsorption mechanisms could be explained as primarily formation of CdCO3 and Cd(OH)2 precipitation on the surface of serpentine.

Biological toxicity of cellulose nanocrystals (CNCs) against the luxCDABE-based bioluminescent bioreporter Escherichia coli 652T7.

The aim of this study was to evaluate the biological toxicity of cellulose nanocrystals (CNCs) using the constitutively bioluminescent luxCDABE-based bioreporter Escherichia coli 652T7. The effects of CNCs on E. c oli 652T7 biotoxicity were investigated at different CNC concentrations, reaction times, and IC50 values. CNC toxicity was also compared with and without ultrasonic dispersion to establish dispersibility effects. The results demonstrated that CNCs were not significantly toxic at concentrations at or below 250 mg/L. At concentrations higher than 300 mg/L, toxicity increased linearly as CNC concentrations increased up to 2000 mg/L. IC50 calculations demonstrated an increase in cytotoxicity as CNC exposure times increased, and elevated dispersibility of the CNCs were shown to increase cytotoxicity effects. These results suggest that CNCs can impact microbial populations if elevated concentration thresholds are met.

[Risk assessment and countermeasure of BTEX in pesticide factory].

BTEX are important environmental pollutants, harmful to human through respiratory inhalation, digestive tract and skin contact, and also have teratogenic, mutagenic and carcinogenic effects. BTEX were detected in multi-media to identify their distributions and assess their human health risk in a pesticide factory in Hebei province. Purge and trap GC-MS, adsorption/thermal desorption GC chromatography and the health risk assessment model were applied, and corresponding management measures were proposed. The results showed that BTEX existed in soil, dust, air, groundwater and wastewater. The concentration of BTEX in dust of the production area was 7.33 mg x kg(-1), in particular the concentration of toluene was 5.64 mg x kg(-1), exceeding the Canadian industrial land standard. Building three scenarios for working more than 10 years, 20 years and 30 years, the total non-carcinogens index was 4.19 x10(-3), 8.25 x 10(-3) and 1.22 x 10(-2), respectively, all lower than 1; the carcinogens index of benzene was 1.70 x 10(-7), 3.34 x 10(-7) and 4.92 x 10(-7), respectively, all lower than 10(-6). It indicated that there was no significant non-carcinogens and carcinogens hazard to workers inside the factory, but they might be exposed to more health risks if their work experience increase. Finally, recommendations for improving the environmental quality and personnel security in the factory were proposed based on the research results.

[Temporal variation of water quality and driving factors in Yanghe watershed of Zhangjiakou].

Yanghe is an important water source for Guanting Reservoir, which once supplied the Beijing city with drinking water, industrial process water and water-use in landscape. Based on the data of water quality monitored by Yanghe watershed monitoring stations from 1992 to 2009, 11 pollutants were selected for analysis. The trends of changes in water quality were figured out, and the major pollutants and driving factors were measured by the integrated standard index and grey correlation analytical methods. The results showed that there were two stages of water quality change in Yanghe watershed of Zhangjiakou. Firstly, the water was polluted seriously but recovered rapidly from 1992 to 1996. Secondly, although light pollution occurred in the watershed from 1997 to 2009, the pollution factors were still above the limits. The main pollution factors are ammonia nitrogen, petroleum, permanganate index, BOD5, Cr6+ and Cd. The main driving factor of water quality is the change of land use type, and the agricultural land showed less impact on water quality than the industrial land.

[Effects of long-term localized fertilization on soil humus combining form in sheltered vegetable field].

The study showed that on a sheltered vegetable field, a long-term application of organic plus chemical fertilizers induced a higher content of loosely combined soil humus than applying chemical fertilizers alone, while there was no significant difference in firmly combined humus content among different fertilization treatments. More tightly combined humus was observed in organic fertilizer treatments than in chemical fertilizer treatments, and the highest content (11.53 g x kg(-1)) was in the treatment of organic fertilizer plus chemical NPK. The ratio of loosely/tightly combined humus tended to decrease after a long-term application of organic fertilizer, being the lowest (1.10) in the treatment of organic fertilizer plus chemical NPK.