This paper takes the period from 2005 to 2022 as the examination period, and discusses the dynamic evolution law and spatial correlation characteristics of China's animal husbandry on the basis of re-measuring its carbon emissions and analyzing its current characteristics. The results show that the total amount of carbon emissions from China's animal husbandry in the study period has fluctuated, but the overall trend is declining, the carbon emission intensity has been in a continuous downward trend, only the inter-annual rate of decline is different, cattle and hog feeding is the key driver of carbon emissions from the animal husbandry. In 2022, the carbon emissions of the animal husbandry in each province and region were significantly different, and the top 10regions were mainly identified as core livestock production areas or grain production areas. The carbon emissions intensity of the animal husbandry in the interprovincial area was characterized by a distribution pattern of 'high in the northwest and low in the southeast'. The 30 provinces and regions were categorized into four types, such as those driven by cattle feeding and those driven by hog feeding, based on the composition of the carbon emissions of the animal husbandry in each region. During the study period, the carbon emission intensity of the animal husbandry as a whole, as well as that of cattle and sheep rearing, showed an obvious downward trend and the inter-provincial gap narrowed significantly; while the carbon emission intensity of hog rearing also declined, but the inter-provincial gap widened significantly. During the study period, the carbon emission intensity of China's animal husbandry has always had a significant spatial dependence, with low-low agglomeration as the main focus and high-high agglomeration as the secondary focus, and showing the characteristic of “the low is always low and the high is always high”.

This study analyzes provincial panel data from China covering the period from 2014 to 2022 to measure the level of industrial digitalization across three sectors: agriculture, industry, and services. Additionally, it accounts for the input of data factors and various undesired outputs while evaluating green total factor productivity, thereby exploring the interaction effects and mechanisms between the two. The research findings are demonstrated as follows: Significant disparities exist in the levels of industrial digitalization among provinces, demonstrating a spatial pattern of “East >Central >West.”Moreover, green total factor productivity shows a consistent upward trend, indicating a progressive improvement in regional multi-level differentiation. Robustness tests reveal that industrial digitalization across Chinese provinces significantly enhances green total factor productivity, with impact effects characterized by the order of agriculture < industry < services. Regarding transmission pathways, the development of industrial digitalization in each province predominantly boosts green total factor productivity by reducing the mismatch between capital and labor and facilitating industrial structure upgrades; In provinces characterized by high public environmental awareness and lower industrialization levels, the effect of industrial digitalization on enhancing green total factor productivity is comparatively pronounced; The impact of industrial digitalization on green total factor productivity exhibits a single threshold characteristic, contingent upon the intensity of various forms of environmental regulation, with threshold values of 0.4582 for command-and-control regulation and 0.0096 for market-based regulation. Consequently, the government should formulate differentiated regional industrial policies and marketing strategies to more effectively promote the development of industrial digitalization and bolster green total factor productivity, thereby achieving sustainable green development.

Selecting Pearl River as a typical case, over a decade of data tracking and investigation was conducted. Simulated using the analytical data as well as future scenarios of climate warming and river acidification, this study predicted the evolution of nutrient element ratios and trace metal concentrations over the next 80 years. Three significant changes in natural water bodies were suggested: firstly, insufficient carbon source allocation and nutrient accumulation leading to decreased biochemical efficiency; secondly, elevated ion exchange due to acidification, resulting in higher background concentrations of trace elements; lastly, water quality fluctuation inducing the co-release of heavy metals and toxic organic micropollutants and phase distribution shifts, forming a multi-loop feedback of pollution sources. Our study suggests that changes in aqueous solution properties of water bodies are driven by the results of simultaneous occurrence of concentration resonance and convergence effects, which are crucial factors of the physical fields. Combined pollution irreversibly changes the physicochemical properties of water bodies, resulting in a rapid fluctuation of geological background baseline values over decades. Consequently, this necessitates epochal adjustments to the evaluation of natural water body thresholds. A new emergence of water environmental challenges may include element exposure and fate changes caused by the natural evolutions, water quality structure conflicts from continuous inputs and emissions, and the approaching demands for species equity in ecological era.

In order to investigate the tolerance of endogenous partial denitrification（EPD）system to different types of low molecular weight polycyclic aromatic hydrocarbons（PAHs）and to explore methods to enhance the impact resistance of EPD systems, this study first acclimated EPD systems with 20mg/L PAHs（phenanthrene and anthracene）, and then added other types of PAHs（anthracene, phenanthrene, and naphthalene）at concentrations of 0~80mg/L to the EPD system to analyze the mechanisms of PAHs tolerance by batch tests. The results indicated that under the stress of phenanthrene and anthracene, the EPD systems maintained a high accumulation rate of 86% for NO₂^--N and a removal capacity of 50% for PO₄^3--P. In the anthracene system, the microorganisms secreted more extracellular polymeric substances to protect themselves, while a greater enrichment of PAH-RHD GNF/R and PAH-RHD GPF/R genes was observed to enhance tolerance to PAHs in the phenanthrene system. The introduction of phenanthrene and anthracene significantly enriched denitrifying glycan bacteria and denitrifying phosphorus accumulating bacteria. The denitrifying activity of the EPD system acclimated with phenanthrene was（167.429±2.321）mgN/（gVSS⋅h）, and it still maintained a well phosphorus removal capacity under the stress of naphthalene and anthracene. The EPD system acclimated with anthracene maintained high NO₂^--N accumulation capacity under the stress of naphthalene and phenanthrene, with denitrifying bacterial activity at（220.137±0.575）mgN/（gVSS⋅h）. This study provides the theoretical support for the tolerance of EPD systems to low molecular weight PAHs and also proposes insights into enhancing the impact resistance of EPS system through technological interventions, which has significant importance for optimizing the operational effectiveness of EPD in wastewater treatment.

The effects of the formation of iron minerals at the interface of birnessite（MnO₂）on the environmental behavior of antimony（Sb）were systematically studied in this paper. Many nanoparticles and abundant pore structure was found on the obtained Fe-Mn binary oxide（Fe-MnO₂）. HRTEM and XRD analysis indicated that the nanoparticles anchored on MnO₂ was ferrihydrite. The iron minerals formed on MnO₂ enhanced adsorption performance for Sb（III）and Sb（V）. The adsorption capacities of Sb（III）and Sb（V）by Fe-MnO₂ were 397.4 and 247.7mg/g, respectively, which was much higher than that of MnO₂ for Sb（III）and Sb（V）immobilization（342.0 and 71.8mg/g）. The chemical bond complexation was the dominant mechanism for Sb（III）and Sb（V）immobilization. The electrostatic adsorption played an important role in Sb（V）immobilization. The ferrihydrite made a significant contribution for reducing the mobility of Sb. MnO₂ played the critical role in the transformation of Sb（III）to Sb（V）. This study not only reveals the formation mechanism of Fe-Mn binary oxide, but also helps to further understand the migration and transformation behavior of Sb in the environment.

Taking a typical mining area as an example, statistical methods and Positive Matrix Factorization（PMF）were integrated to qualitatively and quantitatively identify key regional pollution sources and their contributors. A spatial model was further constructed, considering the spatial heterogeneity of soil heavy metal pollution and its dominant environmental drivers, with the best environmental variables and spatial scale being selected. The results revealed that the sources of soil heavy metal pollution were natural sources, exhaust gas emission sources, slag emission sources, wastewater emission sources, and transportation sources, with contributions of 8.40%, 9.55%, 1.73%, 55.37%, and 24.99% of the total pollution, respectively. Notably, atmospheric deposition（q =0.113）and soil leaching（q=0.097）were identified as the primary input and output pathways for heavy metals. Among various spatial modeling strategies, the model that integrated both spatial pollution source characteristics and environmental variables demonstrated the highest predictive accuracy, outperforming the model based solely on dominant environmental factors or pollution source characteristics. The importance of incorporating spatial information to enhance model performance was highlighted by this finding. In particular, the Geographically Weighted Regression Kriging（GWRK）model was found to achieve superior predictive accuracy（mRadius=0.2916）when multiple data sources were integrated. Overall, a scientific foundation was provided for identifying high-risk soil pollution zones in mining regions, the understanding of ecological and environmental interactions between influencing factors and heavy metal contamination was enhanced, and valuable insights were offered for spatially targeted pollution control strategies.

In this study, two paddy soils with similar organic matter contents but different iron contents were used to conduct anaerobic microcosm incubation experiments with four treatments, including Control, +NO₃^-, +As（III）, and +As（III）+NO₃^-. The transformation of arsenic, nitrogen, and iron species, as well as changes in microbial community structure and abundance were investigated in order to elucidate the effect of iron on the microbial As（III）oxidation coupling nitrate reduction processes in soils under anoxic conditions. The results revealed that As（III）oxidation was driven by nitrate reduction, and 35.3% and 43.0% of As（III）were oxidized in the soils with low iron and high iron content, respectively, at the end of incubation. The phosphate-extracted and oxalate-extracted arsenic contents were significantly higher in the soil with high iron content than those in the soil with low iron content. The presence of As（III）slowed down the nitrate reduction process, reduced the accumulation of NO₂^- and N₂O, and promoted the NH₄⁺ production. In addition, the denitrification and dissimilatory nitrate reduction to ammonium（DNRA）processes were faster in the soil with high iron content than those in the soil with low iron content. The presence of nitrate and As（III）decreased the concentrations of dissolved Fe（II）and adsorbed Fe（II）in soils, increased the concentrations of adsorbed total iron, and altered the composition and abundance of soil microbial community. Bacillus, Clostridium, and Planococcaceae were identified as the dominant bacteria during nitrate reduction and As（III）oxidation processes. This study demonstrates that soils with high content of adsorbed iron can facilitate anaerobic As（III）oxidation coupling denitrification/DNRA and enhance the immobilization of As（III）and As（V）by iron（oxyhydr）oxides in soils. These findings provide scientific basis for the regulation of arsenic transformation by iron and nitrogen elements in flooded paddy fields.

A 120-day soil incubation experiment was conducted to investigate the effects of rice husk biochar on soil properties and cadmium（Cd）immobilization in polypropylene micro-/macroplastics and Cd co-contaminated soils. The results showed that biochar addition significantly improved soil pH in the co-contaminated soils compared to the control group. It also considerably increased the content of dissolved organic carbon in soils co-contaminated by 7% plastics and Cd. In addition, biochar promoted the conversion of Cd from the active form into relatively stable form in the particulate organic matter and mineral fractions, effectively reducing both the bioavailable Cd content and the proportion of DTPA-extractable Cd（DTPA-Cd）in the co-contaminated soils. Specifically, biochar reduced the bioavailable Cd content by 7.58%~19.71% and the DTPA-Cd proportion by 20.23%~30.83% in microplastics and Cd co-contaminated soils. For macroplastics and Cd co-contaminated soils, the corresponding reductions were 23.80%~28.19%and 21.63%~22.74%, respectively. Notably, the concentration of microplastics was positively correlated with the content of bioavailable Cd, while the concentration of macroplastics showed no significant effect on it. The findings demonstrated that rice husk biochar effectively alleviated the adverse effects of the plastics and Cd co-contamination through improving soil properties, mediating the migration and transformation of Cd among soil solid fractions, as well as adsorbing and immobilizing Cd.

In this study, the degradation efficiency and mechanism of oxytetracycline（OTC）in the Fe（Ⅲ）/peracetic acid（PAA）system were investigated, and the effects of initial pH, reagents dosage and water components on OTC degradation were also explored. The results suggested that in the degradation of OTC by Fe（Ⅲ）/PAA system, Fe（Ⅲ）complexed with OTC to form Fe（Ⅲ）-OTC complex, which reduced Fe（Ⅲ）to Fe（II）through internal electron transfer. Subsequently, the generated Fe（II）catalyzed PAA to produce reactive species, thus accelerating the degradation of OTC. The results of chemical probe and radical quenching experiments showed that organic radicals（CH₃C（O）O^• and CH₃C（O）OO^•）, HO^• and Fe（IV）played major roles for the degradation of OTC in Fe（III）/PAA system. Acidic conditions were beneficial to the degradation of OTC in this system, while the removal of OTC under neutral and weakly alkaline conditions was mainly due to the PAA oxidation. The removal efficiency of OTC increased gradually with the increase of PAA or Fe（Ⅲ）dosage, but their excess concentration would inhibit OTC degradation. The presence of Cl^- and natural organic matter in Fe（Ⅲ）/PAA systeminhibited the degradation of OTC, while NO₃^-, SO₄^2- and HCO₃^- had little effect on OTC removal. The Fe（Ⅲ）/PAA system also ha d a good treatment effect on the other tetracycline pollutants.

This study investigates the adsorption and removal effects of powdered activated carbon on extracellular organic matters（EOM）from Microcystis aeruginosa（M. aeruginosa）at different growth phases and explores the removal efficiencies and adsorption mechanisms of characteristic organic components in EOM. The results indicated that the synergistic removal efficiency of organic components in M. aeruginosa EOM by powdered activated carbon was relatively low, ranging from 18.07%to 34.85%. Significant differences in adsorption efficiency were observed among different substance components, with the order of removal efficiency being microcystins>humic acids>proteins>polysaccharides. Each substance component exhibited varying proportions of easily adsorbable structures at different growth phases, leading to differences in adsorption capacity across phases. Easily adsorbable structures in polysaccharides were primarily released during the logarithmic phase, while those in proteins were predominantly secreted during the stable phase. Easily adsorbable structures in microcystins were predominantly secreted during the stable and decay phases, while the proportion of humic acid structure types showed no significant differences across phases. The adsorption process of activated carbon on M. aeruginosa EOM followed the principle of molecular-scale selective adsorption, primarily targeting low- and medium- molecular-weight substances, while exhibiting extremely poor adsorption performance for high- molecular-weight substances. This is a key factor contributing to the low removal efficiency of activated carbon for algal pollutants. This study provides significant scientific insights for the effective prevention and control of algal pollutants throughout the entire lifecycle of cyanobacterial blooms.