The rapid expansion of spent lithium-ion battery (LIB) recycling has led to the generation of saline, organic-rich discharging wastewater, raising urgent demands for effective treatment. This study investigated the performance of the membrane bioreactor (MBR) in treating such wastewater, focusing on the effects of salinity stress on pollutant removal, membrane fouling, and microbial community dynamics. Results showed that increased salinity initially inhibited COD and NH4+-N removal, but the system recovered through acclimation and achieved high removal efficiencies of 90.74 % and 99.23 % at 1.3 % salinity, respectively. At low salinity levels (0.1 %- 0.6 %), transmembrane pressure (TMP) gradually increased, leading to severe membrane fouling. In contrast, at higher salinity (0.9 %-1.3 %), TMP remained stable with negligible fouling observed. Sludge characterization revealed that smaller flocs under low salinity contributed to pore clogging. Microbial analysis showed that salinity stress reduced species richness and promoted the enrichment of salt-tolerant taxa. Methyloversatilis, capable of degrading methylated compounds under saline conditions, became the dominant functional genus in later stages. Additionally, Pseudonocardia, a filamentous bacterium, gradually accumulated and likely enhanced sludge granulation, which may have contributed to fouling mitigation. These findings clarify the adaptive mechanisms of MBRs under high salinity and demonstrate their potential for treating complex LIB discharging wastewater.

Microplastics (MPs) and heavy metals (HMs) commonly co-occur in marine aquaculture systems as emerging pollutants derived from feed inputs, antifouling coatings, and industrial effluents. Their accumulation can disturb microbial homeostasis and influence the dissemination of antibiotic resistance genes (ARGs). Contrary to the widely held view that these pollutants uniformly promote ARG transfer, recent evidence indicates that they may also suppress ARG propagation under specific conditions.Although MPs and HMs are often considered synergistic drivers of ARG transfer through oxidative stress and biofilm formation, reported effects vary with particle size, polymer aging, metal type, exposure duration, salinity, pH, dissolved organic matter (DOM), and experimental realism. Recent evidence indicates that MPs may also inhibit ARG propagation under high salinity, advanced aging, or near-neutral pH, when altered surface functional groups and metal complexation reduce metal bioavailability. To reconcile these divergent findings, this review proposes a threshold-dependent "counter-selection window" as a working hypothesis. This window is defined—based on a limited number of controlled laboratory and microcosm experiments—as an environmental range in which aged MPs with elevated surface O/C ratios (>0.2) and sustained ·OH radical generation form stable surface complexes with HM ions (e.g., Cu(II), Cr(VI)), thereby reducing the bioavailable metal pool and suppressing ARG horizontal transfer. Quantitative values cited in this review (e.g., pH 6–7, salinity >30‰, MP size 75–150 nm, and 21.4–42.3% HGT reduction) are drawn from these specific experimental systems and should not be interpreted as universal boundaries applicable to all marine aquaculture environments. The duration, spatial extent, and predictability of this window under diverse field conditions remain poorly constrained, and direct validation under realistic operational settings is urgently needed. We further emphasize that this inhibitory state is unstable: acidification or increased DOM may trigger metal desorption, collapse the counter-selection window, and restore ARG proliferation. However, we acknowledge that most mechanistic evidence is derived from laboratory pure-culture, freshwater, or soil studies; direct field data from marine aquaculture systems remain scarce. Therefore, the proposed counter-selection window and inhibitory effects should be interpreted as hypothesis-generating frameworks that require validation under realistic marine aquaculture conditions, considering salinity fluctuations, feed-derived organic matter, and hydrodynamic regimes. Moving beyond the conventional unidirectional co-selection narrative, this review critically evaluates the bidirectional regulation of ARG dynamics by MP–HM interactions as reported in laboratory and microcosm studies, integrates these mechanistic findings with consideration of marine aquaculture conditions, and identifies hypothesis-driven research priorities and management strategies for assessing and mitigating ecological risks associated with complex pollutant mixtures. We emphasize that all quantitative thresholds and the proposed ‘counter-selection window’ remain theoretical constructs until validated under realistic field conditions.

Microplastics (MPs) are known to promote the spread of antibiotic resistance genes (ARGs) through biofilm formation, pollutant co-selection, and enhanced horizontal gene transfer (HGT). However, emerging evidence suggests that aged microplastics (A-MPs) may, under certain conditions, exert inhibitory effects via two coupled mechanisms: radical-mediated suppression of cellular and extracellular DNA, and plasmid-level interference with replication and transfer. Photo-oxidative aging introduces oxygen-containing functional groups and enables the surface generation of environmentally persistent free radicals (EPFRs) and reactive oxygen species (ROS), especially hydroxyl radicals (•OH). These reactive intermediates can damage cell membranes, inhibit biofilm formation, and fragment extracellular DNA, reducing conjugation and transformation frequencies. Meanwhile, nanoscale or highly concentrated A-MPs can suppress plasmid replication, particularly of low-copy plasmids, and hinder donor. recipient contact through aggregation and spatial hindrance, thereby decreasing HGT efficiency. A concentration–size–replication relationship reconciles the duality of observed effects: smaller or low-dose MPs may transiently enhance permeability and uptake, whereas higher radical fluxes and aggregation shift systems toward inhibition. This review consolidates current evidence and proposes that the oxidative microenvironments associated with aged microplastics may indirectly constrain ARG dissemination, providing a new hypothesis and research direction for understanding their ecological role in antibiotic resistance dynamics.

Open-pit coal mining caused vegetation and soil degradation in the surrounding areas of mine. However, the degradation mechanisms in arid ecosystems remain unclear. Here, the vegetation dynamics, soil microbial metabolic profiles and nutrient cycling potential were investigated across native shrublands and miningdisturbed sites (6- and 12-year durations) in western Inner Mongolia. The influencing mechanism of coal mining on vegetation and soil degradation was revealed. The results indicated: (1) After mining disturbance for 6-12 years, about 7.9-16.1 % of shrubland around the mining area was converted to grassland and barren land. The fractional vegetation coverage (FVC), plant alpha-diversity, and dominant shrub species significantly decreased; (2) The soil water content (SWC), soil organic matter (SOM) and clay content significantly decreased, whereas sand particle and heavy metals accumulated. The microbial biomass C, N and P, and substrate-induced respiration (SIR) markedly decreased. The microbial metabolic quotient (qCO2) and N limitation (enzymatic vector angle) increased, while the metabolic activity (Biolog AWCD) decreased. The dominance of bacterial K-strategies increased, whereas bacterial redundancy (alpha-diversity), resilience (network topology), dispersal (RCbray index), and pathways for C and N fixation/mineralization decreased. (3) The db-RDA and PLS-PM showed that the reduction of SWC and soil clay content as key drivers reduced soil microbial activity and nutrient cycling potential, mediated SOM and available nutrient depletion, and led to vegetation degradation. These findings deepen the insights into the degradation mechanism of vegetation and soil around the mining area, and provide theoretical reference for ecological protection and restoration in arid mining areas.

The microplastic micro-interface (MPMI) in the municipal wastewater treatment system (MWTS) provides a new ecological niche for the microbiome (MGs) and potential pathogens (PPHs), facilitating both vertical and horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs) and virulence factor genes (VFGs). However, the distribution patterns and gene transfer events of PPHs, ARGs, and VFGs in MPMI remain unknown. This study examined three representative MPMIs (PET-MPMI, PE-MPMI, and PP-MPMI) colonized in the transverse gradient of MWTS using metagenomics. MGs, PPHs, ARGs, VFGs, and MGEs varied significantly across transverse gradients and horizontal interfaces. In MPMI, MGs/PPHs exhibited better connectivity and robustness (closeness centrality 19.51/21.45 and betweenness centricity 19.66/14.07), ARG hosts (mostly Escherichia coli and Salmonella enterica) demonstrated greater contig diversity and richness (6.44-7.36%), and adhesive VFGs provided superior competitive advantages. Additionally, MPMI shows a more complex and persistent coexistence pattern of MGs, ARGs, and VFGs (54.30-57.25%), increasing pathogenicity risk. MPMI accelerates the HGT of ARGs mediated by MGEs at the horizontal interface and transverse gradients through PPHs, with MGs, PPHs, MGEs, and VFGs directly influencing the alterations in ARGs within MPMI. This study developed a conceptual framework to understand MPMI gene co-occurrence and transfer across transverse gradients and interfaces, as well as the health risks of MPMI from ARG and VFG metastasis mediated by PPHs.

The municipal wastewater treatment systems (MWTSs) are the leading enrichment site of antibiotic resistance genes (ARGs), the occurrence of which in sewage and sludge significantly influences the ARGs burden of aerosols. However, the migration behavior and impact factors of ARGs in gas-liquid-solid phase are still unclear. This study collected gas (aerosol), liquid (sewage), and solid (sludge) samples from three MWTSs to explore the cross-media transport behavior of ARGs. The results showed that the main ARGs detected in the solid-gas-liquid phase were consistent, constituting the central antibiotic resistance system of MWTSs. Multidrug resistance genes dominated cross-media transmission (average relative abundance is 42.01 %). Aminocoumarin, fluoroquinolone, and aminoglycoside resistance genes (aerosolization index of 1.260, 1.329, and 1.609, respectively) were prone to migrating from the liquid to gas phase, resulting in long-distance transmission. Environmental factors (mainly temperature and wind speed), water quality index (mainly COD), and heavy metals may be the key factors affecting the trans-media migration of ARGs between the liquid, gas, and solid phase. Based on partial least squares path modeling (PLS-PM), the migration of ARGs in gas phase is primarily influenced by ARGs' aerosolization potential in liquid and solid phase, while heavy metals indirectly influences almost all categories of ARGs. Impact factors aggravated the migration of ARGs in MWTSs through co-selection pressure. This study clarified the key pathways and impact factors that form the cross-media migration behavior of ARGs, which can more specifically control ARGs pollution from different media.

In this study, Cr(VI)-contaminated soil mixed with COPR by using ferrous sulfate (FeSO4), enzyme residue (ER), and their combination under aerobic or anaerobic condition were investigated. The concentration of Cr(VI) decreased from 1498.05 to 104.63 mg kg-1 after the simultaneous addition of FeSO4 (30 %, w/w as FeSO4 & BULL;7H2O) and ER (30 %, w/w) at 45 d under the anaerobic condition with a reduction efficiency of 93.02 %, which is higher than that by single FeSO4 (72.39 %) or ER (75.47 %) under the anaerobic condition. XRD, XPS, FTIR, and fluorescence spec-troscopy were conducted to characterize soil and ER composition. Metagenomic analysis was performed to reveal the reduction mechanisms of FeSO4 and ER. The anaerobic condition with lower Eh was beneficial for Cr(VI) reduction than aerobic condition, and Eh was the main driver for the evolution of Cr(VI) reduction-related microorganisms. Moreover, the addition of ER enriched the organic matter and microbials in the soil. During the decomposition of organic matter under the anaerobic condition, organic acids were generated, leading to a decrease in pH and promot-ing the release of Cr(VI) from minerals. They also served as electron donors in Cr(VI) reduction. Additionally, the addition of excess FeSO4 stimulated the growth of iron-reducing bacteria and sulfate-reducing bacteria, facilitating to Cr(VI) reduction. Metagenomic analysis showed that Acinetobacter, related to the nemA and nfsA genes, was the dominant Cr(VI) reduction genus. Thus, the combination of FeSO4 and ER is a promising method for the remediation of Cr(VI)-contaminated soils mixed with COPR.

Low temperatures present challenges for stable wastewater treatment operations in cold regions. Low-temperature effective microorganisms (LTEM) were added as a bioaugmentation strategy at a decentralized treatment facility to improve performance. The effects of a low-temperature bioaugmentation system (LTBS) with LTEM at low temperatures (4 °C) on organic pollutant performance, microbial community changes, and the metabolic pathways of functional genes and functional enzymes were studied. To explore the bioaugmentation mechanism of LTBS based on stress response and signalling. The results showed that the start-up time of the LTBS (S2) with LTEM was shorter (8 days) and that it removed COD and NH4+-N at higher rates (87 % and 72 %, respectively) at 4 °C. LTEM effectively degraded complex macromolecular organics into small molecular organics, and decomposing sludge flocs and the changing the extracellular polymeric substances (EPS) structure removed more organics and nitrogen. LTEM and local microbial communities (nitrifying and denitrifying bacteria) improved the ability of organic matter degradation and denitrification of the LTBS and formed a core microbial community dominated by LTEM (Bacillus and Pseudomonas). Finally, based on the functional enzymes and metabolic pathways of the LTBS, a low-temperature strengthening mechanism consisting of 6 cold stress responses and signal pathways under low temperatures was formed. This study demonstrated that the LTEM-dominated LTBS could provide an engineering alternative for future decentralized wastewater treatment in cold regions.

In order to remove multiple pollutants in the sewage sludge (SS) composting facility, a novel integrated industrial-scale biological reactor based on biological trickling filtration and fungal biological filtration (BTF-FBF) was developed. This study examined bioaerosol emission, odour removal, pollutant transformation mechanism, and project investment. At an inlet flow rate of 7200 m3/h, the average removal efficiencies of hydrogen sulfide (H2S), ammonia (NH3), and volatile organic compounds (VOCs) during the steady stage were 97.2 %, 98.9 %, and 92.2 %. The BTF-FBF separates microbial phases (bacteria and fungi) of different modules. BTF removed most hydrophilic compounds, while FBF removed hydrophobic ones. Moreover, the reactor could effectively remove pathogens or opportunistic pathogens bioaerosols, such as Escherichia coli (61.9%), Salmonella sp. (85%), andAspergillus fumigatus (82.1%). The pollutant transformation mechanism of BTF-FBF was proposed. BTF-FBF annualized costs were 324,783 CNY/year at 15 years. In conclusion, BTF-FBF provides new insights into composting facility bioaerosol, odour, and pathogen emission control.

Ochrobactrum sp. XKL1, previously found to have the ability to efficiently degrade quinoline, was bioaugmented into a lab-scale A/O/O system to treat real coking wastewater. During the bioaugmentation stage, the removal of quinoline and pyridine of the O1 tank could be enhanced by 9.88% and 7.96%, respectively. High-throughput sequencing analysis indicated that the addition of XKL1 could significantly affect the alteration of microbial community structure in the sludge. In addition, the relative abundance of Ochrobactrum has demonstrated a trend of increasing first followed by decreasing with the highest abundance of 7.87% attained on the 94th day. The bioaugmentation effects lasted for about 14 days after the strains was inoculated into the reactor. Although a decrease in the relative abundance of XKL1 was observed for a rather short period of time, the bioaugmented A/O/O system has been proven to be more effective in the removal of organic pollutants than the control. Hence, the results of this study indicated that the bioaugmentation with XKL1 is a feasible operational strategy that would be able to enhance the removal of NHCs in the treatment of coking wastewater with complex composition and high organic concentrations.

Farmland-oilfield mixed areas are fragile ecosystems that require dynamic remediation to counteract the undesirable impact of energy development. Practicable assessment methods are pivotal to a fast and accurate evaluation of the in situ bioremediation process. Petroleum pollutants impose component-dependent effects on autochthonous microbiota before and after remediation. Here, the predicted functional response of soil microbiomes to petroleum pollutants was analyzed in a historically polluted farmland-oilfield mixed area from the perspective of developing a set of feasible biomarkers for immediate post-bioremediation evaluation. An array of microbial, genetic, systematic, and phenotypic biomarkers was proposed. Our results showed that the biomarkers could proxy the stage of the bioremediation multidimensionally. We argue that functional diversity should be considered together with microbial community dynamic to evaluate the restoration status of the microbial communities in petroleum-contaminated farmland-oilfield mixed environments.

异养硝化-好氧反硝化为焦化废水处理革新提供了新思路.从某焦化废水处理厂活性污泥中分离获得一株高效的异养硝化-好氧反硝化菌株HNAD4,经16S rRNA鉴定为Pseudomonas sp..分析了菌株HNAD4的硝化、反硝化以及同步硝化反硝化(SND)性能,研究了菌株对实际焦化废水的处理能力.结果表明,当菌株以柠檬酸钠为碳源、C/N为15、温度为35℃、pH为7.0时,硝化性能最优;以NO3--N和NO2--N为混合氮源时,两种氮源可同步去除,但反硝化优先利用NO3--N;以NH4+-N、NO3--N和NO2--N为混合氮源时,SND过程中利用氮源的优先顺序依次为NH4+-N、NO3--N和NO2--N;当处理实际焦化废水时,与对照组相比,投加菌株的实验组可使A/O1/O2工艺中O1池的NH4+-N去除率提高46.45％、TN去除率提高33.14％.

乌海市是中国西北干旱区主要的煤炭工业城市之一,其PM2.5浓度变化特征、输送路径及潜在源尚不清楚.基于2016-2018年乌海市PM2.5逐小时质量浓度数据,采用聚类分析法、潜在来源贡献函数(potential source contribution function,PSCF)和浓度权重轨迹分析法(concentration-weighted trajactory,CWT)等探讨乌海市PM2.5的输送路径及潜在源.结果 表明:2016-2018年乌海市PM2.5质量浓度年均值呈下降趋势,冬季PM2.5浓度最高,夏季最低.聚类分析表明西北方向路径是乌海市四季PM2.5主要的输送路径,乌海市气流在春、秋、冬三季均来自于西北长距离输送,其PM2.5平均质量浓度约97.96～151.33 μg·m-3,而在夏季短距离输送气流是主要的输送路径,其PM2.5平均质量浓度约87.11～96.88 μg·m-3.PSCF与CWT分析表明冬季PM2.5的潜在源区范围最大,主要源自库姆塔格沙漠、柴达木盆地、腾格里沙漠、巴丹吉林沙漠以及河西走廊等地区;春、秋两季PM2.5的潜在源区主要位于库姆塔格沙漠及河西走廊地区;夏季的潜在源区范围最小,主要来自河西走廊局部地区.PM2.5重污染期间,其主要路径来源于西北方向,潜在源区主要分布在青海北部与甘肃交界处、新疆东部零星地区以及乌海南部地区.这些结果说明乌海市PM2.5污染的潜在源区主要集中在西北干旱荒漠区,因此,防风固沙和减缓土地荒漠化技术的实施可有效改善乌海市和西北干旱区的空气质量.

Anaerobic co-digestion (AcoD) has been a widely accepted method to treat food waste (FW) and sewage sludge (SS). However, there is a knowledge gap regarding the key speciation transformation of nitrogen and sulfur in AcoD. Here, we explored the changes of nitrogen (N) and sulfur (S) compounds in liquid digestion and biogas, as well as the composition of microbial community structure and related metabolic functions. The results showed that H2S in the biogas was the main form of S in the early stage, and then, it was converted into SO42− and SO32−, while NH3 and NH4+ were the main forms of N during the AcoD. In addition, bacterial diversity was associated with N and S compounds; Syntrophomonas and Aminobacterium were positively correlated to H2S, NH3, NH4+ and SO32−, and Saccharibacteria_genera_incertae_sedis, Candidatus_Cloacamonas and Thermomonas were positively correlated to SO42− and NO2−. Additionally, the FAPROTAX prediction showed that the functional composition related to N and S metabolism was different from SS and inoculum after the AcoD. This study provides detailed information of conversion of N and S of the AcoD, which could lay a foundation for the subsequent regulation of the mechanism of nitrogen and sulfur compounds in the methanogenic process.

Biofloc technology (BFT) works by stimulating a microbial community of different metabolic types in order to simultaneously treat pollutants in situ while improving aquaculture. Although microalgae are important autotrophic microorganisms in aquaculture systems, their role in BFT is rarely explored. In this study, Platymonas sp. was selected as a bioaugmentation microalgae for Penaeus vannamei nursery in a BFT system. The experimental group with microalgae additions to 1 x 10(5) cell.mL(-1) every 4 days, were compared to the control group without microalgae addition based on the water quality, biofloc community structure, and enzyme activity measurements. The results showed that the bioaugmentation of Platymonas sp. reduced nitrite-nitrogen accumulation in rearing water and improved alpha diversity of bacterial communities both in shrimp intestines and in biofloc. Platymonas sp. may improve the microbiological properties of bioflocs by increasing the relative abundance of beneficial bacteria in shrimp aquaculture including Prosthecobacter, Denitromonas, Rheinheimera, Mycobacterium, Roseobacter, Phaeodactylibacter, Cellvibrio and Nannocystis, which help promote nitrification, denitrification, and formation of bioflocs. After 30-day rearing, zootechnical performances of shrimps from the experimental group were significantly higher than those of the control group, including survival rates, specific growth rates and weight gains per week of shrimp each increasing by 63.3%, 7.6% and 53.0%, respectively. Furthermore, microalgal bioaugmentation improved the hepatopancreatic antioxidant status of P. vannamei by significantly increasing the activity of the antioxidant enzymes superoxide dismutase, catalase, and peroxidase in the experimental group. Overall, the results of this study demonstrated that Platymonas sp. addition could simultaneously improving rearing environment and nursery performance for P. vannamei in a biofloc-based system, indicating the important role of microalgae on the BFT application for shrimp nursery.

The polycyclic aromatic hydrocarbons (PAHs) that accumulate during the coking wastewater treatment process are hazardous for the surrounding environment. High molecular weight (HMW) PAHs account for more than 85% of the total PAHs in coking wastewater and sludge, respectively. The degradation of total PAHs increased by 18.97% due to the increased bioavailability of PAHs, after the biosurfactant-producing bacteria Pseudomonas aeruginosa S5 was added. The toxicity of total PAHs to humans was reduced by 26.66% after inoculation with S5. The results suggest biosurfactant-producing bacteria Pseudomonas aeruginosa S5 not only increase the biodegradation of PAHs significantly, but also have a better effect on reducing the human toxicity of PAHs. Kinetic analyses show that PAHs biodegradation fits to first-order kinetics. The degradation rate constant (k) value decreases as the number of PAH rings increases, indicating that HMW PAHs are more difficult to be biodegraded than low molecular weight (LMW) PAHs. The results indicate the bioaugmentation with the biosurfactant-producing strain has significant potential and utility in remediation of PAHs-polluted sites.

Coal mining has led to serious ecological damages in arid desert region of Northwest China. However, effects of climatic factor and mining activity on vegetation dynamics and plant diversity in this region remain unknown. Wuhai City located in the arid desert region of Northwest China is an industrial city and dominated by coal mining. Based on Landsat data and field investigation in Wuhai City, we analyzed the vegetation dynamics and the relationships with climate factors, coal mining activity and ecological restoration projects from 2000 to 2019. Results showed that vegetation in Wuhai City mostly consisted of desert plants, such as Caragana microphylla , Tetraena mongolica and Achnatherum splendens . And the vegetation fractional coverage (VFC) and greenness rate of change (GRC) showed that vegetation was slightly improved during the study period. Normalized difference vegetation index (NDVI) was positively correlated with annual mean precipitation, relative humidity and annual mean temperature, indicating that these climate factors might play important roles in the improved vegetation. Vegetation coverage and plant diversity around the coal mining area were reduced by coal mining, while the implementation of ecological restoration projects improved the vegetation coverage and plant diversity. Our results suggested that vegetation in the arid desert region was mainly affected by climate factors, and the implementation of ecological restoration projects could mitigate the impacts of coal mining on vegetation and ecological environment.

Subsidence caused by underground coal mining results in soil degradation. However, little is known about bacterial community structure and its response to a 1-year-old coal mining subsidence area in arid and semiarid areas northwest China. Soil samples from 5 unexplored areas (MC, RC, YC, LC and ZC) and a 1-year-old subsidence area above a coal working face were collected and soil biogeochemical properties and bacterial community structure were determined. Results showed electrical conductivity (EC), soil water content (SWC), soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), dissolved organic carbon (DOC), available nitrogen (AN), available phosphorus (AP) and available potassium (AK) decreased with depth. The microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and the activity of β-1,4-glucosidase (BG), β-1,4-N-acetylglucosaminidase (NAG), alkaline phosphatase (PP) and catalase (CAT) were also reduced. The nutrients, BG, PP and MBC in subsidence of marginal zone of a coal working face were significantly lower than those in control, suggesting subsidence led to a loss in nutrients and a reduction in microbial biomass. High-throughput sequencing revealed that the Sphingomonas, Gemmatimonas, Pseudomonas and Gp6, involved in C and N nutrient cycles, were dominant in this region. The relative abundances of Sphingomonas, Pseudomonas and Arthrobacter were decreased in subsidence due to the nutrient leakage and microbial biomass reduction. The predicted abundances of genes for metabolisms of xenobiotics via cytochrome P450 pathways and nitrogen were low in marginal zone, while peroxidase was high, indicating low capacities of degrading for xenobiotics and polycyclic aromatic hydrocarbons (PAHs) occurred marginal zone, while resistance to hydrogen peroxide was strengthened. Redundancy analysis (RDA) revealed EC, SWC and soil depth governed bacterial community structure. Overall, subsidence caused losses in soil water, nutrients and microbial biomass, alteration of bacterial community structure, and ultimately reduced soil nutrient conversion. Therefore, the cracks in the subsidence area should be filled manually in time, especially in marginal zone.

蜈蚣草能够超累积土壤中的砷,对土壤环境中的多环芳烃也具有较好的耐受能力,是修复砷和多环芳烃复合污染的理想修复手段之一.为探究在苯并(a)芘和砷(As)单独污染和复合污染条件下的蜈蚣草对两种污染物的吸收转运,通过水培模拟实验揭示蜈蚣草体内砷与苯并(a)芘的交互作用,同时采用双光子激光共聚焦扫描显微技术检测观察苯并(a)芘在蜈蚣草中的赋存和分布.结果表明,添加苯并(a)芘使得蜈蚣草各部分总砷含量均下降.其中,叶、茎、根分别下降149.4、78.59、47.05 mg·kg-1(以DW计)(p＜0.05),叶部下降幅度最大,达到47.3％,根部及茎部含量分别下降了 40.9％和38.2％(p＜0.05).同时苯并(a)芘的添加也改变了砷在蜈蚣草体内的赋存形态,根部与叶部三价砷的比例分别下降了 3.87％、4.20％(p＜0.05),而茎部两种砷形态比例无显著变化.砷的添加促进了蜈蚣草各部分对苯并(a)芘的积累,每株根部、茎部和叶部的累积量分别增加了 4680、109.26和226.61 ng(p＜0.05),说明苯并(a)芘和砷在蜈蚣草植株中交互作用显著,砷的添加不会改变苯并(a)芘的赋存位点,但会增强蜈蚣草对于苯并(a)芘吸收,而苯并(a)芘的添加则会抑制砷的吸收,苯并(a)芘首先由蜈蚣草根部表皮细胞吸收,通过茎部的U型维管束及茎部外缘细胞转运到叶部,赋存于叶部的表皮细胞、叶脉组织及气孔细胞当中.

喹啉、吡啶等含氮杂环化合物是焦化废水中主要的难降解有机物.以喹啉、吡啶作为目标污染物,研究了筛选出的高效降解菌红球菌(Rhodococcus sp.)KDPy1对焦化废水A/O2生物处理工艺的强化作用.结果表明,与对照组相比,红球菌的添加使O1池的COD、喹啉、吡啶去除率分别增加了11.4％、17.3％、14.0％.经生物强化后,系统内微生物群落多样性增加,且有机污染物降解菌如Stenotrophomonas和Ochrobactrum等更具优势,证实了红球菌(Rhodococcus sp.)KDPy1在焦化废水处理中的巨大应用前景.