环境科学最新文献

{"title":"[Remediation of Antimony-polluted Soil Using Iron Sulfide-modified Biochar and Stability Assessment After Remediation].","authors":"Sen Zhang, Qing-Yu Li, Deng-Ling Jiang, Ying Cao, Cun-Fu Gao, Tian Meng, Qiang Li","doi":"10.13227/j.hjkx.202403018","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403018","url":null,"abstract":"<p><p>To investigate the remediation effects and mechanisms of iron sulfide-modified biochar （FeS-BC） on polluted soil surrounding an antimony smelting plant, soil from around a decommissioned antimony smelting plant in the Qinglong County, Guizhou Province, was used as the research subject. Through soil cultivation experiments, the effects of raw biochar （BC） and iron sulfide-modified biochar （FeS-BC） on the leaching toxicity, bioavailability, and speciation of antimony （Sb） in the soil were compared. The results showed that with an FeS∶BC mass ratio of 1∶5 and an addition rate of 7%, the average stabilization efficiency of Sb in soils with varying degrees of Sb pollution （G1-G6） reached 66.85%. FeS-BC maintained high Sb stabilization efficiency across a wide pH range （2.0-10.0）. In soils treated with a certain proportion of BC, the leaching concentration and bioavailable content of Sb fluctuated during the remediation process, decreasing by 5.89%±3.04% （1.44%-9.08%） and 20.49%±17.74% （4.83%-58.39%）, respectively, after 60 days of remediation. In contrast, FeS-BC effectively reduced the leaching concentration and bioavailable content of Sb throughout the remediation period, with reductions of 35.80%±13.80% （17.78%-55.05%） and 34.84%±2.28% （31.60%-37.64%）, respectively, after 60 days of remediation. The stabilization mechanisms of Sb in soil by FeS-BC included electrostatic attraction, ion exchange, redox reactions, complexation, and precipitation. After 14 days of remediation with BC and FeS-BC, soils with varying Sb pollution levels （G1-G6） were subjected to alternating wet and dry conditions and freeze-thaw cycles. The leachate concentration and bioavailable content of Sb in soils remediated with BC increased, indicating a certain release risk. In contrast, in soils remediated with FeS-BC, while the leachate concentration of Sb increased, the bioavailable content decreased.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2525-2536"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144022538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Characterization of Spatial Distribution and Source Analysis of Dissolved Organic Matter in the Three Gorges Reservoir Area].","authors":"Wen-Fei Mai, Jian-Rong Ma, Jing Zhang, Yong-Mei Ma","doi":"10.13227/j.hjkx.202404202","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404202","url":null,"abstract":"<p><p>Dissolved organic matter （DOM） in inland waters plays an important role in the regional and global carbon cycles. However, limited comprehensive studies are available on the spectral characterization and traceability analysis of DOM in river systems affected by crucial hydraulic projects. This study focuses on the main stream and typical tributaries within the Three Gorges Reservoir Area. Ultraviolet-visible absorption spectroscopy （UV-vis） and three-dimensional fluorescence spectroscopy （3D-EEMs）, combined with parallel factor analysis （PARAFAC）, were used to systematically investigate the spectral properties and spatial distribution patterns of DOM in the reservoir area. The findings demonstrated that the riverine DOM in the Three Gorges Reservoir Area was influenced by a combination of endogenous and terrestrial sources, where endogenous contributions were predominant. Moreover, the riverine DOM displayed a weak humification characteristic and strong autochthonous signal. Notably, DOM in the main stream exhibited a higher relative molecular weight, greater degree of carbon skeleton polymerization, and more complex structure. The FI values of the main stream and typical tributaries in the Three Gorges Reservoir Area ranged from 1.79 to 2.48 and 1.62 to 2.03, with mean values of 1.95 and 1.93, respectively. Additionally, the mean values of BIX in the main stream and tributaries were 0.92 and 0.85, respectively. The results of the FI and BIX analyses indicated that the riverine DOM of the reservoir area was driven by both endogenous and terrestrial sources, with the prevalence of endogenous sources. EEMs-PARAFAC analysis revealed that, in addition to the analogous C1 （humic-like） and C2 （tyrosine-like） fractions, DOM in the main stream also included a mixed humic-like fraction, C3. Correlation analysis revealed that the spectral characteristics of DOM in the main stream and representative tributaries in the Three Gorges Reservoir Area exhibited pronounced spatial heterogeneity and correlation because of the effects of anthropogenic disturbances, land use, and cumulative effects of the tributaries. These findings provide scientific insights for the conservation and management of aquatic ecosystems in the Three Gorges Reservoir Area.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2145-2153"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144051014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Spatio-temporal Evolution and Prediction of Carbon Storage in the Yangtze River Delta Urban Agglomeration Based on PLUS-InVEST Model].","authors":"Wei-Wu Wang, Tian-le Fu, Huan Chen","doi":"10.13227/j.hjkx.202404046","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404046","url":null,"abstract":"<p><p>Land use change is a crucial factor influencing the variation of carbon storage in terrestrial ecosystems. Studying the relationship between land use change and carbon storage is important for optimizing regional land use structure, maintaining regional carbon balance, and enhancing regional carbon storage. Against the backdrop of the \"Dual Carbon\" goals and the dual emphasis on high-quality integrated development in the region, the Yangtze River Delta （YRD） region holds a strategic position as a hub of China's modernization efforts. Therefore, taking the YRD urban agglomeration as an example, based on the PLUS model, an analysis of land use changes from 2000 to 2020 was conducted. Scenarios including natural development, farmland protection, and ecological priority were set to simulate and predict the land use pattern of the YRD urban agglomeration in 2030. Furthermore, the InVEST model was used to calculate the changes in carbon storage in the YRD urban agglomeration under different scenarios for the periods of 2000 to 2020 and 2030. Finally, spatial autocorrelation analysis was utilized to explore the spatio-temporal characteristics of carbon storage in the terrestrial ecosystems of the YRD urban agglomeration under different scenarios, and corresponding suggestions were proposed. The results indicated that： ① From 2000 to 2020, the carbon storage in the YRD urban agglomeration decreased by 51.08×10⁶ t. The reduction in farmland area （7.82%） and increase in construction land area （7.56%） were the main reasons for carbon loss. ② By 2030, the carbon storage in the terrestrial ecosystem of the YRD urban agglomeration under the scenarios of natural development, farmland protection, and ecological priority were estimated to be 2.65×10⁹, 2.67×10⁹, and 2.70×10⁹ t, respectively. Compared with the carbon storage values in 2020, the values under all three scenarios showed a decrease to varying degrees. ③ The results of local spatial autocorrelation analysis showed similar spatial distribution of carbon storage under all three scenarios. High-value areas were clustered in the southern and western regions of the YRD urban agglomeration, whereas low-value areas were concentrated in the eastern and central regions. These findings contribute substantially to achieving the \"carbon peaking and carbon neutrality\" goals in the YRD urban agglomeration.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"1937-1950"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144051189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Occurrence, Driving Factors, and Risk Assessment of Microplastics in Surface Water of Typical River Basins in the Yangtze River Delta, China].","authors":"Run-Dong Wang, Chun Hu, Chen-Xin Huang, Huzihawu Gulizila, Li-Xin Zhang, Chen-Ye Xu","doi":"10.13227/j.hjkx.202404044","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404044","url":null,"abstract":"<p><p>Rivers and lakes are important channels for the migration, transformation, and transportation of microplastics （MPs） pollution from land sources into the sea. A large number of studies have investigated the pollution characteristics of MPs in different watersheds, but little to none have considered the driving factors for spatial distribution based on network analysis. In this study, Taihu Lake, Taipu River, and Huangpu River in the Yangtze River Delta were selected as the target area. Microplastics were analyzed based on field sampling, stereomicroscopy, and Fourier transform infrared spectroscopy. According to the results, MPs were 100% detected at all sampling sites. The abundance of MPs in the surface water of Taihu Lake [（7 076±1 886） n·m^-3] was significantly higher than that of the Taipu River [（4 400±2 839） n·m^-3] and the Huangpu River [（2 800±1 315） n·m^-3], indicating a significant spatial distribution difference. The particle size of MPs was mainly distributed in the range of 0.1-0.5 mm, with transparent, black color, and fibers as the main MPs. Polyethylene terephthalate （PET）, polystyrene （PS）, and polyamide （PA） were the major contributors of polymers, accounting for 59.5%, 10.4%, and 8.67%, respectively. Correlation analysis showed that the MPs abundance was significantly positively correlated with total nitrogen （TN）, Co （<i>R</i>=0.436,<i>P</i>&lt;0.05）, and Cd （<i>R</i>=0.478,<i>P</i>&lt;0.05）, whereas they were negatively correlated with Cu （<i>R</i>=-0.456,<i>P</i>&lt;0.05）. The MPs abundance was also significantly negatively correlated with the distance from sampling points to the factory area （<i>R</i>=-0.796, <i>P</i>&lt;0.001）. Industrial point source emissions played an important role in the migration and occurrence of MPs. The co-occurrence patterns of MPs, metal elements, and water quality index were explored based on network analysis. TN and PS were the core influencing factors. Compared with other studies in the Yangtze River Delta, the risk pollution load index of surface water MPs in the watershed was 1&lt;PLI_ZONE&lt;2, which was characterized as light pollution. The overall ecological risk of MPs in the surface water of the research basin was relatively low.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2206-2217"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144051281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Spatio-temporal Analysis of Carbon Sequestration of Wetlands in Guangdong-Hong Kong-Macao Greater Bay Area Based on the InVEST model].","authors":"Ming-Feng Zhu, Ke-Fei Zhao, Zheng Shao, Le Li","doi":"10.13227/j.hjkx.202404030","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404030","url":null,"abstract":"<p><p>The carbon sequestration capacity of wetland ecosystems is of great significance for achieving the \"carbon peaking and carbon neutrality\" goals. Spatio-temporal changes in wetlands and the carbon sequestration capacity of the wetland ecosystem in the Guangdong-Hong Kong-Macao Greater Bay Area （GBA） during 1990 and 2020 were investigated based on long-term series and refined wetlands classification datasets. The results showed that： First, the area of wetlands in the GBA increased from 1990 to 2000 and then decreased from 2000 to 2020. The total wetland area increased by 181.08 km² during the study period, with river channel and reservoirs/ponds as the main growth categories. Wetlands in the GBA were mainly distributed along the banks of the Pearl River and its tributaries, as well as in three coastal areas namely Huangmao Bay, Qi'ao Island, and Shenzhen Bay. Second, the carbon storage changing characteristics of the wetland ecosystem were similar to that of the area, which showed a similar pattern of an initial increased and subsequent decrease during the study period. The carbon storage of the wetlands decreased by 0.12×10⁶ t in the past 30 years. The order of the average carbon storage proportions of the wetland types were reservoir/pond, river channel, coastal beach, inland beach, mangrove, wetland, and lake. Third, the wetland area in the GBA increased, while the carbon storage showed a decreasing trend during the study period. The average carbon storage per unit area of wetlands continued to decrease during the study period, which indicates a continuous decline in the carbon sequestration capacity and quality of the wetland ecosystem, which could be attributed to the encroachment of human activities, such as rice cultivation and aquaculture on a large number of wetlands, leading to a continuous decline in coastal beaches with high carbon sequestration capacity. Although the area of mangrove increased rapidly, yet its area and proportion were too small to offset the carbon sequestration capacity loss induced by the mass disappearance of mudflat, floodplain, and swamp. These findings provide decision-making support for protecting wetlands and enhancing the carbon sink capacity of wetland ecosystems in the GBA.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"1964-1973"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144049436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Digital Economy Empowers Low Carbon Economy Transformation： Based on Intermediary, Threshold, and Spatial Spillover Effects].","authors":"Jun-Wei Xu, Zhi-Hua Liu, Fu-Sheng Wu","doi":"10.13227/j.hjkx.202403216","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403216","url":null,"abstract":"<p><p>In the dual context of rapid development in the digital economy and pursuit of dual carbon goals, exploring the impact of the digital economy on regional low-carbon economic transformation holds considerable importance. Based on the balanced panel data of 30 provinces from 2010 to 2021, this study empirically examined the direct, indirect, nonlinear, and spatial spillover effects of digital economy on regional low-carbon economic transformation using the panel fixed effect, intermediary effect, threshold effect, and spatial econometric models. The results showed that： ① Digital economy could significantly promote the transition of low-carbon economy, which was valid after multiple robustness tests. ② The mechanism test showed that the digital economy substantially promoted the transformation of the regional low-carbon economy by promoting green technology innovation and new urbanization. ③ The threshold effect test showed that when the level of green technology innovation was too high or the level of urbanization was in the primary stage, the role of digital economy in promoting regional low-carbon economic transformation would be weakened. ④ By constructing a spatial Dubin model, the digital economy showed a significant spatial spillover effect on the transformation of regional low-carbon economy, but the effect was stronger in the \"geographically neighboring provinces and municipalities\" than in the \"economically neighboring provinces and municipalities\".</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2089-2102"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144049734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Identifying Hydrochemical Characteristics, Control Factors, and Pollution Source of Groundwater in the Oasis Area of Toksun County, Xinjiang].","authors":"Shui-Jin Zhao, Jin-Long Zhou, Feng Jiang, Qi-Zhen Ding, Mi Lei","doi":"10.13227/j.hjkx.202404058","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404058","url":null,"abstract":"<p><p>The groundwater of the oasis areas of Toksun County, Xinjiang, including the Toksun and Kumishi oasis areas, is an important source of water for the production and daily life activities of local people. The sustainable development and utilization of groundwater resources, ecological environment protection, and maintenance of human health are crucial factors to determine the quality and pollution sources of groundwater. In July 2023, nine groups of unconfined and 12 groups of confined groundwater samples were collected from the oasis area. The main water chemical characteristic indicators were measured, and the control factors and pollution sources of groundwater in different regions were studied and discussed by the comprehensive use of mathematical statistics analyses, Piper three-plot, Gibbs chart, ion ratio, and principal component analysis. The groundwater quality was evaluated using the water quality index （WQI） method. The potential risk of NO₃^- in groundwater was evaluated by a comprehensive health risk assessment model. The results showed that the groundwater in the study area was alkaline, and the hydrochemical types were complex and diverse. The water chemical type in the Toksun oasis area mainly comprised Cl·SO₄·HCO₃-Na·Ca, whereas that in the Kumishi oasis area comprised Cl·SO₄-Na·Ca. The overall water quality in the Toksun oasis area was good, and mainly involved Class I and II water （91.7%）. The water quality in the oasis area of Kumishi was poor, and mainly involved Class IV and V water （77.8%）. The health risk assessment showed that infants and adolescents faced higher health risk in the Toksun oasis area. Infants, children, adolescents, and adults in the Kumishi oasis area faced higher health risks, with children being more sensitive to the risk of cancer caused by inorganic substances in groundwater. Source analysis results showed that groundwater of different aquifers in the study area had similar sources or evolution processes, and leaching-enrichment （F1, contribution rate of 66.1%）, human activity （F2, contribution rate of 15.8%）, and original geological conditions （F3, contribution rate of 8.0%） were the main factors affecting the evolution of groundwater quality in the study area.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2179-2192"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Cadmium Content Characteristics, Health Risk Assessment, and Soil Environmental Benchmarks in Farmland Soil and Agricultural Products in Ningxia].","authors":"Lin Chen, Ling Yang, Hong Li, Xiang-Yu Liang, Jian-Jun Ma, Jun-Mei Wang, Jin-Bao Wang, Jun-Hua Ma, Biao Jia, Bin Xue, Dan-Bo Pang, Kun Ma","doi":"10.13227/j.hjkx.202404161","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404161","url":null,"abstract":"<p><p>A precise assessment of the health risks posed by cadmium （Cd） contamination in agricultural products from regional farmland is crucial for informed pollution prevention and control decisions. This study collected 740 pairs of soil and agricultural product samples from farmland in Ningxia, focusing on Cd content detection. The evaluation encompassed Cd pollution characteristics in soil and agricultural products and assessed the associated health risk for human ingestion. Additionally, farmland soil environmental benchmark values specific to the study area were established. The results showed that soil pH levels across the study area were consistently alkaline, with values exceeding 7.3. Cd content in the soil fell within a range of 0.020 to 0.472 mg·kg^-1, lower than the pollution risk control value of agricultural soil （pH &gt; 7.5） in China （GB 2762-2017）. Average Cd content in grains and vegetables was relatively high, with values of 0.013 and 0.011 mg·kg^-1, respectively. Conversely, potatoes and fruits exhibited the lowest average Cd content at 0.002 mg·kg^-1 each. The biological accumulation coefficient of Cd in different agricultural products was less than 1, indicating no accumulation effect across all agricultural products. The single non-carcinogenic risk index （HQ） of the soil pathway to the human body was lower than 1, and the single carcinogenic risk index also had no carcinogenic risk （CR &lt; 10^-4）, but the non-carcinogenic and carcinogenic risk indices of Cd intake via soil pathways remained below significant thresholds, yet they were higher in children compared to adults. The intake of Cd through agricultural products posed no discernible health risks to either adults or children. The critical soil Cd thresholds for corn, wheat, fruit, and other grain fields derived from the species sensitivity distribution （SSD） method were 0.503, 0.336, 0.234, and 0.342 mg·kg^-1, respectively, which were lower than the risk screening values of soil environmental quality standards （GB 15618-2018） in China. Therefore, the Cd thresholds for corn, wheat, fruit, and other grain fields derived from this study were stricter than the standards. The critical values for soil Cd in rice and vegetable fields were 1.057 and 0.740 mg·kg^-1, respectively, which were higher than the corresponding risk screening values in the standard. Specifically, critical values for rice and vegetable fields were found to be higher, suggesting a relaxed threshold compared to the standard. Conversely, critical values for soil Cd in potato fields aligned closely with the existing standard. This study underscores the importance of tailoring soil environmental benchmarks to specific agricultural products, advocating for adjustments based on actual content of heavy metals in different agricultural products.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2580-2589"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144022488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Differential Responses of Indigenous Microorganisms to Salinity Changes in Lake Sediments： A Case Study of the Baiyangdian Lake and Qinghai Lake].","authors":"Jun-Yi Deng, Jie Gao, Xue-Yao Gao, Xu-Liang Zhuang","doi":"10.13227/j.hjkx.202403273","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403273","url":null,"abstract":"&lt;p&gt;&lt;p&gt;The impact of salinity stress on methane-oxidizing microorganisms in lake sediments has been recognized as influential in altering both the community structure and function, thereby affecting methane emissions in lake water. Denitrifying anaerobic methane oxidation （DAMO） is a crucial process within the lake sediment, involving a consortium of known DAMO characteristic microorganisms and associated carbon and nitrogen-transforming functional bacteria. However, the variations in DAMO flora in lake sediments under diverse salinity conditions and their implications on greenhouse gas production remain inadequately explored. To address this gap, a comparative study was conducted on the indigenous flora in sediments from two lakes with contrasting salinities, namely the saline Qinghai Lake and the freshwater Baiyangdian Lake. The &lt;i&gt;α&lt;/i&gt;-diversity analysis revealed higher Shannon and Observed-Richness indices in the Baiyangdian Lake sediment compared to the Qinghai Lake sediment, while the Inv-Simpson index showed the opposite trend. While the dominant microbial populations were similar at the phylum level, significant differences were observed in the abundance and proportion of common microbial populations. Notably, the salinity of lake water exhibited a negative correlation with microbial diversity and methane-oxidizing microbial diversity in sediments. Further investigation on the indigenous DAMO microflora in the lake sediments under different salinity conditions revealed distinct patterns. Specifically, anaerobic microcultures were carried out at different salinity gradients （0, 11, and 110 g·L&lt;sup&gt;-1&lt;/sup&gt;）, with CH&lt;sub&gt;4&lt;/sub&gt; and KNO&lt;sub&gt;3&lt;/sub&gt; as substrates. The rates of nitrite formation and nitrate consumption were lower in the Qinghai Lake sediment compared to those in the Baiyangdian sediment with respect to individual salinity. CO&lt;sub&gt;2&lt;/sub&gt; production in the Baiyangdian sediment decreased with increasing salinity. Additionally, for the Baiyangdian sediment, methane oxidation and nitrous oxide production were lower in the high salinity group than those in the low salinity group. In the Qinghai Lake sediment, the most active methane oxidation was observed at the original sample's salinity （11 g·L&lt;sup&gt;-1&lt;/sup&gt;）, with the highest methane oxidation reaching 481.67 μmol·L&lt;sup&gt;-1&lt;/sup&gt; and the lowest nitrous oxide production around 1.69 μmol·L&lt;sup&gt;-1&lt;/sup&gt;. The methane oxidation capacity of the Qinghai Lake sediment cultured at its original salinity was better than that of other salinity groups, and the yield of nitrous oxide was also lower. These results indicated that DAMO flora in high salinity lakes could adapt to the salinity of their habitats after long-term screening and domestication. Therefore, the significant difference in indigenous microorganisms in the sediments of saltwater and freshwater lakes lead to the differences in their response to changes in the salinity environment and further affect the DAMO process in lakes. Qu","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2611-2620"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144014196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Evolution of PM_2.5 and O₃ Pollution in the Qinhuangdao City During Sustained Air Quality Improvement from 2018 to 2022].","authors":"Li-Jie Shi, Na Suo, Bo-Jian Ma, Ting Tang, Shuo Wang, Xin-Yi Ma, Xiao-Teng Ji, Yu-Ting Tian, Hao Zhu, Hong-Ya Niu","doi":"10.13227/j.hjkx.202402150","DOIUrl":"https://doi.org/10.13227/j.hjkx.202402150","url":null,"abstract":"<p><p>In order to understand the characteristics of PM_2.5 and O₃ composite pollution in the Qinhuangdao City, analyses were conducted based on ambient air pollutant concentration, meteorological, and PM_2.5 chemical component data in the Qinhuangdao City from 2018 to 2022. The results revealed that the annual mean, seasonal mean, number of polluted days, and maximum daily mean of PM_2.5 showed an overall decreasing trend from 2018 to 2022. The annual and spring-autumn averages fell by 24.32%, 31.65%, and 21.05%, respectively. The average PM_2.5 mass concentration decreased by 10.39% on PM_2.5-polluted days. According to the meteorological elements, the prevailing wind direction was westerly in spring and autumn and during all pollution periods. During the PO composite pollution period, the wind direction of the high concentration pollutants was dominated by the southwest wind, and the wind speed was generally less than 2 m·s^-1 during each period. Temperatures at the time of moderate PM_2.5 pollution were close to the mean spring and autumn temperatures, and temperatures at PO3 and PO4 were higher than the autumn mean and lower than those at the time of O. Among the water-soluble ions in spring and autumn, the mass concentration of WSIIs decreased by 34.99% during spring, and the mass concentration of WSIIs was similar during autumn from 2019 to 2022. Among the carbon fractions, OC mass concentrations were similar during autumn, while EC, spring OC and EC mass concentrations decreased by 41.11%, 28.18%, and 40.29%, respectively. SNA mass concentrations in water-soluble ions accounted for more than 90% of WSIIs in all pollution periods, and SNA mass concentrations were higher in PO than in O during spring and autumn. For the same types of pollution, Cl^- mass concentrations were higher during spring than during autumn. Among the carbon fractions, OC mass concentrations were highest during the periods of moderate PM_2.5 pollution （P3 and P4）, and SOC mass concentrations were higher during PO than during the P and O periods during spring and autumn. The values of OC/EC and EC/TC showed that the carbon component was mainly obtained from fossil fuel combustion in the P and PO periods and from biomass combustion and fossil fuel combustion in the O period.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 4","pages":"2115-2124"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143999668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}