环境科学最新文献

{"title":"[Content and Health Risks of Microplastics and Phthalate Esters in Bottled Water].","authors":"Xiao-Ge Liang, Rui-Yao Guo, Meng-Fei Su, Xue-Jing Yang, Bo Yao, Jian-Sheng Cui","doi":"10.13227/j.hjkx.202310185","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310185","url":null,"abstract":"<p><p>To study the content and health risks of microplastics （MPs） and phthalate esters （PAEs） in bottled water, a quantitative analysis of MPs was conducted by using Rose Bengal staining and stereomicroscopy. Seven PAEs were quantified by using gas chromatography-triple quadrupole tandem mass spectrometry （GC-MS/MS）. The daily intake of MPs was estimated and the carcinogenic and non-carcinogenic risks of PAEs were evaluated through a health risk assessment model. The results showed that the abundance of MPs in 21 bottled waters ranged from 48 n·L^-1 to 216 n·L^-1 （with the median abundance of 88 n·L^-1）. The majority （72.1%） of MPs were fibrous in shape, and fragments accounted for only 27.9%. The average proportion of small-sized （10-50 μm） MPs was 33.9%, and that of large-sized MPs （&gt;500 μm） was 4.3%. Most MPs were blue. The ∑(PAEs) in bottled water was 1.15-2.47 μg·L^-1 （average 1.62 μg·L^-1）. PAEs detected with high frequencies （100%） included dimethyl phthalate （DMP）, diethyl phthalate （DEP）, diisobutyl phthalate （DIBP）, di-<i>n</i>-butyl phthalate （DBP）, and di（2-ethylhexyl） phthalate （DEHP）, while the detection frequencies of butylbenzyl phthalate （BBP） and di-n-octyl phthalate （DNOP） were relatively low. The concentrations of DBP, DEHP, and DEP were all below the standard limits for drinking water in China. The ∑(PAEs) in the migration experiments was 0.61-2.04 μg·L^-1 （average 1.33 μg·L^-1）. The migration amounts of DBP and DEHP were also within the allowable range under the condition of 60℃ for 10 days. Seven PAEs were detected in both the bottles and caps, and the average content of DEHP in bottles was the highest, while DBP had the highest content in caps. The estimated intake of MPs （EDI） by drinking bottled water in different age groups of humans was 2.87 n·（kg·d）^-1 for adults, 3.87 n·（kg·d）^-1 for children, and 5.85 n·（kg·d）^-1 for infants. The carcinogenic risks of DEHP in 21 bottled water samples and the migration test were less than the maximum acceptable risk level （1×10^-6）, and the non-carcinogenic risk indices （HIs） of PAEs were all less than 1, indicating no non-carcinogenic risk to humans； however, the risk value of infants and children was higher than that of adults and should not be ignored.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"6104-6111"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509623","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":"[Spatiotemporal Evolution and Simulation Prediction of Ecosystem Carbon Storage in the Yellow River Basin Before and After the Grain for Green Project].","authors":"Xu-Meng Duan, Mei Han, Xiang-Lun Kong, Jin-Xin Sun, Hui-Xin Zhang","doi":"10.13227/j.hjkx.202310021","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310021","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Under the background of \"dual carbon\", the impact of the implementation of the Grain for Green project on the carbon storage of the ecosystem in the Yellow River Basin must be explored, which can serve as an important reference for improving the policy implementation of the new round of the Grain for Green project and improving the carbon sink capacity of the ecosystem in the Yellow River Basin. In this study, 1990, before the implementation of the project, was selected as the starting year of the research period, and 2020, after the implementation of the two rounds of the project, was selected as the end year of the research period. Based on the ecosystem type data from 1990 to 2020, the InVEST model was used to calculate the soil carbon pool, underground carbon pool, below carbon pool, dead organic matter carbon pool, and total carbon storage of ecosystems in the Yellow River Basin and the area where the project was implemented from 1990 to 2020. The results showed that： ① From 1990 to 2020, the area of forest ecosystem in the Yellow River Basin expanded by 26 610.06 km&lt;sup&gt;2&lt;/sup&gt;, and the area of farmland decreased by 46 849.06 km&lt;sup&gt;2&lt;/sup&gt; after the implementation of two rounds of the project. Spatially, the upper reaches of the Yellow River were dominated by grassland and other ecosystems； the middle reaches of the Yellow River were dominated by farmland, forest, and grassland ecosystems； and the lower reaches of the Yellow River were dominated by farmland ecosystems. ② From 1990 to 2020, the carbon storage in the project implementation area showed a fluctuating and increasing trend, and the total carbon storage reached a peak （219.47×10&lt;sup&gt;8&lt;/sup&gt; t） in 2009 and decreased to 218.59×10&lt;sup&gt;8&lt;/sup&gt; t in 2020 due to the decrease of grassland ecosystem from 2010 to 2020. Spatially, the high-value areas of carbon storage were distributed in Aba Tibetan and Qiang Autonomous Prefecture of Sichuan Province and the southern tip of Gansu Province in the upper reaches of the forest and grass accumulation and in the whole of Shanxi Province and the central and southern parts of Shaanxi Province in the middle reaches. Shangluo City in Shaanxi Province and Alxa League in Inner Mongolia Autonomous Region were prefecture-level cities with the highest and lowest average carbon density. ③ In 2035, the carbon storage loss of the natural development scenario was predicted to be 0.83×10&lt;sup&gt;8&lt;/sup&gt; t, and the other three scenarios would increase this loss. Under the moderate farmland return scenario, the Yellow River Basin ecosystem had the strongest carbon sequestration capacity, and the predicted carbon storage would increase by 2.72×10&lt;sup&gt;8&lt;/sup&gt; t compared with that in 2020, and the deep farmland return scenario was the comprehensive optimal scenario. Therefore, in the future, the Yellow River Basin could refer to the deep farmland return scenario to optimize and adjust the implementation plan of the Grain for Green project, and the predicted val","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5943-5956"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509656","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":"[Functional Genes and Metabolic Pathways of Nitrogen Metabolism Microorganisms in Lake Sediments：A Case Study of Hongfeng Lake, Guizhou Province].","authors":"Qian Liu, Xiao Chen, Yan-Cheng Li, Yu-Han He, Jiang Li","doi":"10.13227/j.hjkx.202310134","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310134","url":null,"abstract":"<p><p>The nitrogen cycle is of great importance for material circulation and energy flow in lake ecosystems. It is driven by microorganisms in lake sediments and can contribute to balancing lake ecosystems. In this study, physical and chemical properties of the sediments sampled from Hongfeng Lake in Guizhou Province were assayed and analyzed using metagenomics to reveal relevant microorganisms, functional genes, metabolic pathways, and their relationships throughout nitrogen metabolism. The results showed that bacteria were dominant, and the top three relative abundant genera were <i>Thiobacillus</i> （16.64%）, <i>Rubrivivax</i>（9.43%）, and <i>Nitrospira</i> （7.09%）. Only six pathways, including nitrogen fixation, nitrification, denitrification, assimilatory nitrate reduction, dissimilatory nitrate reduction, and complete nitrification, were detected in total, of which denitrification and dissimilatory nitrate reduction were the primary processes, but anaerobic ammonia oxidation was not detected. Bacteria and archaea participated in these six pathways, while eukaryotes only functioned in dissimilatory nitrate reduction, denitrification, and complete nitrification. Ammonia nitrogen, nitrate nitrogen, and total phosphorus, as main environmental factors affecting the distribution of functional genes for nitrogen metabolism, differentiated with each other in their respective real-world conditions. A positive correlation （95.04%） was observed between the functional genes and microorganisms, and <i>narG</i>, <i>narZ</i>, and <i>nxrA</i> possessed the highest abundance and the highest host genes. On this basis, these findings are expected to further elucidate the nitrogen cycle of typical karst lakes in Guizhou Province.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"6086-6095"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509645","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":"[Key Issues and Challenges in Establishing Regionally Differentiated Water Quality Standard in China].","authors":"Ying-Cai Tang, Dong-Bin Wei, Yin-Hu Wu, Zhuo Chen, Yun Lu, Hua-Nan Gao, An-Ran Liao, Nan Huang, Hong-Wei Xu, Zi-Tong Liao, Ren Ding, Han Yan, Zhuo-Wei Zhang, Hong-Ying Hu","doi":"10.13227/j.hjkx.202310024","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310024","url":null,"abstract":"<p><p>The goal of environmental management in China is transitioning from pollution control to the improvement of ecological quality. The establishment of regional differential water quality standards can better adapt to the ecological characteristics and development needs of different regions. Given the shortcomings of current water quality standards and the needs of technological development, this study analyzed the causes and influencing factors of regional differences in water quality standards and summarized China's regional variations in areas such as the characteristics of receiving water bodies, social attributes, climate conditions, physicochemical properties of water, and aquatic biotic populations. It also examined the impact of regional characteristics on the assessment of biological toxicity. Based on these analyses, the study identified key scientific questions that may arise in the development of regional differential water quality standards in China and outlined future critical research directions in this field. These directions include developing theories and methods for determining the effluent dilution coefficient, establishing methods for identifying regional key water quality indicators and assessing their impact on water quality standards, determining regional characteristic species and their influence on water quality standards, and formulating theories and methods for categorizing different regions across the country. The aim of the study was to provide a reference for the scientific establishment of water quality standards in China.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5748-5760"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509649","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":"[Coupling Coordination Measurement and Multi-dimensional Conflict Diagnosis among Territorial Space Functions].","authors":"Xi-Ping Zheng, Zhu-An Chen","doi":"10.13227/j.hjkx.202311069","DOIUrl":"https://doi.org/10.13227/j.hjkx.202311069","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Exploring the relationship between urban, agricultural, and ecological functions is crucial for optimizing the territorial spatial patterns and achieving balanced territorial spatial development. Based on the classification system of \"urban-agricultural-ecological\" territorial spatial planning and with the help of multi-source data, including land use, population density, nighttime light, road network, precipitation, and county statistical data from 2010 to 2020, we constructed an evaluation index system of territorial space functions at the grid scale in the Poyang Lake Ecological Economic Zone. The coupling coordination levels among territorial space functions was measured using the coupling coordination degree model and spatial autocorrelation analysis. Moreover, the multi-dimensional function conflict identification model was used to diagnose the type and intensity of function conflicts. The results showed that： ① The urban function was mainly improved, accounting for 75.67%. The grids with high function evaluation index were mainly located in the south of the study area, whereas the intensity of urban function improvement in the north was higher than that in the south. Otherwise, the agricultural and ecological functions were mainly reduced, accounting for 77.44 % and 57.66%, respectively, and the majority of grids with a significant decrease were distributed in the south of Poyang Lake. ② From 2010 to 2020, the coupling coordination type was dominated by an imbalance recession, accounting for 53.87% and 49.89 %, respectively. However, the number of grids with crucial imbalance and primary coordination was reduced, and the coupling coordination types tended to change from both ends to the middle. The coupling coordination hot spots were mainly concentrated in the southern plain, whereas the cold spots were mainly distributed in the northern mountainous and hilly areas, both of which showed a reducing trend. However, in the north of Poyang Lake, a small number of hot spots, distributed along the lake area with relatively flat terrain, showed an expanding trend. ③ The intensity of four territorial space function conflicts was mainly moderate or severe. In addition to the slight positive trend of 'urban-agricultural' function conflict, the function conflicts of \"urban-ecological\", \"agricultural-ecological\", and \"urban-agricultural-ecological\" were all aggravated. The grids with aggravating conflicts were mainly distributed in the Ganjiang River and Fuhe River Basin. The major reason for the aggravation was that the urban function increased obviously, whereas the ecological and agricultural functions decreased significantly. In conclusion, in both the coupling coordination types and multi-dimensional conflicts among territorial space functions, significant spatial differences existed； thus, proposing optimization strategies according to local conditions is necessary. Additionally, the protection of ecological and agricultural spaces during","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5868-5879"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509624","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":"[Analysis of Ozone Pollution and Precursor Control Strategies in the Pearl River Delta During Summer and Autumn Transition Season].","authors":"Qing-Qing Yu, Wei-Qiang Yang, Cheng-Lei Pei, Xin-Ming Wang","doi":"10.13227/j.hjkx.202310051","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310051","url":null,"abstract":"<p><p>To analyze the causes of ozone pollution in the Pearl River Delta （PRD） Region during the summer and autumn transition seasons, a case study was carried out in Guangzhou, which is located in the center of the PRD Region, to analyze the ozone photochemical production and destruction pathways as well as emission reduction scenarios using a box model based on comprehensive observation. The results showed that the stagnant meteorological conditions and high temperature during the observation period were suitable for the photochemical production of ozone, which led to widespread and prolonged ozone pollution. Aromatic hydrocarbons （AHs） contributed the most to the ozone formation potential （OFP）, and <i>m</i>/<i>p</i>-xylene, toluene, and <i>o</i>-xylene were the major three VOC species contributing to the OFP. Box model analysis revealed that the averaged net O₃ production rate during the polluted period was 23.2×10^-9 h^-1 and the peak reached 39.2×10^-9 h^-1. The HO₂·+NO and NO₂+·OH reaction pathways contributed the most to the local photochemical ozone production （51.2%） and destruction （47.0%）, respectively. Observed ozone concentration was primarily controlled by both the local photochemical O₃ production and the export-dominated transport. The RIR and EKMA analyses showed that O₃ formation in Guangzhou during the summer-autumn transition seasons was mainly a VOC-limited regime and AHs showed the greatest sensitivity to O₃ production. Toluene, <i>m</i>/<i>p</i>-xylene, <i>o</i>-xylene, <i>n</i>-butane, and propylene were the five key components affecting O₃ generation. The analysis of reduction scenarios showed that reducing anthropogenic VOC emissions was the most favorable way to reduce O₃ concentrations； however, if NO<i>_x</i> emission was controlled after reducing VOCs, the O₃ concentration would rebound in a short time. Our results suggested that the synergistic reduction of VOCs and NO<i>_x</i> while mainly focusing on VOCs alleviation should be implemented to continuously reduce ozone concentrations in the future.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5695-5705"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509595","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":"[Predictive Model for O₃ in Shanghai Based on the KZ Filtering Technique and LSTM].","authors":"Ling-Xia Wu, Jun-Lin An, Dan Jin","doi":"10.13227/j.hjkx.202311150","DOIUrl":"https://doi.org/10.13227/j.hjkx.202311150","url":null,"abstract":"<p><p>In this study, a Kolmogorov-Zurbenko （KZ） filter was proposed to decompose the original ozone （O₃） sequence to improve the accuracy of ozone long-term series prediction and select relevant meteorological features. Furthermore, the enhanced maximal minimal redundancy （mRMR） feature selection technique was combined with the support vector regression （SVR） approach to select the most illuminating meteorological features. Subsequently, from May to August 2023, during high ozone concentration periods, a long short-term memory network （LSTM） was utilized to assess and predict high ozone concentration periods at the monitoring stations of Jingan （urban area）, Pudong-Chuansha （suburban area）, and Dianshan Lake （suburban area） in Shanghai. The results showed that pressure, temperature, humidity, boundary layer height, and wind direction were the best combinations of O₃ baseline and short-term components, as chosen by feature screening. The <i>R</i>² values for Jingan Station, Pudong-Chuansha Station, and Dianshan Lake Station were 0.86, 0.83, and 0.85, respectively. The RMSE values were 18.26, 18.74, and 20.02 μg·m^-3, respectively. These findings suggest that decomposing the original O₃ sequence improved the prediction accuracy of ozone concentrations. Additionally, as indicated by the <i>R</i>² and RMSE values found for every monitoring station, feature screening preserved the model's predictive performance.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5729-5739"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509632","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":"[Path of Co-control of Pollution and Carbon Emissions Reduction in Typical Parks of Pharmaceutical and Health Industry in Beijing].","authors":"Xu Liu","doi":"10.13227/j.hjkx.202310178","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310178","url":null,"abstract":"<p><p>The agglomeration of carbon emissions from the pharmaceutical and health industry has been growing gradually in Beijing. Conducting research on the path of co-control of pollution and carbon emission reduction in industrial parks is essential to realize synergy between economic development, pollution reduction, and green low-carbon. Based on the production activity data in 2020 of two typical parks of manufacturing and R&D, we selected six measures for co-control of pollution and carbon emission reduction and set up a synergistic development scenario to explore the collaborative development path of different types of parks. The results showed that： ① The primary carbon emission source in the two parks was energy consumption, such as natural gas and electricity, whereas the major pollution source was from key polluting enterprises. The emissions in the R&D park were significantly lower than those in manufacturing parks, with atmospheric pollutant emissions accounting for 25% of the manufacturing park's emissions. ② Energy structure and intensity, along with pollutant emission reduction measures, contributed 62.6% and 37.4% to pollution and carbon emission reduction for the R&D park and 81.6% and 13.5% for manufacturing park, respectively. ③ Adjusting the energy structure of the park and prioritizing the management of key polluting enterprises could achieve synergistic emission reduction, with the rate of emission reduction primarily reflecting atmospheric pollutants. Reducing energy intensity could also facilitate synergistic emission reduction, with a rapid rate of carbon emission reduction. Optimizing the industrial structure could lead to different degrees of pollution and carbon emissions increasing synergistically or not synergistically, owing to the particularity of the industrial structure of the park. ④ Applying measures to adjust the energy structure and reduce energy intensity and pollutant emissions into the collaborative path should be a priority. The governance scope of key polluting enterprises should be appropriately expanded in manufacturing parks. The synergistic effect of public environmental protection facilities of R&D parks should be focused on, in addition to reducing corporate pollutant emissions. Measures to optimize industrial structure at the park level should be adjusted to local conditions and scientifically guide industrial transformation and the settlement of high-tech enterprises.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"5624-5631"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509652","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":"[Greenhouse Gas Emissions Characteristics and Driving Factors Analysis in the Eutrophic Saline Lake Daihai Lake].","authors":"Zong-Fu Lu, Xiao-Hong Shi, Guo-Hua Li","doi":"10.13227/j.hjkx.202311125","DOIUrl":"https://doi.org/10.13227/j.hjkx.202311125","url":null,"abstract":"<p><p>To investigate the greenhouse gas emission characteristics and driving factors of eutrophic saline lakes in northern China, considering Daihai Lake in Inner Mongolia as an example, 10 monitoring sites were selected based on hydrological distribution characteristics in April, July, and October 2023. Using headspace gas chromatography and modeling methods, dissolved concentrations and exchange fluxes of carbon dioxide （CO₂）, methane （CH₄）, and nitrous oxide （N₂O） were determined in the nearshore zone, open lake area, and lake center surface water. During the study period, Daihai Lake exhibited significant seasonal variations in greenhouse gas concentration and flux. The average concentrations of CO₂, CH₄, and N₂O in surface water were （26.52 ± 17.58） μmol·L^-1, （282.30 ± 172.30） nmol·L^-1, and （9.09 ± 1.64） nmol·L^-1, respectively. The average fluxes were （5.29 ± 11.98） mmol·（m²·d）^-1, （178.24 ± 63.34） μmol·（m²·d）^-1, and （-0.74 ± 1.28） μmol·（m²·d）^-1, with cumulative emissions of 50 770.77, 543.52, -4.21 kg·km^-2 and a global warming potential （expressed in CO₂-equivalent） of 50 770.77, 15 218.49, -1 254.48 kg·km^-2. Daihai Lake acted as a source of atmospheric CO₂ and CH₄ but a sink for N₂O during the study period. Correlation and stepwise regression analyses revealed that pH and total dissolved solids （TDS） influenced CO₂ concentration and flux, while the factors affecting CH₄ were water temperature （WT）, water depth （WD）, wind speed （WS）, oxidation-reduction potential （ORP）, and total nitrogen （TN）. For N₂O, the influencing factors were WT, WS, and TN. Additionally, Daihai Lake's eutrophication and salinity characteristics influenced the generation and emission of greenhouse gases. This study provides insights into the greenhouse gas dynamics and environmental factors in eutrophic saline lakes like Daihai Lake.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"6157-6170"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509646","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":"[Effects of Microplastics on Soil N₂O Emission and Nitrogen Transformations from Tropical Agricultural Soils].","authors":"Xiao-Tong Wang, You-Feng Leng, Jun-Jiao Wang, Xiao-Min Huang, Ya-Jun Fu, Chang-Hua Fan, Wen-Long Gao, Wen Zhang, Zi-Yu Ning, Miao Chen","doi":"10.13227/j.hjkx.202310172","DOIUrl":"https://doi.org/10.13227/j.hjkx.202310172","url":null,"abstract":"<p><p>A widespread concern had been there regarding soil ecological and environmental problems caused by microplastic pollution in agricultural soils. A controlled laboratory incubation experiment was performed to examine the effects of different types of microplastics on soil properties, N₂O emissions, and nitrogen （N） transformations in tropical arable soils from a pepper-corn cropping system in Hainan Province. Three treatments were done： soil without microplastics （CK） and soil amended with 5% of polyethylene （PE） or with 5% of polybutylene adipate co-terephthalate （PBAT）. The results showed that both types of microplastic addition increased soil pH, soil organic carbon （SOC）, and dissolved organic carbon （DOC） contents, with stronger treatment effects observed for PBAT than those for the PE treatment. In addition, the PE and PBAT treatments increased soil ammonium nitrogen （NH₄⁺-N） contents by 66.07% and 119.65% and decreased nitrate nitrogen （NO₃^--N） contents by 8.56% and 29.68%, respectively. Compared to those in the CK treatment, the addition of PBAT significantly increased soil N₂O emissions by 254.92% （<i>P</i> < 0.05）, whereas that of PE produced no significant effects. Furthermore, both the PE and PBAT treatments increased soil net nitrogen mineralization rate （NMR） and decreased soil net nitrification rate （NNR）, with more obvious treatment effects observed in PBAT than in the PE treatment. PBAT addition increased the abundance of <i>ureC</i>, while PE had no significant effects. Microplastic addition reduced the abundance of nitrifying gene abundances （AOA-<i>amoA</i>, AOB-<i>amoA</i>, and <i>nxrA</i>）, with more obvious treatment effects found in the PBAT treatment. Further, PBAT addition significantly increased the gene abundances of <i>nirK</i>, <i>nirS</i>, <i>nosZ</i>, and fungal <i>nirK</i> （<i>P</i> < 0.05）, whereas the addition of PE had no significant effect on those gene abundances. Soil N₂O emissions had positive relationships with NH₄⁺-N intensity, pH, DOC, SOC, and <i>nirS</i> abundance. In conclusion, biodegradable microplastics addition produced stronger influences on soil properties and N transformations than the non-biodegradable one in tropical arable soils and aggravated soil N₂O emissions mainly by promoting denitrification.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":"45 10","pages":"6139-6147"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509640","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}