Huanjing Kexue/Environmental Science最新文献

{"title":"[Occurrence and Distribution of Potential Dangerous Biological Agents in Beijing Suburban Rivers].","authors":"Yun-Wei Cui, Yuan Xin, Yao-Fang Zhang, Lei Li, Zhi-Han Ye, Yuan-Song Wei, Jun-Ya Zhang","doi":"10.13227/j.hjkx.202307049","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307049","url":null,"abstract":"<p><p>Dangerous biological agents （DBAs） refer to microorganisms, toxins, and other biological substances that have the potential to cause significant harm to humans, animals, plants, and the environment. They are the primary target of the prevention and response in China's Biosafety Law, and it is of great importance to clarify the characteristics of DBAs in the Beijing suburban rivers for the insurance of the water safety in Beijing. The typical Beijing suburban rivers （Mangniu River, Chaohe River, and Baihe River） were selected, and the occurrence and distribution of DBAs concerning the molecular biology composition as the nucleic acid （antibiotic resistance genes, ARGs）, nucleic acid and proteins （viruses）, and intact cellular structures （pathogens） were determined based on the metagenomics. The results showed that there was a high abundance of multidrug-resistant ARGs in the water and substrates of the urban river； on average, they made up 74.11% ±6.82% of the total, and the abundance of aminoglycoside and MLS （macrolide-lincosamide-streptomycin）-resistant ARGs was the highest, but the predominant subtypes of ARGs were of low risk and had limited transmission potential. The viruses in the tributary mainly belonged to the phages, most of which were Kyanoviridae and Peduoviridae, with averages of 16.98% ±8.44% and 16.19% ±10.79%, respectively. Eukaryotic viral populations consisted mainly of members from the Mimiviridae and Phycodnaviridae families, with averages of 10.37% ±12.68% and 8.34% ±6.97%, respectively, whereas there were few viruses related to human and animal diseases. The pathogenic bacteria mainly contained <i>Neisseria meningitidis</i>, <i>Brucella suis</i>, <i>Salmonella enterica,</i> and <i>Burkholderia pseudomalle</i>, with averages of 19.17% ±3.63%, 12.76% ±2.88%, 11.22% ±1.95%, and 8.26% ±1.84%, respectively. The composition and abundance of pathogenic bacteria varied significantly among different tributaries and locations, possibly owing to water quality, pollution sources, environmental factors, and human activities. These findings can provide data support for the water safety management and biological risk control of Beijing suburban rivers.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634823","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":"[Xiaojiang River Basin Ecological Environmental Quality Spatiotemporal Pattern and Evolutionary Trend Analysis Using GEE from 1990 to 2022].","authors":"Hui-Lin Zong, Xiao-Lun Zhang, Xi-Ping Yuan, Jie Lü, Ming-Long Yang, Shu Gan","doi":"10.13227/j.hjkx.202308061","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308061","url":null,"abstract":"<p><p>Assessment and monitoring of the quality of the ecological environment in the area is a very important fundamental task in the development of ecological civilization in the Xiaojiang River Basin in Yunnan Province, which serves as a demonstration area for ecological restoration in the upper reaches of the Yangtze River. The Landsat remote sensing images from 1990, 1995, 2000, 2005, 2010, 2014, 2018, and 2022 were chosen, and the four indexes of greenness （NDMVI）, humidity （WET）, dryness （NDBSI）, and heat （LST） were extracted. The remote sensing ecological index （RSEI） was created using the principal component analysis method, then the spatial and temporal patterns and trends of ecological quality in the Xiaojiang River Basin between 1990 and 2022 were examined using the GEE platform, ArcGIS 10.7 platform, and Python platform, combining the analysis methods of geographic information mapping, coefficient of variation, Mann-Kendall trend test, Sen's slope estimation, and Hurst's index. The findings demonstrated that： ① the ecological quality of the study area had more obvious geographic differentiation spatially, and by 2022, the areas with excellent and good ecological quality grades were primarily distributed in the areas with better alpine vegetation cover, and those with poor ecological quality were primarily distributed in the areas of the mudslide ravines with relatively low terrain. On a time scale, the study area's RSEI index increased from 0.41 in 1990 to 0.55 in 2022, with a fluctuating overall trend of ecological quality improvement and an average increase of 0.048（10 a） ^-1； this progress was directly related to a number of ecological construction initiatives that have been energetically carried out, such as converting farms to forests, preventing mudslides, saving soil and water, managing heavy metal contamination, etc. ② The RSEI was more appropriate for the evaluation of ecological quality in alpine ravine areas because, in comparison to the NDVI index, the NDVMI adopted in this study was more sensitive to vegetation information in topographic undulation areas, especially in shaded areas, and could more accurately and quantitatively describe the vegetation information. ③ The RSEI in the Xiaojiang River Basin had a mean coefficient of variation of 0.202. Overall, its volatility was low, and its high volatility was mostly concentrated in the mudslide gully area along both sides of the Xiaojiang River fracture zone, where the surface was made up of bare rocks and sediment that was easily impacted by the changing of the seasons, the climate, and human activity. ④ The quality of the ecological environment in the region was significantly improving, with the rising area reaching 85.72% of the total area and the declining area accounting for approximately 10.15% of the total area. The future trend of change will be dominated by ongoing improvement and future degradation, accounting for 44.75% and 39.97%, respectively. It is im","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634789","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":"[N₂O Emission Factors from Wastewater Treatment Plants Based on Literature Statistics and Model Fitting].","authors":"Peng-Yu Wang, Xiu-Heng Wang","doi":"10.13227/j.hjkx.202307028","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307028","url":null,"abstract":"<p><p>The emission of nitrous oxide （N₂O） during wastewater treatment cannot be ignored. The analysis of statistical data from literature based on 126 empirical studies revealed that the geographical factors of wastewater treatment plants （WWTPs） had a significant impact on N₂O emission factors. However, the N₂O emission factors of WWTPs in all regions of the world were generally lower than the Intergovernmental Panel on Climate Change （IPCC） recommended values. In China, the N₂O emission factors （in N₂O-N/N_influent） of WWTPs were approximately 0.000 35-0.065 20 kg·kg^-1. Meanwhile, the N₂O emission factors of different wastewater treatment processes were also significantly different, especially since the sequencing batch reactor （SBR） process had higher emissions. The use of uniform default emission factors for accounting was prone to overestimate N₂O emissions, and it is recommended that countries conduct actual monitoring or modeling studies to develop categorical emission factors suitable for local conditions. In addition, the N₂O emission factor based on total nitrogen （TN） removal was weakly negatively correlated with TN removal in 126 empirical data, which was more in line with bioprocessing stoichiometry and could provide an accurate accounting method for N₂O. To this end, a digital twin model was developed to dynamically simulate a case anaerobic-anoxic-aerobic （AAO） WWTP to comprehensively quantify the dynamic emission behavior of N₂O, which demonstrated that N₂O emissions had significant seasonal and daily variability and were only equivalent to 11% of the calculated value of the emission factor based on the IPCC recommendation. Comparing the scatter linear fitting and categorical mean exponential fitting methods, it was found that the latter could more accurately reflect the negative correlation between the N₂O emission factors and the TN removal rate, and an exponential regression equation between the average N₂O emission factor based on the amount of TN removed and the TN removal rate was further developed to predict the N₂O emission. The dynamic simulation and categorical index fitting methods provided in this study are important references for the accurate accounting of N₂O emissions in similar WWTPs and provide help for understanding and responding to the N₂O emission problems.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634781","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":"[Variation Characteristics and Source Analysis of Atmospheric Ozone Pollution in Guanzhong Region].","authors":"Xing Wang, Ai-di Huo, Ji-Qiang Lü, Zhi-Xin Zhao, Jian Chen, Fang-Qian Zhong, Lu-Ying Yang, Lei Yang","doi":"10.13227/j.hjkx.202305229","DOIUrl":"https://doi.org/10.13227/j.hjkx.202305229","url":null,"abstract":"<p><p>Guanzhong urban agglomeration has a good development foundation and great development potential, and it has a unique strategic position in the national all-round opening up pattern. In recent years, the problem of near-surface ozone （O₃） in the Guanzhong Region has become increasingly prominent, which has become a bottleneck affecting the continuous improvement of air quality. In order to effectively prevent and control O₃ pollution, this study analyzed the characteristics of annual, monthly, and daily changes in O₃ concentration in the Guanzhong Region based on the environmental monitoring data from 2018 to 2021. A geo-detector was used to study the driving factors of the spatial differentiation of O₃ concentration, and the sources of O₃ were analyzed using a backward trajectory model and emission inventory construction. The results showed that the daily and monthly variation in O₃ concentration in the Guanzhong Region were unimodal. The daily maximum value appeared at 15：00, the minimum value appeared at 07：00, the peak value of the monthly average appeared in June, and the valley value appeared in December. The O₃ concentration was highest in summer, followed by that in spring, and the lowest in winter. The days of O₃ exceeding the standard showed mainly mild pollution, and moderate and above pollution showed a trend of decreasing first and then increasing. The O₃ concentration in the Guanzhong Region was mainly closely related to precursors and meteorological factors, and the explanatory power of the interaction of each factor was significantly greater than that of any single factor. The regional transport of O₃ concentration in the Guanzhong Region was mainly affected by easterly airflow, followed by the northwest direction, with the potential source areas located mainly in Henan Province and Hubei Province. The main local sources of volatile organic compounds （VOCs） were solvent use sources, process sources, and mobile sources, and the main emission sources of nitrogen oxides （NO<i>_x</i>） were mobile sources and industrial production combustion sources. The research results have a guiding significance for O₃ joint prevention and control in the Guanzhong Region.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634786","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":"[Spatial Prediction and Influencing Factors Analysis of Soil Salinization in Coastal Area Based on MGWR].","authors":"Ying Song, Ming-Xiu Gao, Jia-Fan Wang, Ze-Xin Xu","doi":"10.13227/j.hjkx.202307195","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307195","url":null,"abstract":"<p><p>Quantitative analysis of the spatial non-stationary characteristics of soil salinization influencing factors and the prediction of its spatial distribution are of great significance for the rational use of coastal saline soil resources and the formulation of local prevention and control measures. In this study, the Hekou District of Dongying City, Shandong Province, was used as the study area, and the descriptive statistics of soil salinization status were conducted using classical statistical methods. Spatial autocorrelation theory was used to explore the characteristics of global and local spatial structure of soil salinization in the study area. Influential factors related to soil salinity were selected, and multivariate linear regression （MLR）, geographically weighted regression （GWR）, and multi-scale geographically weighted regression （MGWR） methods were used to model and predict the spatial distribution of soil salinity in the study area and to analyze the spatial heterogeneity of the effects of different influencing factors on soil salinity. The results showed that： ① The mean value of soil salinity in the study area was 5.84 g·kg^-1, indicating severe salinization, with a global Moran's <i>I</i> index of 0.19 （<i>P</i><0.00） and obvious spatial aggregation characteristics. ② Among the three models, the MGWR model had the highest modeling accuracy. Compared with that of the MLR model, the <i>R</i>_adj² of GWR and MGWR improved by 0.05 and 0.07, respectively, and the RSS decreased by 210.13 and 179.95, respectively. ③ The results of MGWR regression showed that the spatial distribution of soil salinity appeared to be mainly affected by the middle soil salinity, soil clay content, and vegetation cover from the mean values of standardized regression coefficients of different influencing factors. Different influencing factors had significant spatial non-stationary characteristics on soil salinization. ④ The results of the spatial distribution prediction of soil salinity in MGWR showed that the areas of high soil salinity （≥6 g·kg^-1） were mainly distributed in the northern part of the study area, with an overall spatial trend of decreasing from the coast to the interior. The results of the study can be used as a reference for the analysis and predictive mapping of factors affecting soil salinization in the county and on a larger scale using MGWR.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634808","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 Long-term Fertilizations on the Organic Carbon Components of Soil Macroaggregates and the Yield of Wheat in Wheat Fields on the Loess Plateau].","authors":"Hong-Mei Song, Yu Gao, Ming-Xin Yun, Li Li, Xin-Ye Shi, Ting-Liang Li","doi":"10.13227/j.hjkx.202308046","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308046","url":null,"abstract":"<p><p>Soil macro-aggregates are the main location for soil organic carbon （SOC） sequestration, which is of great significance to improve soil fertility. This study aimed to understand the mechanisms of the organic carbon （OC） sequestration in macroaggregates and improve crop yield in wheat fields on the loess plateau. With the aggregate-density fractionation method, an eight-year experiment was conducted to investigate the following three factors： ① the effects of long-term fertilization on OC fractions within macroaggregates； ② the variation characteristics of OC fractions within macroaggregates, including coarse particulate organic carbon （cPOC）, fine particulate organic carbon （fPOC）, intra-microaggregate particulate organic carbon （iPOC）, free silt and clay particulate carbon （s+c_f）, and intra-microaggregate silt and clay particulate carbon （s+c_m）； ③ and the relationships between them and SOC input and yield formation. The treatments included no fertilization （CK）, farmer pattern （NP）, optimized fertilizers pattern （NPK）, optimized fertilizers + organic fertilizers pattern （NPKM）, and optimized fertilizers + biological organic fertilizers pattern （NPKB）. The results showed that the application of organic and chemical fertilizer （NPKM and NPKB） improved significantly the SOC content in macroaggregates compared with that in the single fertilizer treatment （NP and NPK）, which had a greater increase in SOC content in macroaggregates than that of the soil. All fertilization treatments had a tendency to increase the content of fractions iPOC, fPOC, and iPOC in macroaggregates, but silt and clay carbon （s+c_f and s+c_m） contents were decreased. The application of manure combined with chemicals markedly increased the allocations of fractions cPOC, fPOC, and iPOC reserves, but it greatly decreased （s+c_f） reserves allocation. However, the application of chemical fertilizers only significantly increased the proportion of cPOC reserves in macroaggregates. Correlation analysis showed that there were significant positive correlations among wheat grain yield and OC fractions （cPOC and fPOC） contents, SOC content, the OC content of &gt;0.25 mm macroaggregates, and SOC input, and the correlation coefficient was 0.645-0.883. In conclusion, long-term fertilization, especially combined with organic fertilizer, could promote the free silt and clay carbon fraction （s+c_f） to transfer into other forms of OC components through the increase in soil carbon input in the wheat field of the loess plateau. Furthermore, the OC content of macroaggregates was increased overall, providing a good soil environment for crop yield.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634801","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 Straw and Biochar Amendments on Characteristics of Soil Fungal Community and Organic Carbon Pool in <i>Jasminum sambac</i> Garden].","authors":"Jia-Hao Peng, Shao-Ying Lin, Wei-Qi Wang, Yu Zeng, Mei-Chun Chen, Wen-Wen Yang, Si-Cong Chen","doi":"10.13227/j.hjkx.202306194","DOIUrl":"https://doi.org/10.13227/j.hjkx.202306194","url":null,"abstract":"<p><p>In order to elucidate the changes in the soil fungal community and soil organic carbon components of a <i>Jasminum sambac</i> garden after straw and biochar application, we measured the organic carbon components and soil fungal community of the 0-15 cm soil layer in a <i>J. sambac</i> garden, which was divided into a control group, straw treatment group, and biochar treatment group. The carbon pool management index （CPMI） was also calculated. The results showed that the diversity of the soil fungal community was decreased after straw and biochar application, and the structure of dominant fungal genera was changed in each treatment. The soil fungal community structure in the biochar treatment was significantly different from that in the straw treatment and control groups. Redundancy analysis （RDA） showed that soil fungal community structure was mainly affected by soil bulk density, C∶N, salinity, and TN. Secondly, compared with that in the control group, soil labile organic carbon （LOC） in the straw treatment group was significantly increased by 87.44% （<i>P</i><0.05）, whereas soil dissolved organic carbon （DOC） and microbial biomass carbon （MBC） in the biochar treatment group were significantly increased by 22.27% and 23.17% （<i>P</i><0.05）, respectively. Further, compared with that in the control group, the carbon pool activity （<i>L</i>） under straw treatment was significantly increased （<i>P</i><0.05）, and the carbon pool index （CPI） under biochar treatment was significantly increased （<i>P</i><0.05）. Spearman correlation analysis showed that the distribution characteristics of soil organic carbon active components were regulated by the dominant fungi. FUNGuild functional prediction results showed that saprophytic and its facultative nutritional fungi had an important impact on soil organic carbon active components and carbon pool management index after straw and biochar application.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634803","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":"[Antibiotic Contamination Characteristics and Ecological Risk Assessment in Soils of Large-scaled Culturing Farms].","authors":"Jin Chen, Ya-Juan Wang, Hong Tao, Rui Zhagn","doi":"10.13227/j.hjkx.202308140","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308140","url":null,"abstract":"<p><p>The soils of different land use types in large-scaled culturing farms were collected for detecting the contents of antibiotics in these soils by applying high-performance liquid chromatography, analyzing the relationship between antibiotics and physicochemical properties of soils, as well as performing the ecological risk assessment of antibiotics in the soils of culturing farms by using the risk quotient method. The results showed that the surrounding soils of the culturing farm were contaminated by antibiotics to varying degrees, in which tetracycline had the highest detection rate and average content. Among the soils of different land use types, the average contents of antibiotics were ranked as corn field （1.48 μg·kg^-1）&gt;0.5 meters outside the farm fence （1.27 μg·kg^-1）&gt;yam field （1.03 μg·kg^-1）&gt;pasture （0.69 μg·kg^-1）&gt;woodland （0.18 μg·kg^-1）. According to the redundancy analysis results, the total nitrogen, total phosphorus, and cellulase had a great impact on the antibiotic content in soil samples. It can be concluded from the ecological risk assessment that oxytetracycline （OTC）, chlortetracycline （CTC）, doxycycline （DOC）, ciprofloxacin （CIP）, and tetracycline （TC） were categorized in the low risk level. Sulfadiazine （SM） and sulfadimidine （SM2） were categorized in the medium and high risk levels. It is of the upmost importance to control the antibiotic contamination in surrounding soils of culturing farms and to strengthen the management of veterinary antibiotics.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634771","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":"[Spatial and Temporal Scale Effects of Landscape Pattern on Riverine Nitrogen and Phosphorus Nutrients in the Qingshan Lake Watershed].","authors":"Jia-Ni Xu, Dong-Xin Liu, Sai-Yu Huang, Si-Qi Ni, Bing-Yan Li, Sheng-Jia He, Jian-Hong Wu, Pei-Kun Jiang","doi":"10.13227/j.hjkx.202307244","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307244","url":null,"abstract":"<p><p>The influences of landscape pattern on water quality are dependent on spatial-temporal scales. However, the effects of landscape composition, landscape configuration, and landscape slope metrics on seasonal water quality at different spatial scales remain unclear. Based on the total nitrogen, total phosphorus, nitrate-N, and ammonium-N data from 26 sampling sites in the Qingshan Lake watershed, this study coupled landscape pattern analysis, redundancy analysis, and partial redundancy analysis to quantify the spatiotemporal scale effects of landscape pattern on riverine nitrogen （N） and phosphorus （P） concentrations. The results showed that： ① The explanatory ability of landscape pattern at the sub-watershed scale on riverine N and P concentrations was 6.8%-8.4% higher than that at the buffer scale, and this effect was more obvious in the dry season. ② At the sub-watershed scale, the percentage of forestland and the interspersion and juxtaposition degree of residential land had a greater influence on riverine N and P concentrations. At the buffer scale, the slope of farmland and residential land and the aggregation degree of forestland patches were the key factors affecting riverine N and P concentrations. ③ The contribution rate of landscape configuration to riverine N and P concentration variations （20.1%-36.5%） was the highest. The sensitivity of the effect of landscape configuration on riverine N and P concentrations to seasonal changes was the highest, and the effect of landscape slope on riverine N and P concentrations had the highest sensitivity to spatial scale changes. Therefore, landscape pattern-regulated non-point source pollution should be considered from a multi-scale perspective. These results can provide scientific basis for the formulation of landscape pattern optimization measures aiming at non-point source pollution control.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634831","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":"[Estimation of Near-surface Ozone Concentration in the Beijing-Tianjin-Hebei Region Based on XGBoost-LME Model].","authors":"De-Cai Gong, Ning Du, Li Wang, Xian-Yun Zhang, Long Li, Hong-Fei Zhang","doi":"10.13227/j.hjkx.202307110","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307110","url":null,"abstract":"<p><p>High spatiotemporal resolution data on near-surface ozone concentration distribution is of great significance for monitoring and controlling atmospheric ozone pollution and improving the living environment. Using TROPOMI-L3 NO₂, HCHO products, and ERA5-land high-resolution data as estimation variables, an XGBoost-LME model was constructed to estimate the near-surface ozone concentration in the Beijing-Tianjin-Hebei Region. The results showed that： ① Through correlation analysis, surface 2 m temperature （T2M）, 2 m dewpoint temperature （D2M）, surface solar radiation downwards （SSRD）, tropospheric formaldehyde （HCHO）, and tropospheric nitrogen dioxide （NO₂） were important factors affecting the near-surface ozone concentration in the Beijing-Tianjin-Hebei Region. Among them, T2M, SSRD, and D2M had strong correlations, with correlation coefficients of 0.82, 0.75, and 0.71, respectively. ② Compared with that of other models, the XGBoost-LME model had the best performance in terms of various indicators. The ten-fold cross-validation evaluation indicators <i>R</i>², MAE, and RMSE were 0.951, 9.27 μg·m^-3, and 13.49 μg·m^-3, respectively. At the same time, the model performed well at different time scales. ③ In terms of time, there was a significant seasonal difference in near-surface ozone concentration in the Beijing-Tianjin-Hebei Region in 2019, with the concentration changing in the order of summer &gt; spring &gt; autumn &gt; winter. The monthly average ozone concentration in the region showed an inverted \"V\" trend, with a slight increase in September. The highest value occurred in July, whereas the lowest value occurred in December. In terms of spatial distribution, the near-surface ozone concentrations in the Beijing-Tianjin-Hebei Region during the months of February and March were generally at the same levels. In January, November, and December, there was a relatively insignificant trend of higher concentrations in the north and lower concentrations in the south. For the remaining months, the spatial distribution of near-surface ozone concentrations in this area predominantly exhibited a pattern of higher concentrations in the south and lower concentrations in the north. High-value areas were predominantly found in the plain regions of the southern part with lower altitudes, dense population, and higher industrial emissions； low-value areas, on the other hand, were primarily located in mountainous areas of the northern part with higher altitudes, sparse population, higher vegetation coverage, and lower industrial emissions.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634806","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}