工业工程最新文献

{"title":"[Differentiation Impact of Urban Form on Heat Island Intensity Along Urban Development Gradients in Zhengzhou].","authors":"Sen Wang, Sui-Ping Zeng, Jun-Mo Lu, Namaiti Aihemaiti, Jian Zeng","doi":"10.13227/j.hjkx.202403029","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403029","url":null,"abstract":"<p><p>The impact mechanism of urban form on heat island intensity （HI） is a core issue of research attention. Existing achievements have mostly focused on the correlation between urban form and thermal environment. Research on the differences along urban development gradients, and research on marginal effects and optimization paths under gradient differences is relatively scarce. This study considered the central urban area of Zhengzhou as an example, based on multi-source data such as Landsat remote sensing images and NPP-VIIRS satellite night light remote sensing images, and introduced a gradient-enhanced regression tree model to improve the DEMATEL-ISM method, exploring the gradient differences and marginal effects of urban morphology on heat island intensity. The results showed that： ① From 2006 to 2020, the HI decreased with the increase in urban development gradient, and the increasing trend slowed down annually. ② The gradient difference between urban form and HI was significant. The green space form index always had a strong impact on HI, among which, NDVI was the most significant variable within each gradient, and the impact intensity of the construction land pattern index increased significantly with the increase in gradient, whereas the role of building combination form index weakened accordingly. ③ According to the ISM model, a four story-three order structural model of urban form indicators was obtained. The construction land pattern indicator within the high intensity construction gradient was the root cause order, and the building combination form indicator within the low intensity construction gradient was the root cause order. ④ The differences in the marginal effect of urban form along the gradient were significant. As the value of the indicator increased, its impact intensity and direction would change. There were differences in the key indicators and threshold ranges that affected the intensity of HI within different gradients. The study proposes a marginal optimization method for urban form based on the improvement of the urban thermal environment under the differences along urban development gradients, providing refined practical reference for orderly urban expansion and coordinated urban-rural development.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1924-1936"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671217","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 Different Metal Elements on Cadmium Uptake Under Wheat-rice Rotation Condition].","authors":"Jing Tian, Zhen-Bo Wang, Jian-Kang Zhou, Hai-Kuan Cheng, Chang Li, Hong-En Liu, Fu-Qing Sui, Peng Zhao","doi":"10.13227/j.hjkx.202403038","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403038","url":null,"abstract":"<p><p>The accumulation of cadmium （Cd） in the food chain poses a serious threat to human health. To explore the possible heavy metal cation inhibitor, a pot experiment was developed to research the addition of Fe, Mn, Zn, and Mg on Cd uptake and accumulation in wheat and rice. Soil Cd content was artificially added to 5 mg·kg^-1 and aged for one month. Fe, Mn, and Zn were added as metal chlorides at a ratio of 100 mg·kg^-1 and Mg for 300 mg·kg^-1. The main results were： ① Zn supplementation significantly enhanced the grain biomass of wheat and rice； ② Zn remarkably reduced the grain Cd content in wheat and rice, with a decrease of 41% and 23% in wheat and rice grain Cd content compared with that in the control, respectively, without yield penalty； and ③ In the wheat-rice rotation mode, the grain Cd content in rice was notably lower than that in wheat, with a reduction to 0.17 mg·kg^-1 for <i>ω</i> （Cd）, which was below the rice Cd limit value （0.2 mg·kg^-1） specified by the national food safety standard （GB 2762-2022）. Collectively, these findings suggest that the application of Zn in a wheat-rice rotation system significantly mitigate Cd accumulation in grains, with rice exhibiting a more pronounced effect. These results hold notable implications for the safe utilization of Cd-contaminated farmland and ensuring food security.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1806-1814"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671241","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":"[Influencing Factors and Decoupling Effects of Agricultural Carbon Emissions in the Yangtze River Economic Belt].","authors":"Yu-Liang Cao, Xun Ni, Hong-Yu Gong","doi":"10.13227/j.hjkx.202403263","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403263","url":null,"abstract":"<p><p>In the context of the era when new quality productivity is promoting the construction of an agricultural power, sorting out the rising path of agricultural carbon in the Yangtze River Economic Belt and clarifying issues, such as agricultural carbon height and carbon decoupling are important to promoting the \"double carbon\" process in the agricultural field. A statistical model of agricultural carbon emissions was established to measure the agricultural carbon emissions of 11 provinces （municipalities） in the Yangtze River Economic Belt from 2000 to 2022. On the basis of clarifying the spatial and temporal distribution characteristics and reduction of agricultural carbon emission intensity, the LMDI model was used to analyze agricultural carbon emissions. Second, we constructed models of decoupling in terms of speed and quantity and explored the decoupling relationship between the most influential factors with the strongest driving effect and agricultural carbon emissions. The results showed that during the study period, the total agricultural carbon emissions in the Yangtze River Economic Belt first increased and then decreased, and the major emission sources were straw burning, grain planting, livestock breeding, and agricultural material input. The level of economic development was the major factor leading to the increase in agricultural carbon emissions. Although the improvement of agricultural production efficiency inhibited the increase in carbon emissions caused by the growth of output value to a certain extent, the total inhibitory effect was lesser than the total promotion effect. From the perspective of double decoupling, the region has not yet reached a stable and strong decoupling state between agricultural carbon emissions and economic income growth of farmers. Based on this, suggestions for pollution reduction and carbon sequestration, clean production, and green transformation are put forward, respectively, for the planting industry, breeding industry, and agricultural product supply chain in the upstream, midstream, and downstream regions.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1535-1547"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671306","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 Microbial Community Structure in Long-term Polycyclic Aromatic Hydrocarbon-contaminated Soil].","authors":"Yang-Yang Jiao, Ting Wu, Rui Li, Gao-Peng Bian, Hai-Hua Jiao, Zhi-Hui Bai","doi":"10.13227/j.hjkx.202401153","DOIUrl":"https://doi.org/10.13227/j.hjkx.202401153","url":null,"abstract":"<p><p>Characterizing the structure of soil microbial communities in natural habitats chronically contaminated with polycyclic aromatic hydrocarbons （PAHs） contributes to the understanding of potential risks and changes in ecological functions of contaminated soils. Microorganisms are facilitators of material cycling and functional stability in soil ecosystems. Few studies are available on the microbial community structure of soil contaminated with long-term high concentrations of PAHs. In this study, we investigated the effects of PAHs on soil microbial community structure in natural habitats using field surveys and high-throughput sequencing analysis of 16S rRNA genes in agricultural soils contaminated with PAHs around a coking plant in Shanxi. The results showed that soil microorganisms were diverse （40 phyla, 769 genera, and 1610 species）. Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, and Gemmatimonadetes were the dominant taxa, with a total abundance of 79.8%. No obvious dominant taxa was observed at the genus and species levels. Electrical conductivity （EC）； pH； total organic matter （TOC）； total potassium （TK）； fast-acting potassium （AK）； and Dibenzo（a,h）anthracene （DaA）, Benzo（a）anthracene （BaA）, and Anthracene （Ant） were the first drivers of the microbial community （<i>R</i>²≥ 0.10）. Soluble phosphorus （AP）； fast-acting nitrogen （AN）； and Acenaphthylene （Acy）, Benzo（b）fluoranthene （BbF）, Fluoranthene （Fla）, and Pyrene （Pyr） were the second drivers （0.05 ≤ <i>R</i>² &lt; 0.10）. Total nitrogen （TN）； total phosphorus （TP）； and Phenanthrene （Phe）, Benzo（a）pyrene （BaP）, Chrysene （Chry）, Benzo（k）fluoranthene （BkF）, and Indeno（1,2,3-cd）pyrene （InP） were the third driving factors （<i>R</i>² &lt; 0.05）. The study will provide some theoretical basis for the research of ecological risk management and microbial remediation technology of PAHs-contaminated soil.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1885-1896"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671093","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 Organic Materials Applied to Saline Soil on Crop Growth and Soil Saline-alkali Index].","authors":"Xiao-Juan Yang, Hao He, Li-Yang Cheng, Xiang-Jie Chang, Shuai Li, Meng-Meng Yu, Bin-Quan Wang, Jun-Hua Li","doi":"10.13227/j.hjkx.202403269","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403269","url":null,"abstract":"<p><p>To provide a theoretical basis for the scientific application of organic materials in salinized soil and the improvement of soil quality and to explore the response phenotype of an organic material-salinized soil-plant system, the salinized soil in Xinjiang was considered as the research object, and cotton, rape, and oil sunflower were considered as the test crops. Six treatments, including the control group, microbial agent, humic acid, organic fertilizer, biochar, and straw, were set up for indoor culture experiments. The effects of different organic materials on the growth of cotton, oil sunflower, and rape crops and soil saline-alkali indexes under moderate salinization soil conditions were analyzed, and the combinations with certain improvement effects were screened out. This provided a certain experimental basis for the application and promotion of organic materials in Xinjiang. The results showed that, compared with that under the control treatment, the application of the microbial inoculant, organic fertilizer, and biochar had a significant effect on crop growth. At 60 d of emergence, the dry weight of cotton after the application of the microbial inoculant, organic fertilizer, and biochar increased by 41%, 43%, and 25%, respectively. The dry weight of oil sunflower increased by 5%, 13%, and 27%, respectively. The dry weight of rape increased by 113%, 104%, and 83%, respectively. After the application of organic fertilizer and biochar, the emergence rate of cotton and rape increased by 14.3% and 10.2%, respectively, and 26.50% and 20.82%, respectively. Taking the results of the soil salt-alkali index analysis at 60 d after seedling emergence as an example, the application of the microbial agent and straw had no significant effect on the total amount of water-soluble salt in the soil, whereas the application of humic acid, organic fertilizer, and biochar increased the total amount of water-soluble salt in the soil. The application of the microbial agent and straw could reduce soil pH, and the application of humic acid and biochar could increase soil pH. Soil electrical conductivity of all organic materials increased and humic acid treatment increased the most significantly. The effect of the microbial agent and straw treatment on soil alkalinity was the best, whereas the other treatments showed no significant difference. Straw could reduce soil sodium adsorption ratio, and humic acid and organic fertilizer could increase the soil sodium adsorption ratio. In summary, it is recommended to apply microbial agents, organic fertilizers, and biochar to saline soil for the purpose of promoting crop growth, and to apply a microbial agent and straw to saline soil for the purpose of improving soil quality.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1751-1761"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671175","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":"[Impacts of Online Measurements of Organic Molecular Markers as Input Species for PM_2.5 Source Apportionments: A Case Study in Hangzhou During the 19^th Asian Games].","authors":"Shu-Hui Zhu, Cong-Yan Huang, Yong Lai, Yu-Hang Wu, Ren-Chang Yan, Jian-Dong Shen, Jun-Jie Tian, Ya-Qin Gao, Ying-Ge Ma","doi":"10.13227/j.hjkx.202404043","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404043","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Positive matrix factorization （PMF） is one of the most widely used receptor models for PM&lt;sub&gt;2.5&lt;/sub&gt; source apportionment. The traditional PMF method generally uses inorganic （such as nitrate, sulfate, and EC） measurement data as input species to apportion PM&lt;sub&gt;2.5&lt;/sub&gt; sources. These species have ambiguous source origins； thus quantifying PM&lt;sub&gt;2.5&lt;/sub&gt; sources with high source sectors is difficult. In this study, online measurements of major chemical components, elemental tracers, as well as organic molecular markers were applied in a PMF model to investigate the differences between the major chemical components-based PMF （MCC） and organic molecular markers-based PMF （OMM） methods in terms of source identification, source separation, and source quantification. The results showed that with the input of organic molecular markers （such as polycyclic aromatic hydrocarbons, fatty acids, dicarboxylic acids, hydroxyl-dicarboxylic acids, C&lt;sub&gt;9&lt;/sub&gt; acids, and phthalic acid）, the OMM method greatly enlarged the number of source factors identified. Further, industry emission, shipping emission, dust, vehicle emission, biomass burning, secondary nitrate, and secondary sulfate； two primary source factors （coal combustion and cooking emission）； and four secondary organic aerosol （SOA） source factors were also resolved in the OMM method. Comparing with the source profiles resolved by the MCC method, we found that OC/EC mass ratios in OMM-resolved source profiles of industry emission, vehicle emission, biomass burning, and coal combustion were closer to those obtained from emission inventories. In terms of source quantification, the mass contributions of vehicle emission and biomass burning resolved by the MCC method were notably higher than those resolved by the OMM method, especially under high O&lt;sub&gt;3&lt;/sub&gt; concentrations （&gt; 120 μg·m&lt;sup&gt;-3&lt;/sup&gt;）. This suggests that without the input of specific organic molecular markers, the MCC method was inclined to apportion parts of secondary source contributions into primary sources （such as vehicle emission and biomass burning）. We further quantified and compared PM&lt;sub&gt;2.5&lt;/sub&gt; source contributions in Hangzhou before, during, and after the 19&lt;sup&gt;th&lt;/sup&gt; Asian Games with the application of the OMM method. Our results showed that the percentage contributions of vehicle emission, industry emission, and dust dropped by 65%, 24%, and 24%, respectively, during the Games. Anthropogenic SOA and aged SOA also displayed significant decreases in mass contributions during the Games by 35% and 49%, respectively, due to the emission reduction of volatile organic compounds （VOCs）. These results imply that PM&lt;sub&gt;2.5&lt;/sub&gt; pollution can be effectively controlled with the implementation of emission reduction measures. Our study also revealed that online measurements of organic molecular markers are important for improving PM&lt;sub&gt;2.5&lt;/sub&gt; source apportionment results and formulating pollution control policie","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1314-1325"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671304","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":"[Soil Carbon Restoration and Its Influencing Factors in Coal Mining Areas of Yellow River Basin: A Meta-analysis].","authors":"Hong-Wei Sun, Mei-Fang Yan","doi":"10.13227/j.hjkx.202401155","DOIUrl":"https://doi.org/10.13227/j.hjkx.202401155","url":null,"abstract":"<p><p>Coal mining has caused notable disturbance and destruction to the ecosystem, leading to intensified regional carbon emissions. Ecological restoration of abandoned coal mines can improve the physical and chemical properties of damaged soil and increase soil carbon storage. Therefore, ecological restoration of coal mine areas is crucial for improving regional carbon sink levels and environments. Currently, most studies on ecological restoration in Chinese coal mining areas are scattered across the major coal-producing provinces in the Yellow River Basin. Its effect on soil carbon sequestration at a basin scale must be crucially elucidated. In this study, we focused on changes in soil physicochemical properties and enzyme activities after vegetation restoration using an integrated analysis method, combined with climate and soil characteristics in the Yellow River Basin's coal mining areas to reveal the major factors affecting soil carbon restoration. Our results showed that： ① Soil physicochemical properties and enzyme activities were improved significantly after ecological restoration； however, some differences were present among different soil layers. ② Soil organic carbon （SOC）, total nitrogen, and alkali-hydrolyzed nitrogen increased by 62.2%, 40.5%, and 36.0%, respectively, showing an overall increasing trend with increasing restoration years. From the perspective of vegetation type, mixed forest had the largest increment in SOC. ③ The increase in nitrogen and phosphorus content improved soil fertility and helped to increase soil carbon input from vegetation litter, thus promoting the restoration of the soil organic carbon pool. In addition, average annual temperature and precipitation along with soil type also played important roles affecting soil C restoration. In the future, based on climate and soil characteristics of specific mining areas, suitable vegetation types should be selected from a perspective of C sequestration to enhance C sink of the whole basin.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1690-1702"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671337","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 and Simulation of Ecological Vulnerability in Qinghai-Xizang Plateau Nature Reserve].","authors":"Xiao-Feng Wang, Yuan-Yuan Zheng, Ze-Chong Sun, Ji-Tao Zhou, Xiao-Xue Wang, Meng-Na Zhu","doi":"10.13227/j.hjkx.202403096","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403096","url":null,"abstract":"<p><p>The Qinghai-Xizang Plateau is the largest ecologically fragile and sensitive area in China and clarifying the spatial and temporal characteristics of ecological vulnerability of the Qinghai-Xizang Plateau Nature Reserve is important to promote the synergistic enhancement of the ecological security barrier and green development. Taking the Qinghai-Xizang Plateau Nature Reserve as a case study, we constructed a system of evaluation indicators and quantitatively evaluated the spatial and temporal characteristics based on the three dimensions of sensitivity-importance-resilience （SIR）. We also simulated the scenarios of ecological vulnerability under different decision-making preferences by using AHP-OWA. The results showed that： ① From 2000 to 2020, the ecological vulnerability index （EVI） of the Qinghai-Xizang Plateau decreased from 0.79 to 0.74, and the ecological vulnerability pattern of the nature reserves showed a trend of improvement； however, the higher vulnerability areas were still dominant. ② The spatial pattern of ecological vulnerability showed a general pattern of \"high in the northwest and low in the southeast,\" with the high values mainly concentrated in the northwest and low values in the southeast. The high values were mainly concentrated in Qiangtang, Cocozily, Zhongkunlun, and Arjinshan, and the low values were located in the southeast of Yarlung Zangbo River and Ruoergai Wetland Nature Reserve. ③ Based on the OWA method, three scenarios were set up, from the sustainability-oriented to the economy-priority oriented, and the scope of the highly fragile area was expanding, with the Qiangtang and Arjinshan regions being more obvious, and the changes in the low fragile area being lesser. This study assessed the ecological vulnerability of the Qinghai-Xizang Plateau Nature Reserve and simulated the future scenarios of vulnerability under different development conditions through the OWA method, which can provide theoretical references for the construction of regional sustainable development and vulnerability risk early warning mechanisms.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1633-1644"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671092","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 the Source and Spatiotemporal Variation of Dissolved Organic Matter in the Chaohe River Watershed].","authors":"Zhuo-Ni Ma, Chun-Zi Guo, Hao Zhang, Shuang Song, Yao-Qi Gong, Chen-Yang Shou, Fu-Jun Yue","doi":"10.13227/j.hjkx.202404106","DOIUrl":"https://doi.org/10.13227/j.hjkx.202404106","url":null,"abstract":"<p><p>Dissolved organic matter （DOM） is widespread in aquatic environments and plays a crucial role in various biogeochemistry processes. Urbanization and anthropogenic activities have significantly altered the source and characteristics of DOM in rivers. Therefore, analyzing the spatial and temporal variation of DOM on a watershed scale to trace its source for effective water quality management is important. In this study, the composition characteristics of DOM in the Chaohe River watershed, which is the source of drinking water in northern China, were analyzed using the EEM-PARAFAC method. Furthermore, the source of DOM was further identified by analyzing the relationships among optical parameters. The results revealed the four components in DOM： component 1 resembled fulvic acid, while component 2 and component 4 exhibited characteristics similar to those of humic compounds. Component 3 displayed tryptophan-like acidity, with the highest intensity observed during both high and low flow periods. Temporal and spatial variation in fluorescence parameters further indicated a distinct source of DOM across the three water periods. Notably, non-point source pollution was prominent during the low water period, whereas soil-related characteristics dominated during the flood season. Spatial analysis revealed that under natural vegetation cover, terrestrial detritus significantly influenced DOM originating from the source area. However, urbanization-induced anthropogenic pollution had become more pronounced in the middle reaches. Additionally, the downstream area with extensive aquatic vegetation coverage experienced notable impacts from phytoplankton proliferation. Correlation analysis demonstrated varying degrees of association between water environmental parameters, nitrogen and phosphorus content, optical parameters, and DOM across three hydrological periods. These findings revealed that water environment dynamics and nutrient sources govern the temporal and spatial distribution patterns of DOM.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1395-1405"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671133","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":"[Effect of Low-density Polyethylene Microplastics on Soybean-soil-microbial System].","authors":"Yu-Fei Jia, Jia-Wen Wang, Rui-Kun Wang, Tian-Qi Wang, Xue-Hui Xu","doi":"10.13227/j.hjkx.202403213","DOIUrl":"https://doi.org/10.13227/j.hjkx.202403213","url":null,"abstract":"<p><p>The widespread use of plastics has led to the prevalence of microplastics in the soil environment, which, as an emerging pollutant, affects plant growth, soil physicochemical properties, and microbial community structure. The effects of different contents of low-density polyethylene microplastics （LDPE-MPs） on soybean growth, soil physicochemical properties, soil enzyme activities, and microbial activities were investigated through pot culture experiments to explore the toxic effects of microplastics on soybean-soil-microbial systems. The results showed that compared with that in the control, microplastics inhibited soybean emergence （14.1%-25.0%）, whereas plant height, biomass, and pod weight were inhibited by low concentration and promoted by high concentration, and SPAD of soybean was significantly reduced by high concentrations of microplastics stress. Microplastics affected the quality of soybeans, with s-sugars, s-proteins, and cellulose increased by 117.7%-258.8%, 3.7%-61.6%, and 47.8%-83.4%, respectively, compared with those in the control. Microplastic addition also affected soybean nutrient uptake, as evidenced by the promotion of N （95.1%-144.4%） and P （4.1%-20.4%） uptake in the above-ground portion of soybeans and N （11.4%-19.4%） and P （8.5%-42.6%） uptake in the below-ground portion of soybeans, and inhibited K （2.2%-15.3%） uptake in the aboveground portion of the plant and K （3.9%-9.4%） uptake in the below-ground portion of the plan, respectively. The addition of microplastics had little effect on soil pH； however, it significantly increased CEC （65.1%-74.7%） and SOM （22.6%）. With the increase in the addition content, the content of NO₃^--N, AP, AK, and UE activities were significantly reduced； the content of NO₃^--N, AP, and AK was reduced by 57.7%, 22.0%, and 18.8% compared with that in the control at 3% addition, respectively； and UE activity was inhibited by 13.98%. Further, 16S rRNA sequencing analysis showed that microplastic stress increased the abundance of the Proteobacter group and reduced the abundance of the Acidobacter group in the soil, decreasing the diversity of the community, which in turn destabilized the microbial community and made the entire system less stable. In summary, microplastic stress affects the stability of soybean-soil-microbial systems.</p>","PeriodicalId":35937,"journal":{"name":"环境科学","volume":"46 3","pages":"1831-1840"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671233","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}