urbanization

城市化
  • 文章类型: Journal Article
    UNASSIGNED: As China has undergone the processes of urbanization and economic development, a large migrant population has emerged, creating new family migration trends. Family migration brings about changes in urban integration costs and benefits, affecting health investment.
    UNASSIGNED: The primary objective of this research is to investigate the influence of urban integration of migrant workers\' families on their mental wellbeing, with the aim of offering policy recommendations conducive to the realization of a comprehensive public health strategy in China.
    UNASSIGNED: This paper uses multi-dimensional indexes to measure family urban integration, covering economic, social and psychological dimensions, which may consider the complexity of integration. Utilizing a machine learning clustering algorithm, the research endeavors to assess the level of urban integration experienced by migrant workers and their respective families. The analysis discerns three distinct clusters denoting varying degrees of urban integration within these familial units, namely high-level, medium-level, and low-level urban integration. We applied binary logit regression models to analyze the influence of family urban integration on the mental health among migrant workers. Then we conducted a series of robustness tests.
    UNASSIGNED: The results show that family urban integration decreases the probability of depressive symptoms by 14.6 percentage points. Further mechanism tests show that family economic integration enhances the psychological wellbeing of migrant workers by elevating their income status. Family social integration decreases depressive symptoms by increasing social status. Family psychological integration increases the psychological health of migrant workers by making them more satisfied with their lives. The heterogeneity test shows that family urban integration and its different dimensions have a strong impact on the depressive symptoms of women, first-generation, and less-educated groups.
    UNASSIGNED: This study finds that family urban integration and its economic, social, and psychological dimensions significantly reduced the depressive symptoms of migrant workers. The results of this study lead the authors to recommend formulating a family-centered policy for migrant workers to reside in urban areas, optimizing the allocation of medical resources and public services, and improving family urban integration among migrant workers in order to avoid mental health problems in the process of urban integration.
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  • 文章类型: Journal Article
    背景:高血压(HBP)和糖尿病(DM)是全球最常见的两种心血管疾病,特别是在社会经济地位较低的个人中。研究已经将住宅绿色与降低HBP和DM的风险联系起来。然而,关于SES是否可以改变住宅绿色与HBP和DM的关联的证据有限。
    方法:基于一项针对44,876名成年人的全国代表性横断面研究,我们以1km的空间分辨率生成了归一化植被指数(NDVI),以表征个体的住宅绿色水平。行政分类(城市/农村),夜光指数(NLI),个人收入,和教育水平被用来表征区域城市化和个人SES水平。
    结果:我们观察到与城市地区相比,农村地区NDVI与HBP和DM的负相关较弱。例如,以及每四分位数范围(IQR,0.26)住宅NDVI增量为0~5年移动平均线,农村地区HBP的OR为1.04(95CI:0.94,1.15),城市地区HBP的OR为0.85(95CI:0.79,0.93)(P=0.003).随着NLI水平的下降,NDVI与DM患病率呈负相关(P<0.001).此外,在收入较低且受教育程度较低的人群中,居民NDVI与HBP和DM患病率的负相关较弱.
    结论:较低的地区城市化程度和个体SES可以减弱住宅绿色与HBP和DM患病率的关联。
    BACKGROUND: High blood pressure (HBP) and diabetes mellitus (DM) are two of the most prevalent cardiometabolic disorders globally, especially among individuals with lower socio-economic status (SES). Studies have linked residential greenness to decreased risks of HBP and DM. However, there has been limited evidence on whether SES may modify the associations of residential greenness with HBP and DM.
    METHODS: Based on a national representative cross-sectional study among 44,876 adults, we generated the normalized difference vegetation index (NDVI) at 1 km spatial resolution to characterize individuals\' residential greenness level. Administrative classification (urban/rural), nighttime light index (NLI), individual income, and educational levels were used to characterize regional urbanicity and individual SES levels.
    RESULTS: We observed weaker inverse associations of NDVI with HBP and DM in rural regions compared to urban regions. For instance, along with per interquartile range (IQR, 0.26) increment in residential NDVI at 0∼5 year moving averages, the ORs of HBP were 1.04 (95%CI: 0.94, 1.15) in rural regions and 0.85 (95%CI: 0.79, 0.93) in urban regions (P = 0.003). Along with the decrease in NLI levels, there were continuously decreasing inverse associations of NDVI with DM prevalence (P for interaction <0.001). In addition, weaker inverse associations of residential NDVI with HBP and DM prevalence were found among individuals with lower income and lower education levels compared to their counterparts.
    CONCLUSIONS: Lower regional urbanicity and individual SES could attenuate the associations of residential greenness with odds of HBP and DM prevalence.
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  • 文章类型: Journal Article
    公平有效地规划城市公园绿地是促进城市绿色健康发展、提高市民生活质量的重要途径。然而,在快速城市化的背景下,线性大城市,以其独特的空间形态和高密度的人口聚集,给城市公共绿地的规划和管理带来了特殊的挑战。本研究以兰州,中国高密度线性大城市的典型代表,作为一个案例研究。在改进传统高斯两步浮动集水面积法(G2SFCA)的基础上,结合基尼系数和洛伦兹曲线,在城市和地区尺度上评价了兰州中心城区UPGS供需的社会公平性和空间公平性。同时,UPGS供需短缺的区域被准确地确定为未来优化的关键区域。结果表明:(1)线性大兰州UPGS供需公平性在社会和空间层面存在显著差异,大多数UPGS资源为少数人所享有;(2)UPGS的空间可达性具有明显的“串珠”分布特征,可达性较高的地区主要集中在河流沿线;(3)UPGS供需公平性表现出空间梯度效应,其特征是圆形分布。从里到外,它如下:良好的供应密集的人口,良好的供应-人口稀疏,供应短缺-人口密集,供应短缺-人口稀少。最后,基于“渐进式微再生”的概念和位置分配模型(LA),确定了新UPGS的最佳站点,UPGS供需公平最大化。这为相关管理部门今后优化园区布局提供了实践参考。
    Equitable and effective planning of urban park green spaces (UPGSs) is an important way to promote green and healthy urban development and improve citizens\' quality of life. However, under the background of rapid urbanization, linear large cities, with their unique spatial forms and high-density population agglomerations, have brought special challenges for the planning and management of urban public green spaces. This study takes Lanzhou, a typical representative of high-density linear large cities in China, as a case study. Based on the improvement of the traditional Gaussian Two-Step Floating Catchment Area method (G2SFCA), combined with the Gini coefficient and the Lorentz curve, the social equity and spatial equity of UPGS supply-demand in the central urban area of Lanzhou were evaluated at the city and district scales. Meanwhile, the areas with shortage of UPGS supply-demand were accurately identified as the key areas for future optimization. The results show that: (1) There are significant differences in the equity of UPGS supply-demand in the linear large Lanzhou at the social and spatial levels, and most UPGS resources are enjoyed by a few people; (2) The spatial accessibility of UPGSs has an obvious \"string of beads\" distribution Characteristics, and the areas with high accessibility are mainly concentrated along rivers; (3) The equity of UPGS supply-demand exhibits a spatial gradient effect, which is characterized by a circle distribution. From the inside to the outside, it is as follows: good supply-dense population, good supply-sparse population, supply shortage-dense population, supply shortage-sparse population. Finally, based on the concept of \"progressive micro-regeneration\" and the Location Allocation model (LA), the optimal sites for new UPGSs were determined, maximizing the equity of UPGS supply-demand. This provides a practical reference for relevant management departments to optimize park layouts in the future.
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  • 文章类型: Journal Article
    Understanding the responses of ecosystem service trade-offs and synergies in metropolitan areas to the multidimensional expansion of urban space is of great significance for the optimization of regional land spatial pattern and high-quality development. With the Guangfo Metropolitan Area as research region, we used land use data and natural ecological environment data from 2000 to 2020 to measure the expansion characteristics of urban space in the dimensions of scale, distribution, and morphology by using the landscape pattern indices. We further calculated four main ecosystem services: urban cooling, habitat quality, recreation, and water conservation by the InVEST model, quantified the trade-off and synergistic relationship of multiple ecosystem services by the coupling coordination degree model, and explored its response to multidimensional urban spatial expansion by using the multi-scale geographically weighted regression model. The results showed that urban land use scale in the Guangfo Metropolitan Area continued to increase from 2000 to 2020, with an accelerated growth rate from 2010 to 2020. The ave-rage patch area of urban land in the central area and the urban land of small patches in the northeast increased, evolving from a \"dual-center\" structure to a \"single-center\" one. The distance between urban land patches in the Guangfo Metropolitan Area was relatively small, indicating a compact distribution of urban land. The distance between newly developed urban land patches was also small, but had gradually increased in recent years. The patch shape of urban land was relatively regular and less complex, but the complexity of the newly added urban land gra-dually increased. The ecosystem service trade-offs and synergies in the Guangfo Metropolitan Area had undergone significant changes, with a decrease in synergies and an increase in trade-off, and extreme trade-offs had gradually become dominant. The response of ecosystem services synergies to changes in urban land use scale was the most intense and had spatial heterogeneity, while the response to the change of distribution and morphological characte-ristics of urban land showed periodic differences.
    研究都市圈生态系统服务权衡协同关系对城镇空间扩张的响应,对区域城镇空间格局优化和高质量发展具有重要意义。本研究以广佛都市圈为研究区域,基于2000—2020年土地利用数据及自然生态环境等相关数据,选取景观格局指数测度城镇空间的规模、分布、形态维度的扩张特征,利用InVEST模型计算降温服务、生境质量、自然游憩和水源涵养4项主要生态系统服务,采用耦合协调度模型量化多元生态系统服务间的权衡协同关系,并通过多尺度地理加权回归模型探究其对城镇空间多维扩张的响应。结果表明:2000—2020年,广佛都市圈城镇用地规模持续增加,且2010—2020年间的增速加快,中心区城镇用地平均斑块面积增加和东北部小斑块的城镇用地增加,都市圈由“双中心”向“单中心”演化。广佛都市圈城镇用地斑块间距离较小,分布较为紧凑,新增城镇用地间距离较小,但近年来逐渐增大。城镇用地斑块形态整体较规整,复杂度较小,新增城镇用地的形态复杂度逐渐增加。广佛都市圈生态系统服务权衡协同关系变动较为剧烈,协同关系减少,权衡关系增加,且极度权衡关系逐渐占主导地位。广佛都市圈生态系统服务协同对城镇用地规模变化的响应最剧烈且具有空间异质性,对城镇用地分布和形态变化的响应存在阶段性差异。.
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  • 文章类型: Journal Article
    地质条件复杂,再加上城市扩张,资源消耗,经济快速发展,使重庆中心城区的生态环境更加脆弱。增强本地区资源环境承载能力,科学评估重庆市生态风险变化趋势具有重要意义。建立了重庆市生态风险评价指标体系,利用“压力-状态-响应”框架。熵权法(EWM)用于为每个变量分配权重,建立灰色加权聚类评价模型(GWCEM)。对重庆市9个中心城区2005-2021年的生态风险进行了评价,并对2022-2025年的生态风险水平及变化进行了预测。研究表明,重庆市生态风险影响因子的综合排序顺序为:响应因子>压力因子>状态因子。在整个研究期间,我们观察到巴南的生态风险值下降,沙坪坝,九龙坡,南安区和渝北区占50%以上。这些下降速度正在加快,生态风险水平的区域差异正在缩小。从2022年到2025年,除了沙坪坝,江北,玉中,南安区始终保持“低风险”水平,所有其他地区的生态风险水平继续下降,到2025年与“低风险”分类保持一致。根据生态风险评价和生态风险等级预测结果,对重庆市中心城区生态环境保护和生态风险管理提出了相应的建议。
    Complex geological conditions, coupled with urban expansion, resource consumption, and rapid economic development, make the ecological environment of Chongqing\'s central urban area more vulnerable. To enhance the carrying capacity of resources and the environment in this region, it is significant to scientifically assess the trend of ecological risk changes in Chongqing. The article developed an ecological risk assessment index system for Chongqing, utilizing the \"pressure-state-response\" framework. The entropy weight method (EWM) is employed to assign weights to each variable, subsequently establishing a grey weighted clustering evaluation model (GWCEM). We evaluated the ecological risks of nine central urban areas in Chongqing from 2005 to 2021 and projected the ecological risk levels and changes from 2022 to 2025. Our research indicates that the comprehensive ranking of influencing factors of ecological risk in Chongqing follows this order: response factor > pressure factor > state factor. Throughout the study period, we observed a decrease in the ecological risk values of Ba\'nan, Shapingba, Jiulongpo, Nan\'an and Yubei Districts by more than 50%. These decline rates are accelerating and regional differences in ecological risk levels are diminishing. From 2022 to 2025, except Shapingba, Jiangbei, Yuzhong, and Nan\'an District which consistently maintained a \"low-risk\" level, the ecological risk levels of all other areas continue to decrease, aligning with a \"low-risk\" classification by 2025. Based on the results of ecological risk assessment and ecological risk level prediction, corresponding recommendations are proposed for ecological environment protection and ecological risk management in the central urban area of Chongqing.
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  • 文章类型: Journal Article
    粤港澳大湾区以其非凡的经济发展速度备受关注,被认为是中国从制造业向创新集群转型的领跑者。然而,由于快速的经济扩张和快速的城市化,大湾区仍在能源效率低下和环境恶化中挣扎,这减缓了发展的步伐。因此,为了缓解能源压力,促进国家的可持续发展,在全球市场上获得竞争优势,研究能源效率和提高能源利用效率至关重要。在这项研究中,利用大湾区各城市2000年至2020年的能源消费数据,构建宏观能源效率指标,分析能源效率的时空演变。结果表明,2000年至2019年,大湾区所有城市的能源效率均呈增长趋势,城市之间的增长率和幅度差异显著。与广东省的九个城市相比,香港和澳门表现出显著优越的能源效率,佛山的增长率最高,为14%。2020年,由于COVID-19大流行,大多数城市的能源效率下降,澳门的降幅最大,为57%。香港和澳门都处于"低消耗,高效率"的目标区域,而广州,深圳和珠海一直处于“双高”地区。产业升级指数的变化与能源效率轨迹的变化显著对应,从第一产业向第二产业和第三产业的过渡发挥了更大的作用。环境法规的强度与能源效率的变化之间没有显着关联。研究结果表明,我国大部分地区实现经济转型的最有效途径是将适当的环境立法与产业结构调整相结合。
    The Guangdong-Hong Kong-Macao Greater Bay Area has attracted attention for its extraordinary pace of economic development and is considered to be leading the way in China\'s transformation from a manufacturing to an innovation cluster. However, due to rapid economic expansion and rapid urbanization, the Great Bay Area still struggles with low energy efficiency and environmental degradation, which has slowed down the pace of development. Therefore, in order to alleviate energy pressure, promote the country\'s sustainable development and gain a competitive advantage in the global market, researching energy efficiency and improving energy utilization efficiency is crucial. In this study, macro-level energy efficiency indicators are constructed using energy consumption data from various cities in the Greater Bay Area for the period from 2000 to 2020, and the spatio-temporal evolution of energy efficiency is analysed. The results show that all cities in the Greater Bay Area experienced an increasing trend in energy efficiency from 2000 to 2019, with significant variation in growth rates and magnitudes between cities. Compared to the nine cities in Guangdong province, Hong Kong and Macao exhibited significantly superior energy efficiency, with Foshan recording the highest growth rate of 14%. In 2020, most cities experienced a decline in energy efficiency due to the COVID-19 pandemic, with Macao experiencing the greatest decrease at 57%. Hong Kong and Macao are both in the \"low consumption and high efficiency\" target region, while Guangzhou, Shenzhen and Zhuhai are consistently in the \"both high\" region. Changes in the industrial upgrading index correspond significantly with changes in energy efficiency trajectories, with the transition from primary to secondary and tertiary industries playing a more substantial role. There is no significant association found between the strength of environmental regulation and changes in energy efficiency. The study\'s findings indicate that the most effective way to achieve economic transformation in the majority of China\'s regions is to combine adequate environmental legislation with industrial structural adjustment.
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  • 文章类型: Journal Article
    U-Chang-Shi(乌鲁木齐-昌吉-石河子)城市群,位于新疆的中心,拥有丰富的自然资源。在过去的二十年里,快速城市化,工业化,和气候变化显著威胁到该地区的生态宜居性。为了全面,科学,并客观评估该地区的生态宜居性,本研究利用GoogleEarthEngine(GEE)平台和多源遥感数据来开发综合评价指标:遥感生态宜居指数(RSELI)。本文旨在研究2000年至2020年U长石城市群生态宜居性的变化。调查结果表明,尽管每年都有一些改进,生态宜居的总体趋势正在下降,表明城市化和工业化的快速发展给该地区的生态环境带来了相当大的压力。土地利用变化,在城市扩张和农业和工业用地增长的推动下,逐渐侵占现有的绿地和水体,生态环境进一步恶化。此外,该地区的地形特征影响了其生态宜居性;大的地形波动使水土流失和地质灾害普遍存在。尽管中部平原广阔的河流提供了充足的水资源,过度开发和构思不当的水文建设导致水资源短缺升级。北部靠近古尔班通古特沙漠的地区,生态环境极其脆弱,长期以来一直不适合居住。本研究为乌长石城市群的未来发展提供了至关重要的科学依据,希望为该地区的可持续发展和生态改善提供理论支持和实践指导。
    The U-Chang-Shi (Urumqi-Changji-Shihezi) urban cluster, located at the heart of Xinjiang, boasts abundant natural resources. Over the past two decades, rapid urbanization, industrialization, and climate change have significantly threatened the region\'s ecological livability. To comprehensively, scientifically, and objectively assess the ecological livability of this area, this study leverages the Google Earth Engine (GEE) platform and multi-source remote sensing data to develop a comprehensive evaluation metric: the Remote Sensing Ecological Livability Index (RSELI). This aims to examine the changes in the ecological livability of the U-Chang-Shi urban cluster from 2000 to 2020. The findings show that despite some annual improvements, the overall trend in ecological livability is declining, indicating that the swift pace of urbanization and industrialization has placed considerable pressure on the region\'s ecological environment. Land use changes, driven by urban expansion and the growth in agricultural and industrial lands, have progressively encroached upon existing green spaces and water bodies, further deteriorating the ecological environment. Additionally, the region\'s topographical features have influenced its ecological livability; large terrain fluctuations have made soil erosion and geological disasters common. Despite the central plains\' vast rivers providing ample water resources, over exploitation and ill-conceived hydrological constructions have led to escalating water scarcity. The area near the Gurbantunggut Desert in the north, with its extremely fragile ecological environment, has long been unsuitable for habitation. This study provides a crucial scientific basis for the future development of the U-Chang-Shi urban cluster and hopes to offer theoretical support and practical guidance for the sustainable development and ecological improvement of the region.
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  • 文章类型: Journal Article
    这项研究调查了移民技能的影响,就业部门,城市规划和能源部门对碳排放的效率。利用静态和动态方法动态GMM,2000年至2022年覆盖156个国家的面板数据集上的空间方法。我们的研究结果表明,地缘政治风险的增加导致碳排放和生态足迹的短期和长期增加。结果表明,国际移徙的积极影响,旅游服务和城市化对二氧化碳排放的影响。结果还调查了相互作用的影响,揭示了城市人口密度对国际移民与二氧化碳排放之间关联的放大效应。分类分析表明,移民对高收入国家的二氧化碳排放产生积极影响,低收入,而中上收入经济体存在复杂的关联。这些发现为政策制定者提供了宝贵的见解,以优先采用可再生能源,可持续城市规划,能源效率措施,可持续旅游实践,碳定价机制,国际合作,以及针对特定国家背景量身定制的可持续经济增长战略。
    This study investigates the impact of migrants\' skills, employment sectors, urban planning and energy sectors efficiency on carbon emissions. Utilizing the static and dynamic methods Dynamic GMM, Spatial methods on a panel dataset covering 156 nations from 2000 to 2022. Our findings reveal that heightened geopolitical risk leads to both short and long run increases in carbon emissions and the ecological footprint. The results indicate positive impact of international migration, travel services and urbanization on CO2 emissions. The results also investigate interaction effects, revealing the amplifying effect of urban population density on the association between international migration and CO2 emissions. The disaggregated analysis shows that migrants positively impact CO2 emissions in high income, Lower Income while there is complex association in upper middle-income economies. The findings provide policymakers with valuable insights for prioritizing the adoption of renewable energy, sustainable urban planning, energy efficiency measures, sustainable tourism practices, carbon pricing mechanisms, international cooperation, and sustainable economic growth strategies that are tailored to specific country contexts.
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  • 文章类型: Journal Article
    快速城市化极大地改变了土壤环境,生物多样性,和陆地生态系统的稳定性。土壤微生物群落,全球生物多样性的关键组成部分,在生态系统稳定中起着举足轻重的作用,并且极易受到城市化的影响。然而,城市化对多样性的影响,稳定性,土壤微生物群落的网络结构仍然知之甚少。在这里,研究了土壤微生物群落的多样性和稳定性,包括细菌,真菌,和原生生物,跨越三个城市化水平不同的地区——城市,郊区,和生态区-使用高通量测序技术。我们的结果表明,城市化导致土壤微生物群落的α多样性显着下降,导致土壤稳定性显著下降,通过平均变异度(AVD)评估。稳定性的丧失与土壤真菌和protistan群落的α多样性减少有关,随着细菌之间相互作用的减弱,真菌,和原生生物。值得注意的是,通过网络分析鉴定的大多数梯形物种被归类为细菌(变形杆菌),并与影响AVD的环境因素呈强正相关。这突出表明,细菌的变异性以及真菌和原生生物的不变性对于维持土壤微生物的稳定性至关重要。此外,结构方程模型表明,protistan多样性主要驱动所有研究区域的土壤微生物稳定性。在郊区和生态区,土壤微生物稳定性直接受土壤性质的影响,细菌多样性,和基石物种,以及间接受重金属影响。这些结果强调了城市化如何通过降低多样性和网络复杂性来降低土壤微生物群落的稳定性。而生态区的建立可能有助于保持土壤微生物群落的多样性和稳定性。
    Rapid urbanization considerably alters soil environment, biodiversity, and stability of terrestrial ecosystems. Soil microbial community, a key component of global biodiversity, plays a pivotal role in ecosystem stability and is highly vulnerable to urbanization. However, effects of urbanization on the diversity, stability, and network structure of soil microbial community remain poorly understood. Herein, we investigated the diversity and stability of soil microbial communities, including bacteria, fungi, and protists, across three regions with different levels of urbanization-urban, suburb, and ecoregion-using high-throughput sequencing techniques. Our results revealed that urbanization led to a notable decrease in the alpha diversity of soil microbial community, causing a significant reduction in soil stability, as assessed by the average variation degree (AVD). The loss of stability was linked to the diminished alpha diversity of the soil fungal and protistan communities, along with weakened interactions among bacteria, fungi, and protists. Notably, the majority of keystone species identified through network analysis were classified as bacteria (Proteobacteria) and displayed a strong positive correlation with the environmental factors influencing AVD. This highlights that the variability of bacteria and the immutability of fungi and protists are important to sustain soil microbial stability. Furthermore, structural equation models indicated that protistan diversity primarily drove soil microbial stability across all regions studied. In the suburban and ecoregion areas, soil microbial stability was directly influenced by the soil properties, bacterial diversity, and keystone species, as well as indirectly affected by heavy metals. These results underscore how urbanization can reduce the stability of soil microbial community via declined diversity and network complexity, whereas the establishment of ecoregions maybe contribute to preserve the diversity and stability of soil microbial community.
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  • 文章类型: Journal Article
    城市河流被认为是甲烷(CH4)和二氧化碳(CO2)排放的重要来源。尽管如此,土地利用和城市化对流域尺度城乡河流碳排放的影响尚未得到充分探索。本研究利用中国北方辽河的现场调查研究了CH4和CO2排放的时空变化及其与城市化的关系及其潜在的控制因素。调查结果显示,CH4排放量在秋季达到峰值,而二氧化碳排放量在夏季最高。水气界面处CH4和CO2的平均通量分别为1387.22±2474.98µmol·m-2·d-1和52.78±54.44mmol·m-2·d-1。水质参数占CH4和CO2浓度和通量总变化的80.49%。结构方程模型表明,TN,TP,DTC,电导率对河流CH4和CO2排放有直接影响,标准化直接效应分别为0.50和0.49。营养输入成为主要驱动因素,增加CH4和CO2浓度和通量,特别是在城市附近的河段,可能会收到更高的营养负荷。这项研究强调,土地利用和城市化通过改变养分投入间接影响河流CH4和CO2排放。建议采取有效的土地利用管理和养分投入控制措施,以减少河流CH4和CO2排放。
    Urban rivers are recognized as significant sources of methane (CH4) and carbon dioxide (CO2) emissions. Despite this, the influence of land use and urbanization on carbon emissions across rural-urban rivers at the watershed scale has been insufficiently explored. This study utilized in-situ surveys of the Liao River in northern China to investigate the spatial and temporal variations of CH4 and CO2 emissions and their relationship with urbanization and its potential controlling factors. The findings revealed that CH4 emissions peaked in fall, whereas CO2 emissions were highest in summer. The average fluxes of CH4 and CO2 at the water-gas interface were 1387.22 ± 2474.98 µmol·m-2·d-1 and 52.78 ± 54.44 mmol·m-2·d-1, respectively. Water quality parameters accounted for 80.49 % of the total variation in CH4 and CO2 concentrations and fluxes. Structural equation modeling indicated that TN, TP, DTC, and conductivity had direct effects on riverine CH4 and CO2 emissions, with standardized direct effects of 0.50 and 0.49, respectively. Nutrient input emerged as the primary driver, increasing CH4 and CO2 concentrations and fluxes, particularly in urban-adjacent river sections likely receiving higher nutrient loads. This study underscores that land use and urbanization indirectly influence riverine CH4 and CO2 emissions by modifying nutrient inputs. Effective land use management and nutrient input control are recommended strategies to mitigate riverine CH4 and CO2 emissions.
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