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Abundance, spatial distribution, and physical characteristics of microplastics in stormwater detention

《环境科学与工程前沿(英文)》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1724-y

摘要: Despite extensive research on microplastics (MP) in marine environments, little is known about MP abundance and transport in terrestrial systems. There is, therefore, still little understanding of the main mechanisms driving the substantial transport of MP across different environmental compartments. Storm events can transport MP beyond boundaries, such as from the land to groundwater or the ocean, as has already been discovered for organic carbon transport. Urban stormwater detention ponds are suitable environments to study the impact of stormwater on the environmental fate and transport of MP. Herein, we investigate the longitudinal and vertical distribution of MP within two detention ponds with different physical characteristics. Soil samples were collected at various locations and from multiple depths (surface and subsurface layers) for measuring MP concentrations using fluorescence microscopy. Our findings show that MP are retained more near the inlet of the ponds, and MP of larger sizes were found more abundantly near inlets than outlets. We also found that MP mass and sizes decrease from surface soil to subsurface soil. In the pond, where vegetation (grass root network) was more considerable, MP were found more evenly distributed along the depth. In terms of shape, the fragments were the most abundant MP shape.

关键词: Microplastic     Environmental transport     Soil pollution     Stormwater     Detention ponds    

Spatial distribution of phosphorus forms in sediments with different distances to the estuary of the

Shaoyong LU, Xiangcan JIN, Fengchang WU, Jing SI, Jianning GUO,

《环境科学与工程前沿(英文)》 2010年 第4卷 第3期   页码 295-300 doi: 10.1007/s11783-010-0231-0

摘要: Effects of human activity on the distribution of phosphorus (P) forms were investigated for the sediments and porewaters in Daqinghe Estuary of Dianchi Lake, China. The concentrations of total P (TP), inorganic-P (I-P), and organic-P (Org-P), and the ratio of iron-bound P (Fe-P)/calcium-bound P (Ca-P) in the sediments decreased with the increasing distance from the sampling site to the estuary. This is probably due to the flocculant materials, e.g., ferric and aluminous salts, usually being added in the wastewater treatment processes. The concentration of ammonia in the sediment porewaters significantly decreased with the increasing distance from the sampling site to the estuary. Both concentrations of total nitrogen and nitrogen in the sediment porewaters decreased to some content with the increasing distance from the sampling site to the estuary. However, the concentrations of nitrate, dissolved total P (DTP), and TP did not have strong relationship with the distances from the sampling sites to the estuary. Pollution load and water quantity also had an important influence on the concentrations of P in sediments and its interstitial water in estuary sedimentary area.

关键词: estuary sedimentary area     phosphorus (P)     spatial distribution     human activity     the Dianchi Lake    

Spatial prediction of soil contamination based on machine learning: a review

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1693-1

摘要:

● A review of machine learning (ML) for spatial prediction of soil contamination.

关键词: Soil contamination     Machine learning     Prediction     Spatial distribution    

PyLUR: Efficient software for land use regression modeling the spatial distribution of air pollutants

Xuying Ma, Ian Longley, Jennifer Salmond, Jay Gao

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-020-1221-5

摘要: PyLUR comprises four modules for developing and applying a LUR model. It considers both conventional and novel potential predictor variables. GDAL/OGR libraries are used to do spatial analysis in the modeling and prediction. Developed on Python platform, PyLUR is rather efficient in data processing. Land use regression (LUR) models have been widely used in air pollution modeling. This regression-based approach estimates the ambient pollutant concentrations at un-sampled points of interest by considering the relationship between ambient concentrations and several predictor variables selected from the surrounding environment. Although conceptually quite simple, its successful implementation requires detailed knowledge of the area, expertise in GIS, statistics, and programming skills, which makes this modeling approach relatively inaccessible to novice users. In this contribution, we present a LUR modeling and pollution-mapping software named PyLUR. It uses GDAL/OGR libraries based on the Python platform and can build a LUR model and generate pollutant concentration maps efficiently. This self-developed software comprises four modules: a potential predictor variable generation module, a regression modeling module, a model validation module, and a prediction and mapping module. The performance of the newly developed PyLUR is compared to an existing LUR modeling software called RLUR (with similar functions implemented on R language platform) in terms of model accuracy, processing efficiency and software stability. The results show that PyLUR out-performs RLUR for modeling in the Bradford and Auckland case studies examined. Furthermore, PyLUR is much more efficient in data processing and it has a capability to handle detailed GIS input data.

关键词: LUR     Air pollution modelling     GIS spatial analysis     GDAL/OGR Python     Pollutant concentration mapping    

Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

《工程管理前沿(英文)》 2016年 第3卷 第2期   页码 171-181 doi: 10.15302/J-FEM-2016017

摘要: Utilizing the initial hourly monitoring data of PM concentrations at 23 monitoring sites across the Chang-Zhu-Tan city cluster between January 2013 and February 2014 that released in Real-time Air Quality Reporting System in Hunan Province, this paper draws diagrams and analyzes the change rule of the pollutants concentration over time. In addition, this paper studies the regional distribution of PM seasonal pollution in the vicinity of the monitoring sites using ArcGIS geographic information system with the Kriging interpolation method. On this basis, this paper puts forward some effective control strategies to cope with regional PM pollution combined with the information of industry distribution and development status in the Chang-Zhu-Tan city cluster.

关键词: PM2.5     spatial and temporal distribution     ArcGIS     the chang-Zhu-Tan city cluster    

Digital representation of meso-geomaterial spatial distribution and associated numerical analysis of

YUE Zhongqi

《结构与土木工程前沿(英文)》 2007年 第1卷 第1期   页码 80-93 doi: 10.1007/s11709-007-0008-0

摘要: This paper presents the author's efforts in the past decade for the establishment of a practical approach of digital representation of the geomaterial distribution of different minerals, particulars, and components in the meso-scale range (0.1 to 500 mm). The primary goal of the approach is to provide a possible solution to solve the two intrinsic problems associated with the current main-stream methods for geomechanics. The problems are (1) the constitutive models and parameters of soils and rocks cannot be given accurately in geomechanical prediction; and (2) there are numerous constitutive models of soils and rocks in the literature. The problems are possibly caused by the homogenization or averaging method in analyzing laboratory test results for establishing the constitutive models and parameters. The averaging method employs an assumption that the test samples can be represented by a homogeneous medium. Such averaging method ignores the fact that the geomaterial samples are also consisted of a number of materials and components whose properties may have significant differences. In the proposed approach, digital image processing methods are used as measurement tools to construct a digital representation for the actual spatial distribution of the different materials and components in geomaterial samples. The digital data are further processed to automatically generate meshes or grids for numerical analysis. These meshes or grids can be easily incorporated into existing numerical software packages for further mechanical analysis and failure prediction of the geomaterials under external loading. The paper presents case studies to illustrate the proposed approach. Further discussions are also made on how to use the proposed approach to develop the geomechanics by taking into account the geomaterial behavior at micro-scale, meso-scale and macro-scale levels. A literature review of the related developments is given by examining the SCI papers in the database of Science Citation Index Expanded. The results of this review have shown that the proposed approach is one of the latest research and developments in geomechanics where actual spatial distribution and properties of materials and components at the meso-level are taken into account.

关键词: homogeneous     numerical analysis     Expanded     homogenization     meso-level    

Multimedia distribution and health risk assessment of typical organic pollutants in a retired industrial

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1742-9

摘要:

● A fine portrayal of organic pollutants in a retired industrial park is provided.

关键词: Organic pollutants     Retired industrial park     Spatial correlation     Health risk assessment    

Spatial distribution of ecological security status assessment of West-Liaohe River based on geographic

WANG Geng, WU Wei

《环境科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 471-476 doi: 10.1007/s11783-007-0075-4

摘要: Eco-security assessment is a hot research area in resource and environmental science, which involves data with much spatial, non-linear, and random features. Geographic information system (GIS), as a useful tool to analyze and mana

关键词: environmental     Eco-security assessment     resource     Geographic information     non-linear    

黄淮海平原浅层地下水中NO3-N含量的空间变异与分布特征

李保国,白由路,胡克林,黄元仿,陈德立

《中国工程科学》 2001年 第3卷 第4期   页码 42-45

摘要:

通过GPS定位取样分析和GIS处理,研究了黄淮海平原浅层地下水中NO3-N含量的空间变异和分布特征。结果表明,黄淮海平原浅层地下水中NO3-N含量在35~50km的取样密度下,没有半方差结构,各取样点之间变异性较大;黄淮海平原有10%的面积浅层地下水中NO3-N含量超过20 mg·L-1,主要分布在天津至济南一线和淮河流域的新蔡、阜阳和蚌埠一带。徐州至连云港一带的苏北地区及山东的潍坊地区,浅层地下水中的NO3-N含量一般在10~20 mg·L-1之间,约占黄淮海平原总面积的11.5%。浅层地下水中NO3-N 的含量与地下水埋深密切相关,NO3-N含量超过20 mg·L-1的地下水埋深一般在3 m以上,地下水埋深在10 m以下时,其中的NO3-N含量均不超过10mg·L-1。这表明,目前通过土壤NO3-N的淋失对该区地下水中 NO3-N含量影响深度一般不超过10 m。此项研究结果对于黄淮海平原持续发展,制定优化的高效水肥管理措 施和方案有一定指导意义。

关键词: 黄淮海平原     地下水     NO3-N     空间分布    

基于惯性能时空最优分布的高加速轻载机构精密定位方法 Article

陈新,白有盾,杨志军,高健,陈贡发

《工程(英文)》 2015年 第1卷 第3期   页码 391-398 doi: 10.15302/J-ENG-2015063

摘要:

高速运动精密定位是微电子封装设备中高加速轻载执行机构的基本运动需求。本文推导了高加速机构瞬态非线性动力学响应方程,揭示了刚度、频率、阻尼 (与材料空间布局相关) 和驱动频率 (与运动规划相关) 是主要影响因素。据此,在满足高加速机构精密定位的条件下,笔者提出了一种基于最优非线性动力学响应的结构优化和速度规划新方法。在结构优化中,首先分析了目前流行的基于等效静态载荷的柔性多体动力学优化方法未充分考虑惯性载荷的不足,然后提出了基于等效模态的柔性多体动力学最优动态响应优化新方法;在速度规划上,针对传统的几何光滑方法不能反映系统动态特性的缺陷,提出了基于变边界条件非线性动力学响应优化的速度规划新方法。将所提方法应用到高速固晶焊头的优化设计中,通过结构优化,降低振幅超过20%,再经非对称变加速规划,缩短定位时间超过40%。本文提出的方法为微电子封装类装备等高加速轻载机构精密定位的实现提供了有效的理论支撑和解决途径。

关键词: 高加速轻载机构     精密定位     时空分布     惯性能     等效静态载荷方法     速度规划    

中国能源资源基地分布与管理政策研究

吴尚昆,张玉韩

《中国工程科学》 2019年 第21卷 第1期   页码 81-87 doi: 10.15302/J-SSCAE-2019.01.012

摘要:

能源资源基地是我国矿产资源安全保障的战略核心区域,肩负着保障国家资源安全的重要使命,对优化矿产资源空间开发格局、转变矿业发展方式、推动矿业高质量发展具有重要意义。本文以《全国矿产资源规划(2016—2020年)》中提出的103个能源资源基地为研究对象,对基地的内涵和定位、基本理论支撑、建设任务以及划定原则等进行了探讨,从矿种和地域两方面分析了能源资源基地的分布态势,提出基地划定与管理中存在的问题,包括管理上没有纳入省级发展规划,建设规划编制不到位,与国家规划矿区不匹配和激励政策不具体等。从落实方案、监管政策、激励政策、机制建设、保障体系等五个方面提出了推动能源资源基地建设的政策建议,以期为矿产资源战略规划管理提供支撑。
 

关键词: 能源资源基地     矿产资源战略规划     空间分布     管理政策    

A building-based data capture and data mining technique for air quality assessment

Ni SHENG, U Wa TANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第4期   页码 543-551 doi: 10.1007/s11783-011-0369-4

摘要: Recently, a building-based air quality model system which can predict air quality in front of individual buildings along both sides of a road has been developed. Using the Macau Peninsula as a case study, this paper shows the advantages of building-based model system in data capture and data mining. Compared with the traditional grid-based model systems with input/output spatial resolutions of 1–2 km, the building-based approach can extract the street configuration and traffic data building by building and therefore, can capture the complex spatial variation of traffic emission, urban geometry, and air pollution. The non-homogeneous distribution of air pollution in the Macau Peninsula was modeled in a high-spatial resolution of 319 receptors·km . The spatial relationship among air quality, traffic flow, and urban geometry in the historic urban area is investigated. The study shows that the building-based approach may open an innovative methodology in data mining of urban spatial data for environmental assessment. The results are particularly useful to urban planners when they need to consider the influences of urban form on street environment.

关键词: traffic air pollution     spatial distribution     high resolution     geographic information system    

Changes in hourly precipitation may explain the sharp reduction of discharge in the middle reach of the Yellow River after 2000

Lin LUO, Zhongjing WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第5期   页码 756-768 doi: 10.1007/s11783-013-0563-7

摘要: The Hekou-Longmen reach, together with local floods, is the main source area for coarse sedimentations into the Yellow River. When total rainfall slightly increased in the area, discharge dramatically decreased by 40%–70% after the year of 2000, and attracting extensive attention in the context of global climate change. High temporal resolution precipitation (timescales between 1 and 4 h) data from the June to September period from 270 rain gauges over the past three decades was mined in order to help explain the phenomenon. Each rainfall event was classified as light/moderate rain, large rain, heavy rain or rainstorm by the event’s rainfall amount, and further classified as low intensity rain, medium intensity rain and high intensity rain by the event’s rainfall intensity. The Mann-Kendall trend test was applied to detect the presence and significance of monotonic trends, and to find the change points in the mean and variance of the precipitation characteristics series, including the amount, intensity, frequency and duration of each rainfall category. Results show that although the total amount of precipitation has slightly increased, the average rainfall intensity has significantly decreased. The larger change happened in light/moderate rain events and low/medium intensity rain events, and the intensity changes have a great extent occurred around the threshold of Non-Runoff Rainfall regime, which was proposed for the approximate calculation of initial losses. Changes in rainfall distribution between different classes of the Runoff Rainfall regime in the 2000s could lead to 0.9 mm less runoff depth (17.3% of the total reduction) than the 1980–1999 period. The study indicates that changes in hourly precipitation may be responsible for the sharp reduction of discharge.

关键词: precipitation intensity     Mann-Kendall rank statistic     spatial and temporal distribution     climatic change    

Distribution of aromatic amines, phenols, chlorobenzenes, and naphthalenes in the surface sediment of

Xinyi Hu, Ting Yang, Chen Liu, Jun Jin, Bingli Gao, Xuejun Wang, Min Qi, Baokai Wei, Yuyu Zhan, Tan Chen, Hongtao Wang, Yanting Liu, Dongrui Bai, Zhu Rao, Nan Zhan

《环境科学与工程前沿(英文)》 2020年 第14卷 第4期 doi: 10.1007/s11783-020-1245-x

摘要: Abstract • The total organic pollutant concentrations in sediment were 27.4-1620 ng/g. • The phenol concentrations were relatively high in the sediment of the Dianchi Lake. • Average total concentrations decreased as follows: Caohai>Waihai>Haigeng Dam. • 1,4-dichlorobenzene, 3- or 4-methylphenol, 1,2,4-trichlorobenzene might be risks. Organic pollutants are widespread environmental pollutants with high toxicity, persistence, and bioaccumulation. Our aim was to investigate the distribution of aromatic amines, phenols, chlorobenzenes, and naphthalenes in the surface sediment of the Dianchi Lake, China. Nineteen surface sediment samples were collected from the Dianchi Lake, and 40 types of organic pollutants were analyzed via gas chromatography–mass spectrometry. The total organic pollutant concentrations in the surface sediment of the Dianchi Lake varied from 27.4 to 1.62 × 103 ng/g. The concentrations of phenols were much higher than those in other water bodies but still within a controllable range, whereas the concentrations of the other organic pollutant classes were similar or even lower. The detection ratio of 3- or 4-methylphenol was the highest (100.00%) among the pollutants. The average total organic pollutant concentrations decreased in the following order: Caohai (540 ng/g)>the middle of Waihai (488 ng/g)>the edge of Waihai (351 ng/g)>Haigeng Dam (90.4 ng/g). Pearson analysis showed a strong correlation among 1-methylnaphthalene, 2-methylnaphthalene, 1,3-dinitronaphthalene, and 1,4-dinitronaphthalene (p<0.01). Caohai, the north lakeshore of Waihai and the south of Waihai showed higher risk because of high concentration; meanwhile, 1,4-dichlorobenzene, 3- or 4-methylphenol and 1,2,4-trichlorobenzene were more likely to cause risks.

关键词: Organic pollutants     Lake sediment     Spatial distribution     Potential source    

Soil spatial variability impact on the behavior of a reinforced earth wall

Adam HAMROUNI, Daniel DIAS, Badreddine SBARTAI

《结构与土木工程前沿(英文)》 2020年 第14卷 第2期   页码 518-531 doi: 10.1007/s11709-020-0611-x

摘要: This article presents the soil spatial variability effect on the performance of a reinforced earth wall. The serviceability limit state is considered in the analysis. Both cases of isotropic and anisotropic non-normal random fields are implemented for the soil properties. The Karhunen-Loève expansion method is used for the discretization of the random field. Numerical finite difference models are considered as deterministic models. The Monte Carlo simulation technique is used to obtain the deformation response variability of the reinforced soil retaining wall. The influences of the spatial variability response of the geotechnical system in terms of horizontal facing displacement is presented and discussed. The results obtained show that the spatial variability has an important influence on the facing horizontal displacement as well as on the failure probability.

关键词: reinforced earth wall     geosynthetic     random field     spatial variability     Monte Carlo simulation    

标题 作者 时间 类型 操作

Abundance, spatial distribution, and physical characteristics of microplastics in stormwater detention

期刊论文

Spatial distribution of phosphorus forms in sediments with different distances to the estuary of the

Shaoyong LU, Xiangcan JIN, Fengchang WU, Jing SI, Jianning GUO,

期刊论文

Spatial prediction of soil contamination based on machine learning: a review

期刊论文

PyLUR: Efficient software for land use regression modeling the spatial distribution of air pollutants

Xuying Ma, Ian Longley, Jennifer Salmond, Jay Gao

期刊论文

Spatial and Temporal Distribution of PM

Xiao-hong Chen,Xiang-bo Tang

期刊论文

Digital representation of meso-geomaterial spatial distribution and associated numerical analysis of

YUE Zhongqi

期刊论文

Multimedia distribution and health risk assessment of typical organic pollutants in a retired industrial

期刊论文

Spatial distribution of ecological security status assessment of West-Liaohe River based on geographic

WANG Geng, WU Wei

期刊论文

黄淮海平原浅层地下水中NO3-N含量的空间变异与分布特征

李保国,白由路,胡克林,黄元仿,陈德立

期刊论文

基于惯性能时空最优分布的高加速轻载机构精密定位方法

陈新,白有盾,杨志军,高健,陈贡发

期刊论文

中国能源资源基地分布与管理政策研究

吴尚昆,张玉韩

期刊论文

A building-based data capture and data mining technique for air quality assessment

Ni SHENG, U Wa TANG

期刊论文

Changes in hourly precipitation may explain the sharp reduction of discharge in the middle reach of the Yellow River after 2000

Lin LUO, Zhongjing WANG

期刊论文

Distribution of aromatic amines, phenols, chlorobenzenes, and naphthalenes in the surface sediment of

Xinyi Hu, Ting Yang, Chen Liu, Jun Jin, Bingli Gao, Xuejun Wang, Min Qi, Baokai Wei, Yuyu Zhan, Tan Chen, Hongtao Wang, Yanting Liu, Dongrui Bai, Zhu Rao, Nan Zhan

期刊论文

Soil spatial variability impact on the behavior of a reinforced earth wall

Adam HAMROUNI, Daniel DIAS, Badreddine SBARTAI

期刊论文