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Non-Point Source Pollution and Environmental Assessment

A special issue of International Journal of Environmental Research and Public Health (ISSN 1660-4601). This special issue belongs to the section "Environmental Science and Engineering".

Deadline for manuscript submissions: closed (30 September 2018) | Viewed by 58575

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Department of Civil and Environmental Engineering, North Dakota State University, Fargo, ND 58105, USA
Interests: watershed modelling; environmental modelling; vadose zone hydrology; hydrotopographic analysis; groundwater modelling
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Special Issue Information

Dear Colleagues,

Non-point source (NPS) pollution involves a variety of pollutants, such as nutrients, pesticides, heavy metals, bacteria/pathogens, and sediments from various diffuse sources. With surface runoff, these pollutants eventually transport into rivers, lakes, wetlands, and aquifers, resulting in contamination of both surface and subsurface systems. Improved understanding of their sources and pathways throughout surface and subsurface environments, effective monitoring and modeling methodologies, and strategic environmental assessment are critical to sustainable ecosystems and society.

This Special Issue of IJERPH focuses on all aspects related to NPS pollution, monitoring, modeling, and assessment. The topics include, but are not limited to: occurrence and distribution of NPS pollutants in surface water and groundwater, modeling of the fate and transport of NPS pollutants in surface and subsurface environments, watershed water quality modeling (e.g., SWAT modeling), NPS water quality management and environmental assessment (e.g., development of TMDLs and BMPs). It is open to both theoretical and applied studies. NPS pollution is a global issue. Thus, the NPS-related studies from different countries and regions are particularly encouraged.

Dr. Xuefeng Chu
Guest Editor

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Keywords

  • NPS pollution
  • NPS management
  • environmental assessment
  • transport modeling
  • nutrients
  • pesticides
  • heavy metals
  • bacteria/pathogens
  • sediments
  • watershed modeling

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Published Papers (13 papers)

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Research

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17 pages, 3440 KiB  
Article
SWAT Modeling of Non-Point Source Pollution in Depression-Dominated Basins under Varying Hydroclimatic Conditions
by Mohsen Tahmasebi Nasab, Kendall Grimm, Mohammad Hadi Bazrkar, Lan Zeng, Afshin Shabani, Xiaodong Zhang and Xuefeng Chu
Int. J. Environ. Res. Public Health 2018, 15(11), 2492; https://doi.org/10.3390/ijerph15112492 - 8 Nov 2018
Cited by 30 | Viewed by 4383
Abstract
Non-point source (NPS) pollution from agricultural lands is the leading cause of various water quality problems across the United States. Particularly, surface depressions often alter the releasing patterns of NPS pollutants into the environment. However, most commonly-used hydrologic models may not be applicable [...] Read more.
Non-point source (NPS) pollution from agricultural lands is the leading cause of various water quality problems across the United States. Particularly, surface depressions often alter the releasing patterns of NPS pollutants into the environment. However, most commonly-used hydrologic models may not be applicable to such depression-dominated regions. The objective of this study is to improve water quantity/quality modeling and its calibration for depression-dominated basins under wet and dry hydroclimatic conditions. Specifically, the Soil and Water Assessment Tool (SWAT) was applied for hydrologic and water quality modeling in the Red River of the North Basin (RRB). Surface depressions across the RRB were incorporated into the model by employing a surface delineation method and the impacts of depressions were evaluated for two modeling scenarios, MS1 (basic scenario) and MS2 (depression-oriented scenario). Moreover, a traditional calibration scheme (CS1) was compared to a wet-dry calibration scheme (CS2) that accounted for the effects of hydroclimatic variations on hydrologic and water quality modeling. Results indicated that the surface runoff simulation and the associated water quality modeling were improved when topographic characteristics of depressions were incorporated into the model (MS2). The Nash–Sutcliffe efficiency (NSE) coefficient indicated an average increase of 30.4% and 19.6% from CS1 to CS2 for the calibration and validation periods, respectively. Additionally, the CS2 provided acceptable simulations of water quality, with the NSE values of 0.50 and 0.74 for calibration and validation periods, respectively. These results highlight the enhanced capability of the proposed approach for simulating water quantity and quality for depression-dominated basins under the influence of varying hydroclimatic conditions. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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11 pages, 1047 KiB  
Article
Concentrations, Distributions, and Risk Assessment of HBCD in Sediment in the Weihe River Basin in Northwest China
by Xueli Wang, Xiaoyu Yuan, Shengke Yang and Yaqian Zhao
Int. J. Environ. Res. Public Health 2018, 15(11), 2340; https://doi.org/10.3390/ijerph15112340 - 23 Oct 2018
Cited by 12 | Viewed by 4048
Abstract
As one of the most widely used brominated flame retardants, hexabromocyclododecane (HBCD) is found widely in the environmental media. In this study, the content and spatial distribution of HBCD and risk posed by HBCD in surface sediment in the Weihe River Basin in [...] Read more.
As one of the most widely used brominated flame retardants, hexabromocyclododecane (HBCD) is found widely in the environmental media. In this study, the content and spatial distribution of HBCD and risk posed by HBCD in surface sediment in the Weihe River Basin in Northwest China were investigated. The HBCD concentration ranged nd–4.04 ng/g dw with the mean was 0.45 ng/g dw. The major source of HBCD in surface sediment was local point discharge. The distribution profiles of α-, β-, γ-HBCD were 24.7–87.9%, 0–42.0%, and 0–67.1%, respectively. Specially, α-HBCD was the dominating isomer in most sample sites. This differed significantly from that in HBCD technical product, which might be attributed to the different degradation rates and inter-transformation of the three HBCD isomers. Risk quotient method was used to assess the potential risk posed by HBCD in sediment. HBCD do not pose strong risks to aquatic algae organisms in the Weihe River Basin. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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12 pages, 4031 KiB  
Article
Assessment of Long-Term Watershed Management on Reservoir Phosphorus Concentrations and Export Fluxes
by Xiaolin Huang, Han Chen, Fang Xia, Zhenfeng Wang, Kun Mei, Xu Shang, Yuanyuan Liu, Randy A. Dahlgren, Minghua Zhang and Hong Huang
Int. J. Environ. Res. Public Health 2018, 15(10), 2169; https://doi.org/10.3390/ijerph15102169 - 2 Oct 2018
Cited by 5 | Viewed by 2853
Abstract
Source water nutrient management to prevent eutrophication requires critical strategies to reduce watershed phosphorus (P) loadings. Shanxi Drinking-Water Source Area (SDWSA) in eastern China experienced severe water quality deterioration before 2010, but showed considerable improvement following application of several watershed management actions to [...] Read more.
Source water nutrient management to prevent eutrophication requires critical strategies to reduce watershed phosphorus (P) loadings. Shanxi Drinking-Water Source Area (SDWSA) in eastern China experienced severe water quality deterioration before 2010, but showed considerable improvement following application of several watershed management actions to reduce P. This paper assessed the changes in total phosphorus (TP) concentrations and fluxes at the SDWSA outlet relative to watershed anthropogenic P sources during 2005–2016. Overall anthropogenic P inputs decreased by 21.5% over the study period. Domestic sewage, livestock, and fertilizer accounted for (mean ± SD) 18.4 ± 0.6%, 30.1 ± 1.9%, and 51.5 ± 1.5% of total anthropogenic P inputs during 2005–2010, compared to 24.3 ± 2.7%, 8.8 ± 10.7%, and 66.9 ± 8.0% for the 2011–2016 period, respectively. Annual average TP concentrations in SDWSA decreased from 0.041 ± 0.019 mg/L in 2009 to 0.025 ± 0.013 mg/L in 2016, a total decrease of 38.2%. Annual P flux exported from SDWSA decreased from 0.46 ± 0.04 kg P/(ha·a) in 2010 to 0.25 ± 0.02 kg P/(ha·a) in 2016, a decrease of 44.9%. The success in reducing TP concentrations was mainly due to the development of domestic sewage/refuse collection/treatment and improved livestock management. These P management practices have prevented harmful algal blooms, providing for safe drinking water. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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23 pages, 8331 KiB  
Article
Effectiveness of Best Management Practices to Reduce Phosphorus Loading to a Highly Eutrophic Lake
by Alan D. Steinman, Michael Hassett and Maggie Oudsema
Int. J. Environ. Res. Public Health 2018, 15(10), 2111; https://doi.org/10.3390/ijerph15102111 - 25 Sep 2018
Cited by 10 | Viewed by 3782
Abstract
Reducing nonpoint source pollution is an ongoing challenge in watersheds throughout the world. Implementation of best management practices, both structural and nonstructural, is the usual response to this challenge, with the presumption that they are effective. However, monitoring of their efficacy is not [...] Read more.
Reducing nonpoint source pollution is an ongoing challenge in watersheds throughout the world. Implementation of best management practices, both structural and nonstructural, is the usual response to this challenge, with the presumption that they are effective. However, monitoring of their efficacy is not a standard practice. In this study, we evaluate the effectiveness of two wetland restoration projects, designed to handle runoff during high flow events and serve as flow-through retention basins before returning flow further downstream. The Macatawa Watershed is located in west Michigan, is heavily agricultural, and drains into Lake Macatawa, a hypereutrophic lake with total phosphorus concentrations usually exceeding 100 µg/L. We measured turbidity, total phosphorus, and soluble reactive phosphorus both upstream and downstream of these wetland complexes during base flow and storm events. While both turbidity and phosphorus increased significantly during storm events compared to baseflow, we found no significant difference in upstream vs. downstream water quality two years following BMP construction. We also measured water quality in Lake Macatawa, and found the lake remained highly impaired. Possible reasons for the lack of improved water quality: (1) The restored wetlands are too young to function optimally in sediment and phosphorus retention; (2) the scale of these BMPs is too small given the overall loads; (3) the locations of these BMPs are not optimal in terms of pollutant reduction; and (4) the years following postconstruction were relatively dry so the wetlands had limited opportunity to retain pollutants. These possibilities are evaluated. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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29 pages, 17183 KiB  
Article
The Impacts of Land Use Patterns on Water Quality in a Trans-Boundary River Basin in Northeast China Based on Eco-Functional Regionalization
by Peixuan Cheng, Fansheng Meng, Yeyao Wang, Lingsong Zhang, Qi Yang and Mingcen Jiang
Int. J. Environ. Res. Public Health 2018, 15(9), 1872; https://doi.org/10.3390/ijerph15091872 - 29 Aug 2018
Cited by 34 | Viewed by 3715
Abstract
The relationships between land use patterns and water quality in trans-boundary watersheds remain elusive due to the heterogeneous natural environment. We assess the impact of land use patterns on water quality at different eco-functional regions in the Songhua River basin during two hydrological [...] Read more.
The relationships between land use patterns and water quality in trans-boundary watersheds remain elusive due to the heterogeneous natural environment. We assess the impact of land use patterns on water quality at different eco-functional regions in the Songhua River basin during two hydrological seasons in 2016. The partial least square regression indicated that agricultural activities associated with most water quality pollutants in the region with a relative higher runoff depth and lower altitude. Intensive grazing had negative impacts on water quality in plain areas with low runoff depth. Forest was related negatively with degraded water quality in mountainous high flow region. Patch density and edge density had major impacts on water quality contaminants especially in mountainous high flow region; Contagion was related with non-point source pollutants in mountainous normal flow region; landscape shape index was an effective indicator for anions in some eco-regions in high flow season; Shannon’s diversity index contributed to degraded water quality in each eco-region, indicating the variation of landscape heterogeneity influenced water quality regardless of natural environment. The results provide a regional based approach of identifying the impact of land use patterns on water quality in order to improve water pollution control and land use management. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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14 pages, 1166 KiB  
Article
Correlation Analysis between Landscape Metrics and Water Quality under Multiple Scales
by Xin Zhang, Yuqi Liu and Lin Zhou
Int. J. Environ. Res. Public Health 2018, 15(8), 1606; https://doi.org/10.3390/ijerph15081606 - 28 Jul 2018
Cited by 30 | Viewed by 4191
Abstract
Non-point source pollution is the main factor causing water quality deterioration. Landscape patterns affect the transmission of non-point source pollutants. Many studies have been carried out to analyze the correlation between landscape patterns and water quality, while most former studies neglected the scale [...] Read more.
Non-point source pollution is the main factor causing water quality deterioration. Landscape patterns affect the transmission of non-point source pollutants. Many studies have been carried out to analyze the correlation between landscape patterns and water quality, while most former studies neglected the scale effect. The Jiulong River basin in southeast China was selected as the study area. Based on a landscape cover map generated from satellite images, we determined the riparian buffer zones with different widths, set the catchment as the complementary scale, and then established the multiple linear regression models to explore the relationship between landscape metrics and water quality indices at different scales. The degree of significance of the effect of various landscape metrics on the water quality at different scales was quantitatively analyzed in this paper by using multiple linear regression analysis. The results showed that not only the impact of landscape metrics but also the influence of land cover type on the water quality indices would vary when the spatial scale changed. The credible regression models established in this study can help regional managers understand the correlation between landscape and water quality, and the regression results can be used for land use allocation in a watershed. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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15 pages, 3270 KiB  
Article
Modeling Land Use Changes and their Impacts on Non-Point Source Pollution in a Southeast China Coastal Watershed
by Xin Zhang, Lin Zhou and Yuqi Liu
Int. J. Environ. Res. Public Health 2018, 15(8), 1593; https://doi.org/10.3390/ijerph15081593 - 27 Jul 2018
Cited by 27 | Viewed by 3766
Abstract
Changes in landscape patterns in a river basin play a crucial role in the change on load of non-point source pollution. The spatial distribution of various land use types affects the transmission of non-point source pollutants on the basis of source-sink theory in [...] Read more.
Changes in landscape patterns in a river basin play a crucial role in the change on load of non-point source pollution. The spatial distribution of various land use types affects the transmission of non-point source pollutants on the basis of source-sink theory in landscape ecology. Jiulong River basin in southeast of China was selected as the study area in this paper. Aiming to analyze the correlation between changing landscape patterns and load of non-point source pollution in this area, traditional landscape metrics and the improved location-weighted landscape contrast index based on the minimum hydrological response unit (HRULCI) were applied in this study, in combination with remote sensing and geographic information system (GIS) technique. The results of the landscape metrics showed the enhanced fragmentation extent and the decreasing polymerization degree of the overall landscape in the watershed. High values of HRULCI were concentrated in cultivated land, while low HRULCI values mostly appeared in forestland, indicating that cultivated land substantially enhanced non-point source pollution, while forestland inhibited the pollution process. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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15 pages, 5531 KiB  
Article
Role of Sediments in Insecticide Runoff from Urban Surfaces: Analysis and Modeling
by Angela Gorgoglione, Fabián A. Bombardelli, Bruno J. L. Pitton, Lorence R. Oki, Darren L. Haver and Thomas M. Young
Int. J. Environ. Res. Public Health 2018, 15(7), 1464; https://doi.org/10.3390/ijerph15071464 - 11 Jul 2018
Cited by 26 | Viewed by 5391
Abstract
Insecticides, such as pyrethroids, have frequently been detected in runoff from urban areas, and their offsite transport can cause aquatic toxicity in urban streams and estuaries. To better understand the wash-off process of pesticide residues in urban runoff, the association of pyrethroids with [...] Read more.
Insecticides, such as pyrethroids, have frequently been detected in runoff from urban areas, and their offsite transport can cause aquatic toxicity in urban streams and estuaries. To better understand the wash-off process of pesticide residues in urban runoff, the association of pyrethroids with sediment in runoff from residential surfaces was investigated in two watersheds located in Northern California (Sacramento County). Rainfall, flow rate, and event mean concentrations/loads of sediments and pyrethroids, collected during seasonal monitoring campaigns from 2007 to 2014, were analyzed to identify relationships among stormwater quality and rainfall characteristics, primarily using Principal Component Analysis (PCA). Pyrethroid wash-off was strongly related to sediment wash-off whenever sediment loads exceeded 10 mg; this value was conveniently selected as a threshold between dissolved and particle-bound control of off-site pyrethroid transport. A new mechanistic model for predicting pyrethroid wash-off profiles from residential surfaces at basin-scale was implemented in the Storm Water Management Model (SWMM). The accuracy of the model predictions was estimated by evaluating the root mean square error (RMSE), Nash–Sutcliff efficiency (NSE), and Kling–Gupta efficiency (KGE) for each pyrethroid detected (RMSEtot = 0.13; NSEtot = 0.28; KGEtot = 0.56). The importance of particle-bound transport revealed in this work confirms previous field investigations at a smaller scale, and it should be a key consideration when developing policies to mitigate pesticide runoff from urban areas. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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19 pages, 7173 KiB  
Article
Assessment of Groundwater Susceptibility to Non-Point Source Contaminants Using Three-Dimensional Transient Indexes
by Yong Zhang, Gary S. Weissmann, Graham E. Fogg, Bingqing Lu, HongGuang Sun and Chunmiao Zheng
Int. J. Environ. Res. Public Health 2018, 15(6), 1177; https://doi.org/10.3390/ijerph15061177 - 5 Jun 2018
Cited by 15 | Viewed by 4770
Abstract
Groundwater susceptibility to non-point source contamination is typically quantified by stable indexes, while groundwater quality evolution (or deterioration globally) can be a long-term process that may last for decades and exhibit strong temporal variations. This study proposes a three-dimensional (3-d), transient [...] Read more.
Groundwater susceptibility to non-point source contamination is typically quantified by stable indexes, while groundwater quality evolution (or deterioration globally) can be a long-term process that may last for decades and exhibit strong temporal variations. This study proposes a three-dimensional (3-d), transient index map built upon physical models to characterize the complete temporal evolution of deep aquifer susceptibility. For illustration purposes, the previous travel time probability density (BTTPD) approach is extended to assess the 3-d deep groundwater susceptibility to non-point source contamination within a sequence stratigraphic framework observed in the Kings River fluvial fan (KRFF) aquifer. The BTTPD, which represents complete age distributions underlying a single groundwater sample in a regional-scale aquifer, is used as a quantitative, transient measure of aquifer susceptibility. The resultant 3-d imaging of susceptibility using the simulated BTTPDs in KRFF reveals the strong influence of regional-scale heterogeneity on susceptibility. The regional-scale incised-valley fill deposits increase the susceptibility of aquifers by enhancing rapid downward solute movement and displaying relatively narrow and young age distributions. In contrast, the regional-scale sequence-boundary paleosols within the open-fan deposits “protect” deep aquifers by slowing downward solute movement and displaying a relatively broad and old age distribution. Further comparison of the simulated susceptibility index maps to known contaminant distributions shows that these maps are generally consistent with the high concentration and quick evolution of 1,2-dibromo-3-chloropropane (DBCP) in groundwater around the incised-valley fill since the 1970s’. This application demonstrates that the BTTPDs can be used as quantitative and transient measures of deep aquifer susceptibility to non-point source contamination. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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10 pages, 1560 KiB  
Article
Enhanced Nutrients Removal Using Reeds Straw as Carbon Source in a Laboratory Scale Constructed Wetland
by Tong Wang, Haiyan Wang, Yang Chang, Zhaosheng Chu, Yaqian Zhao and Ranbin Liu
Int. J. Environ. Res. Public Health 2018, 15(6), 1081; https://doi.org/10.3390/ijerph15061081 - 27 May 2018
Cited by 14 | Viewed by 4310
Abstract
The low carbon/nitrogen (C/N) ratio and high nitrate content characteristics of agricultural runoff restricted the nitrogen removal in constructed wetlands (CWs). To resolve such problems, the economically- and easily-obtained Phragmites Australis (reeds) litters were applied and packed in the surface layer of a [...] Read more.
The low carbon/nitrogen (C/N) ratio and high nitrate content characteristics of agricultural runoff restricted the nitrogen removal in constructed wetlands (CWs). To resolve such problems, the economically- and easily-obtained Phragmites Australis (reeds) litters were applied and packed in the surface layer of a surface flow CW as external carbon sources. The results demonstrated that the introduction of the reeds straw increased the C concentration as a result of their decomposition during the CW operation, which will help the denitrification in the ensuing operation of an entire 148 days. The total nitrogen (TN) and Chemical Oxygen Demand (COD) () in the effluent reached the peak level of 63.2 mg/L and 83 mg/L at the fourth and the second day, respectively. Subsequently, the pollutants in the CW that were filled with straw decreased rapidly and achieved a stable removal after 13 days of operation. Moreover, the present study showed that the N removal efficiency increased with the increase of the hydraulic retention time (HRT). Under the HRT of four days, the CW presented 74.1 ± 6%, 87.4 ± 6% and 56.0 ± 6% removal for TN, NO3-, and TP, respectively. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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16 pages, 6392 KiB  
Article
Identifying the Driving Factors of Water Quality in a Sub-Watershed of the Republican River Basin, Kansas USA
by Morgen W. V. Burke, Mojtaba Shahabi, Yeqian Xu, Haochi Zheng, Xiaodong Zhang and Jeffrey VanLooy
Int. J. Environ. Res. Public Health 2018, 15(5), 1041; https://doi.org/10.3390/ijerph15051041 - 22 May 2018
Cited by 8 | Viewed by 4107
Abstract
Studies have shown that the agricultural expansion and land use changes in the Midwest of the U.S. are major drivers for increased nonpoint source pollution throughout the regional river systems. In this study, we empirically examined the relationship of planted area and production [...] Read more.
Studies have shown that the agricultural expansion and land use changes in the Midwest of the U.S. are major drivers for increased nonpoint source pollution throughout the regional river systems. In this study, we empirically examined the relationship of planted area and production of three dominant crops with nitrate flux in the Republican River, Kansas, a sub-watershed of Mississippi River Basin. Our results show that land use in the region could not explain the observed changes in nitrate flux in the river. Instead, after including explanatory variables such as precipitation, growing degree days, and well water irrigation in the regression model we found that irrigation and spring precipitation could explain >85% of the variability in nitrate flux from 2000 to 2014. This suggests that changes in crop acreage and production alone cannot explain variability in nitrate flux. Future agricultural policy for the region should focus on controlling both the timing and amount of fertilizer applied to the field to reduce the potential leaching of excess fertilizer through spring time runoff and/or over-irrigation into nearby river systems. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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9 pages, 1595 KiB  
Article
Source Apportionment of Polycyclic Aromatic Hydrocarbons in Sediment by the Application of Non-Negative Factor Analysis: A Case Study of Dalian Bay
by Fu-Lin Tian, Fa-Yun Li, De-Gao Wang and Yan-Jie Wang
Int. J. Environ. Res. Public Health 2018, 15(4), 761; https://doi.org/10.3390/ijerph15040761 - 16 Apr 2018
Cited by 5 | Viewed by 3715
Abstract
An improved method, factor analysis with non-negative constraints (FA-NNC) was adopted to apportion the sources of sediment polycyclic aromatic hydrocarbons (PAHs) in Dalian Bay, China. Cosine similarity and Monte Carlo uncertainty analysis were used to assist the FA-NNC source resolution. The results identified [...] Read more.
An improved method, factor analysis with non-negative constraints (FA-NNC) was adopted to apportion the sources of sediment polycyclic aromatic hydrocarbons (PAHs) in Dalian Bay, China. Cosine similarity and Monte Carlo uncertainty analysis were used to assist the FA-NNC source resolution. The results identified three sources for PAHs, which were overall traffic, diesel engine emissions and residential coal combustion. The contributions of these sources were quantified as 78 ± 4.6% from overall traffic, 12 ± 3.2% from diesel engine emissions, and 10 ± 1.9% from residential coal combustion. The results from the Monte Carlo uncertainty analysis indicated that the model was robust and convergent. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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Review

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24 pages, 717 KiB  
Review
Erosion and Sediment Transport Modelling in Shallow Waters: A Review on Approaches, Models and Applications
by Mohammad Hajigholizadeh, Assefa M. Melesse and Hector R. Fuentes
Int. J. Environ. Res. Public Health 2018, 15(3), 518; https://doi.org/10.3390/ijerph15030518 - 14 Mar 2018
Cited by 73 | Viewed by 8481
Abstract
The erosion and sediment transport processes in shallow waters, which are discussed in this paper, begin when water droplets hit the soil surface. The transport mechanism caused by the consequent rainfall-runoff process determines the amount of generated sediment that can be transferred downslope. [...] Read more.
The erosion and sediment transport processes in shallow waters, which are discussed in this paper, begin when water droplets hit the soil surface. The transport mechanism caused by the consequent rainfall-runoff process determines the amount of generated sediment that can be transferred downslope. Many significant studies and models are performed to investigate these processes, which differ in terms of their effecting factors, approaches, inputs and outputs, model structure and the manner that these processes represent. This paper attempts to review the related literature concerning sediment transport modelling in shallow waters. A classification based on the representational processes of the soil erosion and sediment transport models (empirical, conceptual, physical and hybrid) is adopted, and the commonly-used models and their characteristics are listed. This review is expected to be of interest to researchers and soil and water conservation managers who are working on erosion and sediment transport phenomena in shallow waters. The paper format should be helpful for practitioners to identify and generally characterize the types of available models, their strengths and their basic scope of applicability. Full article
(This article belongs to the Special Issue Non-Point Source Pollution and Environmental Assessment)
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