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Integration of GIS in the Development of an Environmental Cadastre Administrative System for the Environment Protection Agency Sierra Leone
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作者 Samuel Mohamed Kamara 《Journal of Geographic Information System》 2019年第4期411-428,共18页
The Environment Protection Agency Sierra Leone (EPA) is mandated by law to issue Environmental Impact Assessment license. Currently the agency achieves this mandate by issuing environmental licenses manually which alw... The Environment Protection Agency Sierra Leone (EPA) is mandated by law to issue Environmental Impact Assessment license. Currently the agency achieves this mandate by issuing environmental licenses manually which always encountered lot of problems of accountability and transparency of the management of environmental licenses and assessment documentation. Client’s information and documentation is usually mixed up while carrying files from one point to the other or from one staff to another. Data on client are stored in a way which makes it difficult for the management to retrieve useful information on time. This paper explores these challenges faced by the manual system of issuing environmental licenses and infer solutions to the current challenges by integrating a Geographic Information Systems (GIS) to develop an Environmental Cadastre administrative System (ECAS) which establishes a web-based information repository database developed with open sources software (Java, PHP, MySQL, QGIS) that published revenues online and made the data available to stakeholders and/or the public to complete the cycle of accountability and transparency. The information is presented and downloadable in a comprehensible and user-friendly manner, which in turn improves monitoring and reporting, and increases effectiveness and accountability of the management of environmental licenses and assessment documentation. The findings show these challenges facing the manual system, the back and forth between EPA and the client in the EIA process, the difficulty in the searching a client record, the mixing up of Client’s information and documentation by carrying files from one point to the other, and the storage of data on client in a way which makes it difficult for the management to retrieve useful information on time, and lack of back up when data or information is lost. Problems encountered in the time-consuming nature of the manual retrieval of files and preparation of prompt and accurate reports make it become a difficult task to accomplish as data and information are difficult to retrieve or collect from various files. Based on these findings, this paper provides the possible solution to the above problems. An online Environmental Cadastre administrative System (ECAS) which establishes a web-based information repository database was designed to capture the full lifecycle of environmental licenses including all stages of monitoring, licenses and payments and seamlessly manage the environmental impact assessment (EIA) licenses. 展开更多
关键词 ENVIRONMENTAL Cadastre ADMINISTRATIVE System ENVIRONMENTAL LICENSE GIS ENVIRONMENTAL Impact Assessment Environment PROTECTION AGENCY
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Advancing the Understanding of Environmental Transformations, Bioavailability and Effects of Nanomaterials, an International US Environmental Protection Agency—UK Environmental Nanoscience Initiative Joint Program
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作者 Mitch M.Lasat Kian Fan Chung +5 位作者 Jamie Lead Steve McGrath Richard J.Owen Sophie Rocks Jason Unrine Junfeng Zhang 《Journal of Environmental Protection》 2018年第4期385-404,共20页
Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and ... Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United Kingdom (UK) Environmental Nanoscience Initiative and the United States (US) Environmental Protection Agency have developed an international research program to enhance the knowledgebase and develop risk-predicting models for manufactured nanoparticles. Here we report selected highlights of the program as it sought to maximize the complementary strengths of the transatlantic scientific communities by funding three integrated US-UK consortia to investigate the transformation of these nanoparticles in terrestrial, aquatic, and atmospheric environment. Research results demonstrate there is a functional relationship between the physicochemical properties of environmentally transformed nanomaterials and their effects and that this relationship is amenable to modeling. In addition, the joint transatlantic program has allowed the leveraging of additional funding, promoting transboundary scientific collaboration. 展开更多
关键词 AQUATIC Environment Consumer Products Manufactured NANOMATERIALS Predictive Models Terrestrial Ecosystem
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Global projections of future landslide susceptibility under climate change
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作者 Yu Duan Mingtao Ding +5 位作者 Yufeng He Hao Zheng Ricardo Delgado-Téllez Sergey Sokratov Francisco Dourado Sven Fuchs 《Geoscience Frontiers》 2025年第4期373-386,共14页
Landslides pose a significant threat to both human society and environmental sustainability,yet,their spatiotemporal evolution and impacts on global scales in the context of a warming climate remain poorly understood.... Landslides pose a significant threat to both human society and environmental sustainability,yet,their spatiotemporal evolution and impacts on global scales in the context of a warming climate remain poorly understood.In this study,we projected global landslide susceptibility under four shared socioeconomic pathways(SSPs)from 2021 to 2100,utilizing multiple machine learning models based on precipitation data from the Coupled Model Intercomparison Project Phase 6(CMIP6)Global Climate Models(GCMs)and static metrics.Our results indicate an overall upward trend in global landslide susceptibility under the SSPs compared to the baseline period(2001–2020),with the most significant increase of about 1%in the very far future(2081–2100)under the high emissions scenario(SSP5-8.5).Currently,approximately 13%of the world’s land area is at very high risk of landslide,mainly in the Cordillera of the Americas and the Andes in South America,the Alps in Europe,the Ethiopian Highlands in Africa,the Himalayas in Asia,and the countries of East and South-East Asia.Notably,India is the country most adversely affected by climate change,particularly during 2081–2100 under SSP3-7.0,with approximately 590 million people—23 times the global average—living in areas categorized as having very high susceptibility. 展开更多
关键词 Landslide susceptibility CMIP6 Climate change Spatiotemporal analysis Ensemble modeling
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Emission fluxes of nitrous acid(HONO)from livestock and poultry wastes
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作者 Wenjin Zhang Pengfei Liu +11 位作者 Min Song Xuran Li Xiaoxi Zhao Yifei Song Di Tian Chenglong Zhang Yuanyuan Zhang Yangang Ren Chengtang Liu Junfeng Liu Yinchang Feng Yujing Mu 《Journal of Environmental Sciences》 2025年第10期466-473,共8页
Gaseous nitrous acid(HONO)is a critical contributor to daytime hydroxyl radical in the troposphere.Livestock farming has been recognized as an overlooked HONO source,but the lack of detailed flux measurements from liv... Gaseous nitrous acid(HONO)is a critical contributor to daytime hydroxyl radical in the troposphere.Livestock farming has been recognized as an overlooked HONO source,but the lack of detailed flux measurements from livestock and poultry wastes would cause uncertainties in modeling its environmental impacts.Here,based on field flux measurements and laboratory experiments,we observed substantial HONO emissions from the composting of swine feces and chicken manure in the warm season,which might be mainly attributed to nitrification process in livestock and poultry wastes.The HONO emission from chicken manure was found to bemuch higher than that from swine feces,and the higher NH3 emission but lower N2O and NO emissions fromchicken manurewere also observed.Considering that the interaction among these nitrogen species during nitrification process,the obviously lower HONO emission from swine feces was likely to be explained by the lack of the total ammonia nitrogen and H+donors in swine feces.Temperature is also a key factor that influences the HONO emission from livestock wastes.In addition,the total HONO emission from swine feces in Chinawas estimated to be approximately 107.7 Gg-N/yr according to the national swine amounts,which is comparable to the national soil HONO emissions,underscoring its non-negligible contribution to regional air quality.Therefore,effective emission control of HONO fromlivestock and poultry wastes should be carried out to further improve air quality in China. 展开更多
关键词 Nitrous acid(HONO) Flux measurements Livestock and poultry wastes Open-top dynamic chamber Air pollution
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Characteristics and environmental significance of rare earth elements in PM2.5 of Nanchang, China 被引量:9
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作者 ZHAO Yang YU Ruilian +2 位作者 HU Gongren LIN Xiaohui LIU Xianrong 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第1期98-106,共9页
Concentrations of sixteen rare earth elements(REEs) in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry(ICP-MS).... Concentrations of sixteen rare earth elements(REEs) in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry(ICP-MS). The results showed that the concentrations of total REEs(ΣREE) ranged from 78.76 to 1351 ng/mg. The order of REEs in PM2.5 samples showed the anthropogenic effects, Ce and Eu were affected more than the other REEs according to the enrichment factors. The results of chondrite-normalized REEs patterns and characteristic parameters showed evident light REEs fractionation, and positive anomalies of Ce and Eu in PM2.5. The other non-local pollution sources affected the PM2.5 samples, according to the triangular diagram of La, Ce and Sm compositions and plot of ΣREE vs δEu. Moreover, plot of(La/Sm)N vs(Gd/Yb)N revealed the effects of local sources. In conclusion, the REEs in potential-source samples were close to the background of local soil, while the REEs in PM2.5 samples in Nanchang city were jointly affected by the investigated local sources and other non-local sources. 展开更多
关键词 PM2.5 rare earth elements composition characteristics distribution pattern enrichment factor
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Suspended particulate mercury associated with tidal fluxes in a lagoon environment impacted by cinnabar mining activity(northern Adriatic Sea) 被引量:1
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作者 Alisè Turritto Alessandro Acquavita +5 位作者 Annelore Bezzi Stefano Covelli Giorgio Fontolan Elisa Petranich Raffaella Piani Simone Pillon 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第6期100-113,共14页
The Isonzo River has been demonstrated to be a continuing point source of mercury(Hg)in the Gulf of Trieste although the Idrija mine was last active in 1996. The present study aims to investigate the role of the sus... The Isonzo River has been demonstrated to be a continuing point source of mercury(Hg)in the Gulf of Trieste although the Idrija mine was last active in 1996. The present study aims to investigate the role of the suspended particulate matter(SPM) associated with tidal fluxes to disperse particulate Hg(PHg) into the Grado coastal lagoon system. PHg concentrations(avg. 3.11 ± 2.62 μg/g, d.w.), notwithstanding the ebb or flood tides, were significantly higher than the local sediment background(0.13 μg/g). The relative affinity of Hg for the particulate phase in surface waters was confirmed by higher average distribution coefficient(Kd) values(5.6–6.7). PHg contents showed the highest values in ebb tide conditions, thus suggesting their origin from the erosion of tidal flats and saltmarshes of the lagoon. When compared to river discharge, high PHg surface concentrations in flood tide are related to rainfall events occurring within the river basin. Results can be used to make an indicative assessment of the amount of Hg bound to SPM which is transported in and out of the lagoon basin following the action of tidal fluxes. A simple estimation provides a negative budget for the Grado lagoon sub-basin which loses between 0.14 and 1.16 kg of PHg during a tidal semi-cycle. This conclusion is in agreement with the evidence of morphological deterioration which has emerged from recent studies on the lagoon environment, and which testifies to a current sedimentary loss from the lagoon into the northern Adriatic Sea. 展开更多
关键词 MERCURY Tidal fluxes Suspended particulate matter LAGOON
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Biological transformation,kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure
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作者 M A Mottaleb J H Zimmerman T W Moy 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期878-884,共7页
Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other environment.Thus,aquatic organisms can be continuously exp... Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other environment.Thus,aquatic organisms can be continuously exposed to MK.In this study,kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite,bound to cysteine-hemoglobin (Hb) in rainbow trout,formed by enzymatic nitro-reduction of MK have been demonstrated.Trout were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg MK/g fish.Tw... 展开更多
关键词 BIOTRANSFORMATION KINETICS hemoglobin adducts DOSE-RESPONSE nitro musks BIOMARKER fish
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Effect of environmental factors on the effectiveness of ammoniated bagasse in wicking oil from contaminated wetlands
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作者 Seungjoon Chung Makram T.Suidan Albert D.Venosa 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第8期1371-1377,共7页
Ammoniated bagasse is a plant-derived organic sorbent that can be used for capturing oil and for supplying slow-release nutrients to oil-degrading microorganisms. We investigated the oil-wicking behavior of this sorbe... Ammoniated bagasse is a plant-derived organic sorbent that can be used for capturing oil and for supplying slow-release nutrients to oil-degrading microorganisms. We investigated the oil-wicking behavior of this sorbent under various conditions for its effectiveness in remediating oil-contaminated wetlands. Abiotic microcosms simulating a wetland environment were used to assess the influence of sand particle sizes (20x30 and 60x80 U.S. mesh), degrees of oil saturation (25% and 75%), water table levels (on top of the clean sand layer, oiled-sand layer, and sorbent layer), and the presence of sorbent. Results indicated that oil wicking favors higher oil contamination, larger sand particle size, and low water coverage. Water coverage was the predominant factor limiting the effectiveness of sorbent. The most plausible explanation for this limitation was that sorbent captured more water than oil at higher water coverage. 展开更多
关键词 crude oil WETLANDS SORBENT REMEDIATION sediment
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Environmental Evaluation of Springs in the Intensely Cultivated and Industrialized Inland Plain of Cuneo (Northwest Italy)
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作者 Maurizio Battegazzore Angelo Morisi 《Journal of Environmental Science and Engineering(A)》 2012年第1期19-24,共6页
Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis (PCA) of all the data was undertaken. The first principal component was positively c... Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis (PCA) of all the data was undertaken. The first principal component was positively correlated with chlorides, sulphites, hardness, and negatively correlated with altitude. The second principal component was positively correlated with DO and pH. Results showed that 4 groups of springs could be distinguished on the basis of environmental variables. A small number of springs did not group with the geographically more proximal springs but with another group due to a greater degree of affinity on the basis of the hydrochemical variables. 展开更多
关键词 SPRINGS groundwater quality Cuneo plain.
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Development of a Geographic Information Systems Baseline Spatial Geodatabase Template for Evaluating Potential and Predicted Environmental Impacts for Sustainable Environmental Impact Assessment of Mining in Sierra Leone
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作者 Samuel Mohamed Kamara 《Journal of Geoscience and Environment Protection》 2020年第10期262-284,共23页
Baseline Environmental Impact Assessment (EIA) of mining projects in Sierra Leone creates a challenging environment for data collection and impact prediction. Application of geographic information systems provides sui... Baseline Environmental Impact Assessment (EIA) of mining projects in Sierra Leone creates a challenging environment for data collection and impact prediction. Application of geographic information systems provides suitable spatial analysis data collection methods to reduce the challenges created by mining environments. This research develops a baseline spatial geodatabase template for evaluating potential and predicted environmental impacts assessment of mining projects in Sierra Leone. It is observed that spatial analysis of impacts of mining projects on the environmental attributes, especially air, noise, water, land, and socio-economy in mining areas is largely unexplored in Sierra Leone. The literature review revealed that no complete GIS spatial data geodatabase collection template appears to have been developed to date to provide an integrated sustainable spatial analysis and modelling tool for EIA and environmental management of mining in Sierra Leone. Therefore developing a Geographic Information Systems baseline geodatabase template for the evaluation of potential and predicted environmental impact for sustainable environmental impact assessment of mining in Sierra Leone will: 1) provide support to the data acquisition process of environmental impact assessment, 2) offer a concept for developing analysis methods for environmental management of mining, 3) minimize the undesired environmental impacts of mining, and 4) give an optimal proposal for data collection and analysis of mining industry in attaining sustainable development in Sierra Leone. Due to the limited available data, a conceptual GIS database template has been developed rather than a database case study of a mining site. No site investigation and data collection were undertaken. The geospatial database template was designed using ArcCatalog, ArcGIS 10.7.1. software, through the following steps: exploration of the general data requirement of environmental impact assessment studies of mining, the definition of the general baseline datasets requirement of environmental impact assessment in mining, structuring of the environmental impact assessment baseline spatial geodatabase, creating the geographic geodatabase dictionary, selecting, matching geographic data with geodatabase structure, designing the feature class and attributes, creating the baseline GIS geodatabase template. The GIS spatial geodatabase template has several advantages for environmental impact assessment of mining including avoiding data redundancy, integrating data into a single database, creating uniformity in data collection, easy to find and track data, integrated spatial and non-spatial data, and reducing the volume of data. 展开更多
关键词 GIS Environmental Impact Assessment Spatial Geodatabase Sustainable Environment
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Use of Environmental Sequence Stratigraphy (ESS) as an Environmental Forensic Tool to Identify Chlorinated Solvent Sources at a Complex Site in Silicon Valley, California
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作者 Rick Cramer Jun Lu +2 位作者 Mike Shultz Colin Plank Herb Levine 《Journal of Environmental Protection》 2018年第5期554-566,共13页
This paper presents a case study for a complex contaminated groundwater site impacted by a historical release of chlorinated solvents in Silicon Valley, California. The original conceptual site model (CSM) inferred a ... This paper presents a case study for a complex contaminated groundwater site impacted by a historical release of chlorinated solvents in Silicon Valley, California. The original conceptual site model (CSM) inferred a contaminant migration pathway based on the groundwater gradient interpreted from groundwater elevation data, which is based on the underlying assumption that the subsurface conditions are homogeneous. However, the buried channel deposits render the underlying geology highly heterogeneous, and this heterogeneity plays a significant role in the subsurface migration of contaminants. Chemical fingerprinting evidence suggested that contamination at the downgradient property boundary was related to an off-site contaminant source. But, this alone was not a compelling argument. However, Environmental Sequence Stratigraphy (ESS), a geology-based environmental forensic technique, was applied to define the permeability architecture or the “plumbing” that controls subsurface fluid flow and contaminant migration. First, the geologic and depositional setting was synthesized based on regional geologic data, and representative facies models were identified for the site. Second, the existing CSM and site lithology data were reviewed and existing lithology data were graphically presented to display vertical grain-size patterns. This analysis focused on the nexus between the depositional environment and the site-specific subsurface data resulting in correlations/interpretations between and beyond data points that are based on established stratigraphic principles. The depositional environment results in buried river channels as the primary control on subsurface fluid flow, which defines hydrostratigraphic units (or HSUs). Finally, a hydrostratigraphic CSM that includes maps and cross sections was constructed to depict the HSUs present as a framework to integrate hydro-geology and chemistry data. This study demonstrates that: 1) Highly per-meable buried river channel deposits control subsurface fluid flow and contaminant transport, and have distinct chemical constituents and concentrations (i.e., they represent distinct HSUs), 2) Mapping of such HSUs is feasible with existing boring log data, 3) In settings such as the Santa Clara Valley where groundwater flow is governed by subsurface channel deposits, a hydrostratigraphic mapping approach is superior to a depth-based aquifer zonation approach, and 4) For heterogeneous subsurface, a detailed geology-based definition of the subsurface is an integral component of an environmental forensic analyses to determine contaminant source(s) and pathways. 展开更多
关键词 ENVIRONMENTAL Sequence Stratigraphy Hydrostratigraphic Units HSU Contaminant SOURCES Source Identification Migration Pathways DEPOSITIONAL Environment Chlorinated Solvents ENVIRONMENTAL Forensic TOOL
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Natural Environment and Landscape Energy of Western Georgia
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作者 Zurab Seperteladze Eter Davitaia +3 位作者 Tariel Kikvadze George Gaprindashvili Tamar Aleksidze Nino Rukhadze 《Natural Resources》 CAS 2023年第1期1-12,共12页
The particularly great practical importance of modern physical geography and, in particular, landscape science, is first of all manifested in the detection and study of the resource potential of landscapes, as well as... The particularly great practical importance of modern physical geography and, in particular, landscape science, is first of all manifested in the detection and study of the resource potential of landscapes, as well as in the optimization of the environment. The resource potential, on the other hand, greatly depends on the balance of substance and energy exchange in the natural resources, i.e. the energy of the landscape. In this case, one of the important things is to study the functioning of natural-territorial complexes (NTC). Through it, it is possible and relatively easy to explain, model and, most importantly, predict many complex processes taking place in NTC, including the role of landscape energy balance in increasing the productivity and yield of agro-landscapes, which was the first attempt to research this problem in Georgia. 展开更多
关键词 Landscape Energy Agro-Landscape OPTIMIZATION Solar Radiation Energy Balance
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Environmental Studies on the Aqaba Gulf Coastal Waters during 2011-2013
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作者 Ahamed M. Abdel-Halim Mohamed A. Aly-Eldeen +5 位作者 Laila M. Abdel Fattah Mamdouh A. Fahmy Ehssan M. Abo-El-Khair Azza M. Khaled Ahamed Abu El-Soud Mohamed A. Shreadah 《Journal of Environmental Protection》 2016年第10期1411-1437,共28页
In order to assess the quality of the Aqaba Gulf coastal waters for the sustainable use and development, and consequently for the national income, four field campaigns were annually carried out during the period from ... In order to assess the quality of the Aqaba Gulf coastal waters for the sustainable use and development, and consequently for the national income, four field campaigns were annually carried out during the period from 2011-2013 to monitor hydrographic variables, i.e. temperature, salinity, pH, etc., nutrients, some heavy metals, i.e. iron, lead, copper, cadmium, chromium, etc. in addition to petroleum hydrocarbons. Except for the area of Sharm El-Sheikh Harbor, the results for the density, composition, and distributions of beach litter cleared out that the Egyptian shoreline of the Aqaba Gulf is relatively not affected by man-made litter. The area of Sharm El-Sheikh Harbor was subjected to many factors which undoubtedly affected the rate of man-made litter ac-cumulation, especially, oil contamination (oil and old or new tar) which is a good es-timator of levels of oil contamination and an effective means of evaluating the poten-tial threat of oil on coastal resources. The results of the present study cleared out also that water temperature followed seasonal changes in air temperature. Aqaba Gulf water is characterized by its high salinity and the presence of well oxygenated waters. Minor changes in the distribution of pH, BOD, DOM and COD, revealed limited effects of human impacts. Low levels of Chl-a and TSM concentrations and high transparency revealed also negligible effects for human impacts. Significantly higher sea water temperatures, TSM, DO, BOD, DOM, COD, NH<sub>4</sub>, NO2, PO<sub>4</sub> and TP were observed in summer season compared to their corresponding values in winter season. On contrast, higher values of chlorophyll-a, NO2, TN, and SiO<sub>4</sub> were observed in winter compared to summer season. Based on the mean annual values, Aqaba Gulf coastal waters are classified as oligotrophic to mesotrophic state. The concentrations of dissolved inorganic nitrogen forms followed the following order: NH<sub>4</sub>= NO<sub>3</sub>>NO2. In general, the majority of TN in winter was in the form of organic-N (96.3%) compared to 91.7% in summer season. On the meantime, TP exhibited more or less comparable organic-P percentage in summer (86.2%) and winter (81.2%) seasons. Moreover, the DIN/DIP ratio showed relatively higher values in winter season (14.2:1) compared to summer season (12.4:1). This indicates high nitrogen concentrations in comparison with that of phosphorous in winter;yet it reflects the generally lower nutrient levels present in the coastal waters of the Aqaba Gulf due to the lack of significant nutrient input or oceanic upwelling. Concentrations of heavy metals were relatively low signifying that Aqaba Gulf Coastal waters are not yet seriously threatened in spite of the rapid recreational and human developments that are considered a challenge to the safety and viability of Aqaba Gulf marine environment. Furthermore, concentrations of petroleum hydrocarbons were significantly higher in summer than in winter that are mainly attributed to the increase in the levels of oil pollution that most probably re-sulted from the increase in accidental, deliberate or operational discharges and spills of oil from ships. In general, the maximum concentration was much lower than the harmful concentrations reported for seawater. A stepwise multiple linear regression, analysis of variance (ANOVA), and principle component analysis (PCA) were applied. 展开更多
关键词 Physicochemical Properties NUTRIENTS Heavy Metals Petroleum Hydrocarbons Coastal Water Gulf of Aqaba
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Seasonal variations in dissolved organic matter concentration and composition in an outdoor system for bank filtration simulation 被引量:3
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作者 Muhammad Zeeshan Omamah Ali +1 位作者 Shamas Tabraiz Aki Sebastian Ruhl 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期252-261,共10页
Dissolved organic matter(DOM)in surface waters can vary markedly in character depending on seasonal variations such as rainfall intensity,UV radiations and temperature.Changes in DOM as well as temperature and rainfal... Dissolved organic matter(DOM)in surface waters can vary markedly in character depending on seasonal variations such as rainfall intensity,UV radiations and temperature.Changes in DOM as well as temperature and rainfall intensity over the year can affect the biochemical processes occurring in bank filtration(BF).Identification and characterization of DOM in the surface water could help to optimize the water treatment and provide stable and safe drinking water.This study investigated year-long variations of DOM concentrations and compositions in a surface water of a circulated outdoor pond(research facility)connected to a BF passage.DOM was dominated by humic substances and a changing pattern of DOM in surface water was observed throughout the year.A significant increase of DOM(~38%)in surface water was noted in August compared to November.The fluorescent DOM showed that DOM in summer was enriched with the degradable fraction whilst non-degradable fraction was dominated in winter.A constant(1.7±0.1 mg/L)effluent DOM was recirculated in the system throughout the year.DOM removal through BF varied between 4%to 39%and was achieved within a few meters after infiltration and significantly correlated with influent DOM concentration(R^(2)=0.82,p<0.05).However,no significant(p>0.05)change in the removal of DOM was observed in two subsurface layers(upper and lower).This study highlights the presence of a constant non-degradable DOM in the bank filtrate,which was not affected by temperature,redox conditions and UV radiations. 展开更多
关键词 Bank filtration Dissolved organic matter Dissolved oxygen Fluorescence spectroscopy Excitation-emission matrix
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An exploration of meteorological effects on PM_(2.5) air quality in several provinces and cities in Vietnam 被引量:1
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作者 Giang Tran Huong Nguyen Luan Thien La +1 位作者 Huy Hoang-Cong Anh Hoang Le 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第11期139-151,共13页
Linking meteorology and air pollutants is a key challenge.The study investigated meteorological effects on PM_(2.5)concentration using the advanced convergent cross mapping method,utilizing hourly PM_(2.5)concentratio... Linking meteorology and air pollutants is a key challenge.The study investigated meteorological effects on PM_(2.5)concentration using the advanced convergent cross mapping method,utilizing hourly PM_(2.5)concentration and six meteorological factors across eight provinces and cities in Vietnam.Results demonstrated that temperature(ρ=0.30)and radiation(ρ=0.30)produced the highest effects,followed by humidity(ρ=0.28)and wind speed(ρ=0.24),while pressure(ρ=0.22)and wind direction(ρ=0.17)produced the weakest effects on PM_(2.5)concentration.Comparing theρvalues showed that temperature,wind speed,and wind direction had greater impacts on PM_(2.5)concentration during the dry season whereas radiation had a more influence during the wet season;Southern stations experienced larger meteorological effects.Temperature,humidity,pressure,and wind direction had both positive and negative influences on PM_(2.5)concentration,while radiation and wind speed mostly had negative influences.During PM_(2.5)pollution episodes,there wasmore contribution ofmeteorological effects on PM_(2.5)concentration indicated byρvalues.At contaminated levels,humidity(ρ=0.45)was the most dominant factor affecting PM_(2.5)concentration,followed by temperature(ρ=0.41)and radiation(ρ=0.40).Pollution episodes were pointed out to be more prevalent under higher humidity,higher pressure,lower temperature,lower radiation,and lower wind speed.Theρcalculation also revealed that lower temperature,lower radiation,and higher humidity greatly accelerated each other under pollution episodes,further enhancing PM_(2.5)concentration.The findings contributed to the literature on meteorology and air pollution interaction. 展开更多
关键词 Fine particulate matter Air pollution Meteorological effect Convergent cross mapping Causality analysis VIETNAM
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Periodic Addition of Glucose Suppressed Cyanobacterial Abundance in Additive Lake Water Samples during the Entire Bloom Season
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作者 David Linz Ian Struewing +6 位作者 Nathan Sienkiewicz Alan David Steinman Charlyn Gwen Partridge Kyle McIntosh Joel Allen Jingrang Lu Stephen Vesper 《Journal of Water Resource and Protection》 CAS 2024年第2期140-155,共16页
Previously, we showed that prophylactic addition of glucose to Harsha Lake water samples could inhibit cyanobacteria growth, at least for a short period of time. The current study tested cyanobacterial control with gl... Previously, we showed that prophylactic addition of glucose to Harsha Lake water samples could inhibit cyanobacteria growth, at least for a short period of time. The current study tested cyanobacterial control with glucose for the entire Harsha Lake bloom season. Water samples (1000 ml) were collected weekly from Harsha Lake during the algal-bloom season starting June 9 and lasting until August 24, 2022. To each of two 7-liter polypropylene containers, 500 ml of Harsha Lake water was added, and the containers were placed in a controlled environment chamber. To one container labeled “Treated,” 0.15 g of glucose was added, and nothing was added to the container labeled “Control.” After that, three 25 ml samples from each container were collected and used for 16S rRNA gene sequencing each week. Then 1000 ml of Harsha Lake water was newly collected each week, with 500 ml added to each container, along with the addition of 0.15 g glucose to the “Treated” container. Sequencing data were used to examine differences in the composition of bacterial communities between Treated and Control containers. Treatment with glucose altered the microbial communities by 1) reducing taxonomic diversity, 2) largely eliminating cyanobacterial taxa, and 3) increasing the relative abundance of subsets of non-cyanobacterial taxa (such as Proteobacteria and Actinobacteriota). These effects were observed across time despite weekly inputs derived directly from Lake water. The addition of glucose to a container receiving weekly additions of Lake water suppressed the cyanobacterial populations during the entire summer bloom season. The glucose appears to stimulate the diversity of certain bacterial taxa at the expense of the cyanobacteria. 展开更多
关键词 GLUCOSE CYANOBACTERIA 16S Amplicon Sequencing Microbial Community
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HABS-BLOCKS©, a Floating, Slow-Release Glucose Source, Promoted the Growth of Heterotrophic Bacteria Relative to Toxic Cyanobacteria in Lake Water Mesocosms
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作者 Stephen Vesper David Linz +1 位作者 Ian Struewing Jingrang Lu 《Journal of Water Resource and Protection》 2024年第12期780-792,共13页
Previously, we demonstrated that the addition of glucose to lake water could alter the composition of the microbial community so that heterotrophic bacteria came to dominate the cyanobacteria. To target the glucose ad... Previously, we demonstrated that the addition of glucose to lake water could alter the composition of the microbial community so that heterotrophic bacteria came to dominate the cyanobacteria. To target the glucose additions to the euphotic zone, a floating, slow-release glucose source, designated HABS-BLOCKS©, was created. HABS-BLOCKS© consist of blocks of pumice stone, vacuum infiltrated with glucose, and covered in layers of soy wax. In this study, the HABS-BLOCKS© were tested in 7-liter mesocosm vessels (n = 4) that received an initial 750 ml of lake water, followed by weekly additions of 500 ml of freshly collected lake water. Three HABS-BLOCKS© were added to each of two replicate mesocosms. For controls, one mesocosm was left untreated and one mesocosm received three “Dummy” HABS-BLOCKS© (contain no glucose). During a ten-week experiment, 25 ml samples were obtained from each mesocosm weekly, which were then filtered, frozen and latter processed for 16S rRNA sequencing. Planktothrix and Cyanobium were the most abundant cyanobacteria in the lake water. Within three weeks of the start of the experiment, the bacterial community in the HABS-BLOCKS© treated mesocosms became dominated by heterotrophic bacteria, e.g., Asticcacaulis, relative to the control mesocosms. Heterotrophic domination in the HABS-BLOCKS© treated mesocosms continued for the rest of the experiment. HABS-BLOCKS© appears to provide a competitive edge for the heterotrophic bacteria that allows them to dominate the toxin-producing cyanobacteria. 展开更多
关键词 GLUCOSE Cyanobacteria 16S Amplicon Sequencing Microbial Community HETEROTROPHS
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The Implementation of Fire Control Measures in Resettlement Farming Areas of Hwedza,Zimbabwe
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作者 Bowora Edmore Maponga Robert 《Journal of Agricultural Science and Technology(A)》 2024年第3期124-135,共12页
Despite fire control in Zimbabwe’s resettlement farming areas,fire continues to damage the environment,property,crops and causes loss of lives.The goal of this paper was to investigate fire control measures implement... Despite fire control in Zimbabwe’s resettlement farming areas,fire continues to damage the environment,property,crops and causes loss of lives.The goal of this paper was to investigate fire control measures implemented by resettled farmers in Hwedza,Zimbabwe.The data used in the study were derived from both primary and secondary sources.Primary research data were obtained through questionnaires and interviews targeting households and key informants.Secondary data were collected from reports and records from relevant government institutions.Chi-square tests were conducted to establish the relationship between fire control measures and fire trends.The research findings show evidence of fire control in the study area with farmers implementing a combination of pre-suppression and suppression fire control measures.The use of fire breaks and fire brigades were the more prevalent pre-suppression measures implemented by 86%and 78%of the farmers respectively.The main fire suppression measures implemented were the use of fire beaters(92%)and dowsing with water(85%).Fire occurrence responded to control measures when burnt area declined by 24.1%for the period 2011-2014 when the number of farmers implementing control measures increased from 131 to 701.A negative association between the number of fires and fire pre-suppression measures;and burnt area and fire suppression measures was found.The study recommends early detection,education and awareness as the primary steps in ensuring effective fire control.Active participation of all responsible stakeholders and the affected farmers is also of importance to effectively manage fire. 展开更多
关键词 FIRE IMPLEMENTATION RESETTLEMENT pre-suppression SUPPRESSION fire control measures fire break fire beater
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不同阴离子对水溶性磷酸盐稳定污染土壤中重金属的影响 被引量:11
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作者 邢维芹 王亚利 +4 位作者 Kirk G Scheckel 李立平 向国强 巩丹丹 史丽兰 《环境科学学报》 CAS CSCD 北大核心 2013年第10期2814-2820,共7页
在重金属污染土壤中加入磷酸盐是稳定重金属的有效方法.本研究的目的是探讨不同阴离子对水溶性磷酸盐稳定污染土壤铅、镉和锌的影响.在重金属复合污染土壤(全铅、镉和锌的含量分别为2337、21.4和391 mg·kg-1)中按P∶Pb=2∶1(mol... 在重金属污染土壤中加入磷酸盐是稳定重金属的有效方法.本研究的目的是探讨不同阴离子对水溶性磷酸盐稳定污染土壤铅、镉和锌的影响.在重金属复合污染土壤(全铅、镉和锌的含量分别为2337、21.4和391 mg·kg-1)中按P∶Pb=2∶1(mol∶mol)加入磷酸二氢钙,之后按P∶阴离子=3∶1或3∶2(mol∶mol)加入盐酸、氯化钠、硫酸、硫酸钠或氟化钠,并设置只加磷酸盐、不加其它试剂的对照,培养55 d,之后测定土壤性质.结果表明,与对照相比,HCl处理、2HCl处理、NaCl处理和2NaCl处理土壤DTPA-Pb含量下降比例依次为5.72%、9.29%、6.38%和8.80%(p〈0.05),加入硫酸、硫酸钠的处理土壤DTPA-Pb含量与对照无显著差异(p〉0.05),而加入氟化钠的处理升高4.70%(p〈0.05).加入盐酸或氯化钠的处理土壤镉有效性显著高于对照(升高5.24%~12.8%)(p〈0.05),其它处理对DTPA-Cd含量无显著影响(p〉0.05).各处理对土壤DTPA-Zn含量和pH影响较小,但均引起土壤电导率明显升高.以上结果表明,氯离子可促进水溶性磷酸盐对土壤铅的稳定,但可促进镉有效性.氯磷酸铅的生成是加氯情况下磷酸盐稳定铅的重要机制. 展开更多
关键词 土壤 阴离子 磷酸盐 稳定
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长江三角洲地区大气O3和PM10的区域污染特征模拟 被引量:92
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作者 李莉 陈长虹 +5 位作者 黄成 黄海英 李作攀 Joshua S. Fu Carey J. Jang David G. Streets 《环境科学》 EI CAS CSCD 北大核心 2008年第1期237-245,共9页
以TRACE-P污染源资料及上海市地方排放清单为基础,采用Models-3/CMAQ环境空气质量模型和中尺度气象模式MM5,模拟研究了2001-01和2001-07长三角近地面二次污染物O3及PM10的浓度分布及输送状况,并以上海市国控点2001年冬、夏季各10 d的小... 以TRACE-P污染源资料及上海市地方排放清单为基础,采用Models-3/CMAQ环境空气质量模型和中尺度气象模式MM5,模拟研究了2001-01和2001-07长三角近地面二次污染物O3及PM10的浓度分布及输送状况,并以上海市国控点2001年冬、夏季各10 d的小时监测数据对模型进行了验证.验证结果显示,Models-3/CMAQ对O3和PM10的模拟结果与监测值的相关系数分别为0.77和0.52;一致性指数分别达到0.81和0.99.模型对O3小时最高浓度的估算偏低27%,标准偏差为-3.1%;对PM10小时平均浓度的估算偏低10%,标准偏差为46%.模型已具备再现和模拟长三角大气污染输送过程的能力,且误差落在可接受的范围之内.模拟结果显示,2001-07长三角区域16个主要城市中,有14个城市O3小时最大浓度超过国家二级标准,高浓度O3可覆盖苏南和浙北广大区域.2001-01泰州、扬州、南京、镇江、常州等城市受本地排放源和北部大气污染输送的影响显著,大气PM10日均浓度超过PM10国家二级标准.长三角地区环境空气质量与污染类型受大气污染传输与化学转化的影响十分明显.夏季太阳辐射较强时,南部城市排放的污染物常以二次污染物的形式影响下风向城市;太阳辐射较弱的情况下,则以一次污染物输送为主的形式影响周边地区.冬季长三角区域颗粒物污染总体水平较高,这与我国北方地区排放的颗粒物在西北风作用下向长三角输送造成的影响密切相关.长三角地区的大气污染已逐渐从局地转为区域问题. 展开更多
关键词 区域污染 污染输送 长江三角洲 空气质量模拟 MODELS-3/CMAQ
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