scholarly journals Risk Assessment Based on Nitrogen and Phosphorus Forms in Watershed Sediments: A Case Study of the Upper Reaches of the Minjiang Watershed

2019 ◽  
Vol 11 (20) ◽  
pp. 5565 ◽  
Author(s):  
Hongmeng Ye ◽  
Hao Yang ◽  
Nian Han ◽  
Changchun Huang ◽  
Tao Huang ◽  
...  
Keyword(s):  
Ecological Risk ◽  
Evaluation Method ◽  
Pollution Index ◽  
Risk Level ◽  
Nutrient Elements ◽  
Nitrogen And Phosphorus ◽  
Phosphorus Forms ◽  
Minjiang River ◽  
Index Evaluation ◽  
Bioavailability Index

In order to achieve effective eutrophication control and ecosystem restoration, it is of great significance to investigate the distribution characteristics of nutrient elements in sediments, and to perform ecological risk assessments. In the current grading criteria for nutrient elements in sediments, only the overall or organic components of carbon, nitrogen and phosphorus are considered, while the specific species distributions and bioavailability characteristics are rarely taken into account. Hence, using the current grading criteria, the differences in the release, migration and biological activity of nutrient elements in sediments cannot be accurately reflected. Taking the upper reaches of the Minjiang River watershed as an example, we analyzed the overall distributions and the ratio of nutrient elements in sediments, the spatial changes of nitrogen and phosphorus forms, the bioavailability, and the environmental significance. The ecological risk of nitrogen and phosphorus in sediments was assessed using an evaluation method based upon the biological effective parameter. The results were compared with the results of the evaluation methods based on the single pollution index, and then these evaluation methods were confirmed accordingly. From the results, the following conclusions can be obtained: (1) The spatial distributions of nutrient elements in sediments in the upper reaches of the Minjiang River Watershed (including the Jianxi Basin, Futunxi Basin, and Shaxi Basin) were significantly affected by the local ecology and the urban sewage discharge system. (2) The maximum average contents of total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) in sediments were observed in the Jianxi Basin, the Futunxi Basin and the Shaxi Basin, respectively. (3) According to the contents of nitrogen and phosphorus in sediments, the bioavailable nitrogen (TTN) accounted for 35.49% of the total contents of TN. The components of TTN can be sorted from high to low as follows: Nitrogen in organic sulfide form (SOEF-N) > nitrogen in iron-manganese oxide form (SAEF-N) > nitrogen in ion exchange form (IEF-N) > nitrogen in weak acid leaching form (WAEF-N). Inorganic phosphorus (IP) was the main component of TP. The components of IP can be sorted from high to low as follows: Metal oxide bound phosphorus (NaOH-P) > calcium bound phosphorus (HCl-P) > reduced phosphorus (BD-P) > weakly adsorbed phosphorus (NH4Cl-P). Meanwhile, bioavailable phosphorus (BAP, BAP = NH4Cl-P + BD-P + NaOH-P) accounted for 36.94% of TP. According to the results of the single pollution index method, the risk level of TOC pollution in the sediments was relatively low in the whole area, while the risk level of TN pollution was low or moderate in most zones, and severe in certain ones. The risk level of TP pollution was low to moderate. (4) From the results of the bioavailability index evaluation method, based on the total amounts and forms of N and P, the risk level of N pollution was moderate, while the risk of P pollution was negligible. In addition, the results of the bioavailability index evaluation method were more consistent with the actual situation and reflected the overall environmental effects of nitrogen and phosphorus.

scholarly journals Monitoring and Ecological Risks of Heavy Metals of Urban Soils in Different Functional Areas Based on Plasma Technology

2022 ◽  
Author(s):  
Meng-Ting Jin ◽  
Hao Yuan ◽  
Quan Xu ◽  
Li-Ping Xu ◽  
De-Zheng Yang
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
River Basin ◽  
Ecological Risk ◽  
Metal Content ◽  
Pollution Index ◽  
Heavy Metal Content ◽  
Risk Level ◽  
Manas River Basin ◽  
Functional Areas

Abstract Heavy metal pollution in soil has become a global environmental problem in recent years. This study assessed heavy metals' pollution distribution, level and ecological risk in soils from different functional areas in Shihezi City, China. Heavy metals (Cr, Cu, Pb, Zn, Ni, and Cd) were measured using atmospheric pressure discharge plasma and inductively coupled plasma mass spectrometer. The mean concentration of all heavy metals in soil was higher than heavy metals' background values. The spatial distribution of Cr is the most different, and the distribution of Cu and Zn are similar in other functional regions. The single pollution index indicated that the heavy metals in industrial, traffic, and residential areas were enriched, and the pollution of Cd was more severe than others. The Nemerow pollution index showed that the near Manas River basin coast is alert (still clean), the industrial area is moderately polluted, and all other functional areas are lightly polluted. The potential ecological risk index demonstrated that only the nearshore Manas River Basin is at a mild ecological risk level, while all other functional areas are at a moderate ecological risk level. The determinate power of DEM, temperature, and precipitation were all over 65%, which meant that the topographic and climatic factors were the main factors affecting the change of heavy metal content. Secondly, socio-economic factors are important factors to promote the change of heavy metal content in soil.

scholarly journals Study on Pollution Status of Cd, As, Hg and Pb in Rural Soils

2019 ◽  
Vol 118 ◽  
pp. 04002
Author(s):  
Na Wang
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Ecological Risk ◽  
Ecological Risk Assessment ◽  
Pollution Index ◽  
Potential Ecological Risk ◽  
Single Factor ◽  
Potential Ecological Risk Assessment ◽  
Sampling Points ◽  
Index Evaluation

The contents of heavy metals Cd, As, Hg and Pb in rural soils of Zhashui County (Zhujiawan Village, Xingping Village and Zhongping Village) were determined.. The results showed that the contents of Cd, As and Pb in some sampling points were Slightly higher than the background value of soil elements in Shaanxi. The single factor pollution index evaluation, the ground cumulative pollution index evaluation and the potential ecological risk assessment indicated that the heavy metals in the soil showed mild pollution at some sampling points.

scholarly journals The Content and Sources of Potentially Toxic Elements in the Road Dust of Surgut (Russia)

Atmosphere ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 30
Author(s):  
Dmitriy Moskovchenko ◽  
Roman Pozhitkov ◽  
Andrey Soromotin ◽  
Valeriy Tyurin
Keyword(s):  
Particle Size ◽  
Enrichment Factor ◽  
Ecological Risk ◽  
Pollution Index ◽  
Road Dust ◽  
Size Composition ◽  
Risk Level ◽  
Contamination Assessment ◽  
The Road ◽  
Particle Size Composition

The chemical and particle size composition of road dust in Surgut, which is a rapidly developing city in Western Siberia, was studied for the first time. Contents of major and trace elements were determined using ICP-MS and ICP-AES, respectively. It was found that the road dust had an alkaline pH (from 7.54 to 9.38) and that the particle size composition was dominated by the 100–250-μm fraction. The contamination assessment based on calculations of the enrichment factor (EF) showed that the road dust was significantly enriched in Sb and Cu and moderately enriched in Zn, Pb, Mo, Ni and W. The sources of these elements are probably associated with the abrasion of car tires and brake pads. Based on calculations of global pollution index (PIr) and total enrichment factor (Ze), the road dust of Surgut was characterized by a generally low level of potential ecological risk, except for stretches of road subject to regular traffic jams, where a moderate ecological risk level was identified. In comparison to the other Russian cities (Moscow, Chelyabinsk, Tyumen, etc.) where studies of road dust composition have been carried out, Surgut had similar contents of Cr and Cu and relatively lower contents of Sb, Cd, As and Pb.

scholarly journals Analysis and Evaluation on Characteristics of Heavy Metal Pollution in the Coastal Farmland Soil along the Wuma River

2021 ◽  
Vol 20 (4) ◽  
Author(s):  
Xiongfei Cai ◽  
Die Xu ◽  
Shijie Zhao ◽  
Li Lei ◽  
Ji Wang ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Ecological Risk ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Pollution Index ◽  
Guizhou Province ◽  
Risk Level ◽  
Index Method ◽  
Farmland Soil

The thesis is aimed to provide a reference for the sustainable utilization of farmland soils along the Wuma River, an upstream tributary of the Chishui River in Guizhou Province. Geo accumulation index method, Nemero comprehensive pollution index method, and potential ecological hazard index method were used based on the experimental data for analyzing and evaluating the heavy metal pollution status of farmland soil along Wuma River. The results showed that: (1) The contents of heavy metals Ni, Cu, Zn, Pb and Hg in farmland soil exceeded the soil background values of 9.82%, 47.80%, 13.72% and 76.06% in Guizhou Province, respectively, but did not exceed the standard limit class II based on the environmental quality. (2). The pollutants of Pb and Zn in the research area mainly come from mineral exploitation, waste residue accumulation, and transportation. The enrichment of Cr and Cu may originate from the domestic garbage dumping and incinerated waste by residents along the coast and irrational agricultural activities. The main contents of Cd, As and Hg come from soil geochemistry. (3) The ranking of accumulations of eight heavy metals was IPb>IHg>ICu>INi>IZn>ICr>IAs>ICd, among which Pb was non-moderately polluted and the remaining heavy metals were at the clean level; Nemero comprehensive pollution index showed that As, Cr, Zn, and Ni were mildly polluted, while Pb, Hg, and Cu were moderately polluted. The ranking of potential ecological risk levels for the eight heavy metals was Hg, Pb, Cu, Ni, As, Cd, Cr, Zn. The overall ecological risk level is mild.

scholarly journals Assessment and abatement of the eco-risk caused by mine spoils in the dry subtropical climate

2021 ◽  
Author(s):  
Alexey V. Alekseenko ◽  
Carsten Drebenstedt ◽  
Jaume Bech
Keyword(s):  
Soil Stabilization ◽  
Dust Emission ◽  
Pollution Index ◽  
Risk Level ◽  
Environmental Damage ◽  
Subtropical Climate ◽  
Environmental Threats ◽  
Mine Spoils ◽  
Mine Dumps ◽  
Mine Lands

AbstractThe highly rugged mountainous land topography of the Novorossiysk industrial agglomeration (NW Caucasus, Krasnodar Krai, Russia) and arid climate limit the restoration abilities of disturbed mine lands. Abandoned waste-rock dumps of a marl quarry occupy an area of ca. 150,000 m2 next to the cement plant, residential districts, and a commercial seaport. To assess the eco-risk, topsoil horizons of urban and mine-site Technosols and background Rendzinas were sampled and analyzed; measurements of particulate matter fractions PM1, PM2.5, PM4, and PM10 were conducted throughout the agglomeration. Fugitive dust emission from the unreclaimed marl dumps raises the PM2.5 content in the air by a factor of 2.68 on average. The high sorption capacity of the fine eluvium results in the accumulation of urban emissions by the dust and contributes to the subsequent soil pollution; the Cumulative Pollution Index of pedochemical anomalies reaches the high-risk level over the areas of up to 5 km2. Environmental threats caused by the mine dumps can be assessed more reliably by means of land zoning based on accumulated environmental damage indicators and the debris flow and waterspout risk calculation. To abate the technogenic impact caused by the mine spoils, reclamation actions must be taken including soil stabilization on sensitive sites by application of geosynthetic cover, hydroseeding of the mixture of soil improvers and seeds of herbaceous plants on the slopes, and anti-erosion plantation of cades (Juniperus oxycedrus L.) and smoke trees (Cotinus coggygria Scop.) at subhorizontal surfaces.

scholarly journals Potentially toxic elements pollution in road deposited sediments around the active smelting industry of Korea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hyeryeong Jeong ◽  
Jin Young Choi ◽  
Kongtae Ra
Keyword(s):  
Ecological Risk ◽  
Toxic Elements ◽  
Fine Particles ◽  
Raw Materials ◽  
Pollution Index ◽  
Management Plan ◽  
Potentially Toxic Elements ◽  
Risk Levels ◽  
The Road ◽  
Mean Concentration

AbstractPotentially toxic elements (PTEs) were investigated in the different sizes of road deposited sediments (RDS) around the active smelting industry to understand their sources and to assess the pollution and ecological risk levels. The highest PTEs concentrations was shown near the raw materials import port and the smelting facilities. The fine particles of RDS showed extremely high PTEs concentrations. Zn has the highest mean concentration in the < 63 μm particle size of RDS, followed by Pb > Cu > As > Cr > Ni > Cd > Hg. The PTEs concentrations of this study were the highest values compared to the soils around the smelter and the RDS in urban and industrial areas in the world. This indicates that these PTEs pollution in RDS were mainly attributed to the transportation of raw materials for the smelting industry. According to nemerow pollution index calculation, RDS at all sampling sites with particles of less than 250 mm was seriously polluted with PTEs. The ecological risk was also found to be very high in all RDS fractions and highly toxic elements such as Cd, Pb and Hg pose extremely risk. Given the total amounts PTEs in the road surface, it is necessary to apply RDS removal management plan to reduce the PTEs pollution.

scholarly journals Diurnal and spatial (vertical) dynamics of nutrients (N, P, Si) in four sampling days (summer, fall, winter, and spring) in a tropical shallow reservoir and their relationships with the phytoplankton community

2005 ◽  
Vol 65 (1) ◽  
pp. 141-157 ◽  
Author(s):  
J. J. Ramírez ◽  
C. E. M. Bicudo
Keyword(s):  
Phytoplankton Community ◽  
Southeastern Brazil ◽  
Nitrogen And Phosphorus ◽  
Vertical Variation ◽  
Total N ◽  
Phosphorus Forms ◽  
Reactive Silica ◽  
Photosynthetic Assimilation ◽  
The City ◽  
Total P

The vertical and diurnal variation of nitrogen and phosphorus forms, as well as that of soluble reactive silica (SRS), were studied in four sampling days at Garças reservoir, a shallow tropical one located in the city of São Paulo, in southeastern Brazil. Except for N-NH4, all other inorganic forms of nitrogen (N-NO2, N-NO3, and total N) demonstrated decreased concentrations toward the bottom of reservoir. Similarly, all showed significant diurnal differences on every sampling day, with increased values during the night due to absence of photosynthetic assimilation during that period. In the sampling days, these forms decreased on the spring sampling day due to the bloom of Microcystis registered during this period of the year. All three forms of phosphorus (SRP, particulate P, and total P) showed significant vertical variation, except on the fall sampling day. On the summer sampling day there was an increase of both total P and particulate P, the latter because it constitutes more than 70% of the total P during all sampling days. Hourly phosphorus variation was significant during all sampling days, except for the summer one. The SRS vertical variation was significant during all sampling days, except for that in the spring. It was also different hourly on sampling days.

scholarly journals Research on Anomalous Behavior Detection and Dangerousness Assessment among Civil Aviation Passengers at Checkpoints

2021 ◽  
Author(s):  
Haibin Shen ◽  
yan Zhang
Keyword(s):  
Neural Network ◽  
Index System ◽  
Evaluation Method ◽  
Assessment Method ◽  
Anomalous Behavior ◽  
Civil Aviation ◽  
Risk Level ◽  
Neural Network Method ◽  
Behavior Detection ◽  
Network Method

Abstract Traditional civil aviation security check measures are focused on baggage rather than passengers. The goal of this study is to enhance the level and effectiveness of security measures. We propose an anomalous behavior detection technique for civil aviation passengers and a passenger risk-assessment method based on a neural network method. A large number of real cases were analyzed and summarized to extract indicators of anomalous behavior of civil aviation passengers, and an index system was developed to detect anomalous behavior of passengers at checkpoints. A neural network method was used to evaluate the passengers and classify the risk level to detect potentially dangerous personnel, monitor people, and create an emergency warning system. The synthetic minority oversampling technique (SMOTE), the conjugate gradient method, and a multilayer perceptron neural network were used to classify the risk level of passengers at checkpoints. The results demonstrated that the proposed index system and evaluation method were well suited to deal with the ambiguity and uncertainty in the recognition process. The anomalous behavior of civil aviation passengers at checkpoints and the associated threat level were accurately identified.

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