Heavy Metal Distribution and Sources in Pineapple-Growing Agricultural Soil in Hainan Province, China

An investigation on heavy metal content in agricultural soil growing pineapples was carried out in Hainan Province. The horizontal and vertical distribution of heavy metal in different areas was studied. The sources of heavy metal were conducted using principal component analysis. Generally the study areas were less affected by human activity factors and the overall environmental quality was quite better. The uneven horizontal distribution of heavy metal was controlled mainly by the soil parent material and the vertical distribution of heavy metal was limited by both the role of human activities and the natural effect combined.

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Research on heavy metal level and co-occurrence network in typical ecological fragile area

Journal of Environmental Health Science and Engineering ◽

10.1007/s40201-021-00625-w ◽

2021 ◽

Author(s):

Yiwei Zhao ◽

Liangmin Gao ◽

Fugeng Zha ◽

Xiaoqing Chen ◽

Xiaofang Zhou ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Human Factors ◽

Human Life ◽

Mining Area ◽

Parent Material ◽

Control Value ◽

Pollution Levels ◽

Soil Parent Material ◽

Sampling Points

AbstractDue to the special sensitivity of typical ecologically fragile areas, a series of human life, mining, and other activities have a greater impact on the environment. In this study, three coal mines in Ordos City on the Loess Plateau were selected as the study area, and the pollution levels of heavy metals in the area were studied by measuring As, Hg, Cr, Cd, Cu, Ni, and Pb in the soil of 131 sampling points. Combined with the concept of “co-occurrence network” in biology, the level of heavy metals in soil was studied using geostatistics and remote sensing databases. The results showed that the concentrations of Hg, Cr, Ni, Cu, and Pb in more than half of the sampling points were higher than the local environmental background value, but did not exceed the risk control value specified by China, indicating that human factors have a greater influence, while Cd and As elements are mainly affected Soil parent material and human factors influence. Heavy metal elements have nothing to do with clay and silt but have an obvious correlation with gravel. Cd, Pb, As and Ni, Cd, Cr are all positively correlated, and different heavy metals are in space The distribution also reflects the autocorrelation, mainly concentrated in the northeast of the TS mining area and the middle of the PS mining area.

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The Observation Path Problems and the Formation Conditions of the Elevated Layer of Black Carbon Aerosol

10.20944/preprints202002.0163.v1 ◽

2020 ◽

Author(s):

Lianji Jin ◽

Liang Lin ◽

Deping Ding ◽

Delong Zhao ◽

Bin Zhu ◽

...

Keyword(s):

Vertical Distribution ◽

Black Carbon ◽

Simulation Analysis ◽

Mixing Layer ◽

Horizontal Distribution ◽

Free Atmosphere ◽

Observation Area ◽

Formation Conditions ◽

Black Carbon Aerosol ◽

The Vertical Distribution

Studies on the detection of layers with elevated black carbon aerosol (BC) concentrations and the formation conditions of these layers help understand the vertical distribution of BC concentrations, which will provide a basis for the assessment of climate effects and early BC pollution warnings. By using the Weather Research and Forecasting with Chemistry (WRF-Chem) numerical model, we performed a numerical simulation analysis on the authenticity of strong elevated BC concentration layers that were detected by an aircraft in the mixing layer over Harbin, China, which is a high-emission area, on a clear sunny afternoon in the early heating period of 2016. We then discuss possible problems and solutions when non-vertical paths are used to detect the vertical distribution of BC concentrations. Finally, we discuss the favorable conditions for the formation of elevated BC concentration layers by weak vertical flow. The results show that the horizontal variability of BC concentration in the mixing layer in the observation area in Harbin was sufficiently large during the measurement. This produced a false elevated layer, as detected by the aircraft during one round of spiral flight in the mixing layer. The root mean square of the horizontal distribution of BC concentration did not change with height in the mixing layer during the daytime, but it decreased with the thickness of the mixing layer and was higher in the mixing layer than in the free atmosphere. Therefore, the thinner the mixing layer, in which the vertical distribution of the BC concentration is detected in an inclined path, the stronger interference of the horizontal variability on the detected results. When a spiral flight detection path is used, the aircraft should fly at least two rounds in the mixing layer. In the daytime, due to strong turbulence in the mixing layer, weak vertical uplift is not favorable for the occurrence of elevated BC concentration layers in the mixing layer. In the nighttime, if weak vertical uplift is well matched with the BC concentration or its vertical gradient, elevated BC concentration layers can be formed in the atmosphere. Compared with upper layers far from the ground, nighttime elevated layers are easier to form in lower layers near the ground because high BC concentrations or large vertical gradients are more likely to occur in the lower layers. Both cases facilitate the occurrence of large vertical upward transport rates of BC.

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Analysis and Source Identification of Heavy Metals in Soils of Central Urban Area of Chongqing, China

10.21203/rs.3.rs-856871/v2 ◽

2021 ◽

Author(s):

Wende Chen ◽

Kun Zhu ◽

Yankun Cai ◽

Peihao Peng

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Metal Pollution ◽

Heavy Metal Pollution ◽

Hot Spot ◽

Central City ◽

Principal Component ◽

Parent Material ◽

Soil Heavy Metal ◽

Component Loading

Abstract In megacities, due to frequent human activities, large amounts of metals enter the soil indirectly or directly and eventually flow to people through the food chain. Therefore, the analysis and identification of soil heavy metal sources is an important part of revealing soil heavy metal pollution. The spatial content and potential sources of 11 heavy metals were analyzed from 342 surface soil samples collected from the central city of Chongqing in southwest China. The results showed that the main heavy metal elements under the first principal component loading were copper (Cu), nickel(Ni), zinc (Zn), manganese (Mn), cadmium (Cr), plumbum (Pb) and cadmium (Cd). The second principal component (F2) was mainly loaded with molybdenum (Mo), arsenic (As), mercury (Hg) and antimony (Sb), and the PCA-APCs receptor model of 11 heavy metals was constructed. The PCA-APCs receptor models of 11 heavy metals were constructed. The results of classification regression analysis confirmed the main sources of heavy metals. Population density mainly affected Cu (0.539), soil mainly affected Ni (0.411), Sb (0.493), Zn (0.472) and Mn (0.206), and water quality mainly affected As (0.453) and Mo (0.374). Air quality mainly affects Cd (0.332) and Cr (0.371), traffic activity mainly affects Hg (0.312), and slope mainly affects Pb (0.313). Hot spot analysis showed that heavy metals had a high degree of coincidence with environmental factors such as soil parent material, slope, soil type and traffic activities. The results of this study can be effectively used to make scientific decisions and strategies, and an effective strategy for prevention and control of soil heavy metal pollution should be formulated to protect the urban soil environmental quality.

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The Vertical Distribution of Marine Macroplankton. II. The Pelagic Young of Teleostean Fishes in the Day-time in the Plymouth Area, with a Note on the Eggs of certain Species

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400007165 ◽

1926 ◽

Vol 14 (1) ◽

pp. 101-159 ◽

Cited By ~ 22

Author(s):

F. S. Russell

Keyword(s):

Vertical Distribution ◽

Horizontal Distribution ◽

Seasonal Distribution ◽

Teleostean Fish ◽

Young Fish ◽

Surface Layers ◽

Larval Stages ◽

Different Depths ◽

The Vertical Distribution

1. Horizontal hauls were made with a “stramin” ring-trawl and a silk net at different depths in 1924 and 1925 to determine the vertical distribution of the pelagic post-larval stages of Teleostean fish in daylight. The depths at which the nets fished on every occasion were obtained by means of a graphic depth-recorder.2. It was indicated that there are specific differences in the behaviour of the post-larvae of various fishes as to their vertical distribution in daylight, some preferring the surface layers, others apparently indifferently distributed from surface to bottom, and others preferring the deeper layers and avoiding the surface; of these last it was found that somespecies became abundant at deeper levels than others. A tentative list of distribution types is given on page 107. 3. Eesults emphasise the necessity when examining the horizontal distribution of young fish of sampling all layers : oblique hauls are to be desired fishing at as many levels as possible. 4. Mention is made of seasonal distribution : the year 1924 appeared to differ from 1925 in that certain post-larvae which were prevalent in the plankton well into June or July in the former year were cut short a month earlier in 1925.The post-larvae of Molva molva and of Lophius piscatorius were unusually abundant in 1924 ; post-larval Gobies (Gobiidce) and Wrasses (Labridce) were extremely scarce in 1925 during the months April to beginning of August.

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The Observation Path Problems and the Formation Conditions of the Elevated Layer of Black Carbon Aerosol

Atmosphere ◽

10.3390/atmos11050481 ◽

2020 ◽

Vol 11 (5) ◽

pp. 481

Author(s):

Lianji Jin ◽

Liang Lin ◽

Deping Ding ◽

Delong Zhao ◽

Bin Zhu ◽

...

Keyword(s):

Vertical Distribution ◽

Black Carbon ◽

Simulation Analysis ◽

Mixing Layer ◽

Horizontal Distribution ◽

Free Atmosphere ◽

Observation Area ◽

Formation Conditions ◽

Black Carbon Aerosol ◽

The Vertical Distribution

Studies on the detection of layers with elevated black carbon aerosol (BC) concentrations and the formation conditions of these layers help understand the vertical distribution of BC concentrations, which will provide a basis for the assessment of climate effects and early pollution warnings. By using the Weather Research and Forecasting with Chemistry (WRF-Chem) numerical model, we performed a numerical simulation analysis on the authenticity of strongly elevated BC concentration layers that were detected by an aircraft in the mixing layer over Harbin, China, which is a high-emission area, on a clear sunny afternoon in the early heating period of 2016. We then discuss possible problems and solutions when non-vertical paths are used to detect the vertical distribution of BC concentrations. Finally, we discuss the favorable conditions for the formation of elevated BC concentration layers by a weak vertical flow based on the simulation. The modeling results show that the horizontal variability of BC concentration in the mixing layer in the observation area in Harbin was sufficiently large during the measurement. This produced a false elevated layer, as detected by the aircraft during one round of spiral flight in the mixing layer. The root mean square of the horizontal distribution of BC concentration did not change with height in the mixing layer during the daytime, but it decreased with the thickness of the mixing layer and was higher in the mixing layer than in the free atmosphere. Therefore, the thinner the mixing layer, in which the vertical distribution of the BC concentration is detected in an inclined path, the stronger interference of the horizontal variability on the detected results. In the daytime, due to strong turbulence in the mixing layer, weak vertical uplift is not favorable for the occurrence of elevated BC concentration layers in the mixing layer. In the nighttime, if weak vertical uplift is well-matched with the BC concentration or its vertical gradient, elevated BC concentration layers can be formed in the atmosphere. Compared with upper layers far from the ground, nighttime elevated layers are easier to form in lower layers near the ground because high BC concentrations or large vertical gradients are more likely to occur in the lower layers. Both cases facilitate the occurrence of large vertical upward transport rates of BC.

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Horizontal distribution affects the vertical distribution of native and invasive container‐inhabiting Aedes mosquitoes within an urban landscape

Journal of Vector Ecology ◽

10.1111/jvec.12369 ◽

2020 ◽

Vol 45 (1) ◽

pp. 16-24

Author(s):

Marcelo Schwarz ◽

Brian D. Byrd ◽

Bahjat F. Marayati ◽

Peter W. Blum ◽

Michael B. Wells ◽

...

Keyword(s):

Vertical Distribution ◽

Urban Landscape ◽

Horizontal Distribution ◽

Aedes Mosquitoes ◽

The Vertical Distribution

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PCA Analysis and Concentration of Heavy Metal in the Soil, Guangdong, China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.1952 ◽

2012 ◽

Vol 518-523 ◽

pp. 1952-1955

Author(s):

Chun Lin Yang ◽

Rui Ping Guo ◽

Rong Zeng Liu ◽

Qing Ling Yue ◽

Xiu Juan Ren ◽

...

Keyword(s):

Organic Matter Content ◽

Principal Component ◽

Matter Content ◽

Parent Material ◽

Data Matrix ◽

Geographical Patterns ◽

Analysis Group ◽

Soil Parent Material ◽

Low Concentrations ◽

Local Anomalies

The concentrations of 9 metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in topsoil in Guangdong were investigated based on 260 samples. Principal component analysis (PCA) was applied to the data matrix to evaluate the analytical results and to identify the possible sources of metals. The average concentrations (mg/kg) obtained were: Cu 17.37 mg/kg, Ni 17.7 mg/kg, Cr 56.7 mg/kg, Co 6.83 mg/kg, Mn 223.16 mg/kg, Pb 36.63 mg/kg, Hg 0.10 mg/kg, Cd 0.09 mg/kg and Zn 49.75 mg/kg. The results of factor analysis group Pb, Zn, Cd, Hg and Mn in F1 and Cu, Ni, Cr, Co in F2. The spatial heavy metals component maps show definite association of these factors with the soil parent material and soil types. The concentration levels are relatively low in areas of high pH and low organic matter content concentration. The 9 metals in Guangdong have generally low concentrations and distinct geographical patterns. The local anomalies (found in Cu, Zn and Pb) are attributed to anthropogenic influence.

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