Almost half of the Pb content leaving in the bottom of the sea

Using survey data of Pb in water body from southwest of Jiaozhou Bay to west of bay mouth, in August 1992 and according to the horizontal change model and the vertical change model of matter content put forward by authors, we calculate the horizontal loss amount, vertical diluted amount and vertical sediment amount of Pb in surface and bottom layer and determine the model diagram of Pb content horizontal and vertical changes. The results showed that in August, the absolutely horizontal loss amount of Pb content in surface layer and bottom layer was 8.92μg/L, and the relatively horizontal loss amount of Pb content was 56.10%. The absolutely horizontal increase amount of Pb was 5.74μg/L in bottom layer, and the relatively horizontal increase amount was 42.23%. In the southwestern waters of the bay, the absolutely vertical diluted amount of Pb was 8.05μg/L in both surface and bottom layer, and the relatively vertical diluted amount was 50.62%. Meanwhile, in the western waters of bay mouth, Pb content in the surface and bottom layer had an absolutely vertical sediment amount of 6.61μg/L and a relatively vertical sediment amount of 48.63%. From the southwestern waters of the bay to the western waters of the bay mouth, a large amount of Pb content in the surface layer is deposited on the seabed. Therefore, during the horizontal migration of Pb content on the surface, the loss was nearly 60.00% when the current left the bay. However, Pb content in the bottom layer increased by 42.23% during its horizontal migration. Thus, the high Pb content in the surface layer is retained at the bottom of Jiaozhou Bay. When the current left the inside of the bay, Pb content in the surface layer was relatively high with the vertical diluted amount of Pb content in the surface layer and bottom layer reaching almost 50%. When the main sea current reached the western part of the bay mouth, the Pb content in the surface layer could settle on the seabed rapidly and continuously with a high sediment amount of 48.63%.

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Cd Content with an Always High Vertical Diluted Amount

E3S Web of Conferences ◽

10.1051/e3sconf/202019801009 ◽

2020 ◽

Vol 198 ◽

pp. 01009

Author(s):

Dongfang Yang ◽

Xinmin Huang ◽

Tao Jiang ◽

Linzhen Wei ◽

Shengjun Zhang

Keyword(s):

Surface Layer ◽

Block Diagram ◽

Jiaozhou Bay ◽

Bottom Layer ◽

Matter Content ◽

Change Model ◽

The West ◽

Horizontal Migration ◽

Sea Current ◽

Vertical Changes

Based on the investigation data about Cd in Jiaozhou Bay in August 1992 and the horizontal change model of matter content and the vertical change model of matter content proposed by the authors, the horizontal loss amount, vertical diluted amount and vertical sediment amount of Cd content in the surface and bottom layers from the southeast waters of the bay to the west waters of the bay mouth were calculated, and the model block diagram of the horizontal and vertical changes of Cd content was determined. The results show that in August, the absolutely loss amount of Cd content in the surface layer was 0.09μg/L, and the absolutely increase amount of Cd content in the bottom layer was 0.10μg/L. The relatively loss amount of Cd content in the surface layer was 12.00%, and the relatively increase amount of Cd content in the bottom layer was 41.66%. Cd content in the surface and bottom layershadabsolutely vertical diluted amount of 0.42-0.61μg/L, and its relatively vertical diluted amount was 63.63-81.33%. In August, in the horizontal migration of Cd content in the surface and bottom layers, the main sea current carried high Cd content in the surface waters.And after passing through the nearshore waters of the bay, one tenth of the Cd content in the surface layer settled to the seabed. In the horizontal migration process of Cd content in the surface layer, the loss amount of Cd content in the surface layer reached 12.00% in the nearshore waters around Jiaozhou Bay, thus the increase amount of Cd content in the bottom layer reached 41.66%. It reveals that the high Cd content in the surface layer could rapidly and continuously sink to the seabed, and the Cd content in the seabed waters in Jiaozhou Bay increased by 41.66%. In August, in the process of vertical migration, the Cd content transported by main sea current was relatively high, and the vertical diluted amount of Cd content in the surface and bottom layers was high 63.63 - 81.33% from the southeast waters of the bay to the waters in the west of the bay mouth.

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Calculation of Cd Content Settlement in a Circle of Coastal Waters

E3S Web of Conferences ◽

10.1051/e3sconf/202019801020 ◽

2020 ◽

Vol 198 ◽

pp. 01020

Author(s):

Dongfang Yang ◽

Haixia Li ◽

Longlei Zhang ◽

Qi Wang ◽

Hong Zhu

Keyword(s):

Surface Layer ◽

Surface Waters ◽

Jiaozhou Bay ◽

Bottom Layer ◽

Water Area ◽

Matter Content ◽

Horizontal Migration ◽

Sea Current ◽

Migration Law ◽

Very High

With the help of the data about Cd in the southeast and southwest waters of Jiaozhou bay and models of horizontal and vertical matter content variation proposed by the authors, horizontal loss amount and vertical diluted amount of Cd content in the surface layer and bottom layer are calculated, and the model block diagrams of horizontal and vertical variation of Cd content are determined. The calculation shows that in August, the absolutely horizontal loss amount of Cd content in the surface layer and bottom layer was 0.06-0.43μg/L, and the relatively horizontal loss amount of Cd content in the surface layer and bottom layer was 42.85-57.33%. In the southeast and southwest waters of the bay, the absolutely verticaldiluted amount of Cd content in the surface layer and bottom layer was 0.24-0.61μg/L, and the relatively vertical diluted amount was 75.00-81.33%. In the process of horizontal migration in August, in the surface waters, the main sea current carried Cd content through a circle of the nearshore waters in the bay, and there was almost no source of Cd content. Therefore, in the horizontal migration process of Cd content, after a long journey, the Cd content in the surface layer and bottom layer got a lot of losses. Specifically, the absolutely horizontal loss amount was 0.06- 0.43μg/L, and the relatively horizontal loss amount was 42.85-57.33%, which proved Dongfang Yang’s migration law of matter content put forward by the authors. In the process of vertical migration in August, the Cd content transported by the main sea current was higher in the southeast waters of the bay, and the vertical diluted amount of Cd content in the surface layer and bottom layer was 81.33%. The main sea current reached the waters of the southwest bay from the waters of the southeast bay through a circle of the nearshore waters in the bay. At this time, the Cd content transported by the main sea current was relatively low in the waters of the southwest bay, but the vertical diluted amount of Cd content in the surface layer and bottom layer was still very high, which was 75.00%. It reveals that the vertical diluted amount of Cd content in the surface layer and bottom layer was very high in any water area, whether the Cd content is high or low.

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The influence of the Pb Content of Source Transport on its Distribution in the Bottom Layer

E3S Web of Conferences ◽

10.1051/e3sconf/202018502017 ◽

2020 ◽

Vol 185 ◽

pp. 02017

Author(s):

Dongfang Yang ◽

Dong Yang ◽

Weifeng Ling ◽

Dong Lin ◽

Haixia Li

Keyword(s):

Water Quality ◽

Surface Layer ◽

Water Body ◽

Jiaozhou Bay ◽

Bottom Layer ◽

Horizontal Distribution ◽

Ocean Current ◽

Open Sea ◽

Sea Current ◽

Bottom Waters

Based on the survey data of Jiaozhou Bay in 1992, the vertical distribution and seasonal variation of Pb in the surface and bottom waters from the bay center to the south of the bay mouth were studied, and the seasonal distribution, range and horizontal distribution trend of Pb content in the surface and bottom waters were determined. The results show that in May, August and October, Pb content in the waters from the south of the bay mouth to the center of the bay, and in the whole water body from the surface to the bottom, ranged from 4.20 to 24.39 μg/L, which met the national sea water quality standard of class II, class III and class IV. In other words, water quality was mildly, moderately and severely polluted by Pb. In the surface and bottom water, the Pb content was from low to high in May, October and August; In addition, the seasonal change of Pb content in the water body from low to high was as follows: spring, autumn and summer. In May, August and October, when the content of Pb in the surface layer was high, the corresponding bottom layer was high. And when the content of Pb in the surface layer was relatively high, and the corresponding bottom layer was relatively high. It shows that in May, August and October, the loss of Pb content from the surface layer to the bottom layer was relatively large. Further, in the waters from the southeast to the center, in May and August, the horizontal distribution trend of Pb in the surface layer was opposite to that in the bottom layer. But in October, the horizontal distribution trend of Pb in the surface layer was consistent with that in the bottom layer. What’s more, from May to October, the seasonal variation of Pb content in the bottom layer of the water body in the southeastern Jiaozhou Bay was mainly decided by that of Pb content transported by the open ocean current. In the water body in the center of Jiaozhou Bay, the seasonal change of Pb content in the bottom layer was different from that in the surface layer and from that in the ocean current. In terms of time scale, in the waters from the southern bay mouth to the center of the bay, in May, August and October, the Pb content in the surface and the bottom layer changed in the same range, maintaining the consistency. Furthermore, in terms of spatial scale, in May and August, according to the high content and increasing trend of Pb transported by the open sea current, the horizontal distribution trend of Pb in the surface layer was opposite to that in the bottom layer. Nonetheless, in October, the Pb content transported by the open sea current was relatively low and showed a trend of decrease. And the horizontal distribution of Pb in the surface layer was consistent with that in the bottom layer.

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Large amount of settlement brought by the river

E3S Web of Conferences ◽

10.1051/e3sconf/202125203014 ◽

2021 ◽

Vol 252 ◽

pp. 03014

Author(s):

Dongfang Yang ◽

Haixia Li ◽

Qi Wang ◽

Hong Zhu ◽

Weifeng Ling

Keyword(s):

Surface Layer ◽

Surface Waters ◽

Bottom Layer ◽

Matter Content ◽

Southeastern Part ◽

Change Models ◽

Sea Current ◽

Before And After ◽

Vertical Changes ◽

Set Up

Utilizing the survey dataset of Pb in waters from south of bay mouth to southeast of bay in October 1992, and applying the horizontal and vertical change models of matter content put forward by authors, we would calculate the horizontal loss amount, vertical diluted amount and vertical sediment amount of Pb in surface and bottom layers and set up the model diagram on the Pb content horizontal and vertical changes. The research results unveiled that in October, the absolutely horizontal loss amount of Pb content in surface layer and bottom layer was 3.58–7.89μg/L, and the relatively horizontal loss amount of Pb content in surface layer and bottom layer was 27.01–51.30%. In the southern waters of bay mouth, the absolutely vertical sediment amount of Pb was 2.13μg/L, and the relatively vertical sediment amount was 13.84%. In the southeastern waters of the bay, Pb content in the surface layer and bottom layer had an absolutely vertical diluted amount of 6.61μg/L and a relatively vertical diluted amount of 22.54%. In October, in the surface waters, after the main sea current brought high Pb content to the southern waters of the bay mouth, the Pb content began to settle to the seabed in large quantities, leading to a horizontal loss amount of almost one third 27.01% of the Pb content on surface when the current entered the bay. Pb content in the bottom layer of the seabed also reduced greatly by 51.30%, which was more than half. It revealed that Pb content in the surface layer could settle to the bottom rapidly and continuously when the current entered the bay, causing a large loss amount of Pb content in the surface layer. At the same time, the Pb content on the bottom was largely buried in the seabed, causing a lot of losses. In October, in the process of vertical migration, the vertical sediment amount of Pb in the surface and bottom layers 13.84% was shifted to the vertical diluted amount of Pb in the surface and bottom layers 22.54% before and after the main sea current entered the bay. The high Pb content transported by the main sea current had a large amount of settlement in the southern waters of the bay mouth and accumulated in the seabed. However, when the current reached the bay with Pb content, there was also a large amount of settlement in the southeastern part of the bay, but no accumulation in the seabed.

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Transfer Mechanism and Change Process of Matter Content in Jiaozhou Bay

E3S Web of Conferences ◽

10.1051/e3sconf/202124502030 ◽

2021 ◽

Vol 245 ◽

pp. 02030

Author(s):

Dongfang Yang ◽

Haixia Li ◽

Dong Lin ◽

Weifeng Ling ◽

Hong Zhu

Keyword(s):

Surface Water ◽

Change Process ◽

Bottom Water ◽

Jiaozhou Bay ◽

Matter Content ◽

Transfer Mechanism ◽

Ocean Current ◽

Deep Channel ◽

Sea Current ◽

Bottom Waters

Based on the survey data of Jiaozhou Bay in 1992, the changes of Pb content in the surface and bottom waters affected by the ocean current in the process of transportation in Jiaozhou Bay were studied, and the sedimentation process and mechanism of Pb content in the surface and bottom waters were determined. The time change process of sedimentation shows that: from May to October, 1) the Pb content transported by the ocean current from the main sea decided the Pb content change in the bottom water; 2) in August, under the carrying of a large number of plankton and suspended particulate matter, the Pb content transported by the ocean current and that in the surface and bottom water reached the maximum value in a year. According to the spatial change process of subsidence, the results show that in August and October, the inlet of the “Cangkou Channel”, the outlet of the “Former Reef Channel” and the deep channel of the strait on the side of Xuejia Island all revealed narrower channel, accelerated current, and deep erosion, forming a deep channel. In such waters, a large amount of Pb content was deposited. On the basis of the sedimentation process in the center of the bay, the outer sea current carried a high content of Pb to surround the nearshore waters in the bay. In May, the main sea current did not affect the surface water in the center of Jiaozhou Bay, nor did it affect the bottom water in the center of Jiaozhou Bay. From May to October, the ocean current didn’t affect the surface water in the center of Jiaozhou Bay, either, but it has brought a huge impact on the bottom water in the center of Jiaozhou Bay. In the transfer process of Pb content in the water body in the center of the bay, the authors put forward the transfer mechanism of the matter content in Jiaozhou Bay, and establish the block diagram of the modelwhich demonstrates the mechanism and the change process of the matter content transfer.

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Principle and Model Block Diagrams of Cd Content Monthly Variation in Surface and Bottom Waters in Central Bay

E3S Web of Conferences ◽

10.1051/e3sconf/202123603019 ◽

2021 ◽

Vol 236 ◽

pp. 03019

Author(s):

Dongfang Yang ◽

Dong Yang ◽

Weifeng Ling ◽

Dong Lin ◽

Haixia Li

Keyword(s):

Surface Water ◽

Water Body ◽

Bottom Water ◽

Jiaozhou Bay ◽

Variation Principle ◽

Monthly Variation ◽

Model Block ◽

Sea Current ◽

Bottom Waters ◽

Monthly Changes

According to survey data, in Jiaozhou Bay in 1992, the vertical distribution of Cd content and monthly changes in the surface and the bottom of the central sea area of Jiaozhou Bay were studied, and monthly changes, migration processes and variational principles of the Cd content in surface and bottom water were determined. In May, August, and October, the water body that the main sea current did not pass through were those in the center of the bay. Cd content in central surface water of Jiaozhou Bay was not transported from any source outside the bay from May to October. The results showed that Cd content transported by the main sea current changed from low to high in October, May and August; Cd content transported by the bay current changed from low to high: October, August and May; Cd content in surface water in the bay center changed from low to high in: August, May and October; Cd content in the bottom bay center changed from low to high in May, October and August. Thus, from May to October, monthly changes in these four parts were different. For this reason, the monthly variation principle of Cd content in the surface and bottom waters of the bay was proposed. In addition, the model block diagrams were established to show the change process and principle of Cd content deposition and migration. The principle shows that the bay current has no direct effect on the surface water in the center of the bay from May to October. However, the bottom water body in the center of Jiaozhou Bay was greatly affected, and the surface water body in the center of Jiaozhou Bay was further affected by the upwelling.

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Nitric oxide (NO) in the Bohai Sea and the Yellow Sea

Biogeosciences ◽

10.5194/bg-16-4485-2019 ◽

2019 ◽

Vol 16 (22) ◽

pp. 4485-4496 ◽

Cited By ~ 1

Author(s):

Ye Tian ◽

Chao Xue ◽

Chun-Ying Liu ◽

Gui-Peng Yang ◽

Pei-Feng Li ◽

...

Keyword(s):

Nitric Oxide ◽

Surface Layer ◽

Yellow Sea ◽

Bohai Sea ◽

Limit Of Detection ◽

Bottom Layer ◽

The Yellow Sea ◽

The Bohai Sea ◽

Significant Difference ◽

Average Flux

Abstract. Nitric oxide (NO) is a short-lived compound of the marine nitrogen cycle; however, our knowledge about its oceanic distribution and turnover is rudimentary. Here we present the measurements of dissolved NO in the surface and bottom layers at 75 stations in the Bohai Sea (BS) and the Yellow Sea (YS) in June 2011. Moreover, NO photoproduction rates were determined at 27 stations in both seas. The NO concentrations in the surface and bottom layers were highly variable and ranged from below the limit of detection (i.e., 32 pmol L−1) to 616 pmol L−1 in the surface layer and 482 pmol L−1 in the bottom layer. There was no significant difference (p>0.05) between the mean NO concentrations in the surface (186±108 pmol L−1) and bottom (174±123 pmol L−1) layers. A decreasing trend of NO in bottom-layer concentrations with salinity indicates a NO input by submarine groundwater discharge. NO in the surface layer was supersaturated at all stations during both day and night and therefore the BS and YS were a persistent source of NO to the atmosphere at the time of our measurements. The average flux was about 4.5×10-16 mol cm−2 s−1 and the flux showed significant positive relationship with the wind speed. The accumulation of NO during daytime was a result of photochemical production, and photoproduction rates were correlated to illuminance. The persistent nighttime NO supersaturation pointed to an unidentified NO dark production. NO sea-to-air flux densities were much lower than the NO photoproduction rates. Therefore, we conclude that the bulk of the NO produced in the mixed layer was rapidly consumed before its release to the atmosphere.

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NUTRIENT PHOSPHATE, NITRATE AND SILICATE DISTRIBUTION OF NATUNA ARCHIPELAGO WATERS

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.28930/jitkt.v4i2.7792 ◽

2012 ◽

Vol 4 (2) ◽

Author(s):

Muswerry Muchtar

Keyword(s):

Surface Layer ◽

Bottom Layer ◽

Phosphate Concentration ◽

Silicate Concentration ◽

Marine Life ◽

Phosphate Nitrate ◽

Standard Quality

<p>Research on phosphate, nitrate and silicate distributions of Natuna ArchipelagoWaters was conducted using RV Baruna Jaya VIII in April 2011. Concentration of phosphate, nitrate and silicate were analyses by Spectrophotometry. The purpose of the study was to assess the distribution of nutrients as fertility indicator of marine life. The results showed that the phosphate concentration at surface layer of Subi, Bunguran, and Laut islands ranged from 0,04 to 0,22 µg A/l, 0,04 to 0,18 µg A/l and from 0,04 to 0,13 µg A/l, with average 0,11 µgA/l, 0,08 µgA/l and 0,07 µg A/l, respectivelly. Concentration of nitrate ranged from 0,31 to 4,90 µg A/l, 0,23 to 2,29 µg A/l and from 0,14 to 0,32 µg A/l with average of 90 µgA/l, 0,78 µg A/l and 0,22 µg A/l, respectivelly. Silicate concentration ranged from 2,97 to 5,35 µg A/l, 2,28 to 4,85 µg A/l and from 2,28 to 3,57 µg A/l with average 4,49 µgA/l, 3,62 µg A/l and 3,02 µg A/l,respectivelly. While phosphate concentration at bottom layer of Subi, Bunguran and Laut islands ranged from 0,04-0,27 µg A/l, 0,04-0,31 µg A/l and 0,09-0,22µg A/l,, with average 0,13 µgA/l, 0,13 µgA/l dan 0,12, µg A/l respectivelly. Concentration of nitrate ranged from 2,59-5,61µg A/l, 0,73-4,75 µg A/l and 2,06-3,03 µg A/l with average 2,85 µgA/l, 3,14 µg A/l and 2,49 µg A/ respectivelly. Silicate concentration in Subi, Bunguran and Laut Islands ranged from 4,46-6,21 µg A/l, 3,20-5,84 µg A/l dan 3,07-4,66 µg A/l with average 5,323,73 µgA/l, 4,74 µg A/l dan 3,73 µg A/l. In general concentration of those nutrient of Natuna Archipelago waters was still within the Standard Quality set by the Ministery of Environment (KMNLH).</p> <p>Keywords: nutrient, phosphate, nitrate, silicate, Natuna Archipelago waters.</p>

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PHOSPHORUS FORMS AND ADSORPTION IN A TYPIC QUARTZIPSAMMENT CULTIVATED WITH SUGARCANE HARVESTED WITHOUT BURNING

Revista Caatinga ◽

10.1590/1983-21252017v30n209rc ◽

2017 ◽

Vol 30 (2) ◽

pp. 343-352 ◽

Cited By ~ 1

Author(s):

JOSÉ DE SOUZA OLIVEIRA FILHO ◽

MARCOS GERVASIO PEREIRA ◽

BOANERGES FREIRE DE AQUINO ◽

THALES VINÍCIUS DE ARAÚJO VIANA

Keyword(s):

Organic Matter Content ◽

Soil Surface ◽

Bottom Layer ◽

Phosphate Fertilizer ◽

P Uptake ◽

Cane Sugar ◽

Matter Content ◽

Maximum Adsorption Capacity ◽

Native Forest ◽

P Adsorption

ABSTRACT The objective of this study was to evaluate the adsorption of phosphorus (P) and changes in the concentrations of organic and inorganic forms of P in a Neossolo Quartzarênico (Typic Quartzipsamment) after 9 years of successive cultivation with sugar cane without burning to harvest. Therefore, two areas, one in which cane sugar was planted and a native forest reference area, located in the municipality of Paraipaba-CE, were selected. In each area, samples were collected at depths of 0−0.025, 0.025−0.05, 0.05−0.10, 0.10−0.20, and 0.20−0.30 m, and the levels of organic (Po) and inorganic (Pi) phosphorus obtained by sequential extraction, the remaining phosphorus, and the maximum adsorption capacity of phosphorus by the soil were determined. In general, the permanence of straw on the soil surface under sugarcane cultivation promoted the maintenance of Po levels in the surface layers of the profile. The Po accumulated predominantly in the Po fraction extracted with sodium bicarbonate in both areas. Regarding the Pi content, changes were more evident during cultivation due to the effect of successive phosphate fertilizer applications. The fraction extracted with 0.1 mol L -1 sodium hydroxide was the most representative, with the highest levels of P uptake. P adsorption was influenced by the initial content of the nutrient in the soil and no relationship between P adsorption and organic matter content was observed. The highest level of adsorption was observed in the bottom layer of the forest area (133.3 mg kg -1) and the lowest level of adsorption was observed on the surface layer of the area under sugarcane cultivation (59.5 kg mg-1).

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