Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes

He Yuhong; Zhou Qilin

doi:doi:10.11648/j.ajwse.20210702.12

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Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes

He Yuhong, Zhou Qilin

Published in American Journal of Water Science and Engineering (Volume 7, Issue 2)

Received: 20 April 2021 Accepted: 7 May 2021 Published: 14 May 2021

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Abstract

The high organic loading sediment in the areas of algal accumulation are the primary cause of frequent occurrence of black water in the western Chao Lake. Through an algal accumulation experiment, plow-tillage based on resuspension characteristics and its effect on lake sediment was assessed using a large device capable of simulating lake-winds and sediment resuspension. The dynamics of overlying water coloration, ρ(Fe²⁺), ρ(S2-) in the process of black water induction, the key physicochemical characteristics of newly formed water–sediment interface, and iron and sulfur variations in interstitial-water and their response to plow-tillage were examined. The results showed that plow-tillage depth significantly influenced black-water formation; a 15 cm plow-tillage depth helped in controlling black-water. When black water occurred in other plow-tillage controls, i.e., (2, 5, and 10 cm), along with blank-treatments during day 8 to 14, typical overlying water characteristics [ρ(Fe²⁺) and ρ(S2-)] of the plow-tillage 15 cm treatments were 68.6%, 79.5%, 48.1%, 46.7%, and 51.3%; and 75.2%, 65.7%, 57.1%, 74.5%, and 75.0%, respectively, in comparison to that of the other plow-tillage controls and blank-treatments. Further analysis of the bottom-water and bottom-sediments revealed that the 15 cm plow-tillage depth treatment significantly enhanced the tolerance of the fresh water–sediment interface to algal accumulation and anoxic environments. Through the black water induction simulation, the dissolved oxygen concentration, redox potential, and pH of the bottom-water and at the interface were observably much higher than those in the black-water groups. However, ρ(ΣH₂S) was significantly lower than that of other treatments. The ρ(Fe²⁺) in the surface-sediment water was 0.54 mg/L, which corresponds only 25.3–33.7% that of the black-water groups. Fe²⁺ accounted for 25.2% of the total iron, being considerably lower than ~40.0% of the black-water groups. The concentration of acid-volatile sulfides was 0.51 µg/g, which corresponds only 14.6–17.2% that of the black-water groups. Overall, plow-tillage helped to physically improve sediment in areas of algal accumulation. Plow-tillage could help turn surface-sediment overloaded with organic pollutants to the lower-layer, blocking material migration and supply of contaminated surface-sediment, and controlling anaerobic microbial activity. It could prevent the formation of black water-generating substances in the water column where algae accumulate and die, effectively preventing the occurrence of black water.

Published in	American Journal of Water Science and Engineering (Volume 7, Issue 2)
DOI	10.11648/j.ajwse.20210702.12
Page(s)	39-47
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2021. Published by Science Publishing Group

Keywords

Plow-tillage, Shallow-lake, Algal Accumulation, Black-water Events

References

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He Yuhong, Zhou Qilin. (2021). Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. American Journal of Water Science and Engineering, 7(2), 39-47. https://doi.org/10.11648/j.ajwse.20210702.12

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ACS Style

He Yuhong; Zhou Qilin. Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. Am. J. Water Sci. Eng. 2021, 7(2), 39-47. doi: 10.11648/j.ajwse.20210702.12

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AMA Style

He Yuhong, Zhou Qilin. Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. Am J Water Sci Eng. 2021;7(2):39-47. doi: 10.11648/j.ajwse.20210702.12

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@article{10.11648/j.ajwse.20210702.12,
  author = {He Yuhong and Zhou Qilin},
  title = {Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes},
  journal = {American Journal of Water Science and Engineering},
  volume = {7},
  number = {2},
  pages = {39-47},
  doi = {10.11648/j.ajwse.20210702.12},
  url = {https://doi.org/10.11648/j.ajwse.20210702.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajwse.20210702.12},
  abstract = {The high organic loading sediment in the areas of algal accumulation are the primary cause of frequent occurrence of black water in the western Chao Lake. Through an algal accumulation experiment, plow-tillage based on resuspension characteristics and its effect on lake sediment was assessed using a large device capable of simulating lake-winds and sediment resuspension. The dynamics of overlying water coloration, ρ(Fe2+), ρ(S2-) in the process of black water induction, the key physicochemical characteristics of newly formed water–sediment interface, and iron and sulfur variations in interstitial-water and their response to plow-tillage were examined. The results showed that plow-tillage depth significantly influenced black-water formation; a 15 cm plow-tillage depth helped in controlling black-water. When black water occurred in other plow-tillage controls, i.e., (2, 5, and 10 cm), along with blank-treatments during day 8 to 14, typical overlying water characteristics [ρ(Fe2+) and ρ(S2-)] of the plow-tillage 15 cm treatments were 68.6%, 79.5%, 48.1%, 46.7%, and 51.3%; and 75.2%, 65.7%, 57.1%, 74.5%, and 75.0%, respectively, in comparison to that of the other plow-tillage controls and blank-treatments. Further analysis of the bottom-water and bottom-sediments revealed that the 15 cm plow-tillage depth treatment significantly enhanced the tolerance of the fresh water–sediment interface to algal accumulation and anoxic environments. Through the black water induction simulation, the dissolved oxygen concentration, redox potential, and pH of the bottom-water and at the interface were observably much higher than those in the black-water groups. However, ρ(ΣH2S) was significantly lower than that of other treatments. The ρ(Fe2+) in the surface-sediment water was 0.54 mg/L, which corresponds only 25.3–33.7% that of the black-water groups. Fe2+ accounted for 25.2% of the total iron, being considerably lower than ~40.0% of the black-water groups. The concentration of acid-volatile sulfides was 0.51 µg/g, which corresponds only 14.6–17.2% that of the black-water groups. Overall, plow-tillage helped to physically improve sediment in areas of algal accumulation. Plow-tillage could help turn surface-sediment overloaded with organic pollutants to the lower-layer, blocking material migration and supply of contaminated surface-sediment, and controlling anaerobic microbial activity. It could prevent the formation of black water-generating substances in the water column where algae accumulate and die, effectively preventing the occurrence of black water.},
 year = {2021}
}

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TY  - JOUR
T1  - Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes
AU  - He Yuhong
AU  - Zhou Qilin
Y1  - 2021/05/14
PY  - 2021
N1  - https://doi.org/10.11648/j.ajwse.20210702.12
DO  - 10.11648/j.ajwse.20210702.12
T2  - American Journal of Water Science and Engineering
JF  - American Journal of Water Science and Engineering
JO  - American Journal of Water Science and Engineering
SP  - 39
EP  - 47
PB  - Science Publishing Group
SN  - 2575-1875
UR  - https://doi.org/10.11648/j.ajwse.20210702.12
AB  - The high organic loading sediment in the areas of algal accumulation are the primary cause of frequent occurrence of black water in the western Chao Lake. Through an algal accumulation experiment, plow-tillage based on resuspension characteristics and its effect on lake sediment was assessed using a large device capable of simulating lake-winds and sediment resuspension. The dynamics of overlying water coloration, ρ(Fe2+), ρ(S2-) in the process of black water induction, the key physicochemical characteristics of newly formed water–sediment interface, and iron and sulfur variations in interstitial-water and their response to plow-tillage were examined. The results showed that plow-tillage depth significantly influenced black-water formation; a 15 cm plow-tillage depth helped in controlling black-water. When black water occurred in other plow-tillage controls, i.e., (2, 5, and 10 cm), along with blank-treatments during day 8 to 14, typical overlying water characteristics [ρ(Fe2+) and ρ(S2-)] of the plow-tillage 15 cm treatments were 68.6%, 79.5%, 48.1%, 46.7%, and 51.3%; and 75.2%, 65.7%, 57.1%, 74.5%, and 75.0%, respectively, in comparison to that of the other plow-tillage controls and blank-treatments. Further analysis of the bottom-water and bottom-sediments revealed that the 15 cm plow-tillage depth treatment significantly enhanced the tolerance of the fresh water–sediment interface to algal accumulation and anoxic environments. Through the black water induction simulation, the dissolved oxygen concentration, redox potential, and pH of the bottom-water and at the interface were observably much higher than those in the black-water groups. However, ρ(ΣH2S) was significantly lower than that of other treatments. The ρ(Fe2+) in the surface-sediment water was 0.54 mg/L, which corresponds only 25.3–33.7% that of the black-water groups. Fe2+ accounted for 25.2% of the total iron, being considerably lower than ~40.0% of the black-water groups. The concentration of acid-volatile sulfides was 0.51 µg/g, which corresponds only 14.6–17.2% that of the black-water groups. Overall, plow-tillage helped to physically improve sediment in areas of algal accumulation. Plow-tillage could help turn surface-sediment overloaded with organic pollutants to the lower-layer, blocking material migration and supply of contaminated surface-sediment, and controlling anaerobic microbial activity. It could prevent the formation of black water-generating substances in the water column where algae accumulate and die, effectively preventing the occurrence of black water.
VL  - 7
IS  - 2
ER  -

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Author Information

He Yuhong

Huatian Engineering & Technology Corporation, Metallurgical Corporation of China Ltd, Nanjing, China
Zhou Qilin

Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing, China

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He Yuhong, Zhou Qilin. (2021). Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. American Journal of Water Science and Engineering, 7(2), 39-47. https://doi.org/10.11648/j.ajwse.20210702.12

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ACS Style

He Yuhong; Zhou Qilin. Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. Am. J. Water Sci. Eng. 2021, 7(2), 39-47. doi: 10.11648/j.ajwse.20210702.12

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AMA Style

He Yuhong, Zhou Qilin. Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes. Am J Water Sci Eng. 2021;7(2):39-47. doi: 10.11648/j.ajwse.20210702.12

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@article{10.11648/j.ajwse.20210702.12,
  author = {He Yuhong and Zhou Qilin},
  title = {Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes},
  journal = {American Journal of Water Science and Engineering},
  volume = {7},
  number = {2},
  pages = {39-47},
  doi = {10.11648/j.ajwse.20210702.12},
  url = {https://doi.org/10.11648/j.ajwse.20210702.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajwse.20210702.12},
  abstract = {The high organic loading sediment in the areas of algal accumulation are the primary cause of frequent occurrence of black water in the western Chao Lake. Through an algal accumulation experiment, plow-tillage based on resuspension characteristics and its effect on lake sediment was assessed using a large device capable of simulating lake-winds and sediment resuspension. The dynamics of overlying water coloration, ρ(Fe2+), ρ(S2-) in the process of black water induction, the key physicochemical characteristics of newly formed water–sediment interface, and iron and sulfur variations in interstitial-water and their response to plow-tillage were examined. The results showed that plow-tillage depth significantly influenced black-water formation; a 15 cm plow-tillage depth helped in controlling black-water. When black water occurred in other plow-tillage controls, i.e., (2, 5, and 10 cm), along with blank-treatments during day 8 to 14, typical overlying water characteristics [ρ(Fe2+) and ρ(S2-)] of the plow-tillage 15 cm treatments were 68.6%, 79.5%, 48.1%, 46.7%, and 51.3%; and 75.2%, 65.7%, 57.1%, 74.5%, and 75.0%, respectively, in comparison to that of the other plow-tillage controls and blank-treatments. Further analysis of the bottom-water and bottom-sediments revealed that the 15 cm plow-tillage depth treatment significantly enhanced the tolerance of the fresh water–sediment interface to algal accumulation and anoxic environments. Through the black water induction simulation, the dissolved oxygen concentration, redox potential, and pH of the bottom-water and at the interface were observably much higher than those in the black-water groups. However, ρ(ΣH2S) was significantly lower than that of other treatments. The ρ(Fe2+) in the surface-sediment water was 0.54 mg/L, which corresponds only 25.3–33.7% that of the black-water groups. Fe2+ accounted for 25.2% of the total iron, being considerably lower than ~40.0% of the black-water groups. The concentration of acid-volatile sulfides was 0.51 µg/g, which corresponds only 14.6–17.2% that of the black-water groups. Overall, plow-tillage helped to physically improve sediment in areas of algal accumulation. Plow-tillage could help turn surface-sediment overloaded with organic pollutants to the lower-layer, blocking material migration and supply of contaminated surface-sediment, and controlling anaerobic microbial activity. It could prevent the formation of black water-generating substances in the water column where algae accumulate and die, effectively preventing the occurrence of black water.},
 year = {2021}
}

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TY  - JOUR
T1  - Effects of Plow-Tillage on Preventing and Controlling the Black Water Events in Shallow Lakes
AU  - He Yuhong
AU  - Zhou Qilin
Y1  - 2021/05/14
PY  - 2021
N1  - https://doi.org/10.11648/j.ajwse.20210702.12
DO  - 10.11648/j.ajwse.20210702.12
T2  - American Journal of Water Science and Engineering
JF  - American Journal of Water Science and Engineering
JO  - American Journal of Water Science and Engineering
SP  - 39
EP  - 47
PB  - Science Publishing Group
SN  - 2575-1875
UR  - https://doi.org/10.11648/j.ajwse.20210702.12
AB  - The high organic loading sediment in the areas of algal accumulation are the primary cause of frequent occurrence of black water in the western Chao Lake. Through an algal accumulation experiment, plow-tillage based on resuspension characteristics and its effect on lake sediment was assessed using a large device capable of simulating lake-winds and sediment resuspension. The dynamics of overlying water coloration, ρ(Fe2+), ρ(S2-) in the process of black water induction, the key physicochemical characteristics of newly formed water–sediment interface, and iron and sulfur variations in interstitial-water and their response to plow-tillage were examined. The results showed that plow-tillage depth significantly influenced black-water formation; a 15 cm plow-tillage depth helped in controlling black-water. When black water occurred in other plow-tillage controls, i.e., (2, 5, and 10 cm), along with blank-treatments during day 8 to 14, typical overlying water characteristics [ρ(Fe2+) and ρ(S2-)] of the plow-tillage 15 cm treatments were 68.6%, 79.5%, 48.1%, 46.7%, and 51.3%; and 75.2%, 65.7%, 57.1%, 74.5%, and 75.0%, respectively, in comparison to that of the other plow-tillage controls and blank-treatments. Further analysis of the bottom-water and bottom-sediments revealed that the 15 cm plow-tillage depth treatment significantly enhanced the tolerance of the fresh water–sediment interface to algal accumulation and anoxic environments. Through the black water induction simulation, the dissolved oxygen concentration, redox potential, and pH of the bottom-water and at the interface were observably much higher than those in the black-water groups. However, ρ(ΣH2S) was significantly lower than that of other treatments. The ρ(Fe2+) in the surface-sediment water was 0.54 mg/L, which corresponds only 25.3–33.7% that of the black-water groups. Fe2+ accounted for 25.2% of the total iron, being considerably lower than ~40.0% of the black-water groups. The concentration of acid-volatile sulfides was 0.51 µg/g, which corresponds only 14.6–17.2% that of the black-water groups. Overall, plow-tillage helped to physically improve sediment in areas of algal accumulation. Plow-tillage could help turn surface-sediment overloaded with organic pollutants to the lower-layer, blocking material migration and supply of contaminated surface-sediment, and controlling anaerobic microbial activity. It could prevent the formation of black water-generating substances in the water column where algae accumulate and die, effectively preventing the occurrence of black water.
VL  - 7
IS  - 2
ER  -

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