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Xue Z, Zhu W, Bai S, Chen M, Chen X, Liu J, Lv Y. Wind-driven post-bloom dispersion of Microcystis in a large shallow eutrophic lake: A case study in Lake Taihu. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 941:173512. [PMID: 38815825 DOI: 10.1016/j.scitotenv.2024.173512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/01/2024]
Abstract
To clarify the wind-driven post-bloom dispersion range of Microcystis, which originally clustered on the water surface, an Individual-Based Model (IBM) of Microcystis movement considering the combined effects of wind and light was developed based on actual hydrodynamic data and Microcystis biomass. After calibrating the effects of hydrodynamics and light, 66 cases of short-term (within a week) post-bloom with satellite images from 2011 to 2017 were simulated. The results showed that there were three short-term post-bloom types: vertical reduction (VR), horizontal reduction (HR) and mixed reduction (MR). For VR type, the cyanobacterial bloom reduction rate was rapid (>160 km2/day), but the dispersion range of Microcystis was limited (<2 km/day), and a larger bloom area was likely to form in the original location when wind speed decreased. For HR type, the cyanobacterial bloom reduction rate was slow (<10 km2/day), but Microcystis exhibited a broad dispersion range (>4 km/day), often leading to smaller, thicker, and longer-lasting cyanobacterial blooms downwind, albeit with a lower probability of occurrence. The characteristics of MR lay between the two aforementioned types.
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Affiliation(s)
- Zongpu Xue
- Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210098, PR China
| | - Wei Zhu
- Institute of Water Science and Technology, Hohai University, Nanjing 210098, PR China.
| | - Song Bai
- Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210098, PR China
| | - Ming Chen
- Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210098, PR China
| | - Xinqi Chen
- Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210098, PR China
| | - Jun Liu
- Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210098, PR China
| | - Yi Lv
- College of Environment, Hohai University, Nanjing 210098, PR China
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Zhang Y, Yang T, Zhang Y, Xu G, Lorke A, Pan M, He F, Li Q, Xiao B, Wu X. Assessment of in-situ monitoring and tracking the vertical migration of cyanobacterial blooms using LISST-HAB. WATER RESEARCH 2024; 257:121693. [PMID: 38728785 DOI: 10.1016/j.watres.2024.121693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 04/26/2024] [Accepted: 04/28/2024] [Indexed: 05/12/2024]
Abstract
Cyanobacterial harmful algal blooms (cyanoHABs) are becoming increasingly common in aquatic ecosystems worldwide. However, their heterogeneous distributions make it difficult to accurately estimate the total algae biomass and forecast the occurrence of surface cyanoHABs by using traditional monitoring methods. Although various optical instruments and remote sensing methods have been employed to monitor the dynamics of cyanoHABs at the water surface (i.e., bloom area, chlorophyll a), there is no effective in-situ methodology to monitor the dynamic change of cell density and integrated biovolume of algae throughout the water column. In this study, we propose a quantitative protocol for simultaneously measurements of multiple indicators (i.e., biovolume concentration, size distribution, cell density, and column-integrated biovolume) of cyanoHABs in water bodies by using the laser in-situ scattering and transmissometry (LISST) instrument. The accuracy of measurements of the biovolume and colony size of algae was evaluated and exceeded 95% when the water bloom was dominated by cyanobacteria. Furthermore, the cell density of cyanobacteria was well estimated based on total biovolume and mean cell volume measured by the instrument. Therefore, this methodology has the potential to be used for broader applications, not only to monitor the spatial and temporal distribution of algal biovolume concentration but also monitor the vertical distribution of cell density, biomass and their relationship with size distribution patterns. This provides new technical means for the monitoring and analysis of algae migration and early warning of the formation of cyanoHABs in lakes and reservoirs.
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Affiliation(s)
- Yanxue Zhang
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tiantian Yang
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yan Zhang
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gang Xu
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Andreas Lorke
- Institute for Environmental Sciences, University of Kaiserslautern-Landau (RPTU), Landau 76829, Germany
| | - Min Pan
- Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming Dianchi & Plateau Lakes Institute, Kunming 650228, China
| | - Feng He
- Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming Dianchi & Plateau Lakes Institute, Kunming 650228, China
| | - Qingman Li
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Bangding Xiao
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming Dianchi & Plateau Lakes Institute, Kunming 650228, China
| | - Xingqiang Wu
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming Dianchi & Plateau Lakes Institute, Kunming 650228, China.
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3
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Feng G, Cao J, Chen H, Meng XZ, Duan Z. Potential gap in understanding cyanoHABs: Light-dependent morphological variations in colonial cyanobacterium Microcystis. HARMFUL ALGAE 2024; 134:102622. [PMID: 38705618 DOI: 10.1016/j.hal.2024.102622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/01/2024] [Accepted: 03/20/2024] [Indexed: 05/07/2024]
Abstract
Colony formation is a crucial characteristic of Microcystis, a cyanobacterium known for causing cyanobacterial harmful algal blooms (cyanoHABs). It has been observed that as Microcystis colonies grow larger, they often become less densely packed, which correlates with a decrease in light penetration. The objective of this study was to investigate the effects of light limitation on the morphological variations in Microcystis, particularly in relation to the crowded cellular environment. The results indicated that when there was sufficient light (transmittance = 100 %) to support a growth rate of 0.11±0.01 day-1, a significant increase in colony size was found, from 466±15 μm to 1030±111 μm. However, under light limitation (transmittance = 50 % - 1 %) where the growth rate was lower than 0, there was no significant improvement in colony size. Microcystis in the light limitation groups exhibited a loose cell arrangement and even the presence of holes or pores within the colony, confirming the negative correlation between colony size and cell arrangement. This pattern is driven by regional differences in growth within the colony, as internal cells have a significantly lower frequency of division compared to peripheral cells, due to intra-colony self-shading (ICSS). The research demonstrates that Microcystis can adjust its cell arrangement to avoid excessive self-shading, which has implications for predicting and controlling cyanoHABs. These findings also contribute to the understanding of cyanobacterial variations and can potentially inform future research on the diverse phycosphere.
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Affiliation(s)
- Ganyu Feng
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, Jiangsu 210098, China; Shanghai Institute of Pollution Control and Ecological Security, 1239 Siping Road, Shanghai 200092, China.
| | - Jun Cao
- National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai University, 1 Xikang Road, Nanjing, Jiangsu 210098, China
| | - Huaimin Chen
- School of Materials Engineering, Changzhou Vocational Institute of Industry Technology, 28 Mingxinzhong Road, Changzhou 213164, China
| | - Xiang-Zhou Meng
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, 1239 Siping Road, Shanghai 200092, China
| | - Zhipeng Duan
- College of Environment, Hohai University, 1 Xikang Road, Nanjing, Jiangsu 210098, China
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Zhang M, Zhang Y, Zhou Y, Zhang Y, Shi K, Jiang C. Influence of cyanobacterial bloom accumulation and dissipation on underwater light attenuation in a large and shallow lake. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:79082-79094. [PMID: 35701699 DOI: 10.1007/s11356-022-21384-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
Cyanobacterial bloom accumulation and dissipation frequently occur in Lake Taihu, a typically shallow, eutrophic lake due to wind wave disturbance. However, knowledge of the driving mechanisms of cyanobacterial blooms on underwater light attenuation is still limited. In this study, we collected a high-frequency in situ monitoring of the wind field, underwater light environment, and surface water quality to elucidate how cyanobacterial bloom accumulation and dissipation affect the variations in underwater light attenuation in the littoral zone of Lake Taihu. Results showed that cyanobacterial blooms significantly increased the diffuse attenuation coefficient of ultraviolet-B (Kd(313)), ultraviolet-A (Kd(340)), and photosynthetically active radiation (Kd(PAR)); the scattering of total suspended matter (bbp(λ)); and the absorption of phytoplankton (aph(λ)) and chromophoric dissolved organic matter (CDOM, ag(λ)) (p < 0.01). The Kd(PAR) decreased quickly during the processes of bloom dissipation, but the decrease of Kd(313) and Kd(340) lagged 0.5 day. Our results suggested that cyanobacterial blooms could increase particle matters and elevated the production of autochthonous CDOM, resulting in underwater light attenuation increase. Ultraviolet radiation (UVR) and PAR attenuation both have significant responses to cyanobacterial blooms, but the response processes were distinct due to the different changes of particle and dissolved organic matters. Our study unravels the driving mechanisms of cyanobacterial blooms on underwater light attenuation, improving lake ecosystem management and protection.
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Affiliation(s)
- Manxue Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- College of Water Resources and Hydrology, Hohai University, Nanjing, 210098, China
| | - Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Yongqiang Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yibo Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kun Shi
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cuiling Jiang
- College of Water Resources and Hydrology, Hohai University, Nanjing, 210098, China
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Shi L, Cai Y, Gao S, Zhang M, Chen F, Shi X, Yu Y, Lu Y, Wu QL. Gene expression pattern of microbes associated with large cyanobacterial colonies for a whole year in Lake Taihu. WATER RESEARCH 2022; 223:118958. [PMID: 35994786 DOI: 10.1016/j.watres.2022.118958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/05/2022] [Accepted: 08/06/2022] [Indexed: 06/15/2023]
Abstract
Large cyanobacterial colonies, which are unique niches for heterotrophic bacteria, are vital for blooming in eutrophic waters. However, the seasonal dynamics of molecular insights into microbes in these colonies remain unclear. Here, the community composition and metabolism pattern of microbes inhabiting large cyanobacterial colonies (> 120 µm, collected from Lake Taihu in China) were investigated monthly. The community structure of total microbes was mostly influenced by chlorophyll a (Chl a), total phosphorus (TP) concentration, dissolved oxygen, and temperature, whereas the colony-associated bacteria (excluding Cyanobacteria) were mostly influenced by total organic carbon, NO3-, and PO43- concentrations, indicating different response patterns of Cyanobacteria and the associated bacteria to water nutrient conditions. Metatranscriptomic data suggested that similar to that of Cyanobacteria, the gene expression patterns of the most active bacteria, such as Proteobacteria and Bacteroidetes, were not strictly dependent on season but separated by Chl a concentrations. Samples in July and September (high-bloom period) and February and March (non-bloom period) formed two distinct clusters, whereas those of other months (low-bloom period) clustered together. The accumulation of transcripts for pathways, such as phycobilisome from Cyanobacteria and bacterial chemotaxis and flagellum, phosphate metabolism, and sulfur oxidation from Proteobacteria, was enriched in high- and low-bloom periods than in non-bloom period. Network analyses revealed that Cyanobacteria and Proteobacteria exhibited coordinated transcriptional patterns in almost all divided modules. Modules had Cyanobacteria-dominated hub gene were positively correlated with temperature, Chl a, total dissolved phosphorus, and NH4+ and NO2- concentrations, whereas modules had Proteobacteria-dominated hub gene were positively correlated with TP and PO43-. These results indicated labor division might exist in the colonies. This study provided metabolic insights into microbes in large cyanobacterial colonies and would support the understanding and management of the year-round cyanobacterial blooms.
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Affiliation(s)
- Limei Shi
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China.
| | - Yuanfeng Cai
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008, China
| | - Shengling Gao
- Biological Experiment Teaching Center, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Min Zhang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China
| | - Feizhou Chen
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China
| | - Xiaoli Shi
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China
| | - Yang Yu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China
| | - Yaping Lu
- Biological Experiment Teaching Center, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Qinglong L Wu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China; Sino-Danish Center for Science and Education, University of Chinese Academy of Sciences, Beijing, China; The Fuxianhu Station of Plateau Deep Lake Research, Chinese Academy of Sciences, Chengjiang, Yunnan Province, China.
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6
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Wang Z, Xie C, Zhang J, Ji S, Zhao J, Nie X. The responses of Scrippsiella acuminata to the stresses of darkness: antioxidant activities and formation of pellicle cysts. HARMFUL ALGAE 2022; 115:102239. [PMID: 35623691 DOI: 10.1016/j.hal.2022.102239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 03/03/2022] [Accepted: 04/20/2022] [Indexed: 06/15/2023]
Abstract
In order to understand the strategy of Scrippsiella acuminata to cold dark environment, the antioxidant responses and the formation of pellicle cysts of S. acuminata to darkness at 8°C and 20°C were investigated. Cell densities decreased significantly after 96 h dark treatment, and no live cells were observed after 9-days dark treatments. The darkness stress generally resulted in an increase of antioxidant defenses, including soluble protein, superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA). Cellular soluble protein and SOD activity increased sharply under 20°C darkness, which protected algal cells against the oxidative stress from darkness, and resulted in relatively lower MDA levels. Soluble protein and SOD activity were enhanced under 8°C darkness as well however not in a sharp rise, and higher levels of MDA and GSH were recorded. The results suggested high SOD and protein levels protected cells against harsh darkness stress, while high GSH not only helped algae cells resist dark stress, but also played an important role in low temperature stress. Darkness promoted the formation of pellicle cysts of S. acuminata, and the maximum formation rates were 16.06% to 21.74% at 8°C and 20°C, respectively. Germination of pellicle cysts occurred within 24 h after light exposure, however pellicle cysts could not withstand long-time darkness stress, and all pellicle cysts died after 9-days darkness exposure. The results of this study suggest that S. acuminata is able to overcome temporary cold darkness through forming pellicle cysts.
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Affiliation(s)
- Zhaohui Wang
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China.
| | - Changliang Xie
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Jianneng Zhang
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Shuanghui Ji
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Jiangang Zhao
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China.
| | - Xiangping Nie
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China.
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Xue Z, Zhu W, Zhu Y, Fan X, Chen H, Feng G. Influence of wind and light on the floating and sinking process of Microcystis. Sci Rep 2022; 12:5655. [PMID: 35383194 PMCID: PMC8983747 DOI: 10.1038/s41598-022-08977-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 03/11/2022] [Indexed: 11/09/2022] Open
Abstract
The vertical migration and accumulation of Microcystis colonies is a critical process in algal bloom formation. This work explored the effect of wind and light intensity on the vertical migration of Microcystis colonies. The wind-driven currents, light-driven changes in mass density of colonies, and the effect of colony size was coupled to simulate the vertical motion of colonies via Ansys Fluent and MATLAB. Results showed that light causes Microcystis to exhibit a 'day-sinking and night-floating' (d-n) phenomenon, however, wind weakens the phenomenon by forming a turbulent drag force that inhibits the vertical movement of Microcystis. This study proposed a kinetic ratio-based method, that there is a specific equilibrium turbulent kinetic energy and when turbulent kinetic energy of the water body is greater than the equilibrium turbulent kinetic energy, the d-n phenomenon does not occur. For Lake Taihu, the wind-driven turbulent kinetic energy is usually greater than the equilibrium turbulent kinetic energy. Therefore, Microcystis colonies may not exhibit the d-n phenomenon. Our findings provide a new theoretical basis for current process-based models in simulating algal blooms in large shallow lakes.
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Affiliation(s)
- Zongpu Xue
- College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, People's Republic of China
| | - Wei Zhu
- College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
| | - Yuyang Zhu
- School of Civil Engineering, University of Queensland, Brisbane, 4067, Australia
| | - Xihui Fan
- College of Civil and Transportation Engineering, Hohai University, Nanjing, 210098, People's Republic of China
| | - Huaimin Chen
- College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.,School of Materials Engineering (School of Environmental Engineering), Changzhou Institute of Industry Technology, Changzhou, 213164, People's Republic of China
| | - Ganyu Feng
- College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
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Wang Q, Sun L, Zhu Y, Wang S, Duan C, Yang C, Zhang Y, Liu D, Zhao L, Tang J. Hysteresis effects of meteorological variation-induced algal blooms: A case study based on satellite-observed data from Dianchi Lake, China (1988-2020). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 812:152558. [PMID: 34952086 DOI: 10.1016/j.scitotenv.2021.152558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/23/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
As one of three top-priority eutrophic lakes in China, Dianchi Lake has received national attention due to its severe eutrophication in recent decades. Meteorological factors are the main factors driving the formation and persistence of algae blooms. In addition, meteorological variation-induced algal blooms usually have a hysteresis effect. However, there have been few quantitative studies on this hysteresis effect. In the present study, Landsat images were used to extract the dynamic characteristics of changes in algal blooms in Dianchi Lake from 1988 to 2020. The hysteresis effect of meteorological factors driving algal blooms was studied by employing the modified lag-correlation method. The results showed that the algal blooms in Dianchi Lake were most severe between 1998 and 2008. During the periods of algal blooms, the values of air temperature (AT) and precipitation (PP) were significantly higher, while those wind velocity (WV) and sunshine duration (SSD) were obviously lower, than the corresponding annual mean values. AT and PP were significantly positively correlated with algal bloom factors in both the formation and persistence stages of algal blooms, while SSD and WV both promoted their regression, but these effects were less significant in the persistence period than in the formation period. Moreover, rainfall led to a decrease in SSD and WV, indirectly contributing to algal blooms. Furthermore, AT, PP and SSD are the main factors impacting the duration of persistent blooms. The time periods during which each meteorological factor was most influential were as follows: 1) AT - 25-30 days before the maximum bloom. 2) PP - within the first 10 days before the maximum bloom. 3) Both SSD and WV - 15-20 days before the maximum bloom. The results of this study support the prediction of algal blooms in Dianchi Lake.
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Affiliation(s)
- Quan Wang
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China.
| | - Liu Sun
- School of Mathematics and Information Technology, Yuxi Normal University, Yuxi 653100, China
| | - Yi Zhu
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China
| | - Shuaibing Wang
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China
| | - Chunyu Duan
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China
| | - Chaojie Yang
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China
| | - Yumeng Zhang
- College of Chemistry, Biology and Environment, Yuxi Normal University, Yuxi 653100, China; Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Dejiang Liu
- College of Geography and Land Engineering, Yuxi Normal University, Yuxi 653100, China
| | - Lin Zhao
- College of Geography and Land Engineering, Yuxi Normal University, Yuxi 653100, China
| | - Jinli Tang
- College of Geography and Land Engineering, Yuxi Normal University, Yuxi 653100, China
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