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Contrasting the Water Quality and Bacterial Community Patterns in Shallow and Deep Lakes: Manyas vs. Iznik

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Gözde Özbayram at Istanbul University
Gözde Özbayram
Latife Köker at Istanbul University
Latife Köker
Reyhan Akçaalan at Istanbul University
Reyhan Akçaalan
Fatih Aydin at Istanbul University
Fatih Aydin
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The objectives of this study are to monitor the physicochemical properties of two freshwater lakes with different chemical characteristics and trophic status over a year (2019) and assess the bacterial diversity by a high-throughput sequencing method for a certain time. Carlson Trophic Index analysis revealed that, whereas the deep lake, Iznik Lake, (TSImean = 48.9) has mesotrophic characteristics, the shallow lake Manyas Lake (TSImean = 74.2) was found at a hypertrophic status. The most important parameters controlling water qualities in the lakes were temperature, alkalinity, and phosphate levels. Although the bacterial communities were dominated by the same phyla (Cyanobacteria, Bacteroidetes, Actinomicrobia, Proteobacteria, and Verrucomicrobia) in both lakes, the communities differed distinctly at the lower levels. Whereas Sporichthyaceae in Manyas Lake accounted for 10% of the total reads, the major share of the sequences was assigned to Cyanobacteria Family I (8%) in Iznik Lake. The hypertrophic Manyas Lake had a more diverse bacterial community rather than Iznik Lake and contained higher numbers of unique Operational Taxonomic Units.
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Environmental Management (2021) 67:506–512
https://doi.org/10.1007/s00267-020-01357-7
Contrasting the Water Quality and Bacterial Community Patterns in
Shallow and Deep Lakes: Manyas vs. Iznik
E. Gozde Ozbayram 1●Latife Koker 1●Reyhan Akçaalan 1●Fatih Aydın1●Ali Ertürk 1●Orhan Ince 2●
Meriç Albay 1
Received: 12 May 2020 / Accepted: 28 August 2020 / Published online: 5 September 2020
© Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract
The objectives of this study are to monitor the physicochemical properties of two freshwater lakes with different chemical
characteristics and trophic status over a year (2019) and assess the bacterial diversity by a high-throughput sequencing
method for a certain time. Carlson Trophic Index analysis revealed that, whereas the deep lake, Iznik Lake, (TSImean =48.9)
has mesotrophic characteristics, the shallow lake Manyas Lake (TSImean =74.2) was found at a hypertrophic status. The
most important parameters controlling water qualities in the lakes were temperature, alkalinity, and phosphate levels.
Although the bacterial communities were dominated by the same phyla (Cyanobacteria, Bacteroidetes, Actinomicrobia,
Proteobacteria, and Verrucomicrobia) in both lakes, the communities differed distinctly at the lower levels. Whereas
Sporichthyaceae in Manyas Lake accounted for 10% of the total reads, the major share of the sequences was assigned to
Cyanobacteria Family I (8%) in Iznik Lake. The hypertrophic Manyas Lake had a more diverse bacterial community rather
than Iznik Lake and contained higher numbers of unique Operational Taxonomic Units.
Keywords Bacterial community ●Illumina®MiSeq™●Water quality ●16S rRNA ●Manyas Lake ●İznik Lake
Introduction
Freshwater lakes have critical roles in ecological and eco-
nomic perspectives, whereas it is a habitat for a diverse
biological community, it is also a resource for human
consumption (Ma et al. 2018). In these ecosystems, bacteria
play a vital role in ecosystem services and have an impact
on water quality (Newton et al. 2011) in which the profile is
highly dependent on biotic factors and physicochemical
characterization of the water (Zwirglmaier et al. 2015).
Although, the bacterial community is fundamental for
ecosystem processes, much uncertainty still exists about the
diversity and function in the lake ecosystems.
Determination of water quality is a great concern for the
lakes indicating the health of the ecosystem as well as the
source of nutrient and pollutant loads (Wang et al. 2019).
Lakes can be classified into three trophic status regarding
their biological activity namely; oligotrophic, mesotrophic,
and eutrophic lakes (Feng et al. 2019) in which the trophic
status of the lakes gives information about the function and
current structure of the lakes and enables to predict future
trends (Wang et al. 2019). Moreover water quality is a key
factor affecting the bacterial community patterns and
diversity. Environmental variables such as temperature, pH,
nutrient concentrations alter bacterial community structure
in the freshwater lakes (Feng et al. 2019).
Recent developments on next-generation sequencing
methods resulted to have high-quality data, which enables
deep characterization of complex microbial communities
and considerable literature has grown up to increase our
understanding of the microbial community compositions of
freshwater habitats by metagenomic analyses (Diao et al.
2017; Ji et al. 2018).
There are 200 natural lakes in Turkey. Although water
quality and cyanobacterial diversity monitoring have been
conducted in some of those lakes (Albay and Akcaalan
2003; Akcaalan et al. 2009), much less is known about the
*E. Gozde Ozbayram
gozde.ozbayram@istanbul.edu.tr
1Department of Marine and Freshwater Resources Management,
Faculty of Aquatic Sciences, Istanbul University, Fatih,
34134 Istanbul, Turkey
2Department of Environmental Engineering, Faculty of Civil
Engineering, Istanbul Technical University, Maslak,
34469 Istanbul, Turkey
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  • Sep 2018
  • SCI TOTAL ENVIRON
Our study assessed the actual water situation in the estuarine area of Lake Wuli, Meiliang Bay, Lake Taihu, China, based on eutrophication levels and status of water quality using the trophic level index (TLI) and water quality index (WQI) methods. In the wet (August 2017) and dry (March 2018) seasons, 22 estuarine areas were tested at 69 sampling sites, which included lake and rivers. Five parameters—chlorophyll a (Chl-a), total phosphorus (TP), total nitrogen (TN), Secchi disk (SD) and permanganate index (CODMn)—were measured to calculate the TLI, and 15 parameters—temperature (T), pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), TN, TP, ammonium (NH4-N), nitrate (NO3-N), nitrite (NO2-N), CODMn, calcium (Ca²⁺), magnesium (Mg²⁺), chloride (Cl⁻) and phosphate (PO4-P)—were measured to calculate the WQI. The average TLI and WQI values in the wet season were 61.69 and 60.70, respectively, and the eutrophication level and water quality status were worse than that in the dry season (TLI: 57.40, WQI: 65.74). Significant differences were observed between three parts of Lake Wuli (West, Middle and East). Regardless of wet or dry season, East Wuli had worse eutrophication levels and water quality status than the other parts, whereas West Wuli showed less severe levels. DO, TN and CODMn used in the minimum WQI (WQImin) were the most effective parameters in our study. WQImin had stricter standards than WQI when analyzing water quality in the estuarine area of Wulihu. Factor analysis from principal component analysis (PCA) indicated that N might be the main factor affecting water quality of the most eastern sites in the wet season, and P may be the main factor in the dry season. Our results provide a valuable contribution to inform decision-making for the management of water environments by providing the actual water situation of the estuarine area of Lake Wuli.
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