Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
3.1
2.4
Journals
Diversity
Special Issues
Freshwater Siliceous Microeukaryotes
share announcement

Freshwater Siliceous Microeukaryotes

A special issue of Diversity (ISSN 1424-2818). This special issue belongs to the section "Microbial Diversity and Culture Collections".

Deadline for manuscript submissions: closed (1 May 2022) | Viewed by 11198

Special Issue Editor

Prof. Yelena Valentinovna Likhoshway

E-Mail Website
Guest Editor
Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
Interests: freshwater ecosystems; diversity; diatoms; microbial communities; evolution

Special Issue Information

Dear Colleagues,

The Diversity journal is about to launch a Special Issue dedicated to diatom diversity in the lakes.

Diatoms are highly diverse and widespread almost in all inland waters, whether in oligotrophic or brackish, frozen or hot waters, each having different acidity and conductivity. Studying diatoms in lakes gives free rein to researchers, as it allows identifying diversity and tracing how it changes in existent lakes depending on environmental conditions as well as drawing conclusions about the impact of anthropogenous and natural factors on a lake. This also enables us to see how the diversity of diatoms was changing during the active growth of agriculture and industry based on the upper layer of the sediment records, and, if we go a bit more deeply, to follow the evolution of diatoms for millions and millions of years as well as to draw conclusions about the history of formation of a water body, its level and trophicity fluctuations, and even global climate change. The diversity of diatoms is thus a very important topic for study. In this issue, we would like to invite authors for discussion of the following problems:

  • Constitution of a species in diatoms; morphological, genetic, reproductive isolation criteria in identifying a species
  • Limits of the morphological variability of species depending on life cycle stages and cultivation conditions
  • Dependence of diversity on environmental conditions and indicator species
  • Biogeography; diversity in post-glacial lakes and scenarios of species dispersal
  • Diversity in ancient lakes at the present time compared with post-glacial lakes and from historical prospective; endemic species; biodiversity formation centers based on ancient sediment analysis.

In addition to diatoms, other protists that form scales of biogenic silica, such as scaly chrysophytes, heterotrophic protists, and centrochelid heleozoa, can also be objects of consideration. These microeukaryotes are sensitive indicators of changes in the habitat, and their diversity changes depending on changes in environmental parameters, especially temperature, therefore, their study is relevant in connection with the observed trend of climate warming.As a food source, they can influence the variety of consumers and determine their specialization and evolution. The siliceous elements of the scales retain their species-specific structure, and after the destruction of cells, they can be buried in the bottom sediments of reservoirs and serve as evidence of their presence in the ecosystem of the reservoir in the past. Thus, new information on changes in the diversity of siliceous microeukaryotes depending on changes in the habitat can be useful in assessing the state of freshwater ecosystems in the present and in the past, as well as in making forecasts of their changes.

Prof. Yelena Valentinovna Likhoshway
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Diversity is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Diatom diversity and Ecology
  • Freshwater Lakes
  • Extreme Environments
  • Biogeography
  • Endemics
  • Morphological and molecular variability
  • Species concept
  • Succession

Published Papers (4 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

21 pages, 4136 KiB  
Article
Response of Diatoms to the Changing Water Quality in the Myristica Swamps of the Western Ghats, India
by Mital Thacker and Balasubramanian Karthick
Diversity 2022, 14(3), 202; https://doi.org/10.3390/d14030202 - 09 Mar 2022
Cited by 5 | Viewed by 3996
Abstract
Myristica swamps are one of the rarest wetland ecosystems within the sub-tropical evergreen forests of the Western Ghats, India. As their name indicates, they harbor trees belonging to the ancient family Myristicaceae. Due to the waterlogged conditions and high humic decomposition, these [...] Read more.
Myristica swamps are one of the rarest wetland ecosystems within the sub-tropical evergreen forests of the Western Ghats, India. As their name indicates, they harbor trees belonging to the ancient family Myristicaceae. Due to the waterlogged conditions and high humic decomposition, these swamps are acidic, harbor rare and endemic biotas, and provide ecosystem services to humans. Monitoring this rare ecosystem is crucial because the swamps that once formed a large hydrological network across the Western Ghats are now confined to isolated patches due to human disturbance such as agricultural interventions, roads, and dam construction. Due to the change in land use, there is also a drastic change in water chemistry and associated biodiversity. Biomonitoring is more precise than physical and chemical monitoring. So, the current study aimed to undertake a comprehensive analysis of the physical, chemical, and biological assessment of these swamps. The diatom assemblages are strongly affected by water chemistry and serve as a powerful indicator of environmental changes in the freshwater aquatic systems. However, there is no information on diatom assemblages in these swamps, and the present study aimed to determine the diatom assemblage structure in the Myristica swamps and their response to changing water quality. Diatom samples were taken at 17 different swamps across the central Western Ghats, and a set of environmental parameters was evaluated. Analysis revealed a total of 91 species of diatoms belonging to 27 genera across the 17 sites, from which 44 diatom species showed restricted distribution to this unique environment. Overall, the dominant diatom genera inside the swamps included, Navicula (19.8%), Gomphonema (16%), Eunotia (13.3%), Ulnaria (9.4%), Achnanthidium (8%), Frustulia (6.2%), Planothidium (5.2%), and Brachysira (2.8%). High diatom species richness was observed in the swamps having less anthropogenic disturbance, and diatom assemblage composition was primarily determined by dissolved oxygen, pH, and conductivity. The significant number of geographically restricted taxa in this study points towards our limited understanding of this tropical biome and calls for a dire need for more studies from here, not only to improve our knowledge concerning the diversity, ecology, and biogeography of these diatoms but to further encourage their use in applied (paleo) environmental sciences. Our results indicate that diatoms can prove useful environmental indicators even in harsh environments like swamps and can be a potential tool for assessing ecological and climatic change. Full article
(This article belongs to the Special Issue Freshwater Siliceous Microeukaryotes)
►▼ Show Figures

Figure 1

12 pages, 2077 KiB  
Article
Is a High Abundance of Spring Diatoms in the Photic Zone of Lake Baikal in July 2019 Due to an Upwelling Event?
by Mikhail Grachev, Yurij Bukin, Vadim Blinov, Oleg Khlystov, Alena Firsova, Maria Bashenkhaeva, Oxana Kamshilo, Lubov Titova, Elvira Bairamova, Yekaterina Bedoshvili, Maria Sakirko and Yulia Zakharova
Diversity 2021, 13(10), 504; https://doi.org/10.3390/d13100504 - 19 Oct 2021
Cited by 4 | Viewed by 1739
Abstract
A high abundance of planktonic microalgae is typically thought to be related to their ‘bloom’, that is, to active population growth. Diatom blooms in the photic zone of Lake Baikal generally occur during hydrological spring (April–June); when the summer arrives and the surface [...] Read more.
A high abundance of planktonic microalgae is typically thought to be related to their ‘bloom’, that is, to active population growth. Diatom blooms in the photic zone of Lake Baikal generally occur during hydrological spring (April–June); when the summer arrives and the surface water temperature increases, diatoms are replaced by other microalgae. In July 2019, we found a concentration of the diatom Fragilaria radians at a station in South Baikal that was extremely high for that season. This species generally blooms in spring, but in spring (May) of 2019, this alga was nearly absent from the phytoplankton population. Microscopic analysis of the sample taken in July 2019 revealed that the cells were in a dormant stage. The species composition of microalgae in phytoplankton samples from May 2018 and July 2019 was similar. According to the temperature profile analysis, a summer upwelling event from a depth of ca. 100 m occurred in 2019. We hypothesised that this event caused the resuspension of microalgae, including Fragilaria radians, which were deposited on the slopes of the lake in 2018. Hence, the high abundance is not always a ‘bloom’ or an active growth. Full article
(This article belongs to the Special Issue Freshwater Siliceous Microeukaryotes)
►▼ Show Figures

Graphical abstract

26 pages, 6597 KiB  
Article
Diversity and Ecology of Diatoms in Pliocene Deposits of the Tunka Valley (Baikal Rift Zone)
by Lyubov’ Titova, Abdulmonem Hassan, Ivan Mikhailov, Elena Rodionova, Sergei Rasskazov and Мarina Usoltseva
Diversity 2021, 13(10), 479; https://doi.org/10.3390/d13100479 - 29 Sep 2021
Cited by 6 | Viewed by 2277
Abstract
Fossil diatoms are an excellent tool for reconstructing the palaeoenvironmental and palaeogeographic changes involving lacustrine systems. In this work, the diatom content of Pliocene sediments recovered from a core extracted in the Tunka Basin (Baikal Rift Zone, Russia) is described. Revealed by light [...] Read more.
Fossil diatoms are an excellent tool for reconstructing the palaeoenvironmental and palaeogeographic changes involving lacustrine systems. In this work, the diatom content of Pliocene sediments recovered from a core extracted in the Tunka Basin (Baikal Rift Zone, Russia) is described. Revealed by light and scanning electron microscopy, 170 species of diatoms were found. Benthic, alkaliphilic, indifferent, cosmopolitan, and oligosaprobe species predominated. Ecological, geographical, and stratigraphic analysis of diatoms showed two ecozones, differing in taxonomic diversity of species. From the data obtained, palaeoenvironmental conditions of these zone formations have been reconstructed. It was shown that during the period corresponding to sedimentation in Ecozone II, the reservoir was cooler, as suggested by the increase of arctic-alpine taxa. The absence of Baikal Pliocene endemics and the presence of local endemics in the Tunka core indicate that there was no geographical connection between the palaeolake of the Tunka Valley and Lake Baikal during the Pliocene. Full article
(This article belongs to the Special Issue Freshwater Siliceous Microeukaryotes)
►▼ Show Figures

Figure 1

14 pages, 3959 KiB  
Article
Impact of Algicidal Bacillus mycoides on Diatom Ulnaria acus from Lake Baikal
by Yekaterina Bedoshvili, Elvira Bayramova, Nikolay Sudakov, Igor Klimenkov, Maria Kurilkina, Yelena Likhoshway and Yulia Zakharova
Diversity 2021, 13(10), 469; https://doi.org/10.3390/d13100469 - 27 Sep 2021
Cited by 6 | Viewed by 2034
Abstract
Algae–bacteria interactions play an important role in water ecosystems. In this work, the BS2-15 algicidal strain was isolated from the bottom sediments of Lake Baikal and identified as Bacillus mycoides on the basis of 16S rDNA sequencing, its described ultrastructure, and biochemical properties. [...] Read more.
Algae–bacteria interactions play an important role in water ecosystems. In this work, the BS2-15 algicidal strain was isolated from the bottom sediments of Lake Baikal and identified as Bacillus mycoides on the basis of 16S rDNA sequencing, its described ultrastructure, and biochemical properties. B. mycoides BS2-15 was demonstrated to have a strong algicidal effect against a freshwater diatom culture of Ulnaria acus, inhibiting its growth and increasing frustules fragility. By analyzing the impact of bacterial filtrate onto the cells of U. acus, we demonstrated that perhaps an algicidal compound is produced by bacteria independently in the presence of diatoms in a medium. Using methods of TUNEL and confocal microscopy, we revealed that the bacterial algicidal effect on the diatom cells results in DNA fragmentation, nucleus destruction, and neutral lipid accumulation. This phenomenon highlights the complexity of algae–bacteria interactions and their potential role in regulating water ecosystem microbial populations. Full article
(This article belongs to the Special Issue Freshwater Siliceous Microeukaryotes)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-4
Back to TopTop