The current study was carried out under the auspices of Framework Plan 3 and included high-temperature areas that declined in the waiting category in R\u00c12. The areas were Tr\u00f6lladyngja and Austurengjahver in Reykjanes, Fremrin\u00e1mar and \u00dever\u00e1rdalur and Innstidalur in the Hengill area. The aim of the study was to assess the diversity and rarity of thermophilic microorganisms in the above areas. The methodology was based on DNA analysis independent of culture. DNA was isolated from samples and species-identifying genes amplified and sequenced and the sequences compared to sequences in gene banks and from previous studies. A total of 118 samples were collected in 2015 and were able to be sequenced approx. Their 59%. A total of 10 million 16S gene sequences were obtained from sequencing, which dropped to almost six million after all quality and length conditions had been met. Most rows were obtained from Innstadalur, or 2,176,174, but fewest 286,039 from Tr\u00f6lladyngja. The diversity of microorganisms in each region was assessed by comparing the number of arrays, number of species, collection curves, and Shannon's diversity coefficient. The total number of samples and sequences of each area was very different and reflect its diversity. When the series were classified as species with 97% matching, it was found that most species came from \u00dever\u00e1rdalur, or about 42 thousand, but the fewest from Tr\u00f6lladyngja, or about 9 thousand. More than 12 thousand species were found in samples from Fremrin\u00e1mur, which came as a surprise as the area and the samples seemed homogeneous and such diversity was not expected. All major thermal bacteria were found in the samples, both Ancient Bacteria and Bacteria. Special groups were found especially within the Thaumarchaeota faction. The assessment of diversity in individual areas with collection curves and diversity coefficient was based on the smallest number of rows or 286,039 from Tr\u00f6lladyngja. The greatest diversity of species was in \u00dever\u00e1rdalur and Innstadalur and the least at Tr\u00f6lladyngja and Austurengjahver, but Fremrin\u00e1mar was in between. Collection curves gave the same result. Biodiversity (H) gave a different ranking. There were \u00dever\u00e1rdalur and Fremrin\u00e1mar with the most diversity (H = 8 and 7.7), then Innstidalur but Tr\u00f6lladyngja and Austurengjahver (H = 6) ran the train. Rarity was assessed on the basis of the number and proportion of unknown species in comparison with the Silva database. The number of unknown species was greatest in \u00dever\u00e1rdalur and Innstadalur, both with over 1000, Fremrin\u00e1mar with 756 and Tr\u00f6lladyngja and Austurengjahver with over four hundred unknown species. National rarity was assessed by comparing data from individual regions in previous studies and examining whether a match occurred. It turned out that the geothermal area in Fremrin\u00e1mur contains a large number of species that have no equivalent in other thermal areas.<\/p>\n\n\n\n
The current project was requested by the Master Plan for Nature Protection and Energy Utilization and aimed at geothermal areas which had not been classified for preservation or utilization during Masterplan 2. The geothermal areas investigated were Tr\u00f6lladyngja and Austurengjahver at Reykjanes, Fremrin\u00e1mar and \u00dever\u00e1rdalur and Innstidalur at Hengill. The goal of the project was to estimate biodiversity and rarity of thermophiles inhabiting the areas mentioned. The methods used were DNA based and were performed on DNA extracted from primary samples (culture independent). Microbial species identification was performed by amplification and sequencing of 16S rRNA genes and comparison with sequence databases and previous research. A total of 118 samples were collected in 2015 of which 59% were sequenced. The total sequencing yield was 10 million reads, of which 6 million passed quality assessment and were used for downstream analyzes. The largest proportion of the reads were obtained from Innstidalur samples, 2,176,174 reads, and the lowest proportion from Tr\u00f6lladyngja, 286,036 reads. The biodiversity of microorganisms within each area was estimated using the number of phyla and species, rarefaction curves and Shannons' biodiversity index. The total number of species identified varied between sites and reflected the diversity of the geothermal area and the total amount of sequences obtained. Using a cut-off value of 97% similarity, the sequences were classified to the species level. The highest number of species, approximately 42.000, were identified in samples from \u00dever\u00e1rdalur and the lowest number, approximately 9.000, in samples from Tr\u00f6lladyngja. Roughly 12,000 species were found in samples from Fremrin\u00e1mar, which was surprising as the area and the samples appeared rather homogenous and such diversity was therefore not expected. All the main thermophilic taxa of the Bacteria and Archaea domains were identified in the samples. Unknown groups were found especially within the phylum of Thaumarchaeota. For the rarefaction and biodiversity index estimates the lowest number of sequence reads, Tr\u00f6lladyngja, was used as reference. The species diversity was found to be highest in \u00dever\u00e1rdalur and Innstidalur, the lowest in Tr\u00f6lladyngja and Austurengjahver, and intermediate in Fremrin\u00e1mar. Rarefaction curves showed the same results. The calculated biodiversity index (H) gave different results, indicating highest diversity in \u00dever\u00e1rdalur and Fremrin\u00e1mar (H = 8 and 7,7 respectively), intermediate in Innstidalur (H = 7.0) and lowest in Tr\u00f6lladyngja and Austurengjahver (H = 6). Rarity was estimated as the number of species which could not be identified by comparison to the Silva database. The highest number of unidentified species was roughly 1000 in \u00dever\u00e1rdalur and Innstidalur, 756 in Fremrin\u00e1mar and between 300- 400 in Tr\u00f6lladyngja and Austurengjahver. The rarity was also estimated by comparing data obtained in the current project with data from previous projects. The analysis revealed a particularly high number of unique species in Fremrin\u00e1mar that have not been identified in other geothermal areas in Iceland.<\/p>","protected":false},"excerpt":{"rendered":"
Ranns\u00f3knir \u00e1 hitak\u00e6rum \u00f6rverum \u00e1 h\u00e1hitasv\u00e6\u00f0um \u00e1 Reykjanesi, Hengilssv\u00e6\u00f0i og Fremrin\u00e1mum. Unni\u00f0 fyrir Fagh\u00f3p 1 \u00ed Ramma\u00e1\u00e6tlun 3 \/ Thermophilic […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[15],"tags":[458,459,460,461,462,463,464,465,466,467,468],"class_list":["post-30229","post","type-post","status-publish","format-standard","hentry","category-skyrsla","tag-bacteria-and-archaea","tag-bakteriur","tag-biodiversity","tag-dna-radgreiningar","tag-dna-sequencing","tag-fagaeti","tag-fjolbreytileiki","tag-fornbakteriur","tag-hitakaerar-orverur","tag-rarity","tag-thermophiles"],"acf":[],"yoast_head":"\n