Geothermal Pond Research Articles

Predicting Tilapia Productivity in Geothermal Ponds: A Genetic Algorithm Approach for Sustainable Aquaculture Practices

This study presents a case focused on sustainable farming practices, specifically the cultivation of tilapia (Mozambican and aureus species) in ponds with geothermal water. This research aims to optimize the hydrochemical regime of experimental ponds to enhance the growth metrics and external characteristics of tilapia breeders. The dataset encompasses the hydrochemical parameters and the fish feeding base from experimental geothermal ponds where tilapia were cultivated. Genetic algorithms (GA) were employed for hyperparameter optimization (HPO) of deep neural networks (DNN) to enhance the prediction of fish productivity in each pond under varying conditions, achieving an R2 score of 0.94. This GA-driven HPO process is a robust method for optimizing aquaculture practices by accurately predicting how different pond conditions and feed bases influence the productivity of tilapia. By accurately determining these factors, the model promotes sustainable practices, improving breeding outcomes and maximizing productivity in tilapia aquaculture. This approach can also be applied to other aquaculture systems, enhancing efficiency and sustainability across various species.

Living in Geothermal Energy Plant Emergency Pond: Isolation and Cultivation of Arthrospira platensis to Stressful High Temperature in the Geothermal Ponds

Jeotermal sular yerin derinliklerinde yüksek basınç ve sıcaklıktan dolayı zengin mineraller içeren ve yeryüzüne ilk kez ulaşan sulardır. Bu nedenle, gelecekte mikroalg türlerinin, jeotermal acil durum havuzlarında büyük ölçekli yetiştiriciliği ve jeotermal akışkanların teknoloji optimizasyonu kullanımı açısından elde edilen sonuçlara odaklanacaktır. Jeotermal atıl sudan izole edilen Arthrospira platensis'in farklı besin ortamlarında büyüme performansı araştırıldı. Optik yoğunluk ve kültürdeki hücre sayısı alglerin büyümesinin ana göstergeleridir. Zarrouk ortamı bu tür alglerde hem optik yoğunluk hem de hücre sayısı açısından diğer besin ortamlarına göre daha etkili olduğu gözlenmiştir. A. platensis kültüründe en yüksek hücre sayısı Zarrouk besin ortamında 35,43 x104 hücre mL-1 olarak ölçülmüştür. Bu tür kültür hücre sayıları Spirulina ortamında, kontrol grubunda ve BG11'de sırasıyla 23,75 x104, 6,25 x104 ve 6,25 x104 hücre mL-1 olarak tespit edildi. Bu ortamların alglerin fotosentezi ve hücre büyümesi için gerekli besinleri daha iyi sağladığı düşünülebilir. Özellikle suyun toplam sertliği 21,4±1,04 ppm’den 1,5±0,14 ppm'ye, sülfat miktarı 44±0,49 ppm’den 0 ppm’ye, alkalinitesi 3213±43,5 ppm’den 716±58,9 ppm’ye ve demir içeriği 20,3±2,23 ppm'den 4,1±0,15 ppm'ye düşmüştür. Bu çalışmada Maspo Enerji jeotermal santralinin acil durum havuzu suyunda A. platensis türlerinin üretimi nedeniyle maksimum %43 civarında protein içeren türlerin üretimi gerçekleştirilmiştir. Anahtar kelimeler: Arthrospira platensis, Kültür, Jeotermal enerji santrali, Jeortermal acil durum havuz suyu,

Isolation, Biochemical Characterisation and Identification of Thermotolerant and Cellulolytic Paenibacillus lactis and Bacillus licheniformis.

SUMMARYResearch backgroundCellulose is an ingredient of waste materials that can be converted to other valuable substances. This is possible provided that the polymer molecule is degraded to smaller particles and used as a carbon source by microorganisms. Because of the frequently applied methods of pretreatment of lignocellulosic materials, the cellulases derived from thermophilic microorganisms are particularly desirable.Experimental approachWe were looking for cellulolytic microorganisms able to grow at 50 °C and we described their morphological features and biochemical characteristics based on carboxymethyl cellulase (CMCase) activity and the API® ZYM system. The growth curves during incubation at 50 °C were examined using the BioLector® microbioreactor.Results and conclusionsForty bacterial strains were isolated from fermenting hay, geothermal karst spring, hot spring and geothermal pond at 50 °C. The vast majority of the bacteria were Gram-positive and rod-shaped with the maximum growth temperature of at least 50 °C. We also demonstrated a large diversity of biochemical characteristics among the microorganisms. The CMCase activity was confirmed in 27 strains. Hydrolysis capacities were significant in bacterial strains: BBLN1, BSO6, BSO10, BSO13 and BSO14, and reached 2.74, 1.62, 1.30, 1.38 and 8.02 respectively. Rapid and stable growth was observed, among others, for BBLN1, BSO10, BSO13 and BSO14. The strains fulfilled the selection conditions and were identified based on the 16S rDNA sequences. BBLN1, BSO10, BSO13 were classified as Bacillus licheniformis, whereas BSO14 as Paenibacillus lactis.Novelty and scientific contributionWe described cellulolytic activity and biochemical characteristics of many bacteria isolated from hot environments. We are also the first to report the cellulolytic activity of thermotolerant P. lactis. Described strains can be a source of new thermostable cellulases, which are extremely desirable in various branches of circular bioeconomy.

Genotoxic Assessment of Some Inorganic Compounds in Desert Pupfish (Cyprinodon macularius) in the Evaporation Pond from a Geothermal Plant.

The frequency of micro nucleated erythrocytes in peripheral blood of the desert pupfish (Cyprinodon macularius) from a geothermal effluent pond is determined and compared to organisms kept in an aquarium. The frequency of micronucleated erythrocytes found in pupfish from the geothermal pond is 2.75 (±2.09) and only 0.44 (±0.52) in captivity organisms. Dissolved As in the ponds doubles the 340µgL-1 US-EPA acute quality criteria for aquatic life and Hg equals the 1.77µgL-1 chronic criteria. The organisms with high MNE also have significantly high Se, As and Hg concentrations in muscle and liver. Compared to international maximum allowable limits for fish consumption, there is 81× enrichment for Se, 6× for As and 5× for Hg. Although Se is not significantly enriched in water, it is likely that its bioaccumulation occurs via feeding of detritus. The desert pupfish has a significant resistance to extreme metal accumulations and to recover under unpolluted conditions.

Introduced American Bullfrog Distribution and Diets in Grand Teton National Park

Introduced American Bullfrogs (Lithobates catesbeianus) have been present in Grand Teton National Park since approximately the 1950s, but little is known about their distribution and potential impacts. In this study, we surveyed the current bullfrog distribution and spatial overlap with sympatric native amphibians in the park, and characterized post-metamorphic bullfrog diets from July–September 2015. Despite surveys in multiple large rivers and floodplain habitats, we only documented bullfrogs in a geothermal pond and 5 km of stream channel immediately downstream of this pond. In these waters, bullfrogs overlapped with native amphibians at the downstream end of their distribution, and we did not document native amphibians in bullfrog stomach contents. Larger bullfrogs (SVL ≥ 96 mm) primarily consumed native rodents (especially meadow voles, Microtus pennsylvanicus), while smaller bullfrogs frequently consumed native invertebrates and less frequently consumed non-native invertebrates and fish. Taken together, these data indicate that the distribution and implications of the bullfrog invasion in Grand Teton National Park are currently localized to a small area, so these bullfrogs should therefore be vulnerable to eradication.

Microbial community profiling of the Chinoike Jigoku (“Blood Pond Hell”) hot spring in Beppu, Japan: isolation and characterization of Fe(III)-reducing Sulfolobus sp. strain GA1

Chinoike Jigoku (“Blood Pond Hell”) is located in the hot spring town of Beppu on the southern island of Kyushu in Japan, and is the site of a red-colored acidic geothermal pond. This study aimed to investigate the microbial population composition in this extremely acidic environment and to isolate/characterize acidophilic microorganism with metal-reducing ability. Initially, PCR (using bacteria- and archaea-specific primers) of environmental DNA samples detected the presence of bacteria, but not archaea. This was followed by random sequencing analysis, confirming the presence of wide bacterial diversity at the site (123 clones derived from 18 bacterial and 1 archaeal genera), including those closely related to known autotrophic and heterotrophic acidophiles (Acidithiobacillus sp., Sulfobacillus sp., Alicyclobacillus sp.). Nevertheless, successive culture enrichment with Fe(III) under micro-aerobic conditions led to isolation of an unknown archaeal organism, Sulfolobus sp. GA1 (with 99.7% 16S rRNA gene sequence identity with Sulfolobus shibatae). Unlike many other known Sulfolobus spp., strain GA1 was shown to lack sulfur oxidation ability. Strain GA1 possessed only minor Fe(II) oxidation ability, but readily reduced Fe(III) during heterotrophic growth under micro-aerobic conditions. Strain GA1 was capable of reducing highly toxic Cr(VI) to less toxic/soluble Cr(III), demonstrating its potential utility in bioremediation of toxic metal species.

Introduced American Bullfrog Distribution and Diets in Grand Teton National Park

Introduced American Bullfrogs (Lithobates catesbeianus) have been present in Grand Teton National Park since approximately the 1950s, but little is known about their distribution and potential impacts. In this study, we surveyed the current bullfrog distribution and spatial overlap with sympatric native amphibians in the park, and characterized post-metamorphic bullfrog diets from July – September 2015. Despite surveys in multiple large rivers and floodplain habitats, we only documented bullfrogs in a geothermal pond and 5 km of stream channel immediately downstream of this pond. In these waters, bullfrogs overlapped with native amphibians at the downstream end of their distribution, and we did not document native amphibians in bullfrog stomach contents. Larger bullfrogs (SVL ≥ 96 mm) primarily consumed native rodents (especially meadow voles, Microtus pennsylvanicus), while smaller bullfrogs frequently consumed native invertebrates and less frequently consumed non-native invertebrates and fish. Taken together, these data indicate that the distribution and implications of the bullfrog invasion in Grand Teton National Park are currently localized to a small area, so these bullfrogs should therefore be vulnerable to eradication.

Estatus actual de conservación de seis especies de peces dulceacuícolas de la península de Baja California, México

The current distribution and conservation status of six native freshwater fishes of the Baja California peninsula (Entosphenus tridentatus, Oncorhynchus mykiss nelsoni, Fundulus lima, Cyprinodon macularius, Gasterosteus aculeatus and Gobiesox juniperoserrai), included in the Norma Oficial Mexicana-059-2010, were assessed on the basis of information generated during the study period of 2000–2014. Except for E. tridentatus in the Santo Domingo river drainage and G. juniperoserrai in the Las Pocitas-San Hilario drainage, most of the species were recorded in the hydrological basins sampled. Oncorhynchus mykiss nelsoni showed a significant population fluctuation in the San Rafael river in relation to the dynamics of the base flow and the forest fire events. Fundulus lima presented the probable extirpation from four drainages (San Javier, Bebelamas, San Luis, and Las Pocitas-San Hilario) that is contrasting with the finding of a new population in the Santa Cruz stream. Cyprinodon macularius in the most important remnant population in Baja California (cerro Prieto geothermal ponds) showed interannual fluctuations related with the level of flooding and availability of marginal habitats. Gasterosteus aculeatus showed a progressive population reduction in the southernmost distributional locality (mouth of El Rosario river), as well as the extirpation in the lower Santo Domingo river basin and its recent presence in the mouth of the Cantamar river. Gobiesox juniperoserrai, known only from the type locality is determined as extirpated.

Vallisneria spiralisandEgeria densa(Hydrocharitaceae) in arctic and subarctic Iceland

AbstractWe report the spread of two aquatic invasive plants, Vallisneria spiralis L. and Egeria densa Planch., into geothermal ponds in Iceland. These species are effective invaders due to their efficient dispersal, vegetative reproduction, high biomass production, and popularity in the aquarium trade. V. spiralis and E. densa were found in 2013 in a man-made pond near Husavik in northern Iceland. E. densa also occurs, at least since 2004, in southern Iceland, in Opnur Springs. Both species were confirmed by DNA sequencing. Our results indicate that V. spiralis and E. densa have established self-sustaining populations in Iceland, representing to date the northern-most confirmed occurrences of both species. These Icelandic populations extend the northern limit of E.densa and V. spiralis by at least 1000 km and, to our knowledge, are the first records of non-native invasive aquatic plants in the arctic and subarctic. Our study shows that geothermally heated water bodies can further facilitate the spread of ...

The fate of arsenic in a river acidified by volcanic activity and an acid thermal water and sedimentation mechanism.

The Shozu-gawa river, located in the Aomori Prefecture, northern Japan, is affected by volcanic activities and acid thermal waters. The river is unique because both solid arsenic (As; as orpiment, As2S3) and dissolved As are supplied to the river from the uppermost caldera lake (Usori-ko Lake) and thermal ponds. The watershed is an excellent site for investigating the fate of different As species in a fluvial system. Upstream sediments near the caldera lake and geothermal ponds are highly contaminated by orpiment. This solid phase is transported as far as the mouth of the river. On the other hand, dissolved As is removed from the river system by hydrous ferric oxides (HFOs); however, HFO formation and removal of dissolved As do not occur in the uppermost area of the watershed, resulting in further downstream transport of dissolved As. Consequently, upstream river sediments are enriched in orpiment, whereas As(v), which is associated with HFOs in river sediments, increases downstream. Furthermore, orpiment particles are larger, and possibly heavier, than those of HFO with sorbed As. Fractionation between different chemical states of As during transport in the Shozu-gawa river is facilitated not only by chemical processes (i.e., sorption of dissolved As by HFOs), but also by physical factors (i.e., gravity). In contrast to acid mine drainage (AMD), in some areas of the Shozu-gawa river, both solid forms of As (as sulfide minerals) and dissolved As are introduced into the aquatic system. Considering that the stabilities of sulfide minerals are rather different from those of oxides and hydroxides, river sediments contacted with thermal waters possibly act as sources of As under both aerobic and anaerobic conditions.

Debate bubbles over the origin of life

Could life have originated in geothermal ponds?

A Parachlorella kessleri (Trebouxiophyceae, Chlorophyta) strain from an extremely acidic geothermal pond in Argentina

Juárez Á.B., Vélez C.G., Iñiguez A.R., Martínez D.E., Rodríguez M.C., Vigna M.S. and Ríos de Molina M.C. 2011. A Parachlorella kessleri (Trebouxiophyceae, Chlorophyta) strain from an extremely acidic geothermal pond in Argentina. Phycologia 50: 413–421. DOI: 10.2216/10-79.1Acidic geothermal environments are rare and very few organisms can thrive in them. Chlorella or Chlorella-like species have been described in a variety of environments but their presence in extremely acidic waters have rarely been reported. A Chlorella-like alga (strain BAFC CA10) was isolated from Laguna Verde, a volcanic mesothermal acidic pond from northern Patagonia (Argentina). Applying a multimethod approach including microscopic, ultrastructural, chemical and phylogenetic analyses, the acidotolerant strain BAFC CA10 was identified as Parachlorella kessleri ( = Chlorella kessleri) on the basis of comparisons with the authentic strain SAG 211-11g. Our results confirmed the initial characterization of the Laguna Verde strain as C. kessleri, but since this species was transferred to the new genus Parachlorella, strain BAFC CA10 should be designated as P. kessleri. Histochemical staining and sugar composition of the cell-wall amorphous and fibrillar matrix, together with transmission electron microscopy of the cells, showed the distinctive characters of the species: (1) glucosamine was the exclusive component of the fibrillar cell wall; (2) rhamnose, galactose, glucose and xylose together with minor quantities of arabinose, mannose and fucose were present in the cell-wall hemicellulose matrix; (3) there was a single parietal chloroplast surrounding the entire cell with a small aperture (“mantel-shaped”); (4) there was one pyrenoid in the thickening of the chloroplast surrounded by two starch granules and bisected by two thylakoids; and (5) the cell wall was an electron-transparent homogeneous structure 60–80 nm thick. Phylogenetic analyses of concatenated small-subunit and internal transcribed sequence ribosomal DNA sequences of coccoid green algae within the Chlorella and the Parachlorella clades of the Chlorellaceae confirmed that strain BAFC CA10 is unequivocally related to the P. kessleri strains. Our results suggest that P. kessleri should be added to the list of species capable of adapting to live in extremely acidic environments.

Living in Vulcan's forge: Algal adaptation to stressful geothermal ponds on Vulcano Island (southern Italy) as a result of pre‐selective mutations

SUMMARYFour species of eukaryotic algae proliferate in the sulfureous, acidic (pH 3.1) water of the largest geothermal pond on Vulcano Island (southern Italy). Consequently, this pond constitutes a natural laboratory for analysis of adaptation by phytoplankters to extremely stressful conditions. To distinguish between the pre‐selective or post‐selective origin of adaptation processes allowing the existence of phytoplankters in the pond, a Luria‐Delbrück fluctuation test was carried out with the chlorophycean Dictyosphaerium chlorelloides and the cyanobacterium Microcystis aeruginosa, both isolated from non‐extreme waters; natural water from the Vulcano Island pond was used as selective factor. Preselective, resistant D. chlorelloides cells appeared with a frequency of 4.7 × 10−7 per cell per generation. We propose that the micro‐algae inhabiting this stressful pond could be the descendents of chance mutants that arrived in the past or are even arriving at the present. The genetic adaptation of D. chlorelloides to Vulcano waters could help to explain the survival of photosynthesizers in very stressful geothermal waters during the Neoproterozoic ‘snowball Earth’, a period when primary production collapsed in the biosphere. On the other hand, adaptation to these conditions was not observed in M. aeruginosa, suggesting that cyanobacteria may not be able to develop any kind of adaptation to Vulcano pond water.

D/H and 18O/16O fractionation factors in evaporation of water at 60 and 80.DEG.C.

The isotopic fractionation factors in evaporation of water at 60° and 80°C were determined from the isotopic ratios of water under steady-state balance between inflow and evaporation. The results at 60° and 80°C are 1.0501 ± 0.0029 and 1.0431 ± 0.0022 for H2O/HDO and 1.0176 ± 0.0010 and 1.0156 ± 0.0008 for H216O/H218O, respectively. Oyunuma, isotopically the heaviest geothermal pond in Japan, is enriched by 40.3‰ in D/H and by 16.5 ‰ in 18O/16O, respectively, relative to its meteoric inflow and may be a natural example of such steady-state evaporation pans.