Lake Hévíz
Encyclopedia
Lake Hévíz is located close to Hévíz
, Hungary
, near the western end of Lake Balaton
, five miles from Keszthely
.
It is the second largest thermal lake in the world (47,500 square metres in area). The flow of water is very strong and the lake is believed to be completely replenished each day.
The waters are reported to have curative effects, and there is a thriving health tourism industry in the area.
and chemical composition of the water, which is slightly radioactive and contains reduced sulfur
ic compounds as well as oxygen
in solution. Several species
so far can be found only in this lake.
Bacteria
is the dominant life form
in the lake; it is possible that this is a cause of the curative effect. Several taxon
s can be found here. Most common Cyanobacteria are filamentous blue-green algae (Oscillatoria princeps, O. tenuis, O. jasoruensis, O. chlorina, Spirulina
major). It is interesting to note that half of the blue species are thermophile
, stenoterm ones. There are two thermophile blue green alga species (Pseudanabaena papillaterminata, Pseudanabaena crassa) of which Lake Hévíz is the only Hungarian habitat.
Bacterial tektons are typical of the lake. The crater
is covered mostly by Thiothrix
sp. and Beggiatoa
sp. from a depth of 1.5 m to the opening of the springcave. These together with the bacterium species play an important role in the lake's sulfur cycle.
Actinomycetes (Streptomyces
sp., Micromonospora
sp.) are also worth mentioning. Micromonospora heviziensis
for instance, a very powerful protein and cellulose decomposer, can only be found here in the world. Microbispora amethystogenes on the other hand, which accumulates iodine
in its cells, is to be found in only few lakes in the world. Unfortunately this latter species has not been found in the lake since 1980s as a result of excessive mining
.
Changing environment affected other bacteria as well. Micromonospora carbonacea and M. chalcea was not detected in the 1990s. Actinomycetes communities have become dominated by Micromonospora purpureochromogenes, while M. heviziensis was suppressed. Antibiotics secreting Streptomyces are likely to be found.
Green algae
– especially Chlorella
sp. – are present all over the lake except for the springcave and its surroundings. Navicula
cryptocephala and Navicula
capitatoradiata are common diatoms in the lake. The biodiversity of the phytoplankton
is poor and its biomass
is low, thus the lake's trophic level
ranges from oligotrophic to mesotrophic.
There are two new species of Nematoda: Crocodolrylaimus thermalis and Neoactinolaimus tepidus. There can be found real rarities among Rotatorias as well (Epiphanes brachionus var. Spinosus, Lecane inermis), which are only present in warm waters. Jenő Ponyi has described the lake's primitive crustacean
s in detail. Also a unique Hydracarina acarus
is said to have found its habitat outside the fence surrounding the lake.
Hévíz
Hévíz is a town in Zala county, Hungary.- External links :* * * *...
, Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...
, near the western end of Lake Balaton
Lake Balaton
Lake Balaton is a freshwater lake in the Transdanubian region of Hungary. It is the largest lake in Central Europe, and one of its foremost tourist destinations. As Hungary is landlocked , Lake Balaton is often affectionately called the "Hungarian Sea"...
, five miles from Keszthely
Keszthely
Keszthely is a Hungarian city of 21,100 inhabitants located on the western shore of Lake Balaton. It's the second largest city by the lake after Siófok....
.
It is the second largest thermal lake in the world (47,500 square metres in area). The flow of water is very strong and the lake is believed to be completely replenished each day.
The waters are reported to have curative effects, and there is a thriving health tourism industry in the area.
Microscopic organisms of the lake
The fauna and flora are unique in Lake Hévíz due to the temperatureTemperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
and chemical composition of the water, which is slightly radioactive and contains reduced sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
ic compounds as well as oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
in solution. Several species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
so far can be found only in this lake.
Bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
is the dominant life form
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...
in the lake; it is possible that this is a cause of the curative effect. Several taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
s can be found here. Most common Cyanobacteria are filamentous blue-green algae (Oscillatoria princeps, O. tenuis, O. jasoruensis, O. chlorina, Spirulina
Spirulina
Spirulina may refer to:* Spirulina , a health-food supplement* Spirulina , a cyanobacterium group* Ochthephila spirulina, species of gastropod in the Hygromiidae family...
major). It is interesting to note that half of the blue species are thermophile
Thermophile
A thermophile is an organism — a type of extremophile — that thrives at relatively high temperatures, between 45 and 122 °C . Many thermophiles are archaea...
, stenoterm ones. There are two thermophile blue green alga species (Pseudanabaena papillaterminata, Pseudanabaena crassa) of which Lake Hévíz is the only Hungarian habitat.
Bacterial tektons are typical of the lake. The crater
Volcanic crater
A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...
is covered mostly by Thiothrix
Thiothrix
Thiothrix is a filamentous sulfur-oxidizing Gammaproteobacterium. It is said to be an obligately aerobic mixotroph and behaves similar to Beggiatoa....
sp. and Beggiatoa
Beggiatoa
Beggiatoa is a genus of bacteria in the order Thiotrichales. They are named after the Italian medic and botanist F.S. Beggiato. The organisms live in sulfur-rich environments...
sp. from a depth of 1.5 m to the opening of the springcave. These together with the bacterium species play an important role in the lake's sulfur cycle.
Actinomycetes (Streptomyces
Streptomyces
Streptomyces is the largest genus of Actinobacteria and the type genus of the family Streptomycetaceae. Over 500 species of Streptomyces bacteria have been described. As with the other Actinobacteria, streptomycetes are gram-positive, and have genomes with high guanine and cytosine content...
sp., Micromonospora
Micromonospora
Micromonospora is a genus of bacteria of the family Micromonosporaceae. They are gram-positive, spore-forming, generally aerobic, and form a branched mycelium; they occur as saprotrophic forms in soil and water...
sp.) are also worth mentioning. Micromonospora heviziensis
Micromonospora heviziensis
Micromonospora heviziensis is a very powerful protein and cellulose decomposer. This bacteria has only been found in Lake Hévíz .It has been described by C. Fernandez and Zs. Szabó in 1982....
for instance, a very powerful protein and cellulose decomposer, can only be found here in the world. Microbispora amethystogenes on the other hand, which accumulates iodine
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....
in its cells, is to be found in only few lakes in the world. Unfortunately this latter species has not been found in the lake since 1980s as a result of excessive mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
.
Changing environment affected other bacteria as well. Micromonospora carbonacea and M. chalcea was not detected in the 1990s. Actinomycetes communities have become dominated by Micromonospora purpureochromogenes, while M. heviziensis was suppressed. Antibiotics secreting Streptomyces are likely to be found.
Green algae
The green algae are the large group of algae from which the embryophytes emerged. As such, they form a paraphyletic group, although the group including both green algae and embryophytes is monophyletic...
– especially Chlorella
Chlorella
Chlorella is a genus of single-celled green algae, belonging to the phylum Chlorophyta. It is spherical in shape, about 2 to 10 μm in diameter, and is without flagella. Chlorella contains the green photosynthetic pigments chlorophyll-a and -b in its chloroplast...
sp. – are present all over the lake except for the springcave and its surroundings. Navicula
Navicula
Navicula is a genus of boat-shaped microbes that are a type of Phytoplankton or algae — primarily aquatic, eukaryotic, photosynthetic organisms, ranging in size from a single cell....
cryptocephala and Navicula
Navicula
Navicula is a genus of boat-shaped microbes that are a type of Phytoplankton or algae — primarily aquatic, eukaryotic, photosynthetic organisms, ranging in size from a single cell....
capitatoradiata are common diatoms in the lake. The biodiversity of the phytoplankton
Phytoplankton
Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words φυτόν , meaning "plant", and πλαγκτός , meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye...
is poor and its biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
is low, thus the lake's trophic level
Trophic level
The trophic level of an organism is the position it occupies in a food chain. The word trophic derives from the Greek τροφή referring to food or feeding. A food chain represents a succession of organisms that eat another organism and are, in turn, eaten themselves. The number of steps an organism...
ranges from oligotrophic to mesotrophic.
There are two new species of Nematoda: Crocodolrylaimus thermalis and Neoactinolaimus tepidus. There can be found real rarities among Rotatorias as well (Epiphanes brachionus var. Spinosus, Lecane inermis), which are only present in warm waters. Jenő Ponyi has described the lake's primitive crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s in detail. Also a unique Hydracarina acarus
Acarus
Acarus is a genus of mites in the family Acaridae.-Species:* Acarus ananas * Acarus beschkovi * Acarus bomiensis Wang, 1982* Acarus calcarabellus * Acarus chaetoxysilos Griffiths, 1970...
is said to have found its habitat outside the fence surrounding the lake.