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Mud volcanoes represent related formations, which have structural and functional similarities and can be found on land and in undersea zones. Mud volcanoes are different from other geological forms by their capacity to expell different forms of materia (gas, water and sediment) and the relatively violent kind of performing it. The sizes of mud volcanoes go from very small up to kilometers, shapes go from caldera to cones and they can exhibit from almost inaction to rising columns of fire. The mud consistency also differ, from aqueous to high viscosity, and the emissions can involve high quantities of methane and carbon dioxide. Volcanoes releasing thermogenic methane have the reservoirs at profound depths, while the ones with biogenic gas have the reservoirs no deeper than 2000 m. This review provides informations regarding genesis and distribution of mud volcanoes, and also the description of morphology and topology of the mud volcano and the adjacent area. The classification types are set out, as well as the phenomenon of mud volcanism. In the end the expelled products are identified, different post-genetic processes being established, thus it can be assessed if the expelled products are of thermogenic or biogenic nature. Microbiological processes within mud volcanoes were also described from anaerobic oxidations, aerobic oxidations to methanogenesis. Both, Archaea and Bacteria are involved in these prcesses. Common patterns were identified for mud volcanoes which harbour a large array of bacterial and archaeal phyla. Mud volcanoes have a consistent share in the natural gass emissions into the atmosphere. They have a global occurance and give us a different way to investigate the Earth's interior, yet are largely unresearched. [ABSTRACT FROM AUTHOR]

Poly-β-hydroxybutyrates producing Azotobacter strains were isolated from zones with heterogenous environmental conditions from Romanian Carpathians and Transylvanian Plateau: alpine, karstic and xeric meadows and flood plain. These strains were grown on Azotobacter specific media with different carbon sources (mannitol and sucrose). In order to assess the cell viability the following parameters were determined: optical density - by spectrophotometry; viability - by measuring ATP quantity based on bioluminescence luciferase reaction but also using plate culture method of numbering the viable cells, proteins concentration - by Lowry method. The viability assessed by ATP measuring was checked by numbering the viable cells from Petri dishes stained with methylene blue. [ABSTRACT FROM AUTHOR]

Sulphur is the fourth major essential nutrient element, after nitrogen, phosphorus and potassium, involved in biogeochemical cycles in nature. Sulphur is essential in all organisms because it is an integral part of major metabolic compounds, such as amino acids (methionine and cysteine), and it is an active component of numerous co-factors and prosthetic groups (Fe-S clusters, sulpholipids, glucosinolates, vitamins, etc), which are involved in metabolic processes of organisms. Medical research appears to confirm the validity of the use of sulphurous spring waters as therapeutical and preventive remedies for a large variety of diseases. In order to evaluate the quality of sulphurous water, samples have been taken of the Sulphurous Springs in Jibou. The objectives of this study were to determine physical and chemical properties (pH, electrical conductivity, salinity, redox potential) of some sulphurous water samples of Jibou area, and also to determine the microbiota involved in S biogeochemical cycle. The physical analysis showed that the sulphurous water of Jibou falls within the very weakly acidic reaction class, and the salinity was 0.2% in all samples. The aerobic heterotrophic bacteria show a maximum value in the sample 4 (2630x103 bacteria/ml). The microbial sulphurous community was detected in all water samples. This information should improve our understanding on adaptation mechanisms of bacteria involved in the sulphur cycle in correlation with physical-chemical parameters. [ABSTRACT FROM AUTHOR]

Salty soil samples from three zones of Cojocna (Cluj county, Romania) have been investigated physico-chemically and enzymologically. Rizosphere of some halophytes were investigated in order to assess saline stress on bacterial enzyme activities and halophytes adaptation mechanisms to enhanced salt content. Several physico-chemical parameters of salty soil were determinated: pH, conductivity and different mineral ion contents. Changeful bacterial enzymatic activities and mineral ion composition were detected according to soil salt content. Reduced values of all enzymatic activities were detected. Based on the studied enzyme activities the enzymatic indicators of soil quality (EISQ) were calculated. The EISQ values were low, between EISQ = 0.201 and 0.236. In the sudied salty area, only a few halophyte species were observed and identified, the most common are: Salicornia herbacea, Puccinellia distans, Artemisia santonica, Limonium gmelinii and Salsola soda. All three salty zones were classified as sodic and saline-sodic soils. [ABSTRACT FROM AUTHOR]