Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Journal of Ecological Engineering

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Bacterial ACC Deaminase Activity in Promoting Plant Growth on Areas Contaminated with Heavy Metals

Grobelak A., Kokot P., Świątek J., Jaskulak M., Rorat A.

Journal of Ecological Engineering

2018

Vol. 19, nr 5

150--157

The objective of this study was to explore the possible improvement of plant growth using the activity of the bacterial enzyme ACC (1-aminocyclopropane-1-carboxylate) deaminase (endophytes and rhizobacteria). The beneficial effect of ACC deaminase activity was tested on the plants growing under stress conditions (high concentrations of heavy metals: cadmium, lead, zinc in the soil). The bacteria were isolated from three plants species: Festuca rubra L., Agrostis capillaris L., Arabidopsis thaliana L. Heynh, acquired from the area contaminated with heavy metals. The strains with the highest ACC deaminase activity were used to prepare a bacterial consortium and inoculate the plants. It has been shown that inoculation of plants with ACC producing bacteria has a positive effect on their growth under stress conditions. The bacterial entophytes strains showed a higher activity of ACC deaminase, which resulted in a higher biomass growth of inoculated plants. The PGPB bacteria may limit the toxicity of harmful ions and thus the increase the adaptive properties of plants. Moreover, it was discovered that the bacteria mainly belonging to genus Bacillus and Pseudomonas had the highest ACC deaminase activity in the environment contaminated with multiple heavy metals. The use of selected microorganisms and plants will provide results in an increasing efficiency of phytoremediation.

Vermicomposting as an Alternative Way of Biodegradable Waste Management For Small Municipalities

Sosnecka A., Kacprzak M., Rorat A.

Journal of Ecological Engineering

2016

Vol. 17, nr 3

91--96

The aim of the study was to assess the usefulness of vermicomposting as a method of bioconversion of organic wastes, inter alia, sewage sludge, biodegradable fraction of municipal solid wastes and green wastes. Vermicomposting is a biological process in which earthworms are employed to cooperate with microorganisms in order to convert organic wastes into a valuable product. It is considered as a relatively low cost and environmentally-friendly method of waste treatment. Nevertheless, as each biotechnology, the process is limited to some physical, chemical and biological parameters. In this study, sewage sludge coming from medium-sized wastewater treatment plant was mixed with mown grass, sawdust and organic fraction of municipal wastes and vermicomposted for 5 weeks with Eisenia fetida and Eisenia andrei as main actors. The scope of the research was to 1)assess the influence of E. fetida and E.andrei composting earthworms on the physical and chemical properties of the product; 2) changes of concentration of selected heavy metals and their available forms in compost during the process, 3) the effects of substrates on earthworms survival and reproduction. Selected earthworm species had shown a high tolerance to the contaminants present in sewage sludge and a positive impact on the quality of the product was noted. Vermicomposting enhances decomposition of organic matter, leads to decrease in C/N ratio and pH, and changes the availability of some heavy metals and its total content in substratum. Experimental medium led earthworms to increase body weight due to the presence of large amount of organic matter, while the reproduction was importantly reduced. Vermicomposting can be considered as a method of treatment of solid wastes, mainly in the case of small municipalities.