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Microbial activity of different earthworms species castsтезисы доклада
- Авторы: Kostina Natalya V., Kozlova Juliya E., Kuznetsova Tatyana A.
- Сборник: Book of Abstracts of 9th International Soil Science Congress on “The Soul of Soil and Civilization”
- Том: 1
- Тезисы
- Год издания: 2014
- Место издания: Side, Turkey
- Первая страница: 56
- Последняя страница: 56
- Аннотация: The indicators of biological activity (respiration, methanogenesis, nitrogen fixation, denitrification, the size and structure of the microbial complex) and functional biodiversity of microbial communities in casts of two earthworms species and sod-podzolic medium-loam soils were evaluated in the model experiment. It is shown that earthworms of different ecological trophic groups (soil-litter species Lumbricus rubellus and typically soil Arorrectodea rosea) influence the indexes of soil biological activity in different degrees. The emissions of carbon dioxide, nitrous oxide, and nitrogen fixing activity in soil and casts inhabited by worms were higher than in a control soil. However, nitrogen fixation takes place more rapidly in L. rubellus casts, and denitrification in A. rosea casts. The length of the fungal mycelium significantly decreases and bacteria, including nitrogen-fixing forms, growth in the casts of L. rubellus compared with a control soil. The length of fungal mycelium in A. rosea casts on the contrary increases with time. The evaluation of the functional diversity of microbial communities in the casts of two earthworms’ species and control soil using multisubstrate test (MST) showed their significant difference not only between the control soil and casts, but also between casts of different earthworms species. The high indexes of consumed substrates, diversity and evenness, as well as very high indexes of the metabolic activity and the stability of microbial systems were determined in A. rosea casts, and in casts L. rubellus these rates were significantly lower. Assessment of microbial communities stability based on the analyses of rank distributions of test substrates consumption showed very high stability of the microbial community in A. rosea casts (d = 0,045) and very low - in L. rubellus casts (d = 1,32). So high values of the “d” index indicates significant changes in the functional soil microbial system cohesiveness and of its destabilization. Apparently, there is a significant change in the soil microbial community structure that leads to an increase in the number of members of individual microorganisms taxons in L. rubellus casts. We noted an increase in the number of bacteria and a significant reduction of the fungal mycelium length in casts of this earthworm species.
- Добавил в систему: Костина Наталья Викторовна