| Abstrakt: |
Earthworms (Oligochaeta: Lumbricidae) are typical representatives of the functional group of ecosystem engineers. They actively participate in formation and stabilisation of soil fertility through their effect on its buffer capacity. Buffer capacity defines in many aspects soil potential, supports immobilisation and mobilisation of certain elements of fertility, and first of all mineral elements essential for plants, productive moisture, heat energy of soil, gas composition of soil air, etc. Park soils within megapolises territory are megapolises' integral components, and this feature defines conditions of growth and development for green plants. To evaluate the contribution of earthworm coprolites into acidic-base (pH) buffer capacity of two categories of soil within the city, i.e., urban soils and urban grounds (urbanozems) of the park zones within the plots planted with Norway maple (Acer platanoides L.) trees on the territory of two parks Zeleny Gai and Pisarzhevsky Park (city Dnipro, Ukraine), soil and coprolites samples were collected. Buffer capacity of coprolites and anthropogenically transformed soils (urban soils) was evaluated according to the Arrhenius method after "a buffer area". It was established that acid-base buffer capacity of coprolites (earthworm excretes), which are new formations of zoogenic origin in soil, was statistically significantly higher than for the initial type soil within city parks. For urban soil with the upper humified layer of calcic chernozem within the acidic diapason of external load, it was 22.9% higher, which, on average, accordingly was 22.9 and 18.7 convectional units; within alkaline, it was 18.4% higher and was, accordingly, 24.2 and 20.4 convectional units; and in sum (acidic-alkaline), it was 20.6% higher and was 47.1 and 39.1 convectional units. For urban ground (urbanozem) within the acidic diapason of external load, it was 44.9% higher and acidic-alkaline buffering capacity, on average, accordingly, was 25.5 and 17.6 convectional units; in sum (acidic-alkaline), it was 20.6% higher and was 42.8 and 35.4 convectional units, accordingly. Thus, soil saprophages, such as earthworms, in the conditions of magapolises in the recreation zones within the territories of city parks' green plantations are one of the natural factors of ecological rehabilitation of urban soils. This, in general, improves the ecological state of green plantations on urban soils within park areas and recreation zone edaphotope revitalisation as well as supports optimisation of human living and recreation environment. [ABSTRACT FROM AUTHOR] |
