Orimulsijos poveikis sliekų populiacijai ir biomasei
Abstract
Investigation of earthworms, Eisenia foetida (Californian line), survival and biornass changes in the soil polluted with orimulsion was carried out under laboratory conditions. The investigation was carried out in plastic buckets (capacity of 7 liters) with 3.5 kg of orimulsion contaminated soil which 25% of was the substratum of organisms. An experiment was made under specific-conditions, i. e. at 20—220C temperature and around 80% of humidity. During the experiment pH of the soil was controlled. Every tenth day the soil was aerated. In order to assess different orimulsion doses the impact of on earthworms, buckets were filled with 10 g/kg, 15 g/kg, 25 gkg and 50g/kg of orimulsion correspondingly. An orimulsion impact on the survival and reproduction of earthworms was registered after 4, 7, 10 15, 25 days from the beginning of the experiment. The obtained data showed a direct relationship between the orimulsion concentration in the soil and the sun'ival and changes of earthworm population. When the orimulsion dose was 10 gkg, the population of earthworms decreased by around 1.2%. When the dose was the biggest the population of earthworms decreased by 17-18%. The investigation results showed that when the orimulsion doses in the soil are low (10 g/kg). a negative injhtence on earthworms was obsen>ed only during the first Jew days. The greatest effect on the biornass of earthworm was registered when the concentration of orimulsion was 50 g/kg. In this case the biornass of population decreased by around 40 g. According to our results we can confirm that the negative orimulsion effect on the soil fauna (earthworms) is less than that of crude oil.