In the multispecies mesocosm experiment we test the overall performance, survival, reproduction and growth, of candidate species, in two different combinations, each replicated eight times, with and without the presence of a pesticide. These combinations are:
a.Six species including one earthworm, a mite and four species of springtails.
b.Six species including one enchytraeid, a mite and four species of springtails.
c.Control soil without test animals (only microbial performance)
The performance of each species combination will be evaluated in un-contaminated soil and in soil spiked with two different doses of cypermethrin mixed into the soil. These doses correspond to the EC50 and EC10 of the (most sensitive) species with known ecotoxicological response. Two samplings will be performed, i.e. after 4 and 8 weeks.Sub-samples of the test soil will be collected in each replicate and animals will be extracted and counted under a microscope.
Representative samples of the species and of the substrate will be used for Stable Isotope Fractionating analysis.
Endpoints include:
- Survival, reproduction, growth of
E. fetida- Microbial diversity (PFLA analysis)
- Structure, population dynamics, and trophic relationship of soil mesofauna
employing natural abundances of stable isotopes δ15N and δ13C.
- Fate of cypermethrin