Marisia - Maros Megyei Múzeum Évkönyve 32-34. (2014)
Zoology
Diversity of the beetle (Coleoptera) fauna from rapeseed and adjacent forest strip (Sadaclia, Republic ofMoldova) more diverse than rapeseed crop. Both curves are rising and do not yet reach a flat progression, which means that the beetle community has not been recorded completely. Fig. 2: Rarefaction curves for rapeseed and adjacent forest strip beetle cenoses (Sadaclia) Knowledge of beetle faunal assemblages in ecosystems, their trophic preferences and the ratio between groups is very important, because it can provide useful information on the ecological situation of the ecosystem and its functioning. The revealed beetle community from rapeseed crop was mainly composed by phytophagous (21 species), followed by coprophagous (9), mixophagous (5), saprophagous (3), necrophagous and predators (by 1). Regarding forest strip, beetle community was represented by 17 phytophagous species, 8 coprophagous, 4 mixophagous, 3 predators, 3 necrophagous and 2 saprophagous. Both ecosystems are populated primarily by phytophagous beetles, among them are known to cause serious damages to rapeseed species Phyllotreta nigripes, Epicometis hirta and Psylliodes chrysocephalus. The number of specimens collected is not alarming at present especially for last two species, but a careful monitoring of adult activity may be required. It is very important to know the status of predatory populations in agricultural ecosystems and to increase their potential as biological control agents. Only one predator species highlighted for rapeseed crop and other three for forest strip with a low effective number show that ecosystems are trophically unbalanced being anthropogenic affected. Also, a high number of coprophagous beetles caught from forest strip indicate the presence of livestock (cattle and sheep) and degradation of this ecosystem through overgrazing. Soil processing of the agricultural crops has strong influences on insect complexes, during this period they find refuge to the edge of fields and adjacent forest belts and return back to the field after emergence of the plants when there is enough food. Usually, the fields near the forest strip present a greater fauna diversity, but in this study it was not confirmed. 121
