Epsilon Archive for Student Projects

Abstract

In this study the condition and fecundity of a genus of the polyphagous predator, Bembidion. is investigated in respect to landscape complexity and farming practice. The beetles where collected during 1999 from five pairs of conventional and organic farms in central east Sweden (in the area around Uppsala). The farms within each pair were situated close to each other and had similar size and landscape structure. The condition was measured as the percent fat in Bembidion captured during spring and fecundity was studied in laboratory were the amount of eggs were counted and the egg volume measured. On organic farms there were correlations between number of eggs and crop diversity and between eggs and landscape heterogeneity. On the conventional farms there were correlations between fat and landscape heterogeneity and also between fat and perimeter-to-area ratio. There was also a correlation between egg volume and perimeter-to-area ratio on conventional farms. The results indicate that it is possible to improve the condition and fecundity of Bembidion, and thereby increase the predation of pest aphids.