Individual study: Effect of agricultural practices on carabid populations
Hance T. & Gregoirewibo C. (1987) Effect of agricultural practices on carabid populations. Acta Phytopathologica Et Entomologica Hungarica, 22, 147-160
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Use organic rather than mineral fertilizers
A small study of seven cereal fields over one year in Belgium (Hance & Gregoirewibo 1987) found that organic manure increased the abundance and number of species of ground beetles (Carabidae). A field with a 60 t/ha application of organic manure (and organophosphorus insecticide) had significantly higher abundance (1,128 individuals) and number of species (20 species) than a field with no organic manure (and organochloride insecticide, 14 species). Ground beetle abundance was highest (1690 individuals) when, as well as applying organic manure (30 t/ha), green manure was applied in late summer and turned under the soil in early spring. Species diversity was highest with the highest concentration of organic manure (60 t/ha, 20 species). An application of aldicarb insecticide with organic manure did not affect the number of individuals, but slightly reduced the number of species. However, without manure, the insecticide resulted in a three-fold reduction in the number of individuals. Fields differed in organic manure (none, 30 t/ha, 60 t/ha) and insecticide (aldicarb, lindane, E-605). Ten pitfall traps were placed in a row in each field, 4 m apart and were sampled from April to September.