Organic farming provides greater species richness already in the first year after conversion

Organic farming has, by not using chemical pesticides and fertilizers, been used as a way to counteract the loss of biodiversity in the modern agricultural landscape.

However, very little is known about how quickly biodiversity responds to such a change in the agricultural system.

By measuring the number of plants and butterflies on conventional farms compared with organic farms, the researchers at SLU and Lund were able to estimate whether and how quickly these organisms react to the conversion to organic farming.

The species diversity of both plants and butterflies was higher the year after. The number of butterflies also continued to increase continuously with time after conversion. They were on average 100 percent more on the farms that have been organic for 25 years compared to the recently converted.

The results were presented in the latest issue of the Journal of Applied Ecology: Assessing the effect of the time since transition to organic farming on plants and butterflies.

The researchers behind the study: Dennis Jonason (SLU), Georg K.S. Andersson (LU), Erik Öckinger (SLU), Maj Rundlöf (LU), Henrik G. Smith (LU) and Jan Bengtsson (SLU).