New research suggests that organic farming increases the biodiversity in agricultural landscapes. A study published in the journal Proceedings of the Royal Society of London B- Biological Sciences shows that organic fields have a higher diversity of wild plants, offsetting the loss of biodiversity on surrounding conventional farms. The researchers at Swansea University compared organic and conventionally farmed fields sowed with winter wheat in the Poitou-Charente region of France. They found that the presence of organic farming in the landscape led to higher local weed biodiversity also for conventionally farmed fields, and even reached a similar biodiversity level to organic fields in field margins. While weeds may induce crop yield loss, they represent the basic trophic component in agricultural food webs. “Wild plants are important for birds, bees and other farmland species. Organic farming has advantages in maintaining these,” said Dr Luca Borger of the Department of Biosciences at Swansea University. However, the intensification of agriculture has led to a loss of biodiversity in agricultural landscapes. Wild plants are strongly affected by the application of herbicides and fertilisation. As organically farmed fields in general harbour more insect-pollinated plants, forbs and rare or threatened weeds, their presence in the landscape could mitigate the negative effects of conventional agricultural management. „Even a mixture of organic and non-organic farming in an area can help maintain this biodiversity. Even only 25% of fields being organically farmed can make a difference”, said Dr Luca Borger. Land-sharing between organic and non-organic farms could have benefits for both crop production and biodiversity. According to the researchers, very few studies have investigated how the biodiversity of a field is affected by the presence or density of organically farmed fields around them. They said further studies are needed but they hope their research will contribute to the debate on the environmental benefits of organic farming over conventional methods. (ab)