By Helen Briggs
BBC Environment correspondent
Organic farms act as a refuge for wild plants, offsetting the loss of biodiversity on conventional farms, a study suggests.
Fields around organic farms have more types of wild plants, providing benefits for wildlife, say scientists.
The research is likely to fuel the debate over the environmental benefits of organic farming.
Studies suggest that organic farming produces lower yields than conventional methods but harbours more wildlife.
The new study, by researchers at the University of Swansea and institutes in France, looked at fields sowed with winter wheat in the region of Poitou-Charente.
They found that organic farming led to higher weed diversity on surrounding conventionally farmed fields.
"Wild plants are important for birds, bees and other farmland species," said Dr Luca Borger of the department of biosciences at Swansea University.
"Organic farming has advantages in maintaining these, but 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."
Food security
Farmland provides essential habitat for many animals but intensification of agriculture has led to a loss of biodiversity.
However, in order to provide the extra food needed by the bigger human population of the future, without destroying forests and wetlands, farming needs to be made more intensive.
Supporters of organic farming say the method could be a potential compromise between meeting food security needs and providing habitat for bees, birds and other wildlife.
The researchers say land-sharing between organic farms and non-organic farms could have benefits for both crop production and biodiversity.
This theory needs to be tested in follow-up studies, they say.
The study is published in the journal, Proceedings of the Royal Society of London B- Biological Sciences.
Source: BBC