Flora and Fauna Changes During Conversion from Conventional to Organic Farming

Preface and acknowledgements

In a project 1996-2000 the possible effects on flora and fauna of reducing pesticide dosages experimentally at large scale were investigated at five large farms in Denmark (Esbjerg & Petersen 2002). During the last field season (1999) the owner of one farm decided to convert from conventional to organic production. This decision opened a rare research opportunity of possible interest for environmental protection: To study the immediate influence of conversion on flora and fauna. Other investigations have demonstrated the value of organic farming in terms of richer nature but always on farms which had been organic for a number of years. In the present case the established knowledge of plants, arthropods and birds during three preceding years provided an excellent background for a study of possible changes in biodiversity the first two years after the conversion starting 2000.

On the above background the present project was planned and applied for to the Danish Ministry of the Environment which allocated the necessary funding. Like the preceding project – afterwards called the conventional period – also this project included three main areas, botany, entomology (arthropods), and ornithology.

The project was initiated while treatment of sampling data from the conventional period was still ongoing. The treatment of data and statistical analyses with comparisons of the two periods 1997-98-99 (conventional) and 2000-2001 (organic) were finalized in 2001.

The partners of the project were:

Botanical aspects: Dept. of Physiological Ecology, Botanical Institute, University of Copenhagen (Anne-Mette M. Jensen and Ib Johnsen)

Entomological aspects: Zoology Section, Dept. of Ecology, Royal Veterinary and Agricultural University (Peter Esbjerg and Søren Navntoft)

Ornithological aspects: Ornis Consult A/S (now: Hedeselskabet Miljø og Energi as) (Bo Svenning Petersen)

The practical execution of the project would have been impossible without the understanding and generosity of the landowner of Oremandsgård Estate, Daniel Hage and the good collaboration of the Manager, Mogens Tved. They are cordially thanked for their collaboration.

Furthermore thanks are due to the members of the steering committee of the project:

Jørn Kirkegaard and Kaj Juhl Madsen, Danish Environmental Protection Agency
Niels Elmegaard, National Environmental Research Institute, Silkeborg
Chris Topping, National Environmental Research Institute, Kalø
Jørgen Jakobsen, Danish Institute of Agricultural Sciences, Flakkebjerg
Poul Henning Petersen, Danish Agricultural Advisory Centre.