IPM is the application of a range of practices to reduce the impact of pests and reliance on chemicals. Biodiversity has been described as integral to IPM. This report provides an assessment of the evidence to help understand which IPM techniques deliver the most benefits for biodiversity, the opportunities for biodiversity enhancement and circumstances where there is a potential for negative impacts on biodiversity.
A wide range of references have been consulted, but this was not exhaustive. The first part of the review summarises seven IPM projects done between 1981 and 2005. The second part is a review of reports concerning the effect of IPM on biodiversity. Most studies tested or observed effects on species abundance rather than biodiversity. IPM techniques were covered in the arable (13), outdoor horticulture (9) and grassland (10) sectors. The biodiversity categories covered were: birds; mammals; fish; amphibians; reptile; arthropods, annelids, molluscs; soil micro, meso- and macro-fauna; non-target plants and protected species.
The reporting covered both the benefits and negatives to biodiversity. The greatest percentage of references concerning biodiversity covered arthropods, annelids and molluscs, followed by non-target plants and birds.
Most techniques had a positive impact on biodiversity with crop rotation, field margins, cover crops and companion crops having the most positive references. The techniques that had the greatest negative impact on biodiversity were cultivations, harvesting and mowing and topping.
The review has shown that there is an extensive amount of evidence on the effects of IPM on species abundance, but there are many knowledge gaps.