The main purpose of BioAssess- the Biodiversity Assessment Tools Project- was to develop biodiversity indicators- or "biodiversity assessment tools" - that could be used to rapidly assess biodiversity. In addition, the BioAssess project aimed to measure the impacts on biodiversity of major land use changes in eight European countries.
The approach of the project was first to consider the major factors, particularly policy-related factors, influencing biodiversity in Europe. Thereafter, the project aimed to assess where the greatest needs for indicators of biodiversity exists through meetings and in an electronic conference with a wide range of stakeholders, leading to guidelines for the development of biodiversity assessment tools. From these guidelines, a series of indicators were proposed, including those that could be measured remotely from aerial photographs, and satellite and laser scanner images. The proposed biodiversity indicators were then be tested in large test sites representing different degrees of land use intensity - from forests to intensively managed agricultural areas. Six of these test sites were set up in Portugal, Spain, France, Switzerland, Hungary, Ireland, Finland and the UK. The biodiversity of the following groups of plants and animals were measured: soil-dwelling Collembola; earthworms and other soil macrofauna; ground beetles (Carabidae); plants, lichens, butterflies and birds. Thus the project was also designed to measure the impact of land-use change on several major components of biodiversity.
The BioAssess project succeeded in quantifying the impact of major land use changes in Europe on several major components of biodiversity, the first time this had been done using standardised protocols for different groups of plants and animals across Europe. It also showed how a "toolbox" of biodiversity indicators, including those derived from remote sensing, could be used to assess the impacts of policies on European biodiversity. The strengths and weaknesses of a range of potential biodiversity indicators were demonstrated. Several potentially useful indicators of above-ground biodiversity were identified, but these were poor indicators of soil biodiversity, and none of the soil biodiversity taxa studied were good indicators of other taxa in the soil. Soil biodiversity remains a major challenge to assess simply. Given the limited value of one or few taxa as indicators of all other components of biodiversity, a network of sites for the intensive observation of biodiversity is essential. Such a network would provide information on those components of biodiversity that extensive monitoring programmes do not address. A network of biodiversity observation sites where detailed information on biodiversity was regularly collected would also, amongst other things, permit the testing of indicators used in more extensive monitoring and, therefore, greatly increase the confidence in their application.