Improving the assessment and monitoring of forest biodiversity

Purpose - This paper aims to present a general analysis and overview of forest biodiversity, emphasising the three main components (structure, composition, function) related to biodiversity. Following this theoretical consideration of forest biodiversity the current proposal of the European Environment Agency for biodiversity indicators is presented as a table with the application to forests identified and the direct/indirect nature of the indicator also indicated. Design/methodology/approach - The biodiversity of forests is determined by a number of overall large-scale factors that intimately affect the individual components of biodiversity. A more specific and direct measurement of forest biodiversity is presented with data assessed by the Fungib programme to provide a set of biodiversity indices that can be used to: create biodiversity baselines; compare sites; and follow biodiversity changes through time, all with the possibility of determining significance of change statistically. An example of data derived from a macrofungal survey is presented as an example of how this methodology can be adapted to many groups of organisms. Finally, a further example of using biodiversity quality data to understand changes in biodiversity is presented comparing butterfly biodiversity quality with nitrogen deposition. Findings - This paper shows how an example of function (nitrogen deposition) has affected an element of composition (butterfly biodiversity). This has been made possible by the use of a rational sampling methodology (TRIM) used over a number of years. This metadata analysis of butterfly survey data shows clearly that changes in the butterfly biodiversity quality would have been missed if the normal approach of equating biodiversity with species richness had been adopted. In this example nitrogen-sensitive species loss was compensated by nitrophilic species gain. Originality/value - Such a methodology, therefore, has much to recommend it and it has been shown to be applicable to a wide range of organisms from bryophytes to beetles. For forest biodiversity monitoring the adoption of this kind of rationale will hopefully yield far greater information to the scientific community and policy makers for little extra effort.