Floristic change is interpreted by reference to the functional characteristics of the species present, and utilises an autecological database (see Hodgson et al., 1995). Briefly, the ecological characteristics of declining species are compared to see if trends canbe identified and attributed to changes in grazing, succession, etc. For example, if annual species that requiremoist conditions appear to be declining, this could be linked to periods of drought or increased drainage.FIBS analyses should be carried out on:1. the characteristics of the initial vegetation (for reference, for deciding frequency of monitoring and for comparing different sites);2. a comparison of the characteristics of ‘increased’ and ‘decreased’ species (the main part of the analysis for detecting and interpreting floristic change); and3. a comparison of the characteristics of the different strips or sub-plots (to examine whether the site is heterogeneous and whether floristic change is occurring across the whole site or is restricted to certain areas).
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