Pollen productivity estimates for a pine woodland in eastern Scotland: The influence of sampling design and vegetation patterning

article i nfo Quantitative vegetation reconstruction models have been developed to allow more faithful accounts of changes in vegetation structure to be attained. Widespread application of these models is encouraged, how- ever for this to be realised necessary parameter values, such as pollen productivity estimates require further investigation. This study shows results of tests undertaken to detect the influence of a homogenous vegeta- tion structure and sampling strategy upon the calculation of PPEs from contemporary data. Using a collection of contemporary moss samples, sub-groups were created using defined sampling strategies (random or sys- tematic) and nearest neighbour distance thresholds to investigate the influence of these conditions upon PPE generation. Results suggest that a random sampling strategy achieves the most reliable values, but using a systematic strategy is possible. Furthermore, in areas where vegetation patterning is non-stationary, a large degree of variation is incorporated into the values obtained, and the use of quantitative models in such situations could be problematic.