XVI International Botanical Congess
Particularly in Europe, frequent changes of landscape usage and the splitting of continuous woodlands into smaller spatially isolated remnants have led to extremely fragmented woodland areas causing a high degree of isolation between plant populations. Nevertheless, some woodlands have survived since at least 200 years ago. They are defined as ancient woodlands. We present results of floristic studies in northern Germany. Therefore most of the woodland herbaceous species are significantly associated to (semi-) natural ancient woodlands. A high percentage of these species is assumed to disperse their seeds only over short distances. With these species, the hypothesis is put forward that the low ability of seed dispersal is a predominant factor preventing colonization of recent, especially isolated woodlands. Concepts are given for inferring seed dispersal from spatial genetic patterns as assessed by maternally inherited DNA markers. First results are presented.