Recent spatial development of Svalbard strandflat vegetation over a period of 31 years

Vegetation succession was analysed at the forefields of two glaciers in Svalbard over an interval of 31 years (1975-2006). In 1975, 85 sampling sites were positioned along transects extending from the coastline to the glacier fronts: botanical observations were made at each sampling site. This protocol allowed us to carry out new observations in 2006 under the same conditions. Thus, it was possible to undertake a botanical assessment of species and taxa, and to see how the vegetation has changed with reference to a typology established by coupling correspondence analysis and ascending hierarchical classification. Vegetation succession at the sampling sites was also measured by using vectors positioned in the multidimensional space of correspondence analysis. In this way, the changes over the interval between seven vegetation types were plotted and mapped, and the colonization process was calibrated and dated against a series of reference stages, mainly since the end of the Little Ice Age.