COMPARISON OF 2 METHODS FOR ESTIMATING THE SIZE OF THE VIABLE SEED BANK OF 2 PLANT-COMMUNITIES IN THE STRANDVELD OF THE WEST-COAST, SOUTH-AFRICA

Due to the important role of the soil seed bank in revegetation studie s, the viable seed content of two sites at Brand se Baai (Strandveld o f the west coast, South Africa) was estimated by means of the emergenc e and flotation methods. Most of the seeds were found to be small and only 'apparent viability' was determined after flotation had been comp leted. The average size of the seed bank different significantly betwe en the two sites and decreased with increased sampling depth. The flot ation method yielded a significantly larger number of seeds per square metre than the emergence method. A combination of these two methods i s, therefore, recommended for estimating the size of to germinable see d bank of the Brand se Baai area, due to the problems inherent to each method.