Gap characteristics and replacement patterns in the Knysna Forest, South Africa

Abstract

Abstract. We investigated gap formation and gap replacement in the Knysna Forest. Most (70 %) trees died standing, most gaps were small (median gap size of 35 m 2 ; Gap diameter/Canopy height ratio of 0.24) and were formed by a single dead individual. No large differences were found among the more common species in terms of the size of gaps they created when they died or in the size of gaps they colonised. This is probably because the more common species are shade tolerant and they established before the gaps were formed. Regenerating individuals were almost never found on root mounds in pits or on logs. There were no indications of specific replacement patterns. In contrast, random replacement appears to be the dominant pattern for the more common species. Overall successional patterns suggest that the forest is relatively stable. We conclude that the gaps/non‐gaps paradigm is not as useful as a lottery paradigm for explaining gap dynamics in the Knysna Forest.