FINE-ROOT GROWTH IN BEECH (FAGUS-SYLVATICA) FOREST GAPS

The purpose of the study was to investigate fine-root growth in gaps c reated for beech (Fagus sylvatica L.) regeneration. Fine-root growth w as measured using the ingrowth core technique. Measurements were carri ed out in gaps 30 m in diameter, which were either untreated or treate d with lime, and in a mature beech stand. Ingrowth core experiments sh owed that growth of beech fine roots in gap centres was negligible dur ing the 2nd and 3rd year after gap creation, indicating that although fine roots from stumps stayed alive long after trees were cut, they di d not grow. It also indicated that trees surrounding gaps did not effe ctively grow fine roots that reached 10 m into the gap centre. At the edge of unlimed gaps (5 m away from the stems), fine-root growth was o ne-third that of the mature stand. In the stand the amount of live fin e roots in ingrowth cores (390 g . m(-2)) had attained the standing cr op level after 16 months. In limed gaps, where herbaceous vegetation h ad established, herbaceous root growth was 800-970 g . m(-2) after 16 months. Neither fine-root growth nor aboveground biomass of herbaceous plants was substantial in untreated gaps. The slow recovery of biomas s production in unlimed gaps showed that the resistance of this beech forest to nutrient losses following disturbance is low.