We used a relascope (horizontal point sampling) approach for tree selection and direct basal area (BA) estimation (Bitterlich, 1984). This method allows quick sampling of many plots, with
minimal accuracy differences compared with fixed-area plots (Piqué et al., 2011). During the 360 sweep from each plot-centre, a tree was counted as ‘‘in’’ if it was wider than the relascope notch; borderline trees were checked with their dbh and distance from the plot-centre. The BA of each plot was calculated by multiplying the number of ‘‘in’’ trees with the BAF (Bitterlich, 1984). Correction was later done for slope. Starting with the first plot, in every fifth
plot after that we measured the diameter at breast height (dbh at 1.30 m) of each ‘‘in’’ tree. In these plots (referred to as ‘‘detailed-plots’’), we also used a checklist to record whether branches or stems had been cut-off trees (termed ‘‘lopping’’), whether the tree was alive and whether it had been planted. Sub-plots of 5 m diameter were used to measure stumps (<1.30 m in height) and count saplings smaller than 2.5 cm dbh and between 2.6 and 5 cm, but taller than 1.30 m and seedlings shorter than 1.3 m. We scored each plot for signs of human activity such as trails and trampling, agriculture, fire (as evidenced from charring of stems and stumps), pit-sawing, charcoal burning (pits), pole cutting (cut stems) and other signs of wood harvesting. The collection of naturally fallen firewood does not leave obvious signs, but signs of wood splitting were found as waste or piles of split stems drying away from trails. Scores were assigned on a scale of 2 (absent and present) or 3 (absent, present, and severe) depending on the indicator (Table 3). Additionally, we recorded the location of any charcoal pits or signs of pit-sawing encountered while moving between plots (Fig. 1).
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