Comparative Effects of Clump-Based and Traditional Selective Harvesting on Understory Biodiversity in Sympodial Bamboo Forests.

To improve the efficiency and reduce the cost of traditional sympodial bamboo harvesting, this study evaluated the effects of four harvesting intensities-selective harvesting, one-third clump, one-half clump, and complete clump harvesting-on understory plant diversity in pure stands over a five-year recovery period. A total of 36 species were recorded in the first year, increasing to 71 in the third year and stabilizing at 74 species by year five. Understory α-diversity showed an increasing trend followed by a decline. In the early recovery stage, species diversity was significantly correlated with soil chemical properties ( < 0.05), but no significant correlation was observed in the later stage. Fuzzy membership function analysis indicated that the 1/2 clump harvesting treatment outperformed others, ranking as follows: 1/2 clump > 1/3 clump > selective > complete clump harvesting. These results suggest that 1/2 clump harvesting is optimal for promoting understory vegetation growth, but its positive effects on biodiversity are time-limited, with the plant community showing a trend toward simplification over time.