Change in plant species composition on powerline corridor: a case study

Area of Science:

• Ecology
• Forestry
• Biodiversity Studies

Background:

• Clear-cutting of powerline corridors (PLCs) fragments forests, impacting ecosystem function.
• PLCs can support biodiversity through diverse vegetation development.
• Understanding vegetation dynamics in PLCs is crucial for forest management.

Purpose of the Study:

• To determine the diversity and species composition changes caused by clear-cutting in PLCs.
• To monitor temporal changes in species composition within PLCs and adjacent forest areas.
• To compare diversity, invasive plant cover, and life form traits across different PLC zones.

Main Methods:

• Monitoring species composition in 10 permanent plots across clear-cut, forest edge, and forest interior zones.
• Comparative analysis of diversity, invasive plant cover, and life form traits.
• Redundancy analysis (RDA) for repeated measures using CANOCO 5 to assess temporal species composition changes.

Main Results:

• Clear-cutting promoted hemicryptophyte and therophyte life forms, leading to higher species richness (167 species) in PLCs compared to forest edges (117) and interiors (60).
• Species richness peaked in the second year and declined by the third year post-clear-cutting.
• Invasive plant cover was significantly higher in PLCs (23%) than in forest areas (3.78%), with limited impact on forest interior species in narrow corridors.
• Clear-cutting with slash piling encouraged undesirable tree growth (e.g., Robinia pseudoacacia), while shrub-dominated sites suppressed it.

Conclusions:

• Open-site conditions in PLCs initially boost species richness but also facilitate invasive species.
• Shrub dominance (e.g., Cistus species) can be an effective strategy for managing undesirable tree regeneration in PLCs.
• Management strategies should consider the temporal dynamics of species richness and invasive plant spread in PLCs.