COS 209-5 - Are restored seismic lines heading in the right direction? Comparing taxonomic, phylogenetic and functional plant diversity in boreal peatlands

Background/Question/Methods

Land-use changes, including anthropogenic disturbances, are major threats to global biodiversity, with impacts on ecosystem function and post-disturbance recovery. Human activities from petroleum development in boreal Alberta, Canada, have resulted in highly fragmented landscapes, in part due to seismic exploration lines that remove surface vegetation and microtopography. Although forest cover on seismic lines in some uplands appear to recover over time, peatlands do not seem to recover and impacts on wildlife and carbon dynamics remain even decades after seismic line construction. Recent restoration efforts apply silviculture techniques to recreate microtopography and promote tree seedling growth. Whether these restoration treatments are successful in recovering plant diversity in boreal peatlands remains a critical knowledge gap. We compared taxonomic, phylogenetic, and functional diversity of the ground layer plant community in treed bogs and fens across treated and untreated seismic lines, and reference sites. We measured relative abundance and evolutionary relationships among species and obtained functional trait data for plant height (H), leaf dry matter content (LDMC), and foliar nitrogen (N) and phosphorus (P) contents.

Results/Conclusions

Treated lines differed from untreated lines and reference sites, with shifts towards higher community-weighted H, LDMC, N and P. In bogs, treated lines were more diverse, driven by horsetails, forbs, and graminoids with larger leaf N and P content. In fens, taxonomic and phylogenetic diversity of treated lines differed from reference sites, while functional diversity was similar to reference conditions. Results reveal that bog and fen communities respond differently to seismic line disturbance and restoration, which needs to be considered during management and restoration planning. Changes in plant diversity have implications for ecosystem recovery and functions, especially carbon and nutrient cycling. Although these changes may be temporary as communities continue to undergo succession, long-term monitoring is needed to assess the eventual success of silviculture techniques on boreal peatland recovery.