Natural Recovery of Rough Fescue (Festuca hallii (Vasey) Piper) Grassland after Disturbance by Pipeline Construction in Central Alberta, Canada

摘要

Many attempts to restore grasslands after pipeline construction, including soil manipulation such as topsoil stripping and replacement, and revegetation methods such as seeding native species or non-native cover species, have been unsuccessful. Recent pipeline techniques have used minimum disturbance and revegetation via natural recovery. The goal of this research was to evaluate natural recovery in rough fescue (Festuca hallii (Vasey) Piper) grassland in central Alberta, Canada. Plant species cover was evaluated, comparing pipeline right-of-way disturbances to undisturbed controls. Pipeline construction methods were assessed to determine which would be most successful in returning native grassland species. Pipelines with the most intense disturbances were dominated by wheatgrasses, with abundant bare ground and sparse moss and lichen cover; whereas those with the least intense disturbances had cover similar to native grassland. Results confirmed the importance of minimum disturbance in grasslands. Retaining grassland sod through plow-in pipeline construction and keeping disturbance as narrow as possible is critical to successful recovery. Rough fescue appears to recover better with plow-in pipeline construction than with seeding, most likely from intact sod. Therefore, narrow trenching with plow-in techniques is recommended for grasslands.