Jay Wosaree, Alberta Innovates — Technology Futures
February 2012
Ecological > Best Practices
Executive Summary
This study examined three pervasive issues that impacted native ecosystems.
o Numerous land use practices including oil and gas activities have led to the modification of native grasslands both the within the Northern Fescue Region and the Foothills Fescue Region. Is it possible to eradicate non-native species from well leases and pipelines that were previously seeded to non-native forages, and what is the potential for invasive non-native species to convert rough fescue grasslands to non‐native communities and can they be restored?
o Can specific salt and hydrocarbon tolerant plant species be used to remediate areas affected by pipeline breaks or produced salt water and hydrocarbon spills?
o A critical part to reclamation is to have appropriate plant materials. Does industry have access to native species? What species are needed and how are they efficiently brought into commercial production?
Non-native invasive species such as Bromus inermis (Smooth brome grass), Agropyron pectiniforme (Crested wheatgrass), Phleum pratense (Timothy), Cirsium arvense (Canada thistle can be eradicated from disturbed sites that were previously seeded to non-native forages. Properly timed and applied herbicide applications followed by mowing and followed by seeding with appropriate native species may provide an effective solution in restoring these grasslands. Once seeded to native species, the successional pathways and the influence of non-native species on the area remains uncertain due to other anthropogenic activities on the landscapes.
At the Rumsey Parkland sites, a number of native grasses and forbs are now growing on the sites, however percent cover provided by Festuca halli represents a small percentage.
At the Longview sites, fewer establishments has occurred. Climate and soils play a major role in reclamation success. A dry spell after seeding followed by periods of high precipitation and a rich organic soil proved more favourable to the non-native species. Nutrient and soil microbes were abundant within the soil. Can foothill grasslands be restored? The sites were re-seeded in fall of 2011 and we anticipate establishment in the coming season.
In native species propagation research; we had good establishment of many species such as Elymus innovatus (hairy wild rye), Oryzopsis asperifolia (White grained mountain rice grass), Astragalus canadensis (Canada milk vetch), Stipa richardsonii (Richardson’s needle grass), Deschampsia caespitosa 3 (tufted hair grass), Bouteloua gracilis (blue grama), Danthonia intermedia (timber oat grass), Festuca campestris (foothills rough fescue), Festuca hallii (plains rough fescue) and Festuca saximontana (Rocky Mountain fescue) – Parkland ecotype.
Others such as Helictotrichon hookeri (Hooker’s oat grass), Puccinellia nuttalliana (Nuttall’s alkali grass), Hesperostipa comata (needle and thread grass), Lathyrus venosus (pea vine),and Vicia americana (American vetch) proved to be more difficult either due to poor germination or to insects and wildlife issues in the field.
Shrubby and forb species differed considerably in their ability to germinate, while some species proved easy to grow. Vibernum opulus (low bush cranberry), Arctostaphylos uva-ursi (bearberry) and Shepherdia canadensis (buffalo berry) are thriving after transplanting within a grassy field at Vegreville. The inclusion of forbs and shrubby species into reclamation practices help to improve the structural layers within the site and can accelerate recovery of the site to its former biological processes and intrinsic value.
Results collected from sites affected by salt spill or pipeline break showed that beneficial microorganisms do occur naturally in contaminated soils. The use of specific salt and hydrocarbon tolerant plant species showed tolerance to F2, F3 and F4 hydrocarbons. Organic amendments such as manure followed by aeration of the site seem to benefit plant growth at the Husky Energy Sites. Forage growth is improving on the sites. At the Zapata site, no amendments were used, and plants are making slow ingress towards the most severely affected areas of the site. This may have potential for deviating from the old practice of land farming. The recovery process is slow and can be expected to take more than 10 years.
In conclusion, these sites need to be monitored to ensure they settle into the desired trajectories, along with management practices (selective application of herbicide, mowing, grazing), otherwise the whole effort will result in an ecosystem very different from the one intended.
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