Creating Microsites And Seedbeds For Improved Emergence And Establishment For Reclamation In Prairie And Parkland Ecoregions of Alberta, Canada

ANAYANSI COHEN-FERNÁNDEZ; FEDERICO MOLLARD; ZHICHAO JIAO; M. ANNE NAETH

Potsdam

Encuentro; 2nd HAI Science Forum; 2012

Helmholtz-Alberta Initiative

After disturbance, sites to be reclaimed commonly present unfavourable conditions for establishment of a target plant community. Sub and supra optimal temperatures of denuded soil and limited soil water and nutrient availability hinder germination, emergence and seedling survival. Increased germination may be achieved through creation of favourable microsites and seeding a diversity of species; microenvironment spatial variability can increase vegetation density and richness. Our research aims to understand the effect of fine scale environmental heterogeneity of constructed microsites on germination, emergence and plant establishment of native plant communities with different soils and disturbances (old land fill, old agricultural field, well pad). The experimental design is completely randomized. Three micro topographic treatments consisting of mounds, depressions and flat land are being assessed in combination with five microsite modifiers and an unmodified control. The modifiers are erosion control blankets, straw, fresh grass or hay, manure and hydrogel. Treatments were applied to 2 x 2 m plots and replicated five times. Plots were broadcast seeded in June 2012 with native grasses and forbs (Agropyron trachycaulum, Bromus ciliatus, Stipa comata, Bouteloua gracilis, Koeleria macratha, Linum lewisii, Geum triflorum, Astragalus canadensis). Soil water content, temperature and electrical conductivity are being monitored with 5TE sensors (Decagon) installed in selected plots. The light environment is being characterized with a light meter (Licor). Vegetation is being monitored every two weeks from July to August 2012 and less frequently in subsequent years. Preliminary results from the first monitoring in July suggest depressions microsites favour early emergence and establishment of seeded species and blanket, hay or grass and hydrogel are most favourable amendments. Treatments affected seeded species differently. Mounds created a clear gradient of temperature with south aspects highest and north aspects lowest. Hay or grass lowered the range of temperature change in the soil. Blanket, hay and straw treatments reduced light irradiance.