The effect of salinity on the emergence and seedling growth of Picea mariana, Picea glauca, and Pinus banksiana.

Mining operations in areas of the boreal forest have caused salinity issues to be a major concern for reclamation. One of the factors determining successful reclamation is the ability of species to self-propagate. The effects of salinity on the seedling emergence and early growth of three boreal forest conifers: Picea mariana, Picea glauca, and Pinus banksiana were determined. Seeds were planted in sand moistened with solutions of various concentrations of sodium chloride or sodium sulfate. Seedling emergence was monitored on a daily basis and growth parameters assessed after 6 weeks. The emergence of Pinus banksiana seedlings was least affected by salinity, and at certain concentrations, emergence even appeared to be stimulated by the presence of salt. Picea glauca was the most sensitive of the species studied. Hypertrophia was observed in all species at high concentrations of Na2SO4, and an increase in salt levels caused a corresponding reduction in seedling height and weight, root length and number of lateral roots.