Vegetation patterns and site relationships in the Saskatchewan River delta

Abstract

This 5-year study attempted to order the landscape pattern of the flood plain complex in the Saskatchewan River delta. The approach involved a stepwise progression, from traditional, subjective classification of the vegetation and mapping by air photo interpretation, to objective classification using association analysis, and final verification by stand and species ordinations through principal component analysis of bog, fen, and mixed forest types. Association analysis efficiently separated the wide vegetational variation according to discontinuities in species composition. The terminal groups of stands showed pronounced affinities for distinct positions in the landscape. The application of principal component analysis to these landscape units showed moisture regime, nutrient status, and pH to be the most significant gradients controlling distribution of species and communities. The interactions of these factors with each other, and with several physical characteristics, have been revealed.