Influence of broadleaf trees on soil chemical properties: A retrospective study in the sub-boreal spruce zone, british columbia, canada

A retrospective study examined the influence of broadleaf trees, principall y paper birch (Betula papyrifera Marsh.), on soil properties under mixedwoo ds with lodgepole pine (Pinus contorta var. latifolia Dougl. ex Loud.) in t he Sub-Boreal Spruce zone of central British Columbia, Canada. After 23 yea rs, approximately 50% of the forest floor mass typical of mature forests in this zone had already accumulated on an initially denuded surface, but thi s new forest floor was poor in woody components. Correlation analysis found no relationship between the degree of broadleaf occupancy and total forest floor accumulation, but a significant qualitative influence on chemical pr operties of the non-woody forest floor components: higher pH, total N, avai lable P, extractable Ca, Mg, and K, and lower C:N ratios. No such relations hips existed for the surface (0-20 cm depth) mineral soils.