The concept of transient assemblage dynamics (TAD) is introduced relating to the fine-scale temporal and spatial variability in substrate locations that result in greater unpredictability in bryophyte-microhabitat relationships within certain sites. An analytical test for the occurrence of TAD in a subalpine forest floor bryophyte community is outlined based on a multivariate comparison of within-plot (400m²) heterogeneity in bryophyte species assemblages and concomitant habitat conditions in sites of differing ground level stability. Plots with a higher potential for ground level turbulence showed a weaker relationship between bryophyte and habitat heterogeneity (i.e., greater degree of TAD), whereas this relationship was stronger in plots with greater ground level stability. We conclude that TAD may result in a substantial decoupling of fine-scale species-habitat linkages and recommend use of a multi-scale sampling and analytical approach for ecological studies of bryophyte communities where explanatory relationships may change at different scales.