Mammals showed no changes in richness, abundance and composition.
We describe changes in richness, diversity, and species composition of fungal communities of trembling aspen logs and snags caused by these silvicultural practices.
By looking at changes in richness over time, we found that fragmentation affected the dynamics of species richness, as opposed to static values of species richness.
Many studies use annual monitoring to quantify changes in richness or abundance of communities, yet few studies explicitly test for progressive changes in community similarity.
Collectively, these changes in richness and abundance did not produce significant trends in successive similarity (year-to-year changes) for any guild except Neotropical migrants, indicating that successive similarity was constant over time (Table 1; Figure 2e,f).
Unexpectedly, decreases in progressive similarity resulted from small changes in richness (<1 species per route for the 22-year study period) and modest losses in abundance (−28.7 −10.2 individuals per route) that varied by migratory habit and nest location.
So as not to average out changes in richness across several years, we only calculated this metric when the surveys of a given plot were separated by one year.
However, successive similarity may offer a false sense of security regarding the status of communities when relatively small changes in richness or abundance values accumulate over time, resulting in substantial long-term changes in communities when compared to historic baseline conditions that successive similarity cannot detect.
We found evidence of significant but subtle changes in richness over the 22-year study period for Neotropical migrants (annual trend of −0.036×22 years = −0.79 species per route), permanent residents (+0.84 species), and cavity nesters (+0.37 species) (Table 1; Figure 2a,b).
This allows the assessment of the changes in richness of the bacterial populations.
