Download (PDF 2.41 MB): https://research.fs.usda.gov/download/treesearch/30443.pdf
Abstract
Coniferous stands that regenerate following clearcutting in southeast Alaska can be characterized by the amount of soil disturbance during logging. There are indications that red alder in mixed stands mitigates some of the negative effects of clearcutting. We compared invertebrate biomass in four stands each of (1) young conifers, (2) young mixed alder and conifer, and (3) old conifers to determine if alder was beneficial to invertebrates. Collembola, then Aranac taxa were most abundant but Colcoptera had the greatest invertebrate biomass on boles of red alder, Sitka spruce, or western hemlock. Diptera taxa were the most abundant in flight traps in young mixed alder and confier stands. Psocoptera taxa were the most abundant invertebrates collected from any foliage. Some rarer invertebrate families were unique to one or another of the tree species. Crawling invertebrate species richness was greatest on red alder and in young mixed alder and conifer stands. The greatest biomass of crawling invertebrates occurred on Sitka spruce boles. Old stands had about the same invertebrate biomass as mixed alder or conifer young stands. Flying invertebrate biomass and species richness was greatest in young stands of mixed alder and conifer. Twice as many invertebrate species were found on western hemlock or Sitka spruce foliage as on red alder foliage but invertebrate species richness was greatest on red alder. Invertebrate biomass on red alder foliage was 20 to 100 times greater than on the equivalent weight of Sitka spruce or western hemlock foliage. Red alder significantly contributes invertebrate species richness and biomass to young forest stands of southeast Alaska.
Citation
Schultz, Mark E.; De Santo, Toni L. 2008. Comparison of terrestrial invertebrate biomass and richness in young mixed red alder-conifer, young conifer, and old conifer stands of southeast Alaska. Northwest Science. 80(2): 120-132
