Effects of upland clearcutting and riparian partial harvesting on leaf pack breakdown and aquatic invertebrates in boreal forest streams

Abstract

1. Leaf litter breakdown and associated invertebrates were compared among three logged and three reference stream reaches 2-3 years before and 3-4 years after logging to assess the environmental impacts of partial-harvest logging as a novel riparian management strategy for boreal forest streams. 2. Partial-harvest logging at three sites resulted in 10, 21 and 28% average basal area removal from riparian buffers adjacent to upland clear-cut areas. 3. Leaf litter breakdown rates were not significantly different between reference and logged sites after logging, but litter breakdown was significantly different from year to year at all sites. 4. Significant post-logging differences in aquatic invertebrate communities were detected at only one of the three logged sites. These differences were largely the result of increases in some leaf-shredding stoneflies and a detritivorous mayfly and a decrease in a chironomid group 2-4 years after logging. This site where significant change was detected had the lowest intensity of riparian logging (average 10% removal) but the highest proportion of the catchment area that was clear cut (85%). 5.The post-logging differences in invertebrate communities at this site were more related to catchment-wide influences (e.g. weather patterns, water yield, possibly upland clearcutting) than to reach-level disturbances from riparian logging. 6.The study indicates that partial-harvest logging in riparian buffers at up to 50% removal should pose little risk of harm to leaf litter breakdown processes or aquatic invertebrate communities beyond any impacts that might arise from upland logging disturbance or catchment-wide influences. However, the results should be viewed in the context of the natural disturbance (summer drought conditions) through the post-logging assessment period of this study. Post-logging summer drought conditions may have masked or confounded logging impacts on streams.

Relations of interannual differences in stream litter breakdown with discharge: bioassessment implications

“…For example, the range of temporal CV of k c (~26–54%) and k f (~37–46%) in three forested reference streams in WR during 2002–2007 (Kreutzweiser et al. ) was comparable to that of the present study sites within the same region (i.e., ~10–50%; Table ). Temporal CV of k c in Satellite Branch, Coweeta Hydrologic Laboratory, USA, was 27% for rhododendron, Rhododendron maximum L. (6 yr; 1985–1990), and 28% for red maple, Acer rubrum L. (7 yr; 1985–1990, 1992; Webster et al.…”

“…This is because (1) shredder communities are known to vary markedly with hydrologic variability (Kreutzweiser et al. , Imberger et al. ); (2) shredders tend to exert much greater control on breakdown than microbes (Hieber and Gessner , Kreutzweiser et al.…”

“…); (2) shredders tend to exert much greater control on breakdown than microbes (Hieber and Gessner , Kreutzweiser et al. , Kominoski et al. , Lecerf ); and (3) the contribution of microbial decomposition to breakdown was shown to vary little with current velocity (Ferreira et al.…”

Linking stream ecosystem integrity to catchment and reach conditions in an intensively managed forest landscape

“…, Mckie and Malmqvist , Kreutzweiser et al. , Yeung et al. ), and, in turn, affect the delivery of aquatic ecosystem services (Balvanera et al.…”

Influence ofLonicera maackiiInvasion on Leaf Litter Decomposition and Macroinvertebrate Communities in an Urban Stream

“…Streams with riparian zones densely colonized by this invasive shrub would be expected to have a low abundance of macroinvertebrates across a range in FFGs; this trend was detectable, even in this highly disturbed, urban stream. Anthropogenic influences such as increased impervious surface, increased nutrient inputs, and decreased riparian buffer zones have significantly influenced the leaf litter decomposition and associated invertebrate communities in stream ecosystems (Gulis and Suberkropp 2003;Chadwick et al 2006;Krutzweiser et al 2010), and the introduction of invasive plant species to riparian areas could have multiple cascading effects on aquatic structure and function. Managing L. maackii invasions in urban riparian habitats could help increase macroinvertebrate abundance over time, potentially increasing not only decomposition, but also other ecosystem services such as filtration, secondary production, and nutrient recycling as well (Lecerf and Richardson 2010).…”