A meta-analysis of bird and mammal response to short-rotation woody crops

Abstract

Short-rotation woody cropping (SRWC) refers to silvicultural systems designed to produce woody biomass using short harvest cycles (1-15 years), intensive silvicultural techniques, high-yielding varieties, and often coppice regeneration. Recent emphasis on alternatives to fossil fuels has spurred interest in producing SRWC on privately owned and intensively managed forests of North America. We examined potential bird and small mammal response at the stand level to conversion of existing, intensively managed forests to SRWCs using meta-analysis of existing studies. We found 257 effect sizes for birds (243 effect sizes) and mammals (14 effect sizes) from 8 studies involving Populus spp. plantations. Diversity and abundance of bird guilds were lower on short-rotation plantations compared with reference woodlands, while abundance of individual bird species was more variable and not consistently higher or lower on SRWC plantations. Shrub-associated birds were more abundant on SRWC plantations, but forest-associated and cavity-nesting birds were less abundant. Effects on birds appeared to decrease with age of the SRWC plantation, but plantation age was also confounded with variation in the type of reference forest used for comparison. Both guilds and species of mammals were less abundant on SRWC plantations. These conclusions are tentative because none of these studies directly compared SRWC plantations to intensively managed forests. Plantations of SRWCs could contribute to overall landscape diversity in forest-dominated landscapes by providing shrubby habitat structure for nonforest species. However, extensive conversion of mature or intensively managed forests to SRWC would likely decrease overall diversity, especially if they replace habitat types of high conservation value.

Scientific Basis for Sustainable Management of Eucalyptus and Populus as Short-Rotation Woody Crops in the U.S.

“…Riffell et al [61] recently reviewed literature related to biodiversity and SRWCs in the U.S. and conducted a meta-analysis of bird and small mammal responses where sufficient data permitted. They characterized their findings as -tentative‖ due to the small number of studies; seven studies had data sufficient to allow meta-analysis of bird responses and only two studies provided enough information to allow meta-analysis of small mammal responses.…”

Short-rotation bioenergy stands as an alternative to spruce plantations: implications for bird biodiversity

“…A meta-analysis recently conducted in the United States found that Populus based short rotation forestry stands generally harbored lower levels of avian diversity than reference woodlands, but none of the studies directly compared short rotations stands with forest plantations (Riffell et al 2011). Likewise, comparisons of the biodiversity in short rotation production forests with broadleaves and more conventional conifer dominated production forests are largely lacking in Northern Europe.…”

Effect of Removal of Woody Biomass after Clearcutting and Intercropping Switchgrass (Panicum virgatum) with Loblolly Pine (Pinus taeda) on Rodent Diversity and Populations

“…or eucalyptus (Eucalyptus spp.) [6,7]. However, more recent efforts also have examined whether perennial grasses such as switchgrass (Panicum virgatum), a species native to eastern North America, could be intercropped between rows of crop trees in pine (Pinus spp.)…”