Socio-ecological implications of modifying rotation lengths in forestry

Abstract

The rotation length is a key component of even-aged forest management systems. Using Fennoscandian forestry as a case, we review the socio-ecological implications of modifying rotation lengths relative to current practice by evaluating effects on a range of ecosystem services and on biodiversity conservation. The effects of shortening rotations on provisioning services are expected to be mostly negative to neutral (e.g. production of wood, bilberries, reindeer forage), while those of extending rotations would be more varied. Shortening rotations may help limit damage by some of today’s major damaging agents (e.g. root rot, cambium-feeding insects), but may also increase other damage types (e.g. regeneration pests) and impede climate mitigation. Supporting (water, soil nutrients) and cultural (aesthetics, cultural heritage) ecosystem services would generally be affected negatively by shortened rotations and positively by extended rotations, as would most biodiversity indicators. Several effect modifiers, such as changes to thinning regimes, could alter these patterns.

The effect of forest owner decision-making, climatic change and societal demands on land-use change and ecosystem service provision in Sweden

“…The lower mean national forest age reached under SSP-RCP scenarios also entailed smaller annual timber harvests nationally as younger forests were being felled, and this keeps carbon sequestration, biodiversity and recreation at lower levels. These findings confirm qualitative results from Roberge et al (2016), who suggest that the provision of supporting and cultural ES, and economic outputs from timber would be negatively impacted by shorter rotations in Fennoscandian forests. This phenomenon is explained by changes in demand levels and climate change, which together prompt forest managers to adapt their management activities more frequently and dramatically than they would otherwise do (with the size of this effect depending on the balance between the costs of early felling, timber prices and potential profits from alternative management strategies).This effect is consistent with the ongoing consideration of management alternatives (e.g.…”

Forest management and carbon sequestration in the Mediterranean region: A review

“…Extending the rotation period has been identified as a suitable management approach with regard to carbon storage both for tree biomass and soil carbon (Liski et al, 2001;Bravo et al, 2008a;Sohngen & Brown, 2008;Roberge et al, 2016). Optimal rotations have traditionally been defined by economic objectives, subject to temporal burdens, neglecting the potential that mature stands still possess in terms of tree growth.…”

Adaptation to Climate Change in Swedish Forestry

“…Supporting (water, soil nutrients) and cultural (aesthetics, cultural heritage) ecosystem services would generally be affected negatively by shortened rotations and positively by extended rotations, as would most biodiversity indicators. [48] Interestingly, shortening rotations comes in conflict with the climate mitigation strategy of extending rotations, which has been proposed as a tool to increase carbon stocks in forest [49]). Research thus only to some extent supports the Commission proposal that rotation length be decreased.…”