Plantation clear-fell patches benefit heathland arthropods

1. Plantation forests constitute a significant amount of the wooded area in many parts of the globe. However, the extent of biological provision conferred by plantation forest depends on regional conservation priorities and biogeographical context.
2. Here we evaluate the arthropod biodiversity in a chronosequence of pine planationplantation (clear-felled, 1, 3, 5, 7, 9, 13, 21-years) in the largest lowland conifer forest in the UK. We compare the assemblage within 37 plantation stands and eight important open habitat remnants in a formerly heathland dominated region. We also assess the configuration and potential isolation of ephemeral open early growth stage habitat across a 60-year plantation rotation.
3. Carabid and spider assemblages changed throughout the sampled chronosequence. In the early growth stages (1-7 years) before canopy closure, arthropod assemblages contained many individuals and species associated with dry-open habitats, greater numbers of rare species than closed canopy plantation, and had similar composition (NMDS) to heathland samples. Early growth stages and heathlands primarily differed in the additional presence of generalist species in the plantation. Species associated with woodland increased in abundance as the plantation aged, but remained far less numerous than dry-open or generalist species. The spatial distribution of young growth stages across the rotation cycle was significantly clustered in the early and late rotation phases.
4. Plantation landscapes often support high species richness but we highlight their value for vulnerable heathland biodiversity early in the rotation cycle. To increase plantation value regional conservation priorities should be supported with appropriate consideration of growth stage configuration across the full rotation.