A pressing question in forest management is the adequacy of reserves and off-reserve management in maintaining forest-dependent biota in production forest landscapes. Through Regional Forest Agreements, the Comprehensive, Adequate and Representative (CAR) reserve system, coupled with complimentary off-reserve management, has been adopted as the primary mechanism for adequately protecting biodiversity in Australia’s forests. The CAR reserve system is particularly important for mature forest, since this is the development stage that is usually most depleted in production forests managed on rotations of less than 100 years. Tasmania has a high level of reservation by world standards. However, the reserves, both formal and informal, are not distributed uniformly through the landscape. In production forest landscapes, at the Forest Block scale ( the scale at which much management planning is conducted), their density is highly variable. The adequacy of this arrangement in protecting species dependent on mature forest has recently been challenged in Tasmania (Brown versus Forestry Tasmania). The legal debate highlighted the scientific uncertainty surrounding this issue.
Forestry Tasmania has established the Southern Forests Experimental Forest Landscape (SFEFL), anchored to the Warra Long Term Ecological Research (LTER) site and extending eastwards to the Huon estuary, to undertake studies to address such landscape-level questions. Supporting the SFEFL is a detailed knowledge-base of the local biodiversity developed through studies carried out in the Warra LTER site and its environs. This knowledge-base will facilitate the selection of appropriate focal taxa to measure biodiversity responses to forest management. The SFEFL provides a gradient in land-use intensity (from pristine wilderness to long-rotation forestry to extensive native forest silviculture to intensive native forest silviculture to plantations to agriculture) within a relatively uniform biophysical environment. An extensive network of CAR reserves within the SFEFL provides an opportunity to measure the biological responses of selected taxa along that gradient of land-use intensity and to test the extent to which those responses are influenced by proximity to, and concentration of, mature forest in the surrounding landscape.
The proposed study will use a replicated pair-plot design along a gradient of land-use intensity to compare biological responses in harvested areas with the nearest area of mature forest. The aim is to determine: (a) if viable mature forest habitat is maintained in CAR reserves as land-use intensity increases, and (b) the effect of proximity to mature forest in influencing recolonisation of mature forest biota in harvested areas and whether that effect is maintained as land-use intensity increases. A supplementary aim is to test a metric (mature forest proximity) that has been proposed as a tool to measure the levels of mature forest in the production landscape and hence to identify areas where there may be a deficiency in the amount of mature forest.
Follow these links to view information on subsidiary projects: a comparison of CWD volumes between mature and regenerated eucalypt forest; the response of saproxylic beetles to landscape context; the comparison of sampling techniques for saproxylic beetles; the response of birds to landscape context; and the response of vascular plants and forest structure to landscape context.
