Structural heterogeneity and old-growthness: A first regional-scale assessment of Sardinian forests


  • Sergio Fantini 1 University of Cagliari 2 Agenzia Forestas
  • Mauro Fois University of Cagliari
  • Paolo Casula Agenzia Forestas
  • Giuseppe Fenu University of Cagliari
  • Giacomo Calvia University of Cagliari
  • Gianluigi Bacchetta University of Cagliari



old-growth forests, forest ecosystems conservation, Mediterranean Basin, Structural Heterogeneity Index


Mediterranean forests have been altered by several human activities. Consequently, relatively intact forests that have been unmodified by humans for a relatively long time (i.e., old-growth forests) are often reduced to isolated and fragmented stands. However, despite their high conservation value, little is known about their features and even presence several Mediterranean areas. First steps of their investigation are based on the identification of old-growth features such as amount of large‐size and old trees, tree species composition, canopy heterogeneity, occurrence and amount of deadwood. The Structural Heterogeneity Index (SHI) is commonly used to summarise features of old-growthness in one single value. Here, the SHI was derived for 68 plots included in 45 forest stands within the 4,297 km2 of territory that is covered by forests in Sardinia. SHI values were affected by variables that are likely to be related to forest age and structural complexity, such as presence of cerambycids, canopy cover, forest layers, location and three old-growthness classes. Results confirm a high structural variability among forests with old-growth features, determined by the presence, or lack, of given living and deadwood features. Our findings identified, for the first time, most of the forest stands that need special protection in Sardinia for the presence of old-growth features. In this sense, the SHI was confirmed useful for improving their management and conservation, although more specific and deeper studies are necessary for better understanding their species composition and dynamics.

Author Biographies

Sergio Fantini, 1 University of Cagliari 2 Agenzia Forestas

Department of Life and Environmental Science, PhD student Agenzia Forestas, Technician  

Mauro Fois, University of Cagliari

Department of Life and Environmental Science, researcher

Paolo Casula, Agenzia Forestas

Agenzia Forestas, Technician

Giuseppe Fenu, University of Cagliari

Department of Life and Environmental Science, Associate Professor

Giacomo Calvia, University of Cagliari

Department of Life and Environmental Science, PhD student

Gianluigi Bacchetta, University of Cagliari

Department of Life and Environmental Science, Full Professor


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