Harvesting intensity affects forest structure and composition in an upland Amazonian forest

  • Published source details Parrotta J.A., Francis J.K. & Knowles O.H. (2002) Harvesting intensity affects forest structure and composition in an upland Amazonian forest. Forest Ecology and Management, 169, 243-255.


This study is summarised as evidence for the following.

Action Category

Use clearcutting to increase understory diversity

Action Link
Forest Conservation
  1. Use clearcutting to increase understory diversity

    A replicated, randomized, controlled study in 1985-1997 in tropical forest in Pará State, Brazil (Parrotta, Francis & Knowles 2004) found that clearcuttng decreased species richness, density and size of trees, but not species richness, density and size of vines, herbaceous species and grasses. Species richness of trees (>15 cm diameter at breast height) was higher in uncut (20/plot) and low intensity cuts (20) than in clearcut and moderate intensity cuts plots (clearcutting: 7/plot; moderate-intensity: 12). Numbers of trees/ha was lower in moderate intensity cut plots (164) than in the other treatments (uncut: 323; low intensity: 339; clearcut: 296). Trees basal area (m2/ha) was higher in low (16) and moderate intensity cuts (17) than in clearcuts (9) and highest in uncut plots (uncut: 25). Density of vines (uncut: 17,468; low intensity: 8,758; moderate intensity: 11,174; clearcuts: 9,268), herbaceous species (uncut: 1,210; low intensity: 1,131; moderate intensity: 1,401; clearcuts: 1,417) and grasses (uncut: 334; low intensity: 223; moderate intensity: 270; clearcuts: 6,362), and species richness/plot of vines (uncut: 13; low intensity: 13; moderate intensity: 12; clearcuts: 12), herbaceous species (uncut: 3; low intensity: 2; moderate intensity 2; clearcuts: 3) and grasses (<1 in all treatments) were similar between treatments.  Data were collected in 1996-1997 in four treatments (20 × 70 m2): uncut, low intensity cuts (trees ≥45 cm diameter at breast height removed), moderate intensity cuts (trees ≤20 and ≥60 cm removed), and clearcutting, replicated randomly in four blocks in 1985.


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