This study is summarised as evidence for the following.

Action Category

Adopt certification

Action Link
Forest Conservation
  1. Adopt certification

    A controlled, before-and-after study in 2010–2011 in two mixed lowland tropical forests in Ogooué-Ivindo, Gabon (Medjibe, Putz & Romero 2013) found that once logging intensity was taken into account a certified logged forest had similar tree damage but a smaller change in above-ground biomass than a more intensively logged uncertified forest. The amount of tree biomass damaged was lower in the certified forest than in the uncertified forest (certified: 18.7; uncertified: 33.7 Mg/ha). However, there was no difference in damage between the two forests when the higher logging intensity in the conventional forest was taken into account (certified: 3.3; uncertified: 2.9 Mg/m3). The change in above-ground biomass was smaller in the certified forest (certified: 7%; uncertified: 13%), even when corrected for logging intensity. The tree species composition after logging did not change in either forest (difference in Simpson’s Index before and after harvest: certified 0.96; uncertified 0.41). The logging intensity in the certified forest was 5.7 m3/ha and 11.4 m3/ha in the uncertified forest. Twenty plots in the certified forest and 12 in the uncertified forest were established (each 200 × 50 m). Measurements were taken within each plot 2-6 months before and 2-3 months after logging for all trees with a diameter breast height > 10 cm.

Output references
What Works in Conservation

What Works in Conservation

What Works in Conservation assesses the research looking at whether interventions are beneficial or not. It is based on summarised evidence in synopses, on topics such as amphibians, bats, biodiversity in European farmland, and control of freshwater invasive species. More are available and in progress.

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