title: Using fragmentation to assess degradation of forest edges in Democratic Republic of Congo.
abstract: BACKGROUND
  Recent studies have shown that fragmentation is an increasing threat to global forests, which has major impacts on biodiversity and the important ecosystem services provided by forested landscapes. Several tools have been developed to evaluate global patterns of fragmentation, which have potential applications for REDD+. We study how canopy height and above ground biomass (AGB) change across several categories of forest edges determined by fragmentation analysis. We use Democratic Republic of Congo (DRC) as an example.
  
  
  RESULTS
  An analysis of variance of different edge widths and airborne estimated canopy height found that canopy heights were significantly different in forest edges at a distance of 100 m from the nonforest edge. Biomass was significantly different between fragmentation classes at an edge distance of 300 m. Core forest types were found to have significantly higher canopy height and greater AGB than forest edges and patches, where height and biomass decrease significantly as the level of fragmentation increases. A change analysis shows that deforestation and degradation are increasing over time and biomass loss associated with degradation account for at least one quarter of total loss. We estimate that about 80 % of primary forests are intact, which decreases 3.5 % over the 15 year study period, as primary forest is either deforested or transitioned to forest edge. While the carbon loss per hectare is lower than that of deforestation, degradation potentially affects up to three times more area than deforestation alone.
  
  
  CONCLUSIONS
  When defining forest degradation by decreased biomass without any loss in forest area, assessing transitions of core forest to edges over time can contribute an important element to REDD+MRV systems. The estimation of changes between different forest fragmentation types and their associated biomass loss can provide an estimate of degradation carbon emission factors. Forest degradation and emissions due to fragmentation are often underestimated and should comprise an essential component of MRV systems.
authors.affiliation: World Wide Fund for Nature Germany, Reinhardtstr 18, 10117 Berlin, Germany.
authors.forename: Aurélie C
authors.initials: AC
authors.lastname: Shapiro
authors.affiliation: World Wildlife Fund-US Forest and Climate Program, 1250 24th st. NW, Washington, DC 20037 USA.
authors.forename: Naikoa
authors.initials: N
authors.lastname: Aguilar-Amuchastegui
authors.affiliation: Geography Department, Humboldt Universität zu Berlin, Unter Den Linden 6, 10099 Berlin, Germany ; Integrative Research Institute On Transformations of Human-Environment Systems (IRI THESys), Humboldt Universität zu Berlin, Unter Den Linden 6, 10099 Berlin, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Hostert
authors.affiliation: Landscape Ecology and Plant Production Systems Unit, Université Libre de Bruxelles, CP264-2, B-1050 Brussels, Belgium ; BIOSE Department, Gembloux Agro-Bio Tech, Université de Liège, B-5030 Gembloux, Belgium.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Bastin
keywords: Biomass; Conservation; Emissions; Forest degradation; Fragmentation; REDD