Forest degradation

1
Forest degradation

• P. Van Laake, T. Groen, B. Turner,
• P. Dart and Nguyen Tan

2
(Human induced) Forest degradation

• Definition Is it
• Any reduction in biomass of forest and thus of
  the C stock, OR
• Any reduction in capacity of forest to sequester
  C in the long term?
• Not necessarily the same!
• IPCC (2004) says some 60 definitions, e.g.,
• The reduction of the capacity of a forest to
  produce goods and
• services. Capacity includes the maintenance of
  ecosystem structure
• and functions. (ITTO, 2005)
• Possible causes
• Partial harvesting (legal or illegal)
• Silvicultural thinning
• (Human induced) Fire

3
Detection of degradation

• Multi-date imagery best
• Before and after, but dont know when it will
  occur usually, so
• Frequent surveillance (e.g., annually) necessary
• Degree of degradation
• Amount of difference in spectral characteristics
• Time taken to recover to previous condition
• Ground checking needed
• Need high resolution (1ha or smaller) to detect
  partial harvesting or thinning