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THE NATIONAL FOREST INVENTORY (NFI) Data collected on the field

Data collected on the field

The following types of data are collected on the plots:
-  25 m radius: stand type, stand structure, stand composition, crown description and crown cover measurement, regeneration, topography
-  15 m radius: flora determination (species presence and cover), measurement of trees larger than 177.5 cm in circumference at 1.3 m
-  9 m radius: measurement of trees larger than 70.5 cm in circumference at 1.3 m
-  6 m radius: measurement of trees larger than 23.5 cm in circumference at 1.3 m
They are detailed below.

Identification and description data

  • Author
  • Date
  • Time of access
  • Positioning type (central knot positioned with orthophoto/landmark/GPS)
  • Land cover
  • Details on non-forested area
  • Main use
  • Wood availability
  • Other use
  • Size of the land cover unit

Stand data

  • Limits on a 25 meters radius
  • Uncountable tree population
  • Main planted species
  • Limits on a 15 meters radius
  • Vertical structure
  • Secondary planted species
  • Distance and azimuth between the center of the plot and the limits
  • Forest management indicators
  • Skidding itinerary
  • Presence of a border
  • Nature and intensity of incident
  • Exploitation slope
  • Border coverType of cut
  • Floor load capacity
  • Total land cover rate
  • Type of plantation

Tree data

  • Vegetation state
  • Tree canopy cover rate
  • Total tree height
  • Tree species
  • Nature of accident
  • Type of tree cut
  • Tree circumference at 1.30 m
  • Trunk quality
  • Branches mortality
  • Distance and azimuth between tree and central knot
  • Tree growth on n years
  • Tree origin Tree age at 1.30 m

Ecology data

  • Author
  • Distance, type and level of hydrographic unit
  • Stones size and density
  • Date
  • Slope
  • Bedrock type
  • Floristic background
  • Exposition
  • Texture of geological horizons
  • Tree cover
  • Soil background
  • Soil type
  • Herbaceous cover
  • Distance and azimuth between central knot and pit
  • Tree species
  • Bryophytes cover
  • Soil litter
  • Tree canopy cover rate
  • Topographic position
  • Humus type
  • Dead wood on the ground

Habitats data

  • Type and description of the habitat(s)

Linear tree formations data

  • Type and description of the formation(s)