Individual tree crown (ITC) techniques
- Individual tree crown (ITC) delineation: Identification, and regrouping in high spatial resolution (30-100 cm/pixel) aerial and satellite multispectral images
- Individual tree crown delineation: A valley-following approach
- Individual tree crown multispectral classification in high spatial resolution images
- Supervised classification of automatically delineated tree crowns at different spatial resolutions
- Regrouping tree crowns into forest stands (or environmental strata) and obtaining detailed information about their content
Regrouping tree crowns into forest stands (or environmental strata) and obtaining detailed information about their content
(a)
(b)
Fig. a - Pseudo-colour infrared rendition of a sub-area of a Casi image (60 cm/pixel) of the Nahmint Lake species trial area in the central forest of Vancouver Island, British Columbia, Canada. The delineated areas (in white) correspond to stands judged relatively uniform by a forester. The training and testing areas used for the classification were delineated where species are known to be homogeneous. Their respective species and colours are: Douglas-fir (Pseudotsuga menziesii) in red, grand fir (Abies grandis) in green, amabilis fir (Abies amabilis) in blue, westerm redcedar (Thuja plicata) in orange, and western hemlock (Tsuga heterophylla) in yellow.
Fig. b - The individual tree crown (ITC) classification of Figure (a) and its computer generated forest stand outlines using the same colour scheme as Figure (a).
Tranfer of detailled forest information to a geographic information system (GIS)
The ITC approach provides detailled information about forest stand content by attaching new stand attributes that summarize the individual tree crown information. For each stand, ITCPCD produces and populates fields summarizing its area (by pixels and by hectares) the number of ITCs, the crown closure and the stem density of the stand. For each species (SP01, SP02, ...), its presence is summarized in terms of the number of ITCs (ITCsnn), its percentage of the total ITCs in the stand (PERnn), its percentage of crown closure (CCnn), its stem density (SDnn) and its average crown diameter (DIAnn).
If a digital canopy height model is available, average tree height information is also reported for the stand and for each species. All this information is easily transfered to geographic information systems.
|
Area (p) |
Area (ha) |
ITCs | Closure | Density | SP01 | ITCs01 | PER01 | CC01 | SD01 | DIA01 | SP02 | ITCs02 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 344478 | 8.61 | 2329 | 59.2 | 270 | 49 | 1193 | 51.2 | 62.5 | 138 | 5.8 | 50 | ... |
| 394856 | 9.87 | 2858 | 57.3 | 289 | 50 | 1024 | 35.8 | 29 | 103 | 4.5 | 47 | ... |
| 291189 | 7.28 | 1562 | 48.4 | 214 | 50 | 376 | 24.1 | 18.4 | 51 | 4.7 | 47 | ... |
| 114189 | 2.85 | 797 | 56.4 | 279 | 50 | 478 | 60 | 54.9 | 167 | 4.9 | 49 | ... |
| 751854 | 18.8 | 5330 | 56.5 | 283 | 49 | 1241 | 23.3 | 24.7 | 66 | 5.2 | 50 | ... |
| 963858 | 24.1 | 6416 | 52 | 266 | 46 | 2087 | 32.5 | 38.3 | 86 | 5.4 | 49 | ... |
| 226425 | 5.66 | 1456 | 60.1 | 257 | 49 | 603 | 41.4 | 45.5 | 106 | 5.7 | 50 | ... |
| 290765 | 7.27 | 2060 | 56.2 | 283 | 49 | 605 | 29.4 | 29.8 | 83 | 5.1 | 50 | ... |
| 321607 | 8.04 | 2392 | 56.8 | 297 | 49 | 766 | 32 | 29.6 | 95 | 4.7 | 46 | ... |
| 155049 | 3.88 | 1116 | 56.6 | 287 | 49 | 511 | 45.8 | 43.7 | 131 | 4.9 | 46 | ... |
| 249622 | 6.24 | 1743 | 58.2 | 279 | 50 | 628 | 36 | 30.1 | 100 | 4.7 | 49 | ... |
| 648686 | 16.22 | 4386 | 58 | 270 | 50 | 2218 | 50.6 | 53.2 | 136 | 5.4 | 51 | ... |
Typical fields added by ITCPCD as forest stand attributes.
Project status
- On-going