(IX-B8, 2012 
  
  
  
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ent phenological 
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Only pixels with 
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ce species in the 
a. 
    
  
  
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B8, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
3. RESULTS 
Preliminary results show remarkable distinction between well- 
conserved and degraded monteverde forest (figure 3a). 
However, subsequent MESMA cycles were needed to separate 
very similar species, like M. faya and L. novocanariensis 
(figure 3b). 
  
Figure 3. Results obtained from MESMA. Colored 
images represent combinations of three endmembers 
corresponding to species or group of species used in the 
analysis; each color intensity correlates to the cover fraction of 
the species. a) mesmal: M. faya + L. novocanariensis (RED), 
E. arborea (GREEN) and fern-herbaceous (BLUE). b) 
mesma2: M. faya (RED), L. novocanariensis (GREEN) and 
P.radiata (BLUE). c) Shade fractions estimates, darker cells 
corresponding to lower proportion of shade. 
  
  
  
Total Sc 
Endmember distribution Q2 Q3 
area (ha) p 
; 1 t 88.9 536 | 070 | 0.86 
3 2 (Erica) 54.5 132 018 | 033 
3 (fern/herb.) 31.5 3.8 0.08 | 0.15 
« | 1 (Morella) 28.3 18.5 0.67 | 0.86 
E 2 (Laurus) 22.8 8.2 031 | 051 
s 3 (Pinus) 122 33 0.19 | 0.37 
  
  
  
  
  
  
  
  
Table 2. Overall species distribution areas obtained after 
mesmal and mesma2. The total distribution area is derived 
from the total number of cells where the species were detected, 
whereas the actual cover area takes into account the species 
cover fraction in each cell as well. Q2 and Q3 correspond to 
the 50" and 75" percentile respectively. 
  
  
  
  
Endmember Mature Degraded Pine 
forest forest plantation 
à ur qe 0.62 0.09 0.57 
: 2 (Erica) 0.23 0.01 0.11 
3 (fern/herb.) 0.09 0 0.07 
a | | (Morella) 0.12 - 0.04 0.14 
E 2 (Laurus) 0.03 0.14 0.11 
E 3 (Pinus) 0.04 0.02 0.04 
  
  
  
  
  
  
Table 3. Cover fractions derived from MESMA grouped by the 
three main vegetation covers in the study area: mature forest, 
degraded forest and pine plantations. 
The table 2 shows the total species distribution area obtained 
for each species in the entire study area after mesmal and 
mesma2. Although E. arborea seems more spread than M. faya 
(it is found in a greater number of cells), if we take into 
account the sub-pixel cover fraction, the second one has a 
greater total cover area. Less abundant species were found to 
be L. novocanariensis, fern/herbaceous and P. radiata, by 
decreasing order. Percentiles 50" (Q2) and 75" (Q3) give an 
idea of overall pixel purity distribution. The degree of pixel 
purity appears to be particularly high in M. faya with respect to 
the rest. 
MESMA was less sensitive to pines than expected, although 
the remarkably higher proportion of shade in their presence 
made it easier to map them (figure 3c) Mesmal showed, in 
mature and degraded natural forests a mean shade fraction 
estimate of 0.13 and 0.11 respectively, whereas in pine 
plantations the mean shade fraction increased to 0.24, being 
above 0.6 in a 10% of the plantation area. Even though the 
dominant tree species in plantation areas of the study region is 
P. radiata, the presence of P. canariensis (for which no 
spectral signatures were available) could have contributed to 
the underestimation of pine cover fraction. E. arborea,