roughness. With the end of the reproduction stage, several 
bamboo species are characterized by a massive mortality of 
population (Janzen, 1976), as observed in the dominant PEI 
species, and the results are extensive clearings with a large 
volume of dry biomass. Being so, the senescence period can be 
clearly identified by very clear tones due to the dominance of 
dry materials. 
With the mass mortality of bamboo populations, many of these 
areas within the PEI are colonized again by other bamboo 
species, restarting the dominance cycle. In the area under study, 
two bamboo species predominate: Guadua tagoara (Nees) 
Kunth (popularly known as taquaruqu) and Chusquea oxylepis 
(Hack.) Ekman (popularly known as criciuma). Both species 
have associated occurrences at several points within PEI. G. 
tagoara presents characteristically developed trunks which use 
thorns to climb arboreal individuals and to establish itself at the 
forest canopy, while C. oxylepis, with a similar structure as a 
climbing plant, forms a closed cover over the canopy. In spite 
of the distinct strategies for its dominance, both species 
originate a similar structural pattern, characterized by a 
discontinuous canopy, low density of arboreal individuals of 
medium and large size. Additionally, the superposition of the 
reproduction cycles of these species masks its individual 
characteristics in the image. In May 2006, when the QuickBird 
image was taken, the populations of taquarugu from the area 
under study were at the end of the reproduction cycle, while 
this time was the height of the reproduction period for criciuma. 
The structural similarity of vegetation together with the 
simultaneous flourishing of these species, makes it difficult to 
establish distinct patterns for them on a QuickBird scene. 
The map of land cover generated from the visual interpretation 
of the QuickBird image (Kappa = 0.85) allows the evaluation of 
class extension, which forms a mosaic composed by vegetation 
in different succession stages, and many of them have a 
dominant occurrence of bamboos at different life phases. In the 
Amazon, each internally synchronized bamboo population, 
occupies extensive areas between 10 2 to 10 4 km 2 , which can be 
detected with TM-Landsat and MODIS (Nelson et al, 2006) 
images during the massive mortality of these sections. At PEI 
however sections of bamboo dominance occupy areas between 
0.15 to 0.30 km 2 , which cannot be identified with medium 
resolution sensors (Araujo et al, 2005), independently of its 
phenologic stage. 
From the land cover map it is also possible to evaluate the 
extension of the bamboo occupation at Intervales. In the region 
analyzed, despite the class forest still covers 36% of the total 
area, those classes with bamboo dominance come up to 21%. 
The class with spaced bamboo sections, due to the border 
contact with bamboo dominance, besides the extremely 
aggressive habits of these species, has a high chance to be 
progressively converted to the class secondary succession with 
bamboos. With this inclusion, the percentage of areas with 
bamboo is also 36%. A similar inference can be made for the 
class advanced secondary succession covering 21% of the area 
under consideration. 
Despite the relative restricted number of bands at the QuickBird 
image, when compared with other products of remote sensing, 
the analysis of the spectral responses from different targets 
evidences the discrimination between classes of interest, as 
observed at Figure 5. Generally the classes present a typical 
spectral behavior of vegetation, with low values at bands 1, 2 
and 3, referring to the visible section of the electromagnetic 
spectrum and high values at band 4, corresponding to the near- 
infrared section, which is more adequate for the discrimination 
of these forest targets. Similarly to what was observed in other 
scales of work (Nelson et al, 2006; Mendoza et ai. 2004), the 
layer formed by bamboo leaves in the forest canopy reflects 
more intensively, especially when considering the near-infrared 
band. We emphasize again the difficulty to discriminate the 
class with bamboo dominance in growing stage, which has a 
very similar spectral response as the class advanced secondary 
succession, despite the floristic and structural differences. 
The adequate mapping of this secondary succession with 
bamboo dominance in vegetative stage and the understanding of 
the phenologic aspects of the dominant bamboo species, is an 
important aspect for studies of forest dynamics. These factors 
allow the planning to open new clearings, which is of 
fundamental importance to understand the landscape of this 
region. In this case, the use of a temporal series is fundamental 
for such studies, due to a very specific dynamic of this forest 
formation. 
Figure 6a illustrates a section of bamboo at reproductive stage, 
mapped with aerial photography and the corresponding 
QuickBird image. The aerial photography was taken in 2000, 
probably at the growing stage. Figure 6b shows part of the 
phenologic cycle from the bamboo at an advanced 
decomposition stage in 2006. 
(a) 
(b) 
Figure 6. Examples of the phenologic phases of bamboo at 
aerial photography from 2000 (1) and QuickBird image from 
2006 (2): [VB] bamboo during vegetative stage, [RB] bamboo 
during reproductive stage and [SB] bamboo after senescent 
stage. 
In spite of a similar resolution, the QuickBird images have 
advantages when compared to aerial photographs, even 
considering only the visual interpretation. At the satellite image, 
the tonal variations in the near-infrared band, allows the 
discrimination of different phenologic phases of the bamboo 
that are not evident in the aerial photographs, even if the 
bamboo is at the early senescent stage. The temporal analysis 
using QuickBird images is of promising importance in this case 
to characterize the life cycles of these dominant bamboos 
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