CONCLUSIONS
The methodological procedure used in this study, indicates the
usefulness of JERS-1 data, complementary to TM-Landsat
images to characterize areas covered by forests and savannas,
also allowing the definition of the spectral/textural space of
attributes (backscatter signal) occupied by each of these
vegetation units. The extensive field work to collect biomass
data and to define the physiognomy and structure of each
vegetation type allows us to better understand the significance
and behavior of the radar signals, confirming also the point of
saturation at the connection between o^ and biomass values. To
demonstrate the usefulness of the joint use of data from these
two sensor types, the Figure 7 present a section of the contact
zone between forest and savanna mapped, associated with
biomass intervals.
ACKNOWLEDGMENT
The authors acknowledge FAPESP - Fundagdo de Amparo à
Pesquisa do Estado de Sáo Paulo (process number 1997/0943-
8) Prefecture of the Municipality Alto Alegre and Roraima
State Government, for their technical and logistical support, and
also to Mr. Haron Abrahim Magalháes Xaud, researcher at
EMBRAPA-RR and to Mr. Osmarino Monteiro, botanist
assistent at INPA (National Institute for Amazonian Research).
REFERENCES
Brown, S.; Gillespie, A. J. R.; Lugo, A., 1989. Biomass
estimation methods for tropical forests with applications to
forest inventory data. Forest Science, 35(4), pp. 881-902.
Instituto Nacional de Pesquisas Espaciais - INPE, 1997. Manual
do usuário do SPRING: release 2.0.4. [online]. Divisäo de
Processamento de Imagens DPI/INPE.
<http://www.dpi.inpe.br/spring/usuario/indice.htm>.
Rosenqvist, A., 1997. Analysis of the backscatter characteristic
of rubber, oil palm and irrigated rice in multi-band polarimetric
synthetic aperture radar imagery. Thesis submitted to the
Institute of Industrial Science University of Tokyo. 114 p.
Uhl, C.; Buschbacher, R.; Serrdo, E.A.S., 1988. Abandoned
pasture in eastern Amazonia. I: pattern of plant succession.
Journal of Ecology, 76, pp. 663-681.
Xaud, M.R. 1998. Abordagem multisensor (TM/Landsat e
SAR/JERS) na caracterizagdo da cobertura vegetal e
distribuicáo de fitomassa em áreas de contato floresta/savana no
Estado de Roraima - Brasil. Sáo José dos Campos. Dissertagáo
de Mestrado em Sensoriamento Remoto, Instituto Nacional de
Pesquisas Espaciais. 111 p.
BN Primary forest
(194.71 + 32.99 ton/ha)
Secondary forest
(47.06 + 9.44 ton'ha)
EN Savanna woodland
(20.15 = 0.58 ton'ha)
Parkland savanna
(7.28 + 3.33 ton/ha)
Savanna grassland - dry
(4.86 = 2.03 ton'ha)
Savanna grassland - wet
{4.86 = 2.03 won'ha)
Pasture
Bare soil
BE Water
Unclassified
[]
W 61" 14^ 4" -——cócÓ[x-— —8$— ZB
Figure 7 - Map of biomass distribution according to vegetation units at a partial section of Alto Alegre region (Roraima State).
(Modified from Xaud, 1998).
