@Article{Almeida-FoShim:2002:DiPrLa,
author = "Almeida-Filho, Raimundo and Shimabukuro, Yosio Edemir",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Digital processing of a Landsat-TM time series for mapping and
monitoring degraded areas caused by independent gold miners,
Roraima State, Brazilian Amazon",
journal = "Remote Sensing of Environment",
year = "2002",
volume = "79",
number = "1",
pages = "42--50",
month = "Jan.",
keywords = "geologia, Amaz{\^o}nia (Regi{\~a}o), mapeador tem{\'a}tico
(Landsat), an{\'a}lise de series temporais, mapeamento,
monitoramento ambiental, exatid{\~a}o, degrada{\c{c}}{\~a}o,
thematic mappers (Landsat), time series analysis, environmental
monitoring, accuracy, degradation.",
abstract = "A 12-year Landsat-Thematic Mapper (TM)time series (1987-1999) was
used for mapping and monitoring evolution of degraded areas caused
by independent miners ({"}garimpeiros{"})in the search for gold
and diamond. Discrimination of target areas was achieved through
third principal component images, due to their best enhancement of
bare soil areas relative to the surrounding savanna vegetated
terrain. A postclassification approach, based on image
segmentation/region classification techniques, was used to map
degraded areas. This procedure allowed to save time and to curtail
inherent subjectivity commonly involved in visual interpretation,
producing accurate land-cover change maps. According to these
maps. degraded areas comprise 94.4 ha in 1987. 286.4 ha in 1991,
and 404.4 ha in 1994. After {"}garimpeiros{"} abandoned the region
sometime prior to 1994, vegetation soon started recovering mined
areas as shown in images acquired in 1995, 1996, and 1999.
According to these images, degraded areas decreased to 311.2,
283.7, and 246.2 ha, respectively. Data also indicate that
vegetation regrowth is faster near the border of degraded areas,
and becomes slower to the center of these areas, where damage
process is more intense. Based on the satellite images-derived
regrowth rates. it is possible to infer that degraded areas would
not be entirely recovered by vegetation by the year 2019.",
doi = "10.1016/S0034-4257(01)00237-1",
url = "http://dx.doi.org/10.1016/S0034-4257(01)00237-1",
issn = "0034-4257",
label = "9896",
language = "en",
targetfile = "1-s2.0-S0034425701002371-main.pdf",
urlaccessdate = "28 abr. 2024"
}