@PhDThesis{Aguiar:2013:SéTeIm,
author = "Aguiar, Daniel Alves de",
title = "S{\'e}ries temporais de imagens MODIS para avalia{\c{c}}{\~a}o
de pastagens tropicais",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2013",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2013-09-24",
keywords = "EVI-2, intensifica{\c{c}}{\~a}o, degrada{\c{c}}{\~a}o,
pastagens tropicais, fotografias verticais, EVI-2, Livestock
intensification, grasslands degradation, tropical grasslands,
digital images.",
abstract = "A inexor{\'a}vel mudan{\c{c}}a na dieta alimentar dos
pa{\'{\i}}ses emergentes, projetada para os pr{\'o}ximos anos,
aumentar{\'a} o consumo global de prote{\'{\i}}na animal e
demandar{\'a} {\`a} pecu{\'a}ria brasileira uma resposta sobre
a oferta de carne bovina. Todavia, existem dois fatores que devem
associar o aumento da oferta de carne bovina exclusivamente {\`a}
melhoria na produtividade da pecu{\'a}ria: i) a
limita{\c{c}}{\~a}o da expans{\~a}o pecu{\'a}ria e
agr{\'{\i}}cola sobre a vegeta{\c{c}}{\~a}o nativa devido
{\`a}s metas assumidas pelo governo federal para a
redu{\c{c}}{\~a}o das taxas de desmatamento e das emiss{\~o}es
dos gases de efeito estufa; e ii) a competi{\c{c}}{\~a}o por
terras para a produ{\c{c}}{\~a}o de gr{\~a}os e de
biocombust{\'{\i}}veis. Nesse sentido, a avalia{\c{c}}{\~a}o
da qualidade das pastagens em escala regional {\'e} essencial,
pois oferece subs{\'{\i}}dios para direcionar as
pol{\'{\i}}ticas p{\'u}blicas de uso racional do
territ{\'o}rio com o intuito de aumentar a produtividade da
pecu{\'a}ria. A hip{\'o}tese deste trabalho {\'e} que as
imagens de sat{\'e}lites de observa{\c{c}}{\~a}o da Terra podem
ser empregadas para avaliar o processo de degrada{\c{c}}{\~a}o,
renova{\c{c}}{\~a}o/recupera{\c{c}}{\~a}o e reforma das
pastagens tropicais. Para testar essa hip{\'o}tese foram
realizadas duas campanhas de campo nas quais foram percorridos
aproximadamente 40 mil km em nove estados brasileiros. Para
caracteriza{\c{c}}{\~a}o das pastagens amostradas foram
realizadas medidas de par{\^a}metros biof{\'{\i}}sicos e
observa{\c{c}}{\~o}es acerca das pastagens, do manejo adotado e
das paisagens. Nas pastagens amostradas foram adquiridas
fotografias verticais, das quais foram extra{\'{\i}}das
fra{\c{c}}{\~o}es de cobertura da superf{\'{\i}}cie.
S{\'e}ries temporais de EVI-2/MODIS do per{\'{\i}}odo de 2000 a
2012 das pastagens amostradas foram avaliadas de acordo com um
protocolo elaborado com base em 7 m{\'e}tricas fenol{\'o}gicas,
14 crit{\'e}rios booleanos e 2 crit{\'e}rios num{\'e}ricos. A
base te{\'o}rica deste protocolo foi elaborada a partir de
entrevistas a produtores e especialistas em uma terceira campanha
de campo realizada no {\^a}mbito do Projeto Geodegrade. Os
resultados deste trabalho mostraram que as fra{\c{c}}{\~o}es de
cobertura da superf{\'{\i}}cie extra{\'{\i}}das de fotografias
verticais s{\~a}o indicadores objetivos das condi{\c{c}}{\~o}es
das pastagens, em especial a fra{\c{c}}{\~a}o n{\~a}o pastagem
(solo + serrapilheira), que se mostrou um excelente indicador do
est{\'a}dio de degrada{\c{c}}{\~a}o da pastagem. A an{\'a}lise
das s{\'e}ries temporais permitiu estimar os percentuais de
pastagens amostradas que passaram por algum tipo de
interven{\c{c}}{\~a}o e que estavam em processo de
degrada{\c{c}}{\~a}o biol{\'o}gica. Das 782 pastagens
amostradas, 26,6\% passaram por algum tipo de
interven{\c{c}}{\~a}o, 30,3\% estavam em processo de
degrada{\c{c}}{\~a}o biol{\'o}gica e 43,1\% n{\~a}o sofreram
nenhum tipo de interven{\c{c}}{\~a}o e n{\~a}o apresentaram
tend{\^e}ncia de redu{\c{c}}{\~a}o de biomassa no
per{\'{\i}}odo analisado. ABSTRACT: The inexorable diet change
in the emerging countries, projected for the coming years, will
significantly increase the global consumption of animal protein.
Therefore, it is expected that the Brazilian livestock production
should be prepared to answer for the increasing demand of beef.
However, there are two factors that must associate the increasing
beef supply exclusively to the improvement in livestock
productivity: i) no expansion of livestock and farming on native
vegetation due to the commitment of the Brazilian government to
reduce deforestation rates and greenhouse gases emissions, and ii)
continued conversion from pasture land to grain and biofuel
production. Consequently, the evaluation of pasture quality on a
regional scale is important information to orient public policies
to a rational land use strategy directed to improve livestock
productivity. The hypothesis is that satellites images can be used
to evaluate the processes of degradation, restoration and
renovation of tropical pastures. To test this hypothesis two field
campaigns were performed covering a trajectory of approximately
40,000 km throughout nine states. To characterize the sampled
pastures biophysical parameters were measured, and observations
about the pastures, the adopted management and the landscape were
performed. Vertical photographs were acquired for each sampled
pasture to estimate three different fractions of surface coverage.
Each sampled pasture was evaluated using time series of
EVI-2/MODIS images, from the period 2000-2012, according to a
protocol based on seven phenological metrics, 14 Boolean criteria
and two numerical criteria. The theoretical basis of this protocol
was derived from interviews with producers and livestock experts
during a third field campaign. The results of this work showed
that the fraction of surface coverage, extracted from the vertical
photographs, was a good indicator of pasture degradation,
especially the no-green pasture fraction (soil and litter). The
analysis of the time series of MODIS images provided valuable
historical information on the type of intervention and on the
biological degradation process of the sampled pastures. Of the 782
sampled pastures, 26.6\% experienced some type of intervention,
30.3\% were under biological degradation, and 43.1\% presented
neither intervention nor trend of biomass decrease during the
analyzed period.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)}",
committee = "Formaggio, Antonio Roberto (Presidente) and Rudorff, Bernardo
Friedrich Theodor (Orientador) and Adami, Marcos and Dias Filho,
Moacyr Bernardino and Nogueira, Sandra Furlan",
copyholder = "SID/SCD",
englishtitle = "MODIS time series for evaluation of tropical grasslands",
language = "pt",
pages = "167",
ibi = "8JMKD3MGP7W/3ENND62",
url = "http://urlib.net/ibi/8JMKD3MGP7W/3ENND62",
targetfile = "publicacao.pdf",
urlaccessdate = "2024, May 05"
}