@PhDThesis{Tôsto:2021:BaNiBa,
author = "T{\^o}sto, Karina Lima",
title = "Balan{\c{c}}o do nitrog{\^e}nio na Bacia do Alto Paraguai",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2021",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2021-05-20",
keywords = "nitrog{\^e}nio, uso do solo, efici{\^e}ncia no uso do
nitrog{\^e}nio, agropecu{\'a}ria, biogeoqu{\'{\i}}mica
ambiental, nitrogen, land use, nitrogen use efficiency,
agriculture, environmental biogeochemical.",
abstract = "O nitrog{\^e}nio (N) {\'e} um elemento necess{\'a}rio para
todos os seres vivos e desempenha papel cr{\'{\i}}tico para a
produ{\c{c}}{\~a}o prim{\'a}ria. Em decorr{\^e}ncia das
atividades antr{\'o}picas, t{\^e}m ocorrido intensas
mudan{\c{c}}as na disponibiliza{\c{c}}{\~a}o desse nutriente e
na sua ciclagem no ambiente a n{\'{\i}}vel global. O N
representa um elo comum para garantia de diversas metas previstas
nos Objetivos de Desenvolvimento Sustent{\'a}vel, devido {\`a}s
m{\'u}ltiplas conex{\~o}es existentes entre a
produ{\c{c}}{\~a}o de alimentos, fibras e energia para atender
as crescentes demandas humanas, que deve ocorrer garantindo o
equil{\'{\i}}brio ambiental e a sustentabilidade
socioecon{\^o}mica. A Bacia do Alto Paraguai (BAP) constitui uma
{\'a}rea de conflito entre a expans{\~a}o das atividades
agropecu{\'a}rias nas partes altas da bacia, e a
conserva{\c{c}}{\~a}o de ecossistemas a jusante que formam a
plan{\'{\i}}cie do Pantanal Mato-grossense, importante {\'a}rea
{\'u}mida e Patrim{\^o}nio Nacional. Neste trabalho, s{\~a}o
investigadas as rela{\c{c}}{\~o}es entre a expans{\~a}o e
intensifica{\c{c}}{\~a}o das atividades agropecu{\'a}rias nos
fluxos de N nas lavouras e pastagens, no per{\'{\i}}odo de 2001
a 2017. Os principais fluxos de N foram identificados e
quantificados, sendo consideradas as entradas
(deposi{\c{c}}{\~a}o atmosf{\'e}rica, fixa{\c{c}}{\~a}o
biol{\'o}gica, aduba{\c{c}}{\~a}o org{\^a}nica e fertilizantes
sint{\'e}ticos), sa{\'{\i}}das (produtos colhidos e
produ{\c{c}}{\~a}o de carne e leite) e perdas potenciais
(emiss{\~o}es gasosas, lixivia{\c{c}}{\~a}o e eros{\~a}o do
solo). Na agricultura, as entradas de N foram estimadas em 197,6
kg N ha-1ano-1 em 2001 e 269,8 kg N ha-1ano-1 em 2017, um aumento
de quase 40%. A fixa{\c{c}}{\~a}o biol{\'o}gica representa a
principal fonte de N para a bacia, contudo, tem ocorrido
consider{\'a}vel aumento nas taxas de aplica{\c{c}}{\~a}o de
fertilizantes sint{\'e}ticos, contribuindo para o aumento da
produtividade, principalmente do milho. Observou-se aumento na
produtividade geral da agricultura, representada pelo aumento nas
sa{\'{\i}}das de N atrav{\'e}s dos produtos colhidos, estimadas
em 204,5 kg N ha-1ano-1 em 2001 e em 247,8 kg N ha- 1ano- 1 em
2017. As perdas potenciais de N nesses sistemas destacam-se pelo
maior aumento registrado dos fluxos, superior a 70%, estimadas em
28,8 kg N ha-1ano-1 em 2001 e 45,6 kg N ha-1ano-1 em 2017. O
balan{\c{c}}o do N, estimado pela diferen{\c{c}}a entre as
entradas e o somat{\'o}rio das sa{\'{\i}}das e perdas
potenciais, mostra um d{\'e}ficit anual de cerca de 25,0 kg N ha-
1ano-1. Em rela{\c{c}}{\~a}o a Efici{\^e}ncia do Uso de
Nitrog{\^e}nio (NUE), a persist{\^e}ncia de valores
pr{\'o}ximos ou superiores a 1 durante todo o per{\'{\i}}odo
indicam a suscetibilidade dos solos agr{\'{\i}}colas {\`a}
degrada{\c{c}}{\~a}o pela reposi{\c{c}}{\~a}o insuficiente do
N removido. Em pastagens, as entradas m{\'e}dias foram estimadas
em 38,2 kg N ha-1ano-1 durante todo o per{\'{\i}}odo.
Observou-se o aumento em mais de 70% das sa{\'{\i}}das
atrav{\'e}s da produ{\c{c}}{\~a}o carne e leite, estimadas em
1,9 kg N ha- 1ano-1 em 2001 e 3,3 kg N ha-1ano-1 em 2017,
evidenciando o ganho na produtividade desses sistemas. As perdas
de N em pastagens s{\~a}o altas, estimadas em 13,0 kg N
ha-1ano-1, em m{\'e}dia. Valores positivos para o balan{\c{c}}o
durante todos os anos indicam o ac{\'u}mulo de N, cerca de 9,3 kg
N ha-1ano-1. A NUE nas pastagens {\'e} ainda muito baixa,
n{\~a}o ultrapassando o valor de 0,2. ABSTRACT: Nitrogen (N) is
an important element for all living beings and plays a critical
role in primary production. As a result of human activities, there
have been intense changes in the availability of this nutrient and
its cycling in the environment at a global level. N represents a
common link to guarantee several goals foreseen in the Sustainable
Development Goals, due to the multiple existing connections among
the production of food, fibers, and energy to meet the growing
human demands, which must occur to guarantee the environmental
balance and socioeconomic sustainability. The Upper Paraguay Basin
(BAP) constitutes an area of conflict between agricultural
expansion in the upper areas and conservation of downstream
ecosystems that form Pantanal wetland, a National Heritage. In
this work, relationships between the expansion and intensification
of agricultural activities in N fluxes in crops and pastures,
between 2001 and 2017, are investigated. The main N fluxes were
identified and quantified, considering inputs (atmospheric
deposition, biological fixation, organic manure, and synthetic
fertilizers), outputs (harvested products and meat and milk
production), and potential losses (gaseous emissions, leaching,
and soil erosion). In agriculture, N inputs were estimated at
197.6 kg N ha1 yr-1 in 2001 and 269.8 kg N ha-1 yr-1 in 2017, an
increase of almost 40%. The biological fixation represents the
main source of N for the basin, however, there has been a
considerable increase in the rates of application of synthetic
fertilizers, contributing to the increase in productivity, mainly
for maize. An increase in the general productivity of agriculture
was observed, represented by the increase in N outputs through
harvested products, estimated at 204.5 kg N ha-1yr-1 in 2001 and
247.8 kg N ha- 1yr-1 in 2017. Potential losses of N in these
systems are highlighted by the largest recorded increase, up to
70%, estimated at 28.8 kg N ha-1yr-1 in 2001 and 45.6 kg N
ha-1yr-1 in 2017. Nitrogen balance, calculated as the difference
between N inputs and the sum of the outputs and potential losses,
shows an annual deficit of about 25,0 kg N ha-1yr-1. Considering
the Nitrogen Use Efficiency indicator (NUE), the persistence of
values close to or greater than 1 throughout the period indicates
the susceptibility of productive soils to degradation due to
insufficient replacement of the N removed. In pasturelands,
average inputs were estimated at 38,2 kg N ha-1yr-1 during the
period. N outputs increased by 70% through milk and meat
production, estimated at 1,9 kg N ha- 1yr-1 in 2001 and 3,3 kg N
ha- 1ano-1 in 2017, evidencing gain in productivity in these
systems. N losses in pastures were high, estimated in 13.0 kg N
ha-1yr-1, on average. Positive values for N balance during all the
years indicate N accumulation, about 9.3 kg N ha-1yr-1. NUE on
pastures is still low, not exceeding 0.2.",
committee = "Giarolla, Ang{\'e}lica (presidente) and Ometto, Jean Pierre Henry
Balbaud (orientador) and Forti, Maria Cristina (orientadora) and
Pacheco, Felipe Siqueira (orientador) and Martinelli, Luiz
Ant{\^o}nio and Galdino, Sergio",
englishtitle = "Nitrogen budget in the Upper Paraguay Basin",
language = "pt",
pages = "128",
ibi = "8JMKD3MGP3W34T/44U3H55",
url = "http://urlib.net/ibi/8JMKD3MGP3W34T/44U3H55",
targetfile = "publicacao.pdf",
urlaccessdate = "10 maio 2024"
}