@Article{BreunigGaSiSaDeCh:2021:AsEfSp,
author = "Breunig, F{\'a}bio Marcelo and Galv{\~a}o, L{\^e}nio Soares and
Silva, Ricardo Dal'Agnol da and Santi, Ant{\^o}nio Luiz and Della
Flora, Diandra Pinto and Chen, Shuisen",
affiliation = "{Universidade Federal de Santa Maria (UFSM)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Universidade Federal de Santa
Maria (UFSM)} and {Universidade Federal da Grande Dourados (UFGD)}
and {Guangdong Engineering Technology Center for Remote Sensing
Big Data Application}",
title = "Assessing the effect of spatial resolution on the delineation of
management zones for smallholder farming in southern Brazil",
journal = "Remote Sensing Applications: Society and Environment",
year = "2021",
volume = "19",
pages = "e100325",
month = "Aug.",
keywords = "Cover crops, UAV, PlanetScope, OLI/Landsat-8, Agriculture.",
abstract = "Remote sensing estimates of cover-crop aboveground biomass (AGB)
have been used to delineate management zones for smallholder
farming in southern Brazil. In this study, we investigated the
spatial resolution influence on the AGB estimates of rye,
calculated from regression relationships with the Normalized
Difference Vegetation Index (NDVI), and on the subsequent
delineation of management zones using the Management Zone Analyst
(MZA) software. Data acquired by an Unmanned Aerial Vehicle (UAV)
Parrot Sequoia camera (0.20 m spatial resolution) in Brazil were
compared with observations from the PlanetScope (PS) satellite
constellation (3 m) and the Operational Land Imager
(OLI)/Landsat-8 (30 m). A three-endmember mixture model (green
vegetation, soil, and shadow) was applied to surface reflectance
data of these instruments for evaluating the cover-crop
development at two dates in August 2017. Because of the
differences in the technical specifications of the sensors, we
resampled the UAV dataset into four levels of spatial resolution
(1, 3, 10, and 30 m). Using the UAV map (0.20 m) as a reference,
we obtained confusion matrices for the original and resampled
data. The results showed that the increasing amounts of rye AGB
from the beginning to the end of August promoted significant
changes in surface reflectance and in soil-green vegetation
fractions calculated at variable spatial resolution. The
performance of the regression models to estimate cover-crop AGB
was approximately similar in the transition from the sub-metric
(0.20 m) to the metric (3 m) spatial resolutions, or from the UAV
camera to the PS data. For all datasets, the MZA detected two
management zones with zone 2 having higher cover-crop AGB than
zone 1. When compared to the UAV management zone map (reference),
the PS map had a moderate-to-substantial agreement, while the
OLI/Landsat-8 map had a fair-to-moderate concordance. Substantial
agreements with the reference map were observed at simulated 1 m
and 3 m data, as indicated by Kappa coefficients of 0.73 and 0.63
and overall accuracies of 86.40% and 81.40%, respectively. We
conclude that the 3 m spatial resolution data of the PS comprise
an alternative to delineate management zones for smallholder
farming in southern Brazil when compared to the very-high spatial
resolution observations of the UAV cameras.",
doi = "10.1016/j.rsase.2020.100325",
url = "http://dx.doi.org/10.1016/j.rsase.2020.100325",
issn = "2352-9385",
language = "en",
targetfile = "breunig_assessing.pdf",
urlaccessdate = "12 maio 2024"
}