THE USE OF REMOTE SENSING AS A FORM OF EVIDENCE OF THE USE
OF SOIL WETLANDS IN THE REGION OF THE UPPER COURSE
UBERABINHA IN UBERABA – MG.¹
Rafael Tiago dos Santos Silva. Student of Geography. Federal University of Triângulo Mineiro
(UFTM), Uberaba/MG/Brazil. Email:rafatiago@gmail.com²
Ângela Maria Soares. Teacher of Geography. Federal University of Triângulo Mineiro (UFTM),
Uberaba/MG/Brazil. Email:angelamsoares@gmail.com³
The work presented here seeks to accomplish an upgrade use mapping and land cover in the
basin area of the upper and middle course of the Uberabinha, giving priority to the development
of the occupation of wet systems by human action in increasing development. The basin is located
between the cities of Uberlandia and Uberaba, both in Triângulo Mineiro, a region of Minas
Gerais, Brazil and their study is of great importance for public supply in the city of Uberlandia
with over six hundred thousand inhabitants. The occupation of the basin area is relatively recent,
dating from the late twentieth century, when southern farmers came to occupy the land of the
savanna ecosystem using techniques of "modern agriculture". The use of remote sensing from
satellite images is necessary to highlight the recent developments in these areas through
techniques of image processing where the level of reflectance indicates the location of wet fields
and also allows a production of a map of the use and occupation soil in the area of the basin. The
technique minimizes a noise component introduced into the scene and enhances the power of the
target discrimination, and create an image derived from it were regions of interest (ROIs)
represent the different modes of use and occupancy of the wetlands. We used images from
LANDSAT 5 TM for the mapping and field control. The reduction of water infiltration in soil is
contributing to reducing the amount of water that recharges the aquifers annually. Based on the
results obtained from studies conducted through 2006, we noticed that human activities are
depriving these wetlands from the tops of plateaus that were being incorporated into production
and that constant monitoring is needed to find ways to mitigate and control the progress of
activities in these areas that should be preserved since they are a major source of supply for a
saturated zone and groundwater recharge that its full will only be achieved with the adoption of
sustainable management practices, soil and vegetation emphasizing a maximization of the volume
of recharge water in aquifers that enables a exploitation of groundwater, and maintains the base
flow of surface drainage.
Thematic classification: Geomorphic Challenges for the 21st Century.
¹ Research Project with financing from Foundation for Research Support of Minas Gerais (FAPEMIG);
² Scientific Initiation Scholarship Foundation for Research Support of Minas Gerais (FAPEMIG); Participation in this event
made possible by the financial support of the International Geographical Union (IGU);
³ Professor, Department of Geography, Federal University of Minas Gerais (UFTM).
Introduction
Uberabinha the Upper Basin is the source used for public supply in the cities of Uberlandia and
Uberaba, in Minas Gerais, Brazil. It is located in the middle region of Minas Gerais, upstream of the
city of Uberlandia. This basin covers the municipalities of Uberaba, in the northern portion and the
portion of the southeastern city of Uberlandia. (Image 1).
Image 1: Research Area Location Map in the Upper Uberabinha.
Its waters are also used for agricultural production and industrial processes of commodity like soy,
alcohol, corn, sugar, poultry, cattle, pigs, among others. In the area there are mining from 1950 to
explore clay and subsequently limestone.
The Upper Basin Uberabinha has high water storage capacity due to the large soil thickness and relief
features, especially in the plateau portion. The natural features affect the characteristics of the base
flow, which in turn determines the river flow regularity from the river Uberabinha. It is possible that
the dynamics of surface and subsurface water are being modified by the intense use and land cover on
the upper course of the river Uberabinha, the amount of the Water Treatment Station of Sucupira,
which can have negative consequences for the recharging of its groundwater saturated zone.
This situation interferes with the quantity of water intended for human consumption, especially the
residents of the city of Uberlândia (MG), which depend entirely on this source, and the inhabitants of
the city of Uberaba, which also indirectly depend on the source, is the implementation of water Rio
Claro, adjacent to the river basin Uberabinha, is the preservation of the headwaters of the Rio Uberaba,
also born in Uberaba, Uberlandia plateau.
In recent decades, this basin hydrographic has gone through intense changes related to the use and
occupation of soil. According to Soares (2008:19), "until the year 1970 the Upper Uberabinha Basin, as
well as the cerrados of central Brazil, were in balance. There was a perfect compensation between what
is produced and what was spent by the various players that made up the landscape. The evolution of
landscapes happened naturally. "The occupation of the area is initially associated with the extensive
breeding of cattle and the clay exploitation from 1950. During this period the natural vegetation of the
Upper Uberabinha was the Cerrado in its various phytophysiognomies.
Soares (2008) notes that after 1970, with the arrival of silviculture and after that, the monoculture, the
Upper Uberabinha began to incorporate techniques of "modern" agriculture. The intensive use of
mechanization, acidity correction, chemical fertilization, heavy use of agrotoxics and other practices
will result in the disruption of the dynamic equilibrium and some geomorphological and hydrological
processes were initiated and / or accented.
Schneider (1996) has highlighted the environmental degradation caused by the use of this area and
post-1970 occupation. According to the author, tests performed on water samples of the Uberabinha in
1986 and 1987, showed the presence of pesticide residues in different parts of river. In addition to
water contamination and degradation of wet systems, the basin the Upper Uberabinha has been the
scene of a number of other processes caused by human action intense and badly planned.
The Upper Uberabinha basin area is around 55,279.09 ha. In 1964 basin hydromorphic areas totaled
16,905.30 ha total area of 30.58 %. In 2006 the fields hydromorphic area measuring 13,078.58 ha,
about 23.60 % of the total area (Table 1). During this period (1964 - 2006) hydromorphic 3,826.72 ha,
6.98 % of the total area of the basin the Upper Uberabinha, were incorporated into the production area
(Soares, 2008). This process of incorporation of systems to the wet production area was largely
discussed in Schneider (1996) and Soares (2002, 2008). These surveys of wetlands occupied the basins
of the Uberabinha, crosses were made by using the survey maps, satellite images and aerial
photographs.
In this research we attempted to retrieve and update these surveys using Geographic Information
System and most modern techniques of GEOPROCESSING. The use of remote sensing favored the
interpretation of the geomorphology of the study area. According Florenzano (2008),
geomorphological science is one of the most benefited by the remote sensing technology advancement ,
due to the fact that the relief is generally well highlighted in aerial photographs and satellite images, as
well as the availability of data that enable the multitemporal study of morphodynamic processes.
The research main goal is to produce an evolution map of the use and occupation of soil in the basin of
the upper river Uberabinha using supervised classification techniques. This technique is used when you
have some prior knowledge about the classes in the interested images, which will allow the analyst to
set on the same classes sample areas. These sampling areas are used by classification algorithms to
identify the points in the image representing the classes (ROIs).
Main Argument
To perform the mapping of wetlands and land use and soil, was performed using the materials:
 IBGE topographical maps, sheet: Miraporanga (Folha SE-22-ZD-III, MI 2488) and Nova Ponte
(Folha SE-23-YCI, MI 2489);
 ENVI software ArcMap 9.3 and 4.7;
 Satellite Image provided by INPE, image: Landsat 5 TM sensor Thematic Mapper (TM) Image:
Orbit 221/73 with spatial resolution of 30 meters and dated August 8, 2011.
 Field work carried out weekly during 2010 and 2011.
Initially there was a bibliographic survey on the data regarding the watershed study area and verified
the need to elaborate a base map of the basin using the IBGE topographic maps in digital format,
containing the limits of the interested area and drainage subsequently rectified to 1:25,000 scale. On
this base map already scanned and georeferenced in ArcMap 9.3 software was subsequently drawn map
of location, slope, hypsometric and land use.
With the aid of techniques and features of ENVI 4.7 software were the following operations:
Visualization the Image: Import image in TIF format to the spectral composition of images and easy
viewing of the scene, the cut is made in the area of interest (upper course of the river basin Uberabinha)
Spatial Subset through the tool and subsequently performed GEOTIF export to the format.
Color Composite Generation of: For a better image visualization and to gain a greater power of the
targets discrimination was performed linear contrast of the bands 5, 4 and 3, and then color composite
was generated 5r4g3b.
The bands 5, 4 and 3 were chosen, since the characteristics of spectral bands and width of the
wavelength reflectance attend the requirements of water bodies and wetlands.
The band has five wavelength of 1.55 to 1.75 (µm), displays sensitivity to the humidity level of plants,
serving to experience stress in vegetation caused by water imbalance. Already the band has 4
wavelength of 0.76 to 0.90 (µm) and has a great ability to capture the corpses of water absorb much
energy in this band and are dark, allowing the mapping of the drainage network and design of bodies
water. The green vegetation, dense and uniform, it reflects a lot of energy in this band, appearing in the
images clear. Presents sensitivity to the morphology of the terrain, allowing to obtain information about
geomorphology, soils and geology. And finally the band 3, which presents the long waves of 0.63 to
0.69 (µm), operates in more emphasis on green vegetation, dense and uniform, which has large
absorption, getting dark, allowing good contrast between the areas occupied by vegetation. Allows the
mapping of drainage through the forest gallery and viewing slot of the courses of rivers in areas with
little vegetation.
Generation of the Map: The current images provided by the INPE, are already being distributed
georeferenced in UTM WGS-84 format and is not necessary geometric correction. The digital image
processing to generate the map of wetlands and land use and soil are carried out using the tool ROIs
(Region of Interest). The areas representing the desired class are selected and samples from them, you
can get a description of the classes of interest. These, then classes are considered to a particular region
and not for mapping classes of isolated pixels (Ribeiro, Center, and BAHR, 2002). The ratings from
regions of interest are necessary for differentiation of classes of vegetation and soil use and occupation.
After defining the categories of land use and vegetation cover and visual interpretation of the image on
the screen, the final map was generated in ArcMap 9.3 software, which were inserted cartographic
conventions such as title, author, guide, coordinates, scale and source information about dates.
The development of the Land Use Map in the Upper Uberabinha, using images of 2011, showed that
the area still has passed through important transformations, especially the reduction of the planted
pastures, increase in areas with annual crops of sugarcane and insertion sugarcane. Schneider (1996)
and Soares (2008) have identified wetlands for agriculture that have been incorporated since 1964,
when closed had not been used for agricultural production (Table 1). As the authors did surveys at
different times, using remote sensing and GEOPROCESSING available at the time.
Table 1 - Wetlands incorporated into the productive system in the period 1964 to 2006 in the Upper
Uberabinha - Uberaba / Uberlândia - MG.
Year of survey
Wetland area in (há)
Percentage in relation to
total area of the basin
1964
16,905.30
30.58 %
2006
13,078.58
23.60%
Source: Adapted from Schneider (1996) and Soares (2008).
With the advancement of these techniques, the results of this study show that even weakened and
incorporated into the productive system some wet fields the Upper Basin Uberabinha still have their
hydrological dynamics partially preserved (Image 2 and Table 2).
Image 2: Soil Use Map and the Upper Uberabinha Occupation.
Table 02: - Wetlands, 1964, 2006 and 2011 in the Upper Uberabinha - Uberaba / Uberlândia - MG.
Year of survey
Wetland area in (há)
Percentage in relation to
total area of the basin
1964
16,905.30
30,58 %
2006
13,078.58
23,60 %
2011
17,202.67
31,11 %
Source: Adapted from Soares (2008).
Conclusion
The data update on land use in the Upper Uberabinha, performed with the use of techniques of modern
remote sensing and geoprocessing, showed that the wet systems in the basin currently occupy larger
area than the raised by Soares (2008), when used images of 2006 and also when utilized aerial
photography from 1964.
The data collected should be analyzed taking into account the spatial resolution of the images used,
which have precisely one hundred feet. This can lead to variation in the percentage raised.
But even with this variation may be possible to highlight some important points. It is noticed that the
soil use in basin of the Upper Uberabinha interfered in any way the hydrological dynamic of the area,
reducing infiltration, characterizing wet systems occupied by agriculture, among others. But even
weakened and / or occupied by agriculture, the systems still have their wet hydrological dynamics
partially preserved.
This was verified in this mapping, when the techniques used have provided verification of the presence
of moisture on the surface where these systems were built that were wet for agriculture. This may also
be related to the drains closure done in most of the studied area.
References
FLORENZANO, T. G. Introdução à Geomorfologia. In: Geomorfologia conceitos e tecnologias
atuais. Teresa Galloti Florenzano (org). São Paulo: Oficina de Textos, 2008. p. 12-25.
RIBEIRO, S. R. A.; BÄHR, H. P.; CENTERO, J. S. Integração de imagens de satélite e dados
complementares para a delimitação de unidades de paisagem usando uma abordagem baseada em
regiões. Bol. Ciênc. Geod., Curitiba, v. 8, no 1, 2002. p.47-57.
SCHNEIDER, M. O. Bacia do rio Uberabinha: uso agrícola do solo e meio ambiente. Tese
(Doutorado em Geografia Física). FFCLH-USP. São Paulo, 1996.
SOARES, A. M. A bacia do Rio Claro: reflexos da ocupação antrópica. Dissertação (Mestrado em
Geografia). Uberlândia, 2002. Instituto de Geografia, Universidade Federal de Uberlândia.
SOARES, A. M. A dinâmica hidrológica na Bacia do Alto Uberabinha, Minas Gerais. Tese
(Doutorado em Geografia). Uberlândia, 2008. Instituto de Geografia, Universidade Federal de
Uberlândia.