exercise six - analyzing land use and sustainability

Exercise 6

Analyzing land use and sustainability in

Brazil

In this exercise, you will use a public domain spatial data portal from a national government agency to assess the spatial pattern of land use and deforestation in Rondônia, Brazil. You will combine the data with Landsat imagery from an international portal to more fully understand the situation from a temporal and geographic perspective.

Some of the data you will interrogate to investigate land use in Brazil

Exercises for The GIS Guide to Public Domain Data

Context

Approximately 30 percent of the world’s tropical forests lie within the country of Brazil. These forests are one of the world’s great natural resources and help to regulate the global carbon cycle, climate, as well as provide habitat for thousands of animals, plants, and native human populations. Due to growing population and demand for land and other natural resources, the Brazilian rainforest, like other major ecoregions of the world, faces development pressure. Indeed, the deforestation resulting from the spread of agriculture and conversion of forest areas to urban use has been one of the most widely discussed and publicized land use change phenomena of recent times.

The estimated average deforestation rate from 1978 to 1988 alone was 15,000 square kilometers per year. Systematic deforestation begins as roadways are built, and fans out from there to create a pattern that looks like a feather, or a fishbone. As the pattern of land use change at both the regional and local levels is geographic in nature, GIS is a suitable tool to help understand the impacts of deforestation and to plan for the future.

Problem

After reading for years about development and deforestation in Brazil, you decide to use your new-found GIS skills to investigate the situation for yourself and look at the problem spatially. Your goal is assess the pattern and reasons for development in one of the most widely known part of the rainforest, the state of Rondônia, Brazil. You will consider the following in your assessment of land use and deforestation in Rondônia: Vegetation

Biomes

General land characteristics, including

transportation and physical features

Soils

Potential agriculture

Administrative political divisions

Resources Skills Required

Downloading and formatting data from a federal national public domain data source and an international data source for use in a GIS

Downloading and formatting Landsat satellite imagery data for use in a GIS

Analyzing spatial data in a problem-solving environment

Integrating multiple sources into GIS-based analysis

TIME This exercise contains fifty-two questions and will require two to four hours to complete. SOFTWARE ArcGIS 10.0 or later, from Esri.

Work package 1: Managing and accessing your data Steps 1 - 6

Create a folder on your computer or network to store data. Make sure the folder has a descriptive name (so you can easily recall its contents) and choose a name without spaces to avoid problems in ArcGIS.

1) Access IBGE Access the Brazil Institute for Geography and Statistics (Instituto Brasileiro de Geografia e Estatistíca [IBGE]) site at http://www.ibge.gov.br/home/. If you prefer to examine the front page in English, see http://www.ibge.gov.br/english/.

1.1) What is the IBGE? 1.2) Which government agencies in the United States serve similar functions to the IBGE?

2) Locate Rondônia

On the left side, under Database, select Estadoes@ (States@). On the viewer that will appear (http://www.ibge.gov.br/estadosat/). Using your mouse, hover over the various states until you find RO–Rondônia.

States in Brazil as shown on the IBGE data portal.

http://www.ibge.gov.br/home/

http://www.ibge.gov.br/english/

http://www.ibge.gov.br/estadosat/


Click Rondônia to access statistics for this state.

2.1) In what part of Brazil is Rondônia located? 2) Locate

Rondônia (contd.)

IBGE portal.

2.2) What is the 2010 estimated population for Rondônia?

Now that you know where this state is, you are ready to retrieve the data you need for the study.

3) Select Interactive Maps

Return to the main IBGE page, and under Channels, Database, select Mapas (Interactive Maps) as follows:


Click Rondônia to access statistics for this state. 4) Select Generalized Map

of Brazil

Choosing an interactive map.


The interactive map that appears after you select OK should look similar to the following:

4) Select Generalized Map of Brazil (contd.)

Generalized map of Brazil on the IBGE website.

Create a separate folder for each of the zip files, named biomes, general, agric_potential, soils, territories, and vegetation (or similar names that you will be able to keep organized). Note: You may have to enable your browser to allow pop-ups from this site.


Select and download the six categories of spatial data, one at a time. Download each dataset into its appropriate folder. For each of the six sets, you will need to first select the desired theme in the pull down menu in the upper right under Ver mapa.

5) Download data

Selecting the required datasets.


[1] Vegetation (Mapa de vegetacao). [2] Biomes (Mapa de biomas). [3] General Characteristics (Mapa de caracterizacao geral do Brasil)–make certain that you have checked (on the left side, in the list of map layers) all of the Transportes (transportation), the Outros (Other), the Imagem, and the Meio Fisico (Physical Environment) so that when you extract, you obtain all of the following layers:

5) Download data (contd.)

List of datasets to extract.

[4] Soils (Mapa de solos). [5] Potential Agriculture (Mapa de potencial Agricola). [6] Territorial Divisions (Mapa de Divisoes Territoriais). Select all of the 2005 layers, as shown next:



Selecting the 2005 layers for the Territorial Divisions.

For each layer required, select the extract (Extrair) button:



Extracting selected layers.

Select Extract (Extrair). After a short time, you will see a download screen, as shown next.

Downloading the Rondonia data.

Select Download and save your file to a folder on your computer.


6) Extract data Unzip each zip file into its appropriate folder.

Data category Shapefiles stored locally after downloading and unzipping

Biomes Bioma, uf

Vegetation Veg, agua, capital, uf

General bacia, hidro, ferrovia, rodovia, extremos, culminantes, porto,

usina, aerop_inter, capital, uf

Soils Solos, capital, uf

Agricultural Potential Potencial, agua, capital, uf

Territories 0, 1, 2, 3

6.1) Which shapefiles are duplicated among the different themes and folders?

End of work package

Work package 2: Analyzing your data Steps 7 - 12

7) Add data to ArcMap

Start ArcMap and a new empty map. Under the general folder, add all layers.

Set the coordinate system of the data frame to the WGS 1984 (under Data Frame Properties, Predefined, Geographic Coordinate Systems, World).

7.1) Do the datasets have a projection attached to them?

8) Set coordinate system

8.1) What are the advantages and disadvantages of this coordinate system for analysis? 8.2) What is the east-west distance in kilometers across Brazil at its widest point? 8.3) Can you determine the difference between the Culminantes and Extremos layers? 8.4) Can you determine the difference between the Ferrovia and Rodovia layers? 8.5) What is the relationship between the layers bacia and hidro?

Map the UF layer as unique values on the names of the states. 9) Name the states 9.1) What is the field that names each state?

Work package 2: Analyzing your data Steps 7 - 12

10) Add biome data

Under the biomes folder, add the layer bioma. Map the biome types as unique value.

Save your map document. The Amazonian rainforest isn’t the only biome under pressure from human use in Brazil. In fact, according to one source, 35 percent of the cerrado (savannah) biome (695,000 km2) has been converted to agriculture, cities, or grazing, compared to 13 percent of the area of the rainforest biome, and only 1 to 6 percent of the cerrado is under protected status. Chief land pressures are for soya, maize, rice, wheat, cattle, charcoal production for the steel industry, and urbanization.

10.1) What biome type occupies a tiny portion of east-southeastern Rondônia? What biome type occupies most of the rest of Rondônia?

11) Save

Under the territories folder, add the shapefiles 0, 1, 2, and 3. 12) Add shapefiles 12.1) Which of these four map layers contains polygons for the smallest geographic unit?

Examine map layer 0.shp’s attributes to answer the following.

12.2) Place the following names in the order of geographic area, from smallest to largest: mesoregiao, microregia, nome, and regiao.

End of work package

Work package 3: Analyzing data II - Clipping Steps 13 - 20

13) Add vegetation

From the vegetation folder, add the veg map layer, and make a unique value map on the field TIPO. The vegetation layer is the current vegetation cover of the area, rather than the natural vegetation as untouched by human impact. The densest forest (floresta ombrofila densa) once occupied up to half of Rondônia.

Select the state of Rondônia from the UF layer. Then, open the Systems Toolboxes and go to Analysis Tools > Extract > Clip in order to clip the veg layer to the UF layer with Rondônia selected, as shown next:

13.1) How much of floresta ombrofila densa would you say occupies Rondônia today?

Next, you will determine exactly how much of each type of vegetation exists within Rondônia.

14) Clip vegetation layer

to states layer

Clipping the vegetation layer to the extent of Rondônia.

14.1) Did you receive an error during the clip operation OR has the clipped shapefile, veg_clip, not been created?


15) Run Check Geometry

Sometimes, data downloaded from public domain portals contain errors. Here, a few of the polygons may have topology errors. To investigate the vegetation layer so that the clip will work, in the Systems Toolboxes, use Data Management > Features > Check Geometry on your veg layer. This operation will create a DBF file listing any errors encountered; the dbf file will be added automatically to your ArcMap document. (If not, add it manually.) Once the DBF file is added to your ArcMap, open the file and investigate the problem.

15.1) What is the problem with the veg layer?

To resolve the issue, use Data Management > Features > Repair Geometry on the veg layer to fix the problem. Re-run the clip tool to clip the veg layer to the state of Rondônia.

16) Run Repair Geometry

16.2) Briefly describe the spatial pattern of development in Rondônia.

16.1) Do you now have a veg_clip layer?

The Area Antropizada is the area most affected by human impact as it has been converted to agricultural use through the planting of crops or as pastureland.


17) Examine roadways layer

Turn on the roadways (rodovia) layer.

17.1) Name the roadway that is responsible for bringing the rainforest developers into the most impacted area of Rondônia.

Access your veg_clip layer’s attribute table. Select the Area Antropizada polygons. Right-click shape_area and select Statistics.

18) Generate statistics

19.1) How could you work with your data so that they would be in a more convenient and accurate unit? Don’t perform these steps, just indicate how you would go about changing the data to fix this unit problem.

Consider the map projection.

18.1) How much of the land in Rondônia is included in Area Antropizada? 18.2) Are these figures in square miles, square kilometers, or in some other units? If the area is reported in some other units, what units are they? 18.3) Are these units a convenient or accurate set of units to use for spatial analysis? Why or why not?

19) Projections

20) Save Save your map document.

End of work package

Work package 4: Analyzing data III - Summarizing and analyzing Steps 21 - 28

21) Quantify area of impact

To get a better assessment of the amount of land impacted in Rondônia, right-click the Shape_area field and select Summarize. Summarize on this field using TIPO First, as shown in the Summarize dialog box. Be sure to uncheck the box “Summarize on the selected rows only” because you want a summary of all of the rows (alternatively, clear any selected rows before running Summarize).

Summarizing the amount of affected land in Rondônia.


22) Select by vegetation type

Open your summary table. Select all of the Area Antropizada rows in the table using Select by Attributes, as shown in the Select by Attributes dialog box.

Selecting by vegetation type.

Notice that each polygon of Area Antropizada is listed separately. This makes it cumbersome to determine how much of Rondônia is covered by Area Antropizada.


23) Summarize by vegetation type

In your summary table, right-click shape_area > Statistics. You will see a histogram of data that summarize all of the Area Antropizada.

Generating vegetation cover statistics.

Label the capital layer on the field Nomemun.

23.1) What is the difference between the Statistics and Summarize functions? 23.2) What percentage of Rondônia (the Sum listed in the Selection Statistics of Sum_Output dialog box) is covered by Area Antropizada?

24) Identify capital 24.1) What is the capital of Rondônia, what river is it on, and what is the

vegetation type in the area of the city?


25) Assess municipalities

Turn on the 0.shp municipalities again and label. The Nome field that you examined earlier in 0.shp corresponds to the municipalities, but it is more like a city-state, with a city and its surrounding area.

Under the soils folder, add the layer solos (soils). You may need to turn it on or make vegetation semi-transparent (under the Effects toolbar or Display tab in Layer Properties) to answer the following question.

25.1) Which three municipalities around the capital would you say are under the most pressure of land development, and why? 25.2) Describe the directions that the rivers flow in Rondônia (hidro). 25.3) What rivers would you say would likely be most affected by increased sedimentation from development in this region?

26) Assess soil types

26.1) What soil type(s) (TIPO and DESC_) underlie most of the area under intense development in Rondônia? 26.2) Name at least two problems associated with developing land that is underlain by tropical soils for urban land use. 26.3) Name at least two problems associated with developing land that is underlain by tropical soils for agriculture.


27) Assess soil fertility

Under the potential agriculture folder, add the potencial map layer (potential for soils to support agricultural development). Map the potencial layer on the attribute FERTILIDAD (soil fertility).

27.1) What do you notice about the pattern of soil fertility (alta=high; media=medium; baixa=low; muito baixa=very low) related to the development in Rondônia? 27.2) Why do you think that soil fertility is related to land development? 27.3) Remembering the nome field that you examined earlier in 0.shp, which three municipalities would you say have the lowest fertility and yet have seen the most development? 27.4) How does the fertility of the soil encourage ongoing development of the rainforest into farmland and ranch land? 27.5) Do you consider the fertility ratings to be short-term or long-term ratings? Why?


End of work package

Work package 5: Analyzing satellite imagery Steps 29 - 38

29) Access satellite imagery

Next, you decide that you need a satellite image to see the fishbone pattern of roads branching off the main road into the rainforest. An excellent source for satellite imagery is the Global Land Cover Facility (GLCF). Access it at: http://glcf.umiacs.umd.edu/index.shtml

Global Land Cover Facility website.

29.1) What is the GLCF, and who operates it?

http://glcf.umiacs.umd.edu/index.shtml


30) Access Data and Products

Select the Data and Products link. On the next screen, select Landsat (under Satellite Imagery).

30.1) What is Landsat data? Who is responsible for operating Landsat and providing data from it? 30.2) What spectral bands does ETM+imagery occupy, and what is its spatial resolution?

31) Select Landsat data

Select the ESDI link (on the right hand side). Note: If this tool is not running when you need it, select the Download via FTP Server under Data Access instead and complete the following: Select directory WRS2. Select directory P231. Select directory r068. You should be at the following URL: ftp://ftp.glcf.umiacs.umd.edu/glcf/Landsat/WRS2/p231/r068/ Select directory p231r068_7x20010811.ETM-EarthSat-Orthorectified. Select file “p231r068_7t20010811_z20_nn70.tif.gz.” Save and unzip this file (28 MB zipped [gz format]).

ftp://ftp.glcf.umiacs.umd.edu/glcf/Landsat/WRS2/p231/r068/


31) Select Landsat data (contd.)

On the next screen, select: Map Search. On the left panel, select Landsat Imagery ETM+. This is the Enhanced Thematic Mapper imagery. Zoom in to southern Rondônia (or type in Rondonia in the Place tab).

32) Identify image path and row

Search for path and row WRS-2, Path 231, Row 068 as follows. The path refers to the Northeast-Southwest tracks that the Landsat takes in its orbit, and the rows refer to the segments along the orbit:

Identifying the correct Landsat imagery.


Select Preview and Download. You will see a list of images; select ID 035–088. Landsat sensors are sensitive to seven bands in the electromagnetic spectrum, from blue to mid-infrared. For this exercise, you will download only a file in one band, although for a more rigorous study, you would probably need to download all bands for multispectral analysis.

32) Identify image path and row

(contd.)

Land cover facility portal.

33) Access technical guide

Select Info to access the page http://glcf.umiacs.umd.edu/data/landsat/ and from there select Technical Guide (from list of options on right hand side).

Link to GLCF technical guide.

http://glcf.umiacs.umd.edu/data/landsat/


You should be looking at the following document at: http://glcf.umiacs.umd.edu/library/guide/techguide_landsat.pdf Notice that the document states that “Bands 4, 5, or 7 from ETM+ (Enhanced Thematic Mapper) are used to demonstrate vegetation conditions.

33) Access technical guide

(contd.)

35) Access metadata

Go back to your list of images and select download (make sure you still have file 035–088 selected). You will next see a list of files; select the metadata file (last one in the list), named with a .met extension. You will see from this list that the file you need that corresponds to Band 7 in the electromagnetic spectrum has the following name: BAND7_FILE_NAME = "p231r068_7t20010811_z20_nn70.tif

36) Download data

Exit your metadata file and download (save target as) and unzip the above nn70.tif file.

34) Access images

34.1) What band will you need for a Mid-Infrared 2.080 – 2.25 micrometer image?

Choose the band.

http://glcf.umiacs.umd.edu/library/guide/techguide_landsat.pdf


Add your Landsat image to your ArcMap session. Choose Yes to create pyramids to make your zoom and pan draw speeds faster.

37) Add imagery to ArcMap

Try symbolizing the data using a classified method and experiment with other symbolization and classification methods.


37.1) Using the Landsat image as your background image, make at least two observations about the pattern of development in this section of Rondônia.

Landsat image imported into ArcMap with roads and hydro vector data

End of work package

Work package 6: Synthesizing results Steps 39 - 40

Create a layout and paste it into this exercise document that includes your satellite image base, your vegetation, roads, and hydro data.

39) Communicate your results

Analyze the results of your investigation.

39.1) What other information do you think you will need to communicate the extent of the issues you have been examining in Rondônia?

40) Analyze results 40.1) What have you learned about development in Rondônia, Brazil, during

historic times up to the present day? 40.2) What area do you think will be targeted next for development? Why? 40.3) If you were going to study this region in a more rigorous way, what additional data—spatial or otherwise—might you need for this study? 40.4) Summarize in a few sentences what you have learned about using the GLCF as an image portal. What were its strengths and weaknesses portal? 40.5) Summarize in a few sentences what you have learned about using the IBGE. What were its strengths and weaknesses? 40.6) Is your use of IBGE or your use of GIS hampered if Portuguese is not your native language? 40.7) Do you think it is important for spatial data portals to be offered in more than one language? Who should fund such a translation effort? End of work package

1) What is a spatial data infrastructure? 2) Which component of a spatial data infrastructure is most important, and why? 3) Name three difficulties in setting up an international spatial data infrastructure. Which one do you think is the most challenging to its success, and why? 4) Name two advantages that the INSPIRE initiative will offer the spatial data community of users. 5) Name two concerns that have been voiced about the INSPIRE initiative and why they are of concern. 6) What is the difference between an international spatial data infrastructure and an international data portal? 7) Name three international data portals and indicate the advantages of each in terms of data themes, formats, and download options. 8) Compare and contrast the Helsinki Commission’s Baltic Marine Environment Protection Commission (HELCOM) and the Arctic Spatial Data Infrastructure (ASDI). 9) Which datasets did you examine from the Brazilian mapping, environment, and statistics agency in your study of Rondônia?

10)Name the types of satellite imagery hosted on the Global Land Cover Facility. Which type did you use?

Chapter 6 quiz

exercise six - analyzing land use and sustainability

Education