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Coastal change Danube Delta change detectionOil spillsDeforestation Bardia National ParkCongo River BasinKameng-Sonitpur Elephant ReserveKilimanjaroRondoniaShillong and GuwahatiIce Antarctica 2003Climate change and glaciersGlacier analysis using radar imageryGlacial retreat in the AlpsGlacier Ice FlowMonitoring of glaciers in the HimalayasRemote sensing of ice and snowUrbanisation CairoCity of KathmanduCórdobaHimalayasKathmandu ValleyLagosVegetation Annapurna Conservation AreaLost in the AndesNgorongoro Conservation AreaNiger Inland DeltaVegetation in South America
| | | | | | | Analysis of Satellite Images - Part 2
This exercise is divided into four parts and requires the use of LEOWorks.
Repeat the previous steps, this time with the images from the year 2003. You should open all six LandsatETM_2003 images. Examine each of them and try out different colour combinations. Name the false colour combination 'FCC_2003_b432'.
Examine the differences between the two images, namely 'FCC_1994_b432' and 'FCC_2003_b432'.
1. Write short notes about the obvious changes. Are there any changes in the forest cover?
Forest areas converted to rice fields
Wires installed in rice fields
Forests are elephants' natural habitat. To find out more information about the forest cover, the Normalized Difference Vegetation Index (NDVI) shows the amount of vegetation cover in remote sensing images. Vegetation gives a strong reflection in infrared bands, whereas it gives a weak reflection in the visible bands. Why does this happen? This is because pigments in the leaf cells absorb most of the red and reflect most of the near infrared radiation from the source of energy, which is the Sun.
The calculation for NDVI is:
(band 4 – band 3) / (band 4 + band 3)
Open the LEOWorks programme. Choose File>Open, and then open LandsatTM_1994_b3.tif and LandsatTM_1994_b4.tif.
To calculate the NDVI, go to Tools/Compute NDVI, select LandsatTM_1994_b4 for the Infrared Band, and LandsatTM_1994_b3 for Red Band, and click OK.
Computing NDVI with selection of bands
Save the image as a tiff file and name it 'NDVI_1994'.
Compute the NDVI for 2003. Select LandsatETM_2003_b4 for Infrared Band, and LandsatETM_2003_b3 for Red Band.
Save the image as a tiff file and name it as NDVI_2003.
The green areas indicate a high chlorophyll density, which in turn indicates healthy vegetation.
Compare the NDVI image with the true- and false-colour images.
2. Are there any changes in forest cover?
If yes, in which part of the image can you spot the changes?
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| | Kameng-Sonitpur Elephant Reserve IntroductionElephant ReserveAsian elephantMan vs elephantExercises Worksheet introductionPaper map creation and study of Kameng-Sonitpur Elephant ReserveAnalysis of satellite imagesEduspace - Software LEOWorks 3ArcExplorerEduspace - Download ks_papermap.zipks_satelliteimg.zipResources Useful links
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