GE 220 Quiz - Unit06: Vegetation Indices

1. How is NDVI calculated?

The following NDVI values are obtained for the following sites: 

Site 1 = -0.08,
Site 2 = 0.85 and
Site 3 = 0.06.
Assess, using the NDVI values, what type of land class each of these sites belong to.

• Site 1: Vegetated areas, Site 2: Clouds, water, and snow, Site 3: Rock and bare soil areas

• Site 1: Rock and bare soil areas, Site 2: Clouds, water, and snow, Site 3: Vegetated areas

• Site 1: Clouds, water, and snow, Site 2: Vegetated areas, Site 3: Rock and bare soil areas

Based on answer to question 2 above, qualify why the three sites belong to those land classes.

Where the sites are Site 1 = -0.08, Site 2 = 0.85 and Site 3 = 0.06

And the classes are Vegetated areas, Rock and bare soil areas and Clouds, water and snow areas.

Given the following digital numbers from two different bands, calculate the Simple Ratio values for each pair.

Band A DNs: 62, 49, 19, 27 and

Band B DNs: 71, 63, 24, 31

Based on answer to question 4 above, what can you conclude about the features represented by the Simple Ratio values?

Band A DNs: 62, 49, 19, 27 and

Band B DNs: 71, 63, 24, 31

What are the typical NDVI values for the following ground features: (i) bare soils, (ii) dessert vegetation, (iii) tropical forest and (iv) water.

List 5 application areas of NDVI.

Why is Leaf Area Index an important biological parameter? Give two reasons.