Lecture 13 - Estimating Earth surface properties from remotely sensed data

Question 1

What factors limit plant growth?

Answer 1

• Temperature and radiation over Eurasia
• Temperature and water
• Radiation and water in the Tropics

Question 2

Vegetation indices designed to monitor specific vegetation properties

Answer 2

Enhanced vegetation index - MODIS instrument
MERIS Terrestrial Chlorophyll Index (MTCI) - MERIS instrument

Question 3

What defines Leaf Area Index

Answer 3

LAI is defined as the one-sided green leaf area per unit ground area.

Question 4

What is EVI designed to do?

Answer 4

Estimate Leaf Area Index and canopy structure, thus providing info on vegetation amount

Question 5

What is MTCI designed to do?

Answer 5

Estimate chlorophyll content in vegetation canopy, thus providing info on vegetation condition.

Question 6

EVI advantages

Answer 6

1. Includes a blue band, allows accounting for residual atmospheric contamination
2. Minimise soil background effect
3. Sensitive to high biomass area

Question 7

Why do we need information on chlorophyll content?

Answer 7

Plays an important role of the productivity of plants
Indicator of: Biotic stress factors, abiotic stress factors

Question 8

Meris Terrestrial Chlorophyll Index (MTCI) wavebands

Answer 8

Contains 15 wavebands and includes four in “red edge” and thus sensitive to chlorophyll concentration.

Question 9

Advantages of using Vegetation indices

Answer 9

• Simplicity
• Many sensors have wavebands in red and NIR
• Relationships between LAI and VI can be extrapolated to larger areas.