1. landsat vs. rapideye tree box s7 e39 (in dash line) 1 3 4 2 5 landsat 17/05/2010 rapideye...

1. Landsat vs. Rapideye TREE box S7 E39 (in dash line)

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Landsat 17/05/2010 Rapideye 02/07/2010

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Site2

Site3

Site 4

Site5

2. Change detection

Landsat 17/5/2010

Rapideye 2/7/2010

Landsat 30/6/2000

Landsat 30/6/2000 Landsat 1/7/2010 Rapideye 2/7/2010

3. Forest cover detectionLandsat 1/7/2010

Rapideye 2/7/2010

VHR image 05/10/2009

Object-based segmentation

Rapideye vs. Landsat

Landsat 2010

Rapideye 2010

Analysis of no-change polygons

Landsat overestimation of logged area

VHR

LS

RE

VHR

LS

RE

Non detection of small forest blocks

82% forest cover

81% forest cover

47% forest cover

VHR

LS

RE

Underestimation of forest cover

y = 0.6111x - 0.1532R² = 0.3624

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forest proportion - high resolution

Landsat Polygons greater than 0.5 ha

Rapideye vs. Landsat

• In fragmented landscapes, Landsat fails to detect forest in many areas with forest cover of 20-90% (errors of omission)

• In homogeneous landscapes, Landsat fails to detect small canopy openings (errors of forest commission)

• Landsat forest estimates have high variance in those areas with forest cover higher than 90% (inaccuracy and lack of precision).

y = 0.8023x - 0.0648R² = 0.6169

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forest proportion - high resolution

'Sentinel' Polygons greater than 0.5 ha

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forest proportion

Area and detection - Landsat

Rapideye vs. Landsat

• Landsat fails to detect forest in many areas smaller than 1 ha.

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gon

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forest proportion

Area and detection 'Sentinel'

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forest proportion

Area and detection - High resolution

Actual distribution of forest cover within polygons from VHR data (just for comparison with the previous slide).

Landsat overestimation of logged area

VHR

LS

SE_S

VHR

LS

SE_S

Non detection of small forest blocks

82 % forest cover

76 % forest cover

47 % forest cover

VHR

LS

SE_S

Underestimation of forest cover