Invasive Species Mapping in Hawaiian Rainforests Using Multi-Temporal Hyperion Spaceborne Imaging Spectroscopy

Transcription

1 Application Invasive Species Mapping in Hawaiian Rainforests Using Multi-Temporal Hyperion Spaceborne Imaging Spectroscopy Ben Somers Gregory P Asner

2 invasive species threat?

3 invasive species threat? Molnar et al., Frontiers in Ecology & the Environment, 2008

4 invasive species monitoring?

5 invasive species monitoring? Field Scouting Remote Sensing

6 RS in mixed vegetation systems? spectral similarity & spectral mixture problem! white oak virginia pine Yellow poplar Van Aardt & Wynne, 2001, PEARS October 2010

7 study area Hawaiian Ecosystems at Risk project (HEAR) Invasive species information for Hawaii and the Pacific The mission of the Hawaiian Ecosystems at Risk project (HEAR) is to provide technology, methods, and information tools and to facilitate communication among decision-makers, resource managers, and the general public to help support effective science-based management of harmful non-native species in Hawaii and the Pacific. Hawaii Invasive Species Council > 9000 organisms have been introduced; 120 plant species are considered highly invasive The Hawaii Invasive Species Council (the Council or HISC) was established for the special purpose of providing policy level direction, coordination, and planning among state departments, federal agencies, and international and local initiatives for the control and eradication of harmful invasive species infestations throughout the State of Hawaii and for preventing the introduction of other invasive species that may be potentially harmful , VITO NV

8 study area Daniel Akaka US Senator for Hawaii Nearly $4.5 Million Stimulus Funds Will Fight Invasive Species in Hawaii Thu, May 14, 2009 WASHINGTON - Senate Appropriations Chairman Daniel K. Inouye and Senator Daniel K. Akaka announced today that the State of Hawaii will receive $4,486,000 to fight invasive plant species across the islands. The United States Department of Agriculture is distributing the funding as part of the American Recovery and Reinvestment Act. Specific projects on both state and private lands will be selected by the State government. "Many of our irreplaceable native forests and flora are in danger of being lost forever because of invasive species that have come to Hawaii from other parts of the world," said Chairman Inouye and Senator Akaka. "This funding will be a big help in our battle to save our unique Hawaiian plants that exist nowhere else, while creating job opportunities for workers across the islands. We will continue our efforts to get federal funding for this serious challenge." , VITO NV

9 study area Hawaii Volcanoes National Park Ohia (Metrosideros) Forest Kilauea Iki Crater Lava Flows Kilauea Caldera Hawaiian Archipelago October 2010

10 study area Ohia (Metrosideros) Forest Hawaii Volcanoes National Park Hawaiian Archipelago October 2010

11 study area Hawaii Volcanoes National Park Native Metrosideros (low leaf nitrogen and high canopy water) Morella infestations (high leaf nitrogen And low canopy water) October 2010

12 study area High spectral similarity Mixed nature of pixels multitemporal unmixing chain EO-1 Hyperion data October 2010

13 Objective? SPECTRAL MIXTURE MODELING SPECTRAL ENDMEMBER EXTRACTION MULTI-TEMPORAL SPECTRAL MIXTURE ANALYSIS Multi-temporal hyperspectral October 2010

14 Some remarks? Step-by-step implementation of multi-temporal spectral unmixing chain You will do some steps; I will do others (due to time constraints) Due to copyright issues I m not allowed to provide you with all data. We will work with a limited set of images and with modified spectral information and ground truth (concept is important!) We have done all our coding in Matlab and R for Statistics. We normally do not use ENVI (you re more of a ENVI specialist than I am!) We will perform a simplified approach to demonstrate the concept and potential benefits of multi-temporal unmixing October 2010

15 multi-temporal spectral data? Data Hyperion image for March, August & October 2004 (61 bands, spectrally resampled, NIR reflectance has been removed) 1. Temporal Unmixing map Images subfolder > March, August, October 2. Read & display images March August October

16 multi-temporal spectral data? Data Hyperion image for March, August & October 2004 (61 bands, NIR reflectance has been removed) 1. Temporal Unmixing map Images subfolder 2. Read & display images (z-profile)

17 multi-temporal spectral data? SPECTRAL MIXTURE MODELING SPECTRAL ENDMEMBER EXTRACTION MULTI-TEMPORAL SPECTRAL MIXTURE ANALYSIS

18 multi-temporal spectral data? Endmembers? Native Invasive Invasive Subfolder Endmembers (two vector files)

19 multi-temporal spectral Unmixing? March August October SPECTRAL MAPPING METHODS LINEAR SPECTRAL UNMIXING

20 multi-temporal spectral Unmixing? March August October LINEAR SPECTRAL UNMIXING 1. Input Image 2. Mask band (read mask image, subfolder mask ) 3. Endmember collection?

21 multi-temporal spectral Unmixing? March August October LINEAR SPECTRAL UNMIXING 3. Endmember collection? 4. Import from EVF from input file 5. endmembers!!!! 6. Select All + Apply

22 multi-temporal spectral Unmixing? March August October LINEAR SPECTRAL UNMIXING Show invasive species map

23 multi-temporal spectral Unmixing? March August October LINEAR SPECTRAL UNMIXING 1. Tools 2. Color Mapping 3. Density Slices 4. Clear ranges 5. Options 6. Add new ranges (-100 to 0.5 cyan) 7. Apply

24 multi-temporal spectral Unmixing? March August October

25 multi-temporal spectral Unmixing? August March October

26 multi-temporal spectral Unmixing? NIR2 VIS SWIR1 March August October March Spectral Separability?!

27 multi-temporal spectral Unmixing? VIS BEST SEPARATION IN: OCTOBER Black = March Green = August Red = October

28 multi-temporal spectral Unmixing? NIR2 BEST SEPARATION IN: AUGUST Black = March Green = August Red = October

29 multi-temporal spectral Unmixing? SWIR1 BEST SEPARATION IN: MARCH Black = March Green = August Red = October

30 multi-temporal spectral Unmixing? March August October Best separability Temporal composite August October March

31 multi-temporal spectral Unmixing? March August October Best separability Temporal composite August VIS/SWIR October/March chlorosis in invasive when wet and cool NIR August invasives grow better LAI October March

32 multi-temporal spectral Multi-temporal hyperspectral? endmember variability temporal unmixing HYPOTHESIS: no change in cover fraction during the considered time frame!!!! (acceptable in many applications if time frame is adapted to specific boundary conditions) SPECTRAL MIXTURE ANALYSIS temporal image stack R satellite,1, t1 = R 1,t1,tree1 * F tree1 + R 1,t1,tree2 * F tree2 + E 1 R satellite,1,t2 = R 1,t2,tree1 * F tree1 + R 1,t2,tree2 * F tree2 + E 2 R satellite,2, t1 = R 2,t1, tree1 * F tree1 + R 2,t1, tree2 * F tree2 + E 3 R satellite,2, t2 = R 2,t2, tree1 * F tree1 + R 2,t2, tree2 * F tree2 + E 3

33 multi-temporal spectral Unmixing? TEMPORAL COMPOSITE Endmembers Image - March August October August October March

34 multi-temporal spectral Unmixing? TEMPORAL COMPOSITE Image stack? BASIC TOOLS LAYER STACKING Import file

35 multi-temporal spectral Unmixing? TEMPORAL COMPOSITE Image stack? BASIC TOOLS LAYER STACKING October band 1 to 20 August band 21 to 30 March band 31 to 61

36 March August October March (VIS) August (NIR) October (SWIR)

37 March (VIS) August (NIR) October (SWIR) March (all bands) August (all bands) October (all bands)

38 multi-temporal spectral Multi-temporal hyperspectral? iterative mixture analysis cycles MESMA, Roberts et al., RSE, 1998 spectral transformations Zhang et al., TGRS, 2004; Rivard et al., TGRS, 2008 temporal unmixing Lobell & Asner, RSE, 20004; Singh & Glenn, IJRS, 2009 endmember variability spectral feature selection data integration Asner & Lobell, RSE, 2000;Somers et al., IJRS, 2010 Somers et al., IJRS, 2010

39 multi-temporal spectral Unmixing?

40 multi-temporal Thank You! Questions? spectral SPECTRAL TIME SPACE