Ciclonic path of Hurricane Pauline | Hydrological Basins | Altimetry | Climate | Isoterms | Isohyets | Edaphology | Land use and Vegetation | Forest Inventory | Priority Regions | Amphibians and Reptiles|

Birds | Plants | Mammals | Image taken on August | Image taken on November | Spectral Analysis | Multispectral Ratios  | Comparison of Images | Ground Survey
  Conabio » Monitoring of ecosystems » Natural desaster case Hurricane Pauline » Spectral Analysis
Para ver correctamente esta pagina su navegador debe soportar CSS
 
 

COMPARISON OF AUGUST-NOVEMBER IMAGES, IN RGB AND PRINCIPAL COMPONENTS

Shown are the August image (sections a, c) two months before the occurrence of Hurricane Pauline- and the November image (b, d) after the hurricane had hit the zone.

The image area is located in the eastern part of the affected zone, between Copalita and Río Grande rivers.

Images a and b are a color composite in RGB (Red, Green, Blue) of bands 5 4 and 3, while images c and d demonstrate principal component analysis. The result of the analysis illustrates the changes in different areas within the zone.

  1. The main modifications that can be observed in the scenes are caused by massive erosion due to high runoff after and during the rainfalls associated with the Hurrican. They are shown in blue colors. These are zones which define soil without or with low vegetation cover, mainly along riverbeds;

  2. In elevated areas of the basins degraded areas can be determined due to the removal of material which was afterwards deposited in the lower sections of the basins. (see Copalita and Río Grande rivers). Erosive processes are linked to the slope degree characterizing each basin. Therefore, zones with greater slopes (inclination) are generally the ones located in the upper parts of the basins, while in lower parts slope diminishes, thus leading to sedimentation of the carried material.

  3. Erosion induced the destruction of the vegetation, which can be identified in light green colors or light blue colors.

Note: Press the mouse button on any of the four images for a better resolution.

Oppress to see the image with more resolution

For doubts, questions or comments
Geographical Information Systems Sub-director