Table 3 Results of Grass GIS r.cross module between CVA map and MAF map (first component thresholded and classified for negative and positive values) in terms of pixels count and percentage over the study area for both case studies
From: A combined change detection procedure to study desertification using opensource tools
Oasis | Lake | |||||
|---|---|---|---|---|---|---|
r.cross categories | CVA classes | MAF1 values | Pixels count | % | Pixels count | % |
1 | No data | Negative | 990 | 0.31 | 1043 | 0.19 |
2 | Positive | 857 | 0.27 | 200 | 0.04 | |
3 | 1st quadrant (Moisture reduction) | No data | 685 | 0.21 | 143 | 0.03 |
4 | Negative | 39 | 0.01 | 182 | 0.03 | |
5 | Positive | … | … | 1 | 0.00 | |
6 | 2nd quadrant (Chlorophyll increase) | No data | 5551 | 1.73 | 2808 | 0.52 |
7 | Negative | … | … | … | … | |
8 | Positive | 8427 | 2.63 | 7406 | 1.37 | |
9 | 3rd quadrant (Higher moisture land and water bodies) | No data | 1420 | 0.44 | 17215 | 3.19 |
10 | Negative | … | … | … | … | |
11 | Positive | 390 | 0.12 | 9882 | 1.83 | |
12 | 4th quadrant (Bare soil and bare sand expansion) | No data | 16172 | 5.05 | 3645 | 0.68 |
13 | Negative | 6015 | 1.88 | 22480 | 4.16 | |
14 | Positive | … | … | … | … | |
15 | No data | No data | 279454 | 87.33 | 474995 | 87.96 |
Total | 320000 | 100 | 540000 | 100 | ||