In Mongolia
We had observation in Mandalgob for 280km south of Ulanbator.
Fig.4.3 Observation in Mongolia
Fig.4.4 Measuring in Mongolia
5.Analysis
5.1.Estimate grass height
Figure 5.1 shows process flow for the estimate grass height. At first, it compensates distortion of images. Then height map is calculated by the parallax error using a based mapping method of stereo matching. In addition, it makes the vegetation cover image by the extract vegetation from compensated image using principal component analysis. The height map part of vegetation cover and the height map part of ground (it is the other vegetation cover) are made with height map and vegetation cover image. The ground height map has many holes by the part of vegetation cover. So, there are estimate from pixels around the hole. The height map of vegetation is made difference in height between vegetation and ground. Figure 5.2-5.8 show the images are made by each process.
Fig.5.1 Process Flow
5.2 Estimate Biomass
The equation of translation from volume to biomass is liner function as weight density (k) is constant.
Biomass=volume*k (5.1)
Figure 5.9 shows that the vegetation volume calculated from the height map of vegetation. Table 5.1 shows the compared result and true value.
Fig.5.9 Estimated Volume-Biomass
Table5.1 Result
| Cell No. |
Volume [cm3] |
Biomass [g] |
Estimated Biomass [g] |
Error [%] |
| JO01 |
7972 |
109.33 |
215.244 |
96.9 |
| JO02 |
2975 |
82.08 |
80.325 |
2.1 |
| JO03 |
5076 |
108.03 |
137.052 |
26.9 |
| JO04 |
2361.97 |
100.74 |
63.77319 |
36.7 |
| JO05 |
1515.7 |
78.54 |
40.9239 |
47.9 |
| B00 |
180.5 |
9.92 |
4.8735 |
50.9 |
| B01 |
253 |
10.08 |
6.831 |
32.2 |
| B02 |
207 |
11.86 |
5.589 |
52.9 |
| B03 |
341 |
10 |
9.207 |
7.9 |
| B04 |
420 |
8.58 |
11.34 |
32.2 |
