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Land cover change and pasture estimation of Mongolia from space
Land cover map of Mongolia
- The Classification schema
Considering the resolution of the AVHRR data and seasonal spectral curve of all classes, minimum mapping unit and expert's views in the field, the following 11 land cover types were identified for Mongolia. The methodology of producing the land cover maps for 1992/1993 and 1997 is almost the same.
Land cover types of Mongolia in 1992/1993 and 1997 are given in the Table 1. The Land cover map is in UTM project (zone utm-48n). Both classification results are converted to IGBP classification scheme.
- Land Cover Distribution and Assessment
From the interpretation of multi-date NOAA/AVHRR data of 1992/1993 and 1997 found that the total forest area in Mongolia including deciduous needleleaf, deciduous broadleaf, coniferous forest and all mixed forest is about 12.7% (see Table 1). But there were some difficulties to distinguish saxaul forest in southern part of territory, which is included into official total amount of forest area.
Grassland consisting of permanent pastureland and a tall and a short mountain grasses with shrubs. In Mongolia the cropland has complex cropping patterns depending upon the topography, seasonal climate, vegetation condition.
However, in Southern part of Mongolia is gobi desert area and it has too sparsely vegetation.
Table 1. Land cover types of Mongolia
| 1992 | 1997 |
| Category |
Class Name |
Class Id |
Area (in Ha) |
Area (in Ha) |
| Water |
Water body |
1 |
1606834 |
1226685 |
| Barren |
Desert shrubland |
2 |
|
5226704 |
|
High mountain (rocks) |
3 |
15990 |
2742531 |
| |
Barren or sparse vegetated |
8 |
38379477 |
45308976 |
| Grassland |
Grassland |
4 |
67018933 |
15930215 |
| |
Steppe |
5 |
|
37902374 |
| |
Dry steppe |
6 |
21422068 |
24433793 |
| |
Cropland |
7 |
7601494 |
3264166 |
| Forest |
Needleleaf forest |
9 |
12893895 |
15402268 |
| |
Broadleaf forest |
10 |
859230 |
3185248 |
| |
Mixed forest |
11 |
6042591 |
1328226 |
| Total area |
|
|
155890514,0 |
155901185,3 |
- Analysis of 1992 and 1997 land cover maps
Before making comparison analysis we made some corrections to the land cover map of 1992. Previous version of 1992 land cover map forest was not clearly identified and in version of 1997, we made DEM analysis to distinguish grassland area and forest and finally we got more better classification of forest in central part (the Khangai mountain area) and north eastern part, where locates the Khentii mountain ridge. And also we made some changes in classification scheme and name of classes in order to compare both maps of 1992 and 1997.
Figure 1. Land cover map of Mongolia, 1992
Figure 2. Land cover map of Mongolia, 1997
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