FOREST LAND ASSESSMENT OF KHON KAEN AND MAHASARAKAM PROVINCES

Abstract

A study of forest land assessment of Khon Kaen and Mahasarakam provinces is made utilizing black and white LANDSAT MSS band 5 and 7, 1 : 250,000 scale taken in 1979.

Khon Kaen and Mahasarakam provinces are classified into the urban and built-up land, two types of agricultural lands, namely, paddy field, and field crops mixed with trees or farm forest, four types of forest lands; dry evergreen forest, mixed deciduous forest, dry dipterocarp forest, and swidden areas, two types of water resources; reservoir or man-made water resources and natural lakes and ponds.

Evidence from the forest inventory revealed that in Khon Kaen forested area of 256,364 ha.having, the total saw timber merchantable volume of dry evergreen forest is 1,303,136 m³ (67.52 m³/ha) and the total dry weight biomass of 1,331,711.58 tons (69 tons/ha). The total fuel wood that can be exploited from this forest type is 386,386 m³ (20.02 m³/ha). Mixed deciduous forest has the total merchantable volume of saw timber about 1,390,548 m³ (34.17 m³/ha), and the total dry weight biomass of 2,005,398.32 tons (49.28 tons/ha). The total fuel wood is 3,634.877 m³ (in this forest type. Dry dipterocarp forest has the total merchantable volume of daw timber 164,986 m³ (5.62 m³/ha), whereas the total dry weight biomass is 661,800.72 tons (22.54 tons/ha), The total fuel wood can be harvested from this type of forest is 1,223,606 m³ (41.68 m³ /ha).

In the farm forest the average merchantable volume is about 17.55 m³/ha, whereas the average fuel wood of 18.86 m³/ha, and the average dry weight biomass of 14.47 tons/ha.

The comparison of land use between 1973 and 1979 of Khon Kaen province indicated that a total of 377,307 ha or 35.49 percent of the total forest land was disappeared during the past 6 years. The depletion rate is 16.28 percent per annum. This forest land was transformed into agricultural land of 371,503 ha (34.95 %). The increasing rate of the agricultural land is 10.40 percent per annum, whereas 600 ha of forest land was transformed into urban and built-up land (3.09%), and 5,204 ha transformed into water resources (2.79%).

The gross change of forest land use of Mahasarakam province between 1973 and 1979 is 111,404 ha or 19.26 percent. The depletion rate is 11.19 percent per annum. The forest land of this province are transformed into urban and built-up land of 300 ha (2.99% per annum), 110,524 ha into agricultural lands (4.61% per annum), and 580 ha into water resources (3.19% per annum).

Findings show that the total agricultural lands of Khon Kaen province is 769,833 ha (72.42% of the total area), out of this 661,728 ha (62.25%) are classified as legal occupation, and 108,105 ha (10.17%) are illegal encroachment. Mahasarakam agricultural land covers the area of 448,128 ha (77.48% of the total area); 426,389 ha (73.72%) of this areas are as legal occupation while the rest of 21,739 ha (3.76%) are of illegal encroachment.

According to the land use classification and field observation, the total of 381,556 ha (45.76%) of upland forests having potential for rangeland development and livestock raising.

In regard to soil chemical properties, the agricultural lands of the two provinces are poor in organic matter, nitrogen, phosphorus, potassium, and magnesium contents which substitute the major element of soil chemical properties as compared to the forest lands through soil reaction (pH) suggests the comparatively strong acidity.

A study of small scale reservoir potential was conducted over Khon Kaen and Mahasarakam provinces. Characteristics of the catchment areas and hydrological data were determined. Evident from the study shows that the recommended small scale reservoir potential sites of Khon Kaen province are K1 and K6 of Amphoe Nam Pong for shallow well, K2, K5 and K8 for village tank, and K7 for deep well; whereas at Mahasarakam province the recommended small scale reservoir potential sites are M3 and M6 for village tank, M1, M5 and M7 for deep well.