禿裸地形成과 그 誘發因子에 關한 硏究 = Studies on the formation of Forest bareland and its causes in Korea

다국어 초록 (Multilingual Abstract)

The forest barelands, a kind of destructive forest land, are distributed widely in Korea which cause not only the decrease of land productivity but also transport soil and sand to the lower reaches of a river.
With this reasons, the exist of forest barelands prohibit the development of other related industries. The continous and disorderly tree felling is mainly regarded as a causing effect, however those factors, i.e, topography, geology, plant vegetation could give great influences to the formation of bareland.
The former is regarded as the inducible characteristics such as human activity and the later as inherent characteristics originally involved in situ.
With the aim to disclose the causes of forest bareland formation, which prevents the industrialization of a country, and to contribute finding the methods of prevention, and rehabilitation techniques, the relations between the inherent characteristics, such as topoghaphy, geology and climatic factors and bareland formation are analyzed.
In this study, the aerial photograph of Korea supplied by courtesy of the Forest Resources Research Institute, The forestland use classification map of th scale of one~fifty thousandth, the geological map of Korea, meteorological date recorded for 30 years period, are used.
Those factors, not natural but artificial, have not been cousidered in this analysis. The results obtained are concluded as follows.
1. The total area of forest bareland in Korea is accounted 63,545 hectars, in number basis, 2,985 locations. Gyeong-bug prevince occupies 45 percent of total bareland area, as the maximum.
The ratio of bareland to the forest land area by provinces, Gyeong-gi and Gyeong-bug rank the highert, 1.9 percent and Gang-weon and Chung-hug as the lowest, 0.1∼0.2 percent respectively. The average percentage of bareland is 0.9.
2. 70 percent of total bareland area are distributed over altitude class 200m, which are characteristically rolling hill condition, as maximum with relation to altitude effect, and no bareland has been found beyond the 850 m above sealevel.
But contrary to this, landslide occured more between 1, 200 m and 1, 300m above sea level, mostly alpine rezion.
With regarding the relation of slope to bareland formation, 72 percent of total bareland area has not occupied between 12 and 19 degree in slope, which is considered as gentle slope, hut that has not been found at the places steeper than 31 degree. However, landslide phenomena have usually been found over the places between 31 and 40 degree of slope, on sleeper area.
4. With regarding the relation of aspects and bareland formation, 38 percent of total bareland area has been recorded on the southern aspect, as the maximum. No significant differenes could be found among other three aspects. No relation is existed between aspects and landslide development.
5. In relation to between the shapeness of slope and bareland formation, 61.8. percent of the total bareland area on the convex slope, 26.9 percent on the uniform slope, 8.3 percent on the compound slope, and 3 percent on the concave slope are recored.
On the contrary, The appasite orders have been obtained between slope shapeness and landslide formation.
6. In relation with geology, 57 percent of the total bareland area are distribuled over granite zone as the maximum, 20 percent on Gyeong-sang system as the next, and 17 percent on granite and gneiss zone as the third.
And other geological conditions have abruptly weak relation to bareland formation
7. In relation between the ratio of bareland distribution and respective geological conditions, of the total Korean peninsula basis, granite, Gyeong-sang system and tertiary have contributed about 0.72 percent of the bareland area respectively This is the synonymous simply to the facts explained under head 6.
The landslide phenomena are also linked closely with the geological conditions, namely, the of more formation on granite and granite-gneiss
8. The bare land is liable to form on those districts where have about 200 mm of rainfall during March, April and May, three months spring period, accounted as dry region.
This dryness is considered to relate with the growth depression of pinus densiflora vegetation, plant community symboliges the comeing devestation of forest land.