삼림의 물 , 흙보전기능면에서 본 임지의 초지전용

강위평 한국임학회 1982 한국산림과학회지 Vol.58 No.1

森林의 물, 흙 保全機能의 觀點에서 林地의 草地(放牧地包含) 轉用의 영향을 從來 發表된 關係文獻을 綜合하여 考察한 要約은 다음과 같다. 1) 放牧地에 있어서 落葉 등 地被物을 乾重量으로 비교할 때 禁牧區에 비하여 重牧區는 1/3, 輕牧區는 1/2로 減少되었다. 2) 放牧區의 土壤硬度는 全般的으로 硬化되었으며, 浸透强度는 低下되었다. 특히 이 경향은 소의 休息地에서 현저하였다. 3) 草地의 年土壤浸蝕量은 0.10∼0.02㎜범위로서 林地와 같다. 4) 草地造成의 前提로서의 開墾地의 年土壤浸蝕量의 比率은 林地, 全面伐採地, 全面伐採와 拔根地에서 各各 1 : 10 : 78로 나타났다. 5) 林地의 草地轉用은 植生連續의 後退이며, 地力을 低下시킨다는 說이 있다. 6) 草地造成의 문제점은 草地造成自體보다 造成뒤의 不實管理로 인한 土地의 荒廢化에 있다.

鎭海地區에 있어서 山地崩壞와 地形의 關係

姜渭平 慶尙大學校 1980 論文集 Vol.19 No.1

1979年 8月 25日 颱風 Judy號의 영향으로 鎭海市는 日降雨量 465㎜의 集中豪雨가 쏟아졌으며 이로 因한 山地崩壞로 38名의 人命死亡을 비롯하여 家屋 農耕地에 莫大한 被害를 주었다. 筆者는 現地를 踏査하여 1/25,000 地形圖에 崩壞地를 Plot하여 地形解析한 結果 다음과 같은 結果를 얻었다. 1. 山地崩壞個數는 71個, 面積合計는 15.3ha였으며 崩壞地의 크기는 0.1∼1.7ha의 범위였다. 2. 崩壞地의 傾斜頻度 分布는 正規分布를 하였으며 傾斜 31도에서 全體崩壞個數의 44%를 차지하였다. 3. 崩壞個數와 方位에 있어서는 南方位에서는 67%였지만 東과 西方間에 있어서는 거의 差가 없었다. 4. 標高에 關해서 崩壞個數는 標高 50m 內外에서28%가 發生하였으나 兩者間에는 一定한 경향이 거의 없다. On Aug. 25. 1979, a heavy rainfall of 460mm poured into Jinhae area by the influence of typhoon Judy. About 15.3 hectars of landslides from 71 different places by the downpour destroyed many houses, a lot of cultivated areas, reads and human lives etc. This study was carried out to investigate the relationships between the causes of landslides and topographycal factors such as altitudes, slop and bearings. For the purpose, the landslides was plotted on topographycal map (scale; 1/25,000) through the several on-the-spot-surveys. The results obtained by a topographycal analysis on the map could be summarized as follows; 1. The total area of the landslides from 71 different places was estimoted to 15.3 hectars, and the sizes of the landslides showed normal distribution and about 44 per cent of total land-slides occurred in the 31 gradient. 2. The inclination angles of the h\landslides showed normal distribution and about 44 per cent of total land-slides occurred in the 31 gradient. 3. About 67 per cent of the total landslides appeared on the south slop, but there were no distinct relationships between landslides and east or west slops. 4. As to altitudes, 28 per cent of the total landslides occurred on alltitudes 50m, but there was no distinct tendency between altitudes and landslides.

수량화(數量化)(II)에 의한 산사태사면(山沙汰斜面)의 위험도(危險度) 판별(判別)

강위평,무라이 히로시,오무라 히로시,마호섭,Kang, Wee Pyeong,Murai, Hiroshi,Omura, Hiroshi,Ma, Ho Seop 한국산림과학회 1986 한국산림과학회지 Vol.75 No.1

In order to get the fundamental information that could be useful to judge the potentiality of occurrence of rapid shallow landslide in the objective slope, factors selected on Jinhae regions in Korea, where many landslides were caused by heavy rainfall of daily 465 mm and hourly 52mm in August 1979, was carried out through the multiple statistics of quantification method (II) by the electronic computer. The net system with $2{\times}2cm$ unit mesh was overlayed with the contour map of scale 1:5000. 74 meshes of landslides and 119 meshes of non-landslide were sampled out to survey the state of vegetative cover and geomorphological conditions, those were divided into 6 items arid 27 categories. As a result, main factors that would lead to landslide were shown in order of vegetation, slope type, slope position, slope, aspect and numbers of stream. Particularly, coniferous forest of 10 years old, concave slope and foot of mountain were main factors making slope instability. On the contrary, coniferous forest of 20-30 years old, deciduous forest, convex slope and summit contributed to the stable against Landslide. The boundary value between two groups of existence and none of landslides was -0.123, and its prediction was 72%. It was well predicted to divide into two groups of them. 산사태안전도판별(山沙汰安全度判別)에 대한 기초자료를 얻기 위하여 1979년(年) 8월(月) 집중호우(集中豪雨)(일강우량(日降雨量) 465mm)에 의하여 산사태(山沙汰)가 발생한 진해지구(鎭海地區)를 모델로 하여 이 지구(地區)의 지형도상(地形圖上)($S=\frac{1}{5,000}$)에 $2cm{\times}2cm$(실면적(實面積) $100m{\times}100m=1ha$) 단위의 격자(格子)를 얹어 산사태지(山沙汰地) 74개, 비산사태지(非山沙汰地) 119개 계(計) 193개의 mesh에 대하여 산사태발생(山沙汰發生)의 각(各) 요인(要因) 및 수준(水準)을 계측(計測)하여 수량화(數量化)(II)의 수법(手法)에 의하여 해석(解析)한 결과 산사태발생(山沙汰發生)에 기여도(寄與度)가 높은 요인(要因)의 순위(順位)는 다음과 같다. 1) 식생(植生), 2) 종단사면형(縱斷斜面形), 3) 사면위치(斜面位置), 4) 경사(傾斜), 5) 방위(方位), 6) 곡수(谷數). 또 침엽수(針葉樹) 10년생(年生) 내외, 복합사면(複合斜面), 하강사면(下降斜面), 산록(山麓), 경사(傾斜), $10^{\circ}-15^{\circ}$, 방위(方位) NW, 곡수(谷數) 1개의 각(各) 수준(水準)이 불안전측(不安全側)에, 침엽수(針葉樹) 20~30년생(年生), 활엽수(?葉樹), 상승사면(上昇斜面), 평형사면(平衡斜面), 산정(山頂) 등의 수준(水準)이 안전측(安全側)에 기여(寄與)하고 있다. 그리고 판별구분치(判別區分値)는 -0.123이고 적중률(適中率)은 72%로서 비교적 양호한 양(兩) group구분(區分)을 할 수 있었다.

禿裸地形成과 그 誘發因子에 關한 硏究

姜渭平 慶尙大學校 1975 論文集 Vol.14 No.-

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.

임업토목측면에서 본 성력화 - 사방사업을 (砂防事業) 중심으로 -

강위평 한국산림과학회 1981 한국산림과학회지 Vol.54 No.1

수량화 (Ⅱ) 에 의한 산사태사면의 위험도 판별

강위평,촌정굉 (村井宏),대촌관 (大村寬),마호섭 ( Wee Pyeong Kang,Hiroshi Murai,Hiroshi Omura,Ho Seop Ma ) 한국산림과학회 1986 한국산림과학회지 Vol.75 No.1

In order to get the fundamental information that could be useful to judge the potentiality of occurrence of rapid shallow landslide in the objective slope, factors selected on Jinhae regions in Korea, where many landslides were caused by heavy rainfall of daily 465 ㎜ and hourly 52㎜ in August 1979, was carried out through the multiple statistics of quantification method (II) by the electronic computer. The net system with 2 × 2 ㎝ unit mesh was overlayed with the contour map of scale 1 : 5000. 74 meshes of landslides and 119 meshes of non-landslide were sampled out to survey the state of vegetative cover and geomorphological conditions, those were divided into 6 items arid 27 categories. As a result, main factors that would lead to landslide were shown in order of vegetation, slope type, slope position, slope, aspect and numbers of stream. Particularly, coniferous forest of l0 years old, concave slope and foot of mountain were main factors making slope instability. On the contrary, coniferous forest of 20-30 years old, deciduous forest, convex slope and summit contributed to the stable against Landslide. The boundary value between two groups of existence and none of landslides was -0.123, and its prediction was 72%. It was well predicted to divide into two groups of them.

85년 7월 부산 문현동 산사태재해에 관한 연구

강위평,우보명 ( Wee Pyeong Kang,Bo Myeong Woo ) 한국산림과학회 1985 한국산림과학회지 Vol.70 No.1

By the continuous and heavy rainfall of 615 ㎜ during 15 days, landslide disaster occurred on July 5, 1985 at a steep-sloped land in Munhyon-dong, Pusan. This landslide was sized about 50 m long at slided part and 50 m long at buried part down, 30 m in average width, and 2 m in average depth respectively. 37 human lives and the great amount of properties have been last as the result of this landslide from the steep-sloped land. Summarizing the results of this study, the national-wide plan for the steep sloped land failure control measures on the steep-sloped possible-danger places should be established in Korea.

87년 태풍 5호에 의한 경남지구의 산사태에 관한 연구

강위평,마호섭,정모근 ( Wee Pyeong Kang,Ho Seop Ma,Mo Geun Jeong ) 한국산림과학회 1988 한국산림과학회지 Vol.77 No.3

Many landslides occurred at the western part of Gyeongnam province by the typhoon No. 875. Their conditions and causes were investigated and were summarized as follows : The total number of landslide occurred was 2,490 and its area was 156.53㏊. In about 94% of landslides and about 97% of landslides area occurred in 3 counties, Sancheong, Hamyang and Geochang. The landslides smaller than 0.01㏊ was 49% of the total indicating that about half of them were the small landslides. Considering homogenous topography amount of precipitation and forest type landslides appeared to be mainly has a high affected by the geological factor because the landslides mainly occurred in the deep weathered soil of igneous rock. The landslides occured on concave slopes of 31 to 35° in steepness with low crown density. In the area of the deep weathered soil, landslide likely occur repeatedly. Therefore, regular erosion control works are recommended in the area of pos for disaster prevention and counter-measures.

1979년 8월 집중호우에 의한 진해지구의 산사태에 관한 연구

강위평 ( Wee Pyung Kang ) 한국산림과학회 1981 한국산림과학회지 Vol.52 No.1

On August 25, 1979 a heavy daily rainfall of 465 ㎜ pured into Jinhae area by the influence of Typhoon Judy. In consequence of the typhoon, 38 persons were killed, houses and arable land were demolished and caused wide ranges of landslides in the area. According to the previous investigation, there had been five cases of such typhoons accompanied a daily precipitation over 300 ㎜ for 27 years, however, there had not occurred any landslides before, even though it is reported that any typhoon accompanied by heavy daily rainfalls over 300 ㎜ is normally known to cause various kinds of landslides. This phonomenon was described to the fact that there has been a qualitative change in the agents of landslides such as precipitation, geology, topography and forest. Thus, in this report, the relations of the agents to the development of landslides were to be analysed and brought forth the following confirmation: 1. In the district, 71 landslides of which area covered 15.3 ha were observed. 2. In terms of geology of the landslided sites. 89 and 11% in numbers were observed in the andesite and the granite respectively, and the areas of those landslide estimated 45 and 55% respectively. 3. In a topographical point of view, 44% of the numbers of landslides (55% in area basis) were occurred within the slopes of 26-35°, while no landslides were observed in either lower (below 9°) or upper (above 41°) slopes. In terms of slope patterns, 39 and 33%, in numbers (52 and 46% on the basis of area) were observed in concave slopes and compound slopes respectively. 4. In terms of forest ages, the most landslides were observed in 5-15 year-old forest, of which averages were 2.19 landslides per 100 ha and 0.47 ha per 100 ha. However, no landslides were observed in the forest of over 26 years old. 5. Among the agents, precipitation, geology, topography are considered not to be controlled but the only agent, the forest, to be controlled by human beings. Thus, this firstly observed landslides at Jinhae District are conclusively considered as the result of qualitative changes of one agent, the forest, in the area.

산복사방공사시공지에 (山腹砂防工事施工地) 있어서 지형과 식생회복 (植生回復)

강위평 ( Wi Pyung Kang ) 한국산림과학회 1984 한국산림과학회지 Vol.64 No.1

This study was carried out to obtain the advanced basic data for hillside erosion control works. Recovery of vegetation in the hillside erosion control districts depends on various factors i.e., topographies, soil qualities, rain conditions and erosion control methods. The only relations between topographies and vegetation coverage were surveyed, since the other factors were equal in all those surveyed areas. The results obtained are summarized as follows; 1) Mean coverage values were decreased in order of 80%, 78.7%, 64.0% and 56.5%r in concave slope, uniform slope, compound slope and convex slope respectively. The mean coverage of all aspects was 69.8%. The slope pattern have a influence on formation of coverage. 2) Moisture ratio in soil and mean slope have an effect on the mean coverage value. 3) In the beginning of the hillside erosion control working, coverage (14.8%) by arbor species was too low comparing with that by herb. 4) It is more desirable to recover regetation by artificial planting or seed planting than by the natural vegetation in the barren hillside. In the beginning of the hillside erosion control working, it is difficult to expect vegetation recovery by natural species.