저사저수구의 (貯砂貯水溝) 유토저지효과에 (流土沮止效果) 관한 연구

이수욱,이태수 ( Soo Wook Lee,Tae Soo Lee ) 한국산림과학회 1976 한국산림과학회지 Vol.31 No.1

This study was carried out to find out the effect of soil and water storable pits on reducing the surface runoff. 10 pits were digged in each plot of 50 ㎡ along contour line. One kind of pits has a size of 30 ㎝ width, 100㎝ length and 30㎝ depth, and the other has 30㎝ width, 100㎝ length and 20㎝ depth. 1. The soil and water storable pits have a significant effect on reducing surface runoff. Control plot had surface runoff 2.3-2.6 times more than the plots with pits. 2. There is no significant difference in surface runoff between 30㎝ depth pit and 20㎝ depth pit. 3. The soil and water storable pits did not have any effect on coverage, survival and growth of three species. 4. Steep slope had worse results than the other slopes in coverage, growth and fresh weight of experiment species.

황폐지 토양수분이 묘목의 (苗木) 생장 및 양분흡수에 미치는 영향

이수욱,김지문,송호경 ( Soo Wook Lee,Chi Moon Kim,Ho Kyeong Song ) 한국산림과학회 1978 한국산림과학회지 Vol.38 No.1

In afforestation of denuded forest land soil conditions playa very important role in early growth of cover vegetations. This study was designed for understanding the effect of soil moisture regime on growth and nutrient uptake of some seedlings. Cover vegetations such as Pinus rigida Miller, Robinia pseudoacacia L. and Lespedeza bicolor Turcz. were planted in pot with the soil transported from denuded forest land in Musu-ri Sannae-Myeon. Daedeog-Kun, Chungnam Province. There were 3 moisture treatments and 4 fertility levels in P₂O_5 with 4 replications. Influence on growth was observed by the variation in dry weight and nutrient uptake was studied in nitrogen, phosphate and kalium. Results are as follows: 1. For Pinus rigida seedlings decrease in soil moisture tension increases growth of dry weight and enhance the uptake of kalium. Increase in P₂O_5 fertility level tends to decrease the uptake of kalium rather than increase in P₂2O_5 uptake. 2. In Robinia pseudoacacia increase in soil moisture content stimulates the uptake of nitrogen and kalium. Increase in P₂O_5 level enhances the uptake of P₂O_5 and increases growth of dry weight. 3. In Lespedeza bicolor increase in soil moisture content has a tendency of decrease in nitrogen uptake. Increase in P₂O_5 level increases the growth of dry weight as well as the uptake of P₂O_5.

농과대학(農科大學) 부여(扶餘) 연습림(演習林)의 식생조사(植生調査)

이수욱,김지문,송호경,Lee, Soo-wook,Kim, Chi-moon,Song, Ho-kyung 충남대학교 농업과학연구소 1977 Korean Journal of Agricultural Science Vol.4 No.2

충남(忠南) 부여군(扶餘郡) 은산면(恩山面) 라령리(羅嶺里) 소재(所在) 본대학(本大學) 연습림(演習林)은 온대(溫帶) 중부(中部)의 참나무류(類)의 극성상(極盛相) 임분(林分)이 대부분(大部分) 파양(破壤)되어 남면(南面)과 산봉(山峰)을 연결(連結)하는 능선(稜線) 부분(部分)은 소나무 단순림(單純林)의 준극성상(準極盛相)을 이루고 있다. 식생(植生)은 비교적(比較的) 다양(多樣)하며 주요(主要) 수종(樹種)은 소나무, 상수리나무, 굴참나무, 갈참나무, 졸참나무, 비목나무 굴피나무등이며 목본 53과 203종, 초본 49과 128 종이다. 이들 식물(植物)을 이용도(利用度)에 따라 분류(分類)하면 다음과 같다. 식용(食用) 식물(植物) 60과 154종, 약용(藥用) 식물(植物) 63과(科) 143종(種) 초자원(草資源) 식물(植物) 51과 140종, 관상(觀賞) 식물(植物) 32과(科) 78종(種), 용재수종(用材樹種) 12과 27종등이다. The experimental forest of Cbungnam National University is located in Naryung-Ri, Eunsan-Myen, Buyeo-Gun, Chungcheongnamdo. The climax vegetations of Quercus species grown in centrual temperate zone are supposed to be destroyed before pure pine stands as a semi-climax vegetation are established on the southern aspect and along the ridges. Variability of vegetations is rather high and dominant species are such as Pinus densiflora, Quercus acutissima, Quercus variabilis, Quercus aliena, Quercus serrata, Lindera erythrocarpa, Platycarya strobilacea, and so on. There tare 203 woody plants and 128 herbal plants. According to the use of vegetations they can be classified as follows; 60 familia and 154 species for edible source, 63 familia and 143 species for medicinal, 51 familia and 140 species for forage, 32 familia and 78 species for ornamental, and 12 familia and 27 species for timber source.

산사태(山沙汰) 발생요인(發生要因)에 관한 연구(硏究) -평창군(平昌郡) 석회암지대(石灰岩地帶)를 중심(中心)으로-

이수욱,Lee, Soo-Wook 충남대학교 농업과학연구소 1979 Korean Journal of Agricultural Science Vol.6 No.2

평창군(平昌郡)에 발생(發生)한 산사태지(山沙汰地)의 유형(類型)은 다음과 같으며 그특징(特徵)을 보면, 1. 석회암(石灰岩) 심토지대(深土地帶) 토양단면상(土壤斷面上)에 점토(粘土)의 집적(集積)으로 토성(土性)의 차이(差異)가 뚜렷하여 수분(水分)에 의한 윤활작용(潤滑作用)으로 니류형산사태(泥流型山沙汰)가 발생(發生)한다. 2. 석회암(石灰岩) 암반지대(岩盤地帶) 표토(表土)의 두께가 얇고 평활(平滑)한 암반층(岩盤層)이 존재(存在)하므로 집중호우시(集中豪雨時) 표층토(表層土)가 쉽게 포화(飽和)되고 암반경계부(岩盤境界部)에 수분윤활작용(水分潤滑作用)으로 표토(表土)가 분리(分離) 붕락(崩落)한다. 3. 화강암지대(花崗岩地帶) 조립질토성(粗粒質土性)의 모재(母材)는 응집력(凝集力)이 적으며 공극(孔隙)이 많고 삼투능이 커서 수분(水分)에 의한 식화(蝕和) 및 분리작용(分離作用)이 신속하여 쉽게 기암층(基岩層)으로부터 붕락(崩落) 계안(溪岸)을 침식(浸蝕)한다. 본지역(本地域)의 산사태예방책(山沙汰豫防策)으로 다음을 들 수 있다. 1. 산사태근원지(山沙汰根源地)의 집중조림(集中造林) 및 사방공작물(砂防工作物) 설치(設置). 2. 급경사지(急傾斜地)($25^{\circ}$이상)의 개벌(皆伐) 및 개간경작(開墾耕作)의 억제(抑制) 3. 산사태방비림(山沙汰防備林) 조성(造成). The characteristics of landslides occurred in August 5, 1979 in pyeongchangkun were surveyed and indentified as follows. 1. Deep limestone regions. Distinct differences in soil texture between A1 and B horizon could be observed on soil profile, which is attributed to the clay illuviation. The clay illuvial horizon is supposed to be an important cause of large scale mudflows on middle slopes by the lubricant action of ground water flowing between top soil and subsoil. 2. Shallow limestone regions. Very shallow top soils (less than 50cm) laid on tilted bedrock stratification provide a proper condition of mass soil movement if the top soil is saturated and ground water flows between top soil and bedrock when concentrated heavy rainfalls shower. 3. Granite regions. Weathering granitic bedrock produces very coarse textured top soils which are very cohesionless and have many pores. Therefore, the soil has high infiltration ratio and is easy to be saturated by water and to be detached from the bedrock. The landslides abrase very severely both sides of gully with high potential energy when they flow down. The following methods for landslide prevention can be recommended. 1. The original parts of landslides on top of the gully must be treated by intensive planting of deep rooting species and check dams. 2. Clear-cutting and crop planting on steep slope (more than 25 degrees) should be controlled and prohibited. 3. Establishment of landslide prevention forest should be practised on proper site.

대기오염 및 산성우가 (酸性雨) 삼림생태계의 토양산도 (土壤酸度) 및 양료분포에 (養料分布) 미치는 영향

이수욱,민일식 ( Soo Wook Lee,Ill Sik Min ) 한국산림과학회 1989 한국산림과학회지 Vol.78 No.1

Four regions have been selected and surveyed to investigate the effects of air pollution and acid deposition on forest ecosystem. They were Seoul as urban region, Yeochon and Ulsan as industrialized region, and Kangwondo as uncontaminated region. Soil pH and the distribution of elements were analyzed in process of time for three years as well as by distance from pollution sources. In general, forest soils acidified in process of time from pollution sources to suburban areas. Hydrogen ion concentration in forest soils increased in 1988 as much as 60% of that in previous year. Average soil pH values in coniferous forest were 4.45 in Seoul, 4.54 in Yeochon, 4.81 in Ulsan, and 6.03 in Kangwondo. Forest soil pH increased with the distance from pollution sources to suburban areas at constant rate within short ranges (up to 30 ㎞) and at decreasing rate within long ranges (up to 200 ㎞). On the contrary, sulfur content in soils decreased every year except in Yeochon region. Base saturation of forest soils in polluted regions were all below 20% level compared with 70% in Kangwondo region. Active aluminum content in soils increased with the soil acidification at the highest rate in Yeochon, and the next in Ulsan and Seoul, Heavy metal content such as copper and zinc in tree tissues were the lowest in Kangwondo region, and the next in Yeochon, Seoul and Ulsan.

山沙汰 發生要因에 관한 研究

李壽煜(Soo-Wook Lee) 충남대학교 농업과학연구소 1979 農業技術硏究報告 Vol.6 No.2

강원도산 소나무천연림생태계의 Biomass 및 Net Primary Production 에 관한 연구

이수욱 ( Soo Wook Lee ) 한국산림과학회 1985 한국산림과학회지 Vol.71 No.1

Dimension analysis was used to estimate biomass and net primary production(NPP) in a 36-year-old Japanese red pine (Pines densiflora S. et Z.) natural forest in Kangwondo. Best estimation was made by the equation model of Wt=aD^bH^c where Wt is weight in ㎏, D is DBH in ㎝, and H is total tree height in m. Total aboveground biomass was estimated at 198.82 t/㏊. Organic matter was distributed in the Japanese red pine stand as follows ; bolewood 68.8%, live branches 16.5%, bolebark 5.4%, foliage 4.6%, dead branches 3.7%, and cones 0.6%. Net primary production was estimated at 15.87 t/㏊/yr and was distributed: bolewood 44.5%, live branches 30.9%, foliage 14.1%, current twig 7.1%, and bolebark 3.3%. Leaf efficiency was estimated at 1.876. The power equation for biomass and IVPP yielded similar results as the results for Pines densiflora in Japan.

토양수분이 피복용식물의 (被覆用植物) 생장 및 수분경제에 미치는 영향

이수욱 ( Soo Wook Lee ) 한국산림과학회 1977 한국산림과학회지 Vol.33 No.1

This study has been made to find out more effective way of vegetation establishment on severely denuded forest land from the viewpoint of soil moisture regimes. Various environmental factors were measured to estimate soil moisture conditions of different sites. Soil moisture influence on growth of over vegetations, water requirement and drought resistance were analyzed. The efficiency of water use was also reckoned at different fertility levels and different soil moisture conditions. This research is composed of field experiment and green house experiment. Field experiment includes height growth, survival and coverage analysis of cover vegetations (Robinia pseudoacacia L., Lespedeza bicolor Turcz, Arundinella hirta Tanaka var. ciliare Koidzumi.) with 4 fertility level treatments on 3 slopes (Steep: 37。, Moderate: 25。, Gentle; 17。) during dry season (1 April-30 June) and wet season (1 July-10 September). At the same time temperature, relative humidity and precipitation were measured to understand the environmental changes. Soil moisture conditions were measured with soil moisture meter with 24 soil cells. Green house experiment comprised height, fresh weight and dry weight measurements of cover vegetations with 4 fertility levels and 3 moisture conditions for 70 days. The results extracted from experiments are as follews. 1. Cover vegtations have 3 patterns of water requirement at the early stage of growth. a) Robinia type has high water requirement and weaker drought resistance. b) Lespedeza type has low water requirement and stronger drought resistance. c) Arundinella type has moderate water requirement and weaker drought resistance. 2. The vegetations have different optimum fertility levels in different soil soisture supply condition. a) Robinia needs a low fertility level in dry condition and a high level in wet condition. b) Lespedeza needs only low fertility level in all conditions. c) Arundinella needs a low fertility level in dry condition and a high level in wet condition. 3. The efficiency of water use (Water/1g dry weight) by fertility levels is different from one another. Robinia and Arundinella have a good efficiency at low fertility level in dry condition and at high fertility level in wet condition. Lespedeza has a good efficiency at low fertility level in all conditions. 4. P₂O_5 requirement of Robinia and Lespedeza is high, but that of Arundinella is low. Soil moisture condition has a great influence on P₂O_5 absorption in dendued forest land. Once Vegetations are established on suitable sites with optimum fertitity level according to different moisture condition, even the small amount of soil water in denuded land can he used with high efficiency and the effect of fertility treatment can be maximized.

청년층의 소득 및 자산 감소에 따른 주택구입능력 변화와 구입 가능한 주택규모 추정

이수욱(Lee, Soo Wook),김태환(Kim Tae Hwan) 한국부동산원 2016 부동산분석 Vol.2 No.1

이 연구는 최근의 주택시장 변동은 저성장, 저금리, 저출산 등과 더불어 고용 불안과 소득대비 높은 주택가격, 월세 등 주거비부담 증가에 따른 젊은 층의 주택구매력 약화 등이 원인이었다고 보고, 시장불안 완화의 방안을 수요자 특히, 주택시장의 주요 수요층인 25~39세 청년들의 주거안정을 통해 찾고자 하는 데 목적이 있다. 이를 위해 2014년 현재 25~29세인 청년들의 소득과 순자산 변화를 가정한 4가지 시나리오를 설정하고, 시나리오별로 이들의 주택구입능력변화와 구입 가능한 주택재고 규모를 분석 및 추정하였다. 분석 결과는 첫째, 10년 후인 2024년에도 서울, 경기, 울산, 부산 등에 거주하는 25~34세의 중 · 저소득층 가구의 주거불안이 타지역 거주자에 비해 상대적으로 더 클 것으로 나타났다. 둘째, 생애최초주택구입연령대에 해당하는 35~39세 청년가구의 경우 2014년 기준으로 구입 가능한 주택재고 및 매물의 경우, 시나리오별로 주택가격이 수도권은 3.8억 원~3.0억 원, 비수도권은 3.5억 원~2.8억 원이 청년층이 접근가능한 적정한 가격이었으나, 이들 가격대의 재고가 서울은 시나리오별로 56~41% 수준, 경기는 84~73%, 부산 92~79%, 울산 88~75% 수준에 불과할 것으로 전망되었다. 셋째, 청년층의 주택구매력 약화의 가장 큰 요인은 월세 때문이며, 다음으로 취업률 하락과 소득증가율 둔화 그리고 경제성장률 둔화의 순이었다. 이 같은 영향에 의한 청년층의 주택구입능력 저하는 수도권, 비수도권 지역에 관계없이 나타났다. 이는 주택구입핵심 계층으로 분류하고 있는 청년층의 주택수요가 더 빠르게 감소할 수 있으며, 이럴 경우 적지 않은 충격이 주택시장에 순차적·지속적으로 가해질 수 있음을 시사하는 것이라 할 수 있다. 따라서 분양 혹은 공공 및 민간임대에 관계없이 이들을 위한 주택을 추가적으로 더 공급해야 할 필요가 있고, 지역별 · 계층별로도 차별화된 주택수요 진작책과 공급 정책이 필요하다. 특히 서울과 경기, 부산 등의 지역에는 중 · 저소득층의 25~34세 청년층 가구를 위해 저렴한 주택을 지속적으로 추가 공급할 필요가 있다. Recently, Korean housing market is going through a rapid shift due to demographic and economic changes. In the era of low growth, employment is unstable; housing price is high compared to income; and housing expenses are burdensome because monthly rent is increasing. All these factors weaken the housing purchasing power of the mid-20s to 30s, which further leads to an unstable housing market. In this sense, the research aims to propose measures and recommendations to improve their purchasing power. Followings are the main findings of the analysis. First, among the mid-20s to 30s whose age is in between 25 to 39 years, the 25 to 34 years’ housing demand were sharply decreased due to the change in employment and income. Their housing expenses increased in a great deal. Second, the analysis on the mid-20s to 30s’ affordable housing price shows that the mid- and low-income households whose age is in between 25 to 34 years, living in Seoul, Gyeonggi, Ulsan, and Busan suffer from higher housing unstability. Third, mid- to long-term and comprehensive plan needs to be implemented for housing stability of the mid-20s to 30s.

산성우에 대한 산림생태계의 민감도 및 자정기능 (Ⅰ) - 항우의 (降雨) 산성화도와 (酸性化度) 식생 활력도 ( TVI ) 를 중심으로 -

이수욱(Soo Wook Lee),장관순(Kwan Soon Chang) 한국산림과학회 1994 한국산림과학회지 Vol.83 No.4

This study has been conducted to give some ideas for reasonable ecological management of Taejon city and its adjacent forest ecosystem against the effect of acid rain. Rain monitoring points to analyse its components represented 1 point in industrial area, 4 points in commercial area. 4 points in residential area, and 5 points in suburban area and forest survey was done in 7 forest sites adjacent to rain monitoring points. Transformed vegetation index(TVI) based on Landsat TM data was analysed far forest area. Taejon area was seriously contaminated by air pollutants and average concentration of anions in precipitation were 20.16㎎/ℓ for SO₄^(2-). 3.65㎎/ℓ for NO₃^-, and 3.09㎎/ℓ for Cl^-. Anion in precipitation were 1.09㎎/㎡/month for SO₄^(2-). 0.23㎎/㎡/month for NO₃^-, and 0.20㎎/㎡/month for Cl^-. Cation in precipitation were 0.14㎎/㎡/month for Ca^(2+), 0.10㎎/㎡/month for NH₄^+, 0.08㎎/㎡/month for Na^+, 0.07㎎/㎡/month for K^+, and 0.08㎎/㎡/month for Mg^(2+). The region with the highest concentration of SO₄^(2-). NO₃^-, and Cl^- in rain was industrial area. SO₄^(2-), NO₃^-, and Cl^- concentrations in industrial area were 43.08, 3.88, and 3.64ppm, respectively. Forest soil showed strongly acidic ranging pH4.16-4.94. Transformed vegetation index (TVI) were 3.11 in Dangsan, 4.00 in Kyechoksan, 4.13 in Bomunsan, 4.18 in Kabhasan, 3.34 in Bongsan. 4.13 in Sikchangsan, and 4.20 in Seongchisan. Dangsan forest located near in industrial area showed the lowest TVI.