燃料林造成事業의 費用收益分析

李麗夏,鄭燦吉 建國大學校附設 農業資源開發硏究所 1980 論文集 Vol.5 No.-

1. The Korean Government has put massive effort to protect and reforest the mountains since her independence in 1945. Without adequate alternative means of fuel supplies, however, farmers and firewood dealers could not help stop illegal cutting of the forest woods. Recognizing the necessity of alternative ways of fuel supplies the Government started to establish 850 thousands hectars of fuelwood plantations in 1959 with an aim to arrange farm fuels through the establishment of fuel forests, contributing to the prevention of forest demages. The program was accomplished in 1977, totalling 643 thousand hectars planted in terms of area which is less than as planned by 207 thousand hectare,after many years of trial and errors. Of 643 thousand hectare of the fuelwood establishment, 50 thousand hectares were carried out in 1976,and 127 thousand hectare in 1977 respectively. Part of the necessary funds for the project was provided by IBRD loaning during 1976 and 1977 years. Shape of forest is visibly improving in re cent years. 2. The present status of the Village Forestry association system as of the end of October, 1977 is that a total mambers of the VFA are amounted to 2,250,000. There are more 21,109 VFA and there associations organize 141 City and County Forestry Association Unions, these organizations resemble the administrative organization system and become to have cooperation and connection with administrative system. 3. The total number of households of the 36 sample Villages was 4,085. Average number of households per village was 113. Average family number per household was 5.7 person which was very high. Of the total households 3,624 households were farm households and the rest nonfarm households. This comprises the ratio of 89 percent for the farm households and 11 percent for the non-farm households. Relatively high ratio of the farm households indicates that rural households in Korea are heavily dependent upon farming. Members of Village Forestry Association were 3,839 which amount to 93 percent of the total household surveyed. Of the total VFA member households, 916 households were forest land owners and 2,741 households did not possess their own forest land. 4. A total land area of the sample Villages was 19,789,871 hectare consisting of 4,323 hectare of cultivation land 2,936 hectare of upland, and 10,807 hectare of forest land. An average land area per Village was about 300 hectare. 5. Of 10,807 hectare of the forest land the share of fuelwood plantation was 2,962 hactare which amounts to 27.4 percent of the total forest land of the sample villages. Of the tota plantation area 1,877 hectare which amounts to 631.4 percent was established before 1976 and 1,084 hectare which is 36.6 persent was planted since 1973. 611.6 hectare which amounts to 20.6 percent of the total fuelwood plantation was established during 1976 and 1977 with IBRD loans. Amount 20 percent of the fuelwood plantation area which was established before 1973 was disused and considered to result in a great waste of resources. 6. Varieties of the fuelwood species are regidar pine, acasia, alter, acasia-alter mixed forest and bush clover. The most preferable species among VFA members was rigidar pine due to its strong adaptability to environment and fast growth. Looking at the fuelwood plantation area established before 1973 by fuelwood species acasia amounted to 38.4 percent rigidar pine 50.7 percent, alder 6 percent,and other 41.8 percent. Of 190 hectares planted in 1974 acasia amounted to 33 percent, rigidar pine 36 percent, alder 17 percent, and bush clover 5 percent. Of 204 hectare established in 1975 acasia was 36 percent, rigidar pine 21 percent, alder 34.7 percent, and bush clover 7.8 percent. Of 290 hectare planted in 1976 acasia amounted to 23.3 percent, rigidar pine 40.4 percent, alder 26.9 perpent, bush clover 2.8 percent, and other 6.5 perpent. Of 374 hectare planted 1977 acasia amounted to 22.4 percent, rigidar pine 41.8 percent, alder 15.7 percent, bush clover 15.2 percent, and other 4.9 percent. According to the figures the rigidar pine has the largest planted area except 1975. On the basis of the percentage of the plantation area the rankings among fuelwood species are rigidar pine, alder, acasia, and bush clover. 7. Ninetynine percent of fuelwood plantation in terms of hectare nearby mountains from villages and other along roads and the edge of streams. The ownership of the site planted by fuelwood species is mostly private owned which amounts to 90 percent. The owners of the plantation site have to render their tenure rights to VFA to establish fuelwood plantation by law if the County office designate the site for fuelwood planation. The fuelwood plantation is established and managed by VFA with voluntary labor of VFA members. The harvested products will be shared by VFA and the site owners with 9:1 ratio. 8. The servival rates of planted tree ranged from 75 percent to 95 percent and the reforestration of nearby forest is closely visible fuelwood raising status varied widely depending upon soil,light,location,and management of the plantation site. Application of fertilizer,particularly, seems to be very important to raise fuelwood in good condition. Among the 36 sample Villages 30 Villages have applied fertilizers after the establishment of the fuelwood plantations. After the plantation of fuelwood aftercares such as weedings, tendings,fertilizations are carried out for 2∼3years by the members of VFA, voluntarily, with no wages paid except fertilizers subsidied the Government. For autonomus fuelwood plantation protection a patrol team is organized by the VFA members. The inturn patrol team consisting of two VFA members makes intensive patrols during the season of fall through the spring of the following year which forest damages are heavily expected. These patrols have served for the prevention of collecting illegally forest products, control of destructive actions against forest facilities, prevention of forest fire, prevention of illegal hunting, etc. There were no villages hired full time patrolmen among the 36 sample villages. All chiefs of the VFA surveyed were serving without pay. It takes generally 4∼5years to harvest fuelwood after planting the seedlings. Weeding is taking place every year until the havest time comes, and the remains are not remains are not collected for fuel. They are spreaded and left around the tree for fertilizer. 9. Fuel production from the fuelwood plantation has been considerably low compared to what has been expected. The survey reveals that the average amount of fuel harvest out of the fuelwood plantation was 1,71 M/T per hectare. Expected or planned fuel production was fire M/T per hectare. The highest production turned out to be 10 M/T per hectare while the lowest 0.1 M/T. 10. The principal benefits of the fuelwood project would be: (a) production of forest fuel which would replace illegal cutting and gathering of timber and other forest products. (b) labor saving in collecting fuel. (c) creation of permanent timber producing forests as a secondary purpose of the fuelwood plantation projects, and consequent reduction of soil errosion and flood protection. (d) increase inseedling farmer's income and creation of employment opportunities for the labor intensive seedling farms. (e) beautification of mountains and villages, and institutional building at village level leading to self reliance. 11. Quantitative measurement of direct benefits a and b is attempted. There are no explicit markets for fuetwood rural area any more. However fuelwood, more specifically trimmed tree branches sometimes are bought and sold among the residents in a village. Price of the fuelwood is around 1,000 won per 60㎏,a loadful of “gike”(A-frame). It is assumed that full yield would be reached in eighth year and would equal 5 tons/ha. Yields would build up 0.5 ton in forth year, 1 tons in fifth year, 2 tons in sixth year, 4 tons in seventh year and there-after 5 tons/ha until 20th year. There will be no production until fourth year. During years 1 to 3, there would be a certain amount of grass and weeds produced but usually it is left on the site for fertilizer and value of this would be merely equal to the opporunity cost of labor maintaining the fuelwood plantation. 12. When there were no fuelwood plantations, a household had to spent average 41 days per annum to stock up 1 year fuel requirement during mostly winter time. With fuelwood plantation, a rural household spends about 7 days for a year to serve fuelwood plantation including forest product harvest. Value of time saving may be evaluated as an opportunity costs of labor. 75% of annual average wage rate for man and woman in 1977 was 1,500 Won/day. Labor saving value per ha of fuelwood plantation was estimated to be about 16 days when substracting the effect of 45% composition rate of briquette and agricultural residuals in fuel consumption. Savings of coal resources and agricultural residues did not occur in the survey as country to expected. 13. The cost per ha of plantation establishment is estimated to be around 112,216 Won. Materials, transport and overhead are evaluated at their financial costs. Supervision costs are valued at 4,233 Won/day which is skilled laborer’s wage rate in 1977. Village volunteer labor which comprises 57% of total cash valued establishment cost has been valued at 1,500 Won/day which is 75% of annual average farm wage rate in 1976. The volunteer labor cost is 63,214 Won/ha. 14. The maintenance costs of fuelwood plantation is composed of weeding brushing for the first 4 years and plantation patrol costs. This is valued at 3,047 Won. Production costs may be divided into labor cost for harvest and fertilizer costs. Labor cost is estimated at 2,417 Won per ha and fertilizer cost is 1,303 Won/ha. Therefore, the total production costs for fuel is 3,786 Won/ha. 15. For cost and benefit streams, the rate of return is estimated to be 18.8%. The benefit cost ratio was 2.29 and 1.81 when 12% and 15% discount rates were used respectively. When the fuel production was valued at opportunity cost of labor. 1,500 Won/day, IRR is estimated to be 19.78%. It was assumed that one man can harvest and carry (by A-frame)180㎏/day. The transport distance was assumed to be 1 km.

디젤엔진 代替燃料源으로서의 쉬나무의 造林學的인 特性에 關한 硏究

洪性珏,李麗夏,崔圭洪 建國大學校附設 農業資源開發硏究所 1983 論文集 Vol.8 No.-

쉬나무의 種實油는 디젤엔진의 代替燃料源으로서 그 가능성이 높은 것으로 알려지고 있는 바, 쉬나무의 栽培에 필요한 造林學的 特性을 알기 위하여, 本 硏究는 쉬나무의 自然分布地, 種實 및 木材生産性, 實生苗 및 接木苗 生産方法, 耐寒性度의 季節的 變異에 대해 調査하여, 다음과 같은 結果를 얻었다. 1. 推定年齡이 70∼150年生인 쉬나무들이 南部에서 中部에 이르기까지 넓게. 그러나 宮터, 古宮의 庭園, 農村의 마을 주변과 같이 제한된 지역에 自然相으로 分布하거나, 人工的으로 植栽되어 있는 것으로 판명되었다. 또한 쉬나무는 山麓部의 土深이 깊은 砂質壤土 및 植質壤土의 土壤에서 根萌芽에 의한 몇몇 群狀稚樹와 함께 孤立木으로 자라며, 母樹 주위에는 後代 實生稚樹의 發生이 드물었다. 쉬나무 實生稚樹 및 그 自然分布가 制限된 것은 自然狀態에서 多量의 種子가 野生鳥類의 먹이로 소비되어 버리고, 그 發芽率이 낮은 것이 주요 원인으로 생각된다. 2. 孤立木에서 樹冠面積(水平面積)에 대한 種字量을 推定했을 때, 年間 ha當 755 kg의 種字가 生産되고, 이로부터 264 kg의 種實油가 生産된다. 樹齡이 확인된 몇몇 나무의 경우, 20 年生 나무의 胸高直徑은 14 cm, 70 年生은 25∼26 cm였다. 樹高生長은 直徑生長과 상관없이 胸高直經 14∼83 cm의 나무의 경우 그 樹高는 6∼13 cm의 변이가 나타났다. 대부분의 大徑木이 主幹에 심한 心材腐朽를 일으켰는데, 그 原因이 凍害로 인한 것인지 또는 그외 다른 原因에 의한 것인지는 밝혀지지 않았다. 서울지방에 자라는 70 年生 나무에 있어서 主幹에는 心材腐朽가 있었으나, 14 年生 가지에는 心材腐朽가 없는 것으로 미루어 보아 지나간 14년간 材部柔組織에는 凍害가 없었음을 알 수 있었다. 木材는 전체적으로 보아 直線木理이나 觸單面에서는 放射柔組織을 중심으로 交叉木理를 갖고 木組織은 치밀하며, 氣乾比重은 2 年生에서 0.66, 70 年生에서 0.77이었다. 3. 種皮의 wax狀物質을 10% 合成洗劑 溶液으로 제거시킨 결과 發芽率이 10∼15%에서 80∼95%로 증가되었다. 70 年生 나무에서 얻은 接穗을 2 年生 台木에 切接으로 接木시킨 결과는 성공적이었다. 台木이 굵을수록 接穗의 生長이 좋았다. 4. 種字産地別로 幼苗의 耐寒性度에는 차이가 나타나지 않았다. 이와 같이 耐寒性度의 차이가 적은 것은 이 樹種이 蟲媒花이지만 암꽃과 수꽃의 꽃피는 시기가 다르므로 他家受精이 가능하여 집단간에 遺傳子交換이 될 수 있기 때문인 것으로 解析되었다. 1 年生 苗木은 2 年生 苗木보다 耐寒性度가 더 낮은데 이는 1 年生 苗木의 생장기간이 보다 길기 때문에 材部柔組織의 소수의 細胞가 耐寒性 發達이 늦기 때문에 나타난 것으로 생각되었다. 1 年生 苗木의 凍害防止를 위해서는 겨울동안 땅속에 假植을 하는 것이 가장 좋은 방법이다. To know the silvicultural characteristics of Evodia daniellii, of which the seed oil was known to have the high feasibility of fuel substitution for diesel engine, this study investigated the natural distribution of the tree, the productivity of the seed and wood in the natural condition, the production of the seedlings from the seeds and the grafts, and the seasonal variation in cold hardiness of the seedlings from different provenance. The following results were discussed; 1. It appeared that Evodia daniellii, estimated as old as 70-200 years, are naturally distributed and/or artificially planted widely from the southern part up to the middle part of Korea, but in a limited spot such as the site of an ancient castle, the garden of palace and near rural village, and that the trees are growing as an isolated tree with a few progeny near the mother tree, at the site of good soil depth with sandy loam in the lower part of hillside. The limited natural distribution of this species was attributed to large consumption of the seed by feeding the wild birds and low percent germination in the natural condition. 2. The seed produced annually, as estimated by the amount of seed in an isolated tree per the area projected by the crown, averaged 755kg/ha, resulting in 264kg/ha of the seed oil. In some trees of which the age was able to be identified, the diameter growth at the age of 20 years was 14 cm, and 25 to 26 cm at the age of 70 years. The heigh growth was not consistent with the diameter growth or the age and varied from 6 to 13 meter in the trees of diameter 14 to 83 cm. The main stem of most of large diameter trees showed various heart rot damage of which causes were not clear whether it was brought about by freezing or other incidents. In one 70 years-old tree growing in the northern limit of Korea with serious heart rot in the main stem, the 14 year old branch showed no sign of the heart rot, indicating that there has been no freezing injury on the main branch for 14years. The wood had straight grain over all, otherwise interlocked grain around the ray structure on the tangential section, dense texture, specific gravity (air dried) of 0.66 in two year old stem and of 0.77 in 70 year old stem. 3. Removal of wax like material from the surface of the seed coat with 10% solution of synthetic soap promoted the percent germination from 10-15% to 80-95%. The veneer grafting of the scion from the 70 year old tree to 1 to 2 year old stock was successful. The thicker the stock was used, the better the growth of scion was obtained. 4. There was little difference in cold hardiness among seedlings from different provenance. The little difference could be attributed to the out-breeding mechanism, even though this species is pollinated by insects, in that earlier flowering of the male flower than the female one may allow the gene exchange among the population. One year old seedling was less cold hardy than the two year old one. This might be attributed to the slow development in cold hardiness of the small group of cells in the xylem, which was probably resulted from longer growth period of one year old seedling than the older trees. The cold damage of one year old seedlings could be prevented by transplanting them in the soil temporarily during winter

맥주박 바이오차 처리가 암모니아 배출량에 미치는 영향 평가

이재한(Jae-Han Lee),최하연(Ha-Yeon Choi),박성용(Seong-yong Park),천진혁(Jin-Hyuk Chun),강윤구(Yun-Gu Kang),윤여욱(Yeo-Uk Yun),이기범(Gibum Yi),오택근(Taek-Keun Oh) 한국토양비료학회 2021 한국토양비료학회 학술발표회 초록집 Vol.2021 No.11

암모니아(NH₃)는 대기 중 황산화물(SOx), 질소산화물(NOx) 등과 반응하여 황산암모늄, 질산암모늄과 같은 2차 미세먼지를 생성하는 주요 미세먼지 원인물질이다. 2017년 기준 국내에서 NH₃는 총 308,298 ton year<SUP>-1</SUP> 배출되었으며, 농업부문에서 약 79.3%의 비율로 가장 많이 배출되었다. 토양에 질소질 비료의 시용 시 발생되는 NH₃의 대기로 배출은 토양 내 질소 손실의 원인이 되기도 한다. 바이오차는 넓은 표면적과 표면의 작용기를 가지고 있어 토양 내에서 중금속이나 오염물질 등을 제거하는 특징이 있다. 본 연구는 다양한 온도에서 열분해된 맥주박 바이오차 처리가 NH₃ 배출량에 미치는 영향을 평가하기 위해 실시하였다. 바이오차는 충분히 건조된 맥주박을 300, 500, 700°C에서 각각 1시간 동안 열분해하여 제조하였다. 각 바이오차를 토양에 3% (w w<SUP>-1</SUP>)씩 혼합 후 NH₃ 포집을 위해 자체 제작한 아크릴컬럼에 작토층 높이인 20 cm 까지 토양을 채웠으며, 토양 수분함량은 20%로 조절하였다. 질소질 비료는 작물별 시비처방기준의 배추를 기준으로 요소를 각 처리구에 320 kg ha<SUP>-1</SUP>로 처리하였다. NH₃의 포집은 요소 처리 후부터 약 30일간 실험실 내에서 실시하였다. 배출되는 NH₃는 0.05 N H₂SO₄으로 포집하여, Indophenol blue method로 비색정량하였다. 그 결과, 시험 기간 중 총 NH₃ 배출량은 BB<SUB>700</SUB>처리구가 약 11.83 kg ha<SUP>-1</SUP>로 가장 높게 나타났다. BB<SUB>300</SUB>처리구의 총배출량은 약 7.34 kg ha<SUP>-1</SUP>로 가장 낮았으며, N처리구에 비해 약 30.5% 저감 되었다. BB<SUB>700</SUB>처리구는 N처리구에 비해 NH₃ 총배출량이 약 12% 증가하였는데, 이는 바이오차의 높은 pH에 의한 alkali effect로 판단된다. 실험 후 토양 분석 결과, 모든 바이오차 처리구에서 pH, EC, Av. P₂O<SUB>5</SUB>, T-C, T-N 등이 증가하였다. 특히, BB<SUB>700</SUB>처리구는 처리된 바이오차의 높은 탄소 함량으로 인하여, 토양 내 탄소 함량이 약 3.44%로 가장 높았다. 따라서, 비교적 낮은 온도에서 열분해한 BB<SUB>300</SUB>의 토양 처리가 농경지에서 배출되는 NH₃를 감축할 수 있으며, 본 연구 결과는 실제 농경지에서 배출되는 NH₃를 감축하기 위한 기초자료로 사용될 수 있을 것으로 판단된다.

林木의 年輪成長에 대한 分析

李麗夏 建國大學校附設 農業資源開發硏究所 1977 論文集 Vol.3 No.-

비교적 좋은 林木度를 維持하고 있는 58年生의 赤松과 젓나무의 混淆林에서 각각 6本의 標本木을 伐採하여 地上 0.2m의 根元部 圓板과 地上 4m마다의 圓板을 採取하여 個體別로 令階別 年輪成長을 調査하여 이들의 相關關係와 生長周期를 調査한것이다. 1. 各樹令間의 相關은 비교적 높은 相關係數로 나타나서 赤松은 20年階에서 0.7이고 잣나무에선 10年階에서 0.7이상이었다. 2. 根株年輪과 全體圓板의 年輪平均値와는 높은 相關을 나타내고 있다. 3. 赤松 個體間의 成長差異는 그 成長振幅이 큰데 反하여 젓나무의 成長은 비교적 고르게 正常的인 成長을 하고있다. 4. 年輪成長의 周期는 젓나무와 赤松間에 큰 差異없이 거의 같은 時期에 나타나고 있다. Each six sample trees of Korean red pine(Pinus densiflora S.et.2) and Korean fir(Abies holophylla Max.) were cut at mixed forest stand of which stand density was fairly high. Root colar disk at 0.2m above ground and the disks at every 4m above ground were collected. The annual ring growth of the sample trees was measured by each age class.The correlation among the annual ring growth was calculated and the interval of growth period was obtained. Following results were obtained: 1.Relatively high correlation coefficient were obtained among the growth at each age. The coefficient were above 0.7 among age class of 20 in Korean red pine and among age class of 10 in Korea fir. 2. High correlation was shown between the growth in root colar disk and in other disks. 3. Variation in annual ring growth among individual Korean red pine was high, on the other hand that of Korea fir was low. 4. Periodic growth of Korean red pine and fir appeared at some time interval.

林木生長과 個體間 競爭效果 推定에 대한 考察

李麗夏 建國大學校附設 農業資源開發硏究所 1980 論文集 Vol.6 No.-

This study was carried out to know the difference in growth and degree of competition between trees of thinned and unthinned stands. Annual increment and total growth were obtained from the cores sampled at the DBH. The correlation between adjacent individual trees was investigated. 1. The correlation between radius growth and basal area was used to estimate the degree of competition among individual trees. 2. To estimate the degree of competition, the correlation between two individual trees was better method them that among every tree. 3. Up to 7 years after planting, no competition between individual tree occurred and the high position correlation was shown. 4. High degree of competition was observed 9 years after the planting, as the correlation coefficient was getting smaller. 5. As the growth of the total stand increased, the degree of competition among individual tree also increased.

밤나무 耐寒性品種 選拔에 관한 연구

李麗夏,趙台煥,洪性珏 건국대학교 1976 學術誌 Vol.20 No.2

32 cultivars of chestnut were collected at the Kyunggido Forest Experimental Station, Oh-San, Kyunggido, Korea on November and December, 1976. The freezing resistance of winter bud, cambium and xylem parenchyma of the cultivars was measured to select out freezing resistant cultivars under the condition of early winter in Korea. The winter bud showed lowest freezing resistance among tissue parts. The xylen parenchyma attained relatively higher freezing resistance than the cambium did. On the basis of the freezing resistance of winter bud eleven cultivars which showed relatively high freezing resistance were selected among 32 cultivars of chestnuts. Again on the basis of the freezing resistance of cambium which is often one of the critical factors in winter damage, another eleven freezing resistant cultivars were selected. The eight cultivars which showed both freezing resistance of winter bud and cambium were chosen. These were in order from highest to lowest selected freezing resistant cultivars, wild chinese chest nut, Dan-Taeck, OK-Kwang, Bong-Eeh, Chuk-Pa, Da-Ap, Mahn-Juk, Ahn-Goon.

잣나무 幼齡林分의 樹高成長에 關한 硏究

李麗夏 건국대학교 1974 學術誌 Vol.18 No.1

To summarize this survey, the following conclusions were made: 1) The Main shoot growth of tree was surveyed to help the silvicultura' tendering of young Korean white pine forest. 2) The survey had been continued for 3 years continuously, in random sampling of 100 trees among fixed sample plot. 3) The most active period of annual height growth is Mid May. 4) About 90% of annual main shoot growth of this stand were found out to be done from May to June. 5) Annual main shoot growth is ranging from 29.5cm to 49.3cm. 6) The main shoot growth for one day, in the most active period of main shoot growth, is 1.15cm.

林分材積推定方法間의 精度比較

李麗夏,金東根 建國大學校 附設 農業資源開發硏究所 1993 農資源開發論集 Vol.18 No.-

建國大學校 農科大學 演習林(京畿道 廣州 所在)의 2林班 가小班의 낙엽송과 잣나무 混淆林 700㎡(0.7ha)의 面積에서 몇 가지의 標本抽出方法을 이용하여 精度를 비교하였다. 이상의 조사결과를 요약하면 다음과 같다. 1) 이 조사에서는 우리나라에서 많이 이용되고 있는 標本抽出方法中 任意抽出法, 系統的 抽出法, 그리고 層化抽出法 등의 3가지 방법을 선정하여 標本을 추출하여 母集團의 材積을 추정한 후 이들의 정도를 비교하였다. 2) 母集團과 5개의 標本點間에는 有意性이 나타나지 않았으며, 또한 母集團과 3가지 標本抽出方法에 의한 標本調査間에는 전혀 有意性이 나타나지 않았다. 3) 3가지 標本抽出方法間의 精度는 任意抽出法, 層化抽出法, 그리고 系統的 抽出法 順으로 높게 나타났다. This survery was estimated in The Kon-Kuk University Experiment Forests(Gwang-ju, Gounggi-do) for mixed forest(Larix leptolepis Gordon and Pinus koraiensis S. et Z., 7,000㎡) to compare the accuracy of some sampling method. The results obtained are summarized as follows; 1. The accuracy were compared under three sampling method such as random sampling method, systematic sampling method, and stratified sampling method. 2. In the survey, significant difference between population and five sampling points was not shown, and also there was no significant difference between population and three not shown, and also there was no significant difference between population and three sampling methods. 3. The accuracy of sampling methods was shown in order of rendom sampling method, stratified sampling method, and systematic sampling method.

林分의 過去 成長量 推定에 關한 硏究

李麗夏 건국대학교 생명과학연구원 1994 생명과학지 Vol.1 No.-

잣나무林에 대한 林分構造를 분석하여 이 林分의 과거 변화되어온 과정을 파악하여 이를 새로운 경영에 반영하기 위하여 林分解析을 실시한 것을 요약하면 다음과 같다. 1) 林分內 標準이 될 수 있는 林分은 標準地로 선정하고 標準地面積은 1,000㎡로 설정했다. 2) 標準地內 林木에 대하여는 每木調査를 실시하여 本數配分表를 작성하고 이에 따른 標準木을 분배 추출하였다. 추출한 標本木數는 다음의 근사식에 의하여 결정했다. N=(2Cv/P)2×(1-p2) 3) 추출된 林木에 대하여는 이를 伐採하여 樹幹析解을 하기 위하여 材長 2m로 절단한 것을 Huber式에 의하여 材積을 계산하고 지상 0.0m부위의 年輪數에 의하여 추정된 林齡은 33년생이었다. 4) 수확표와 비교한 標準地林分의 地位指數는 8이었다. 5) 樹幹析解한 林木의 각 齡級內의 재적은 Xi=a+bYi의 일반식에 의하여 추정했으며 그 抽出率은 현재에서 과거로 소습할수록 낮아지며 材積間의 相關係數는 각 繼時點에서 멀어질수록 적어졌으며 가장 낮은 상관관계는 0.51이였다. 6) 實材積에 대한 Yates의 방법을 응용하여 계산된 材積表材積의 보정은 推定誤差率이 1.8%이고, 推定實在的의 推定誤差는 0.0004㎥였다. 7) 林分材積表 추정은 該當수확표 33齡級 환산한 평균재적은 175.842㎥에 대하여 plot의 ha당 林分材積은 158.394㎥로서 재적비는 90%에 달하고 있다. This study aimed to elucidate the successive change of the preview stand construction of which was made artificially, Since any working data were not recorded. This survey was carried out on the 33 years-old Korean white pine(Pinus koraiensis s. et z), the procedures and results of this stand analysis were as follows; After-timber cruise, in plot of 1,000㎡ in area, sample trees of respective diameter classes were chosen and the number need for stem analysis were determined according to the following formula. N=(2Cv/P)2×(1-p) Where Cv is the coefficient of variation of the present stand. P is the aimed precision. p is a correlation coefficient of successive volume at a time, When above precision is claimed. Trees to be used for stem analysis were sectioned into 2m interval and its volume was calculated by using the Huber's formula, the age of all trees was 33 years-old as a count of the annual rings of the ground level disk. The Value of the forest site index was 8. The Volume estimation of the past stand each age class was made by the formula x1=a+byi and the positive correlation between the estimation rates and the stand ages were observed. The error percentage of calibration between actual volume and volume table was 1.8% and the standard error of the estimated actual volume was 0.0004㎥. The average volume per ha of plot in 33 years of age class is 175.842㎥ and when this figure was compared with 158.394㎥ of the concerned yield table, and average stem volume was 90% of the concerned yield table which means the value of the yield table was larger.

林木의 年次成長量推定에 관한 硏究

李麗夏 建國大學校附設 農業資源開發硏究所 1976 論文集 Vol.2 No.-

比較的 좋은 林木度를 維持하고 있는 잣나무林分에서 任意抽出한 60本의 標準木을 伐採하고 地上 0.2m 의 根元部 圓板을 採取하여 個體別로 齡階別 成長量을 調査하여 伐期成長量을 早期 推定한 것이다. 이들 早期成長量 推定은 다음과 같은 統計的인 分析方法에 의하여 이루어졌다. 1. 標準木選定은 n=( ?? )²(1-ρ)²의 近似式에 의하여 本수를 決定하고 林意抽출했다. 2. 伐採時까지의 總成長量과 各樹齡에서의 總成長量과 年次別 相關分析을 했다. (Table 1과 Fig.1) In a stand of Pinus Koraiensis with fairly good stand density, 60 random sample trees were cut and the root colar disks were collected. The final growth was estimated by measuring the growth of the disk of each age. The results obtained are as follow: 1. The annual correlation between final increment and total increment at each age is shown in table 1. 2. The correlation coefficients among the successive age classes are relatively high, for example over 0.7 after the 19 years age class. 3. The analysis of the regression of final increment to total incfement at each age shows that the regression variation of the total increment at each age arter 19 year to the final increment is over 50%. 4. In the juvenile-mature relation of the tree, the final increment is able to be estimated from the early total increment after about 20 years.