• Journal of Forest and Environmental Science
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• 제25권1호
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• pp.1-24
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• 2009

Teak (Tectona grandis) is one of the most valuable timber yielding species in the world, with predominant distribution in tropical or sub-tropical countries. However, natural teak available only in few countries like India, Myanmar, Laos People's Democratic Republic and Thailand. Teak grows well in deep, well-drained alluvial soils, fairly moist, warm, tropical climate with pH ranges from 6.5-7.5. Teak is cultivated in many Asian, African and South American countries for timber production. The global teak plantations are estimated to be three million hectare with major share in India (44%) followed by Indonesia (33%). India is considered as richest genetic resources of teak with large areas of natural teak bearing forests (8.9 million ha), plantations (1.5 million ha), clonal seed orchards (1000 ha) and seed production areas (5000 ha). The studies on diversity of teak populations showed that teak is an out crossing species with major portion of diversity present within the populations. The productivity and quality of teak timber varies depending upon the site and environmental conditions. Teak wood is moderately heavy, strong and tough,straight grained, coarse textured and ring porous with specific gravity varies from 0.55 to 0.70. The sapwood is white to pale yellow in colour and clearly demarcated while heartwood is dark brown or dark golden yellow in colour. Teak is one of the most durable timbers in the world, practically, impervious to fungus and white ant attack and resistant to decay. Teak wood is used in ship and boat constructions, furnitures and aesthetic needs. Genetic improvement programmes have been undertaken in countries like Thailand, India, Malaysia and Indonesia. The programme includes provenance identification and testing, plus tree selection and clonal multiplication, establishment of seed orchards and controlled hybridization. Several aspects like phenology, reproductive biology, fruit characteristics, silvicultural practices for cultivation, pest and diseases problems, production of improved planting stock, harvesting and marketing, wood properties and future tree improvement strategy to enhance productivity have been discussed in this paper.

• 한국수산과학회지
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• 제44권3호
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• pp.290-297
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• 2011

The phenology of Campylaephora hypnaeoides J. Agardh and optimal conditions for carpospore release, growth and reproduction were examined in the field and in the laboratory from January to December 2007. In the field population of C. hypnaeoides, approximately 50% of the plants were vegetative during the study period. Additionally, the percentages of carposporophytes and tetrasporophytes were maximal in April (37%) and June (57%), respectively. Maximum growth in plant length, dry weight, and hook number coincided with the tetrasporophyte reproductive peak in the field. In culture, carpospore release, sporeling growth and reproduction were affected by environmental factors such as daylength, temperature, and salinity. The liberation of carpospores was maximum under continuous light and at a combination of $15^{\circ}C$ and $10\;{\mu}mol$ photons $m^{-2}\;s^{-1}$. Maximum growth of tetrasporophyte sporelings occurred at a combination of $20\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and $25^{\circ}C$. However, the growth of gametophyte sporelings was maximal under $40\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and in a combination of $20^{\circ}C$ and 35 psu. The tetrasporophyte sporelings were grew faster than gametophytes, indicating that gametophyte- and tetrasporophyte-sporelings have different physiological responses to irradiance and temperature. Tetrasporangial branches and cystocarps of C. hypnaeoides were produced from carpospores and tetraspores within 1 month, and they were stimulated at high temperature and irradiance levels. In conclusion, C. hypnaeoides should be seeded using carpospores during early winter (November-December) because cystocarps are easily identified by fishermen, and tetrasporophytes grow faster than gametophytes.

• 한국농공학회논문집
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• 제60권4호
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• pp.63-72
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• 2018

The main function of an agricultural reservoir is to supply irrigation water to paddy rice fields in South Korea. Therefore, the operation of a reservoir is significantly affected by the phenology of paddy rice. For example, the early stage of irrigation season, a lot of irrigation water is required for transplanting rice. Therefore, water storage in the reservoir before irrigation season can be a key factor for sustainable irrigation, and it becomes more important under climate change situation. In this study, we analyzed the climate change impacts on reservoir storage rate at the beginning of irrigation period and simulated the reservoir storage, runoff, and irrigation water requirement under RCP scenarios. Frequency analysis was conducted with simulation results to analyze water supply probabilities of reservoirs. Water supply probability was lower in RCP 8.5 scenario than in RCP 4.5 scenario because of low precipitation in the non-irrigation period. Study reservoirs are classified into 5 groups by water supply probability. Reservoirs in group 5 showed more than 85 percentage probabilities to be filled up from half-filled condition during the non-irrigation period, whereas group 1 showed less than 5 percentages. In conclusion, reservoir capacity to catchment area ratio mainly affected water supply probability. If the ratio was high, reservoirs tended to have a low possibility to supply enough irrigation water amount.

• 대한가정학회지
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• 제43권6호
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• pp.61-79
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• 2005

The purpose of this study was to determine the leading causes of choosing to be single through in-depth interview. In the study I applied Hermeneutic Phenology to clarify the relationship between the past experiences and values of the subjects. I analyzed the leading causes that have drawn them to stay single, and the gender differences on the two subjects. The causes of being single were divided into two categories; personal factors and socio-environmental factors. The personal factors were standard value by birth order, expectation from parents, overcoming economic difficulty, and lack of interest toward the opposite sex. The socio-environmental factors were achievement at work, and ease of living. Staving single is not a special way of life. As found in the study, the cause of being single is not determined at birth, but rather results from being raised to be single in a way. The main cause of being single was basically based on the environment in which they were raised including parents' attitudes, economic situation, and sibling order We are living in a society of diversity. Being and staying single is a personal choice, that is one aspect of diversity. Therefore we need to widen our vision to accept the single life as one of the normal life styles and one for special treatment. We have to approve of other people's life styles as long as of causes no harm for the development of society. On the other hand, we need to be more serious about the family itself and having family. Finally I think we need to develop various family programs targeted at a diverse range of families rather than only at the normal family.

• 한국응용곤충학회지
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• 제44권3호
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• pp.231-235
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• 2005

본 연구는 제주지역에서 계절초기 벚나무깍지벌레 방제적기를 구명하고자 월동성충의 산란시기 및 부화약충의 이동시기를 조사하였으며, 이 자료를 기존에 보고된 뽕나무깍지벌레 적산온도 예찰 모형에 적합하여 비교 검토하였다. 벚나무깍지벌레 암컷 월동성충은 4월 중하순부터 산란을 시작하여 5월 상순에는 그 알이 부화하기 시작하였으며, 5월 중순경 부화약충의 이동이 가장 활발하였다. 이와 같은 봄철 벚나무깍지벌레 발생시기는 우리나라 남부지역 및 일본 중부지역에서 보고된 뽕나무 깍지벌레 발생시기와 대체적으로 일치하였다. 또한 봄철 뽕나무깍지벌레의 >50% 부화 난괴 발생비율(y) 추정 적산온도 모형(y=1/[exp(-(-a+bx))];, a=-18.80, b=0.073; x=적산온도, 1월 1일부터 발육영점온도 $10.5^{\circ}C$ 적용)은 벚나무깍지벌레 부화약충 이동시기와 일치하여 봄철 벚나무깍지벌레 방제적기 추정에 유용하게 이용될 수 있을 것으로 판단되었다.

• 한국자원식물학회지
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• 제27권1호
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• pp.95-101
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• 2014

본 연구는 고사리삼과에 속하는 제주고사리삼 잎의 생장 패턴 및 식물계절학적 특성을 파악하기 위하여 실시하였다. 제주고사리삼은 지하경을 이용하여 무성번식 하는 종으로서 한 클론의 길이는 52 cm까지 자랐으며, 뿌리가 생장하는 동안 새로운 근경과 잎이 형성되었다. 제주고사리삼 잎은 7월에 출현하기 시작하였으며, 생장은 기온이 높고 강수량이 많은 7월 ~ 9월 동안에 활발하게 이루어졌다. 잎은 10월까지 생장을 마치고 이후 성숙된 포자낭에서 포자가 방출되기 시작하였으며, 11월부터 잎의 노화가 시작되어 이듬해 2월이 되면 대부분의 포자엽과 영양엽이 노화되고 4월 이후에는 잎 전체가 시들어 없어졌다. 이와 같이 제주고사리삼 잎의 생육기간은 7월에서부터 이듬해 4월까지 10개월이었으며, 노화의 시기는 자생지 마다 다소 차이를 나타냈다. 이는 자생지의 미세 환경의 차이에 의한 것으로 생각되며 이에 대한 연구가 진행되어야 할 것으로 판단된다.

• Journal of Ecology and Environment
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• 제30권2호
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• pp.143-149
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• 2007

To certify predictability for the times of phenological stages from cumulative air temperature in springtime, the first times of budding, leafing, flower budding, flowering and deflowering for 14 woody plants were monitored and air temperature was measured from 2005 to 2006 at Namsan. Year day index (YDI) and Nuttonson's Index (Tn) were calculated from daily mean air temperature. Of the 14 woody species, mean coefficient of variation was 0.04 in Robinia pseudo-acacia and 0.09 in Alnus hirsuta. However, mean coefficient of variation was 0.30 in Forsythia koreana and Stephanandra incisa and 0.32 in Zanthoxylum schinifolium. Therefore, the times of each phenological stage could be predicted in the former two species but not in latter three species by two indices. Of the five phenological stages, mean coefficient of variation was the smallest at deflowering time and the largest at budding time. In five phenological stages, mean coefficient of variation of YDI was in the range of $0.11{\sim}0.21$ but that of Tn was in the range of $0.15{\sim}0.26$. Therefore, the former was a better index than the latter. Of the species-phenological stage pair, coefficient of variation of YDI was 0.01 in Acer pseudo-sieboldianum - flower budding and below 0.05 in 11 pairs, whereas the YDIs over 0.40 were 4 pairs comprising of Prunus leveilleana - budding (0.51). Coefficient of variation of Tn was 0.01 in A. hirsuta - budding and below 0.05 in 8 pairs. The Tns over 0.40 were 5 pairs comprising of F. koreana - flower budding (0.66).

• 한국환경복원기술학회지
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• 제14권2호
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• pp.47-57
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• 2011

This study monitored forest plant species vulnerable to climate change in Jiri Mountain, one of Korea's representative alpine regions, in order to securely preserve plant genetic resources susceptible to climate change and to utilize the results as basic data for bioclimatology prediction and management on a long-term basis. A majority of indicator plants tended to blossom one week to one month later in 2010 than in 2009. As with the blooming dates, the falling dates of blossoms became later in most species, with the exception for Weigela florida and Oplopanax elatus. Leaf bursting as well fell on later dates in a majority of species excluding Carpinus laxiflora and Cupressus sempervirens, displaying the most obvious differences among the data of analysis of the 2009-2010 physiological cycle changes. It is believed that was due to the fact that temperatures in February, March and April, which affect plants' blossoming and leaf bursting, were lower in 2010 than in 2009 and that cold temperatures in the winter lasted for a longer period in 2010 than in 2009. The dates of leaves being changed to red were similar in 2009 and 2010 by being or later or earlier by several weeks in 2010 than in 2009 without any regularity. Most species' leaves began to fall at similar dates in 2009 and 2010 or at later dates by one to two weeks in 2010 than in 2009. The temperature differences in late 2009 and late 2010 were not so large, resulting in similar dates of falling leaves, and gaps in several indicator plants' physiological cycles without any regularity can be attributed to each individual plant's physiological and environmental characteristics.

• 한국산림과학회지
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• 제25권1호
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• pp.1-12
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• 1975

남한지역(南韓地域)에 있어서 80개소(個所)의 기상측정치(氣象測定値)를 기초로 하여 각지점(各地點)의 온도지수(溫度指數)와 한랭지수(寒冷指數)를 계산(計算)하고 이것을 도상(圖上)에 나타내었으며 등지선(等指線)을 추적(追跡)하여서 작도(作圖)하였다. 이때 30년간(年間)의 기상인자(氣象因子)를 평균(平均)하였다. 현재(現在) 일반적(一般的)으로 우리가 시인(是認)하고 있는 삼림대(森林帶)의 경계(境界)는 온량지수(溫量指數)보다는 한랭지수(寒冷指數)의 등지선(等指線)과 더 관련(關聯)이 있는 것으로 해석된다. 몇 조림수종(造林樹種)에 대한 온량지수(溫量指數)에 대(對)한 검토를 했다. 이와같은 내용은 생물기후(生物氣候), 재배가능지(栽培可能地)의 추측(推測) 생태(生態)등의 사실(事實)을 설명하는데 도움이 될 자료(資料)가 될 것으로 생각된다.

• 대한원격탐사학회지
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• 제20권3호
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• pp.175-188
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• 2004

The objectives of this study were to estimate leaf area index (LAI) as a function of image-derived vegetation indices, and to compare measured and estimated LAI to the results of crop model simulation. Soil moisture, crop phenology, and LAI data were obtained several times during the 2001 growing season at monitoring sites established in two central Missouri experimental fields, one planted to com (Zea mays L.) and the other planted to soybean (Glycine max L.). Hyper- and multi-spectral images at varying spatial. and spectral resolutions were acquired from both airborne and satellite platforms, and data were extracted to calculate standard vegetative indices (normalized difference vegetative index, NDVI; ratio vegetative index, RVI; and soil-adjusted vegetative index, SAVI). When comparing these three indices, regressions for measured LAI were of similar quality $(r^2$ =0.59 to 0.61 for com; $r^2$ =0.66 to 0.68 for soybean) in this single-year dataset. CERES(Crop Environment Resource Synthesis)-Maize and CROPGRO-Soybean models were calibrated to measured soil moisture and yield data and used to simulate LAI over the growing season. The CERES-Maize model over-predicted LAI at all corn monitoring sites. Simulated LAI from CROPGRO-Soybean was similar to observed and image-estimated LA! for most soybean monitoring sites. These results suggest crop growth model predictions might be improved by incorporating image-estimated LAI. Greater improvements might be expected with com than with soybean.