• Title/Summary/Keyword: Climatic

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Seedling Emergence and Mesocotyl Elongation as affected by Temperature and Seeding Depth in Direct-seeded Rice on Dry Soil (벼 건답직파재배에서 온도 및 파종심도가 종자의 출아와 중배축 신장에 미치는 영향)

  • Lee, Chul-Won;Yun, Yong-Dae;Oh, Yun-Jin;Cho, Sang-Yeol
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.37 no.6
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    • pp.534-540
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    • 1992
  • Climatic condition and seeding depth affect the seedling stand and early growth in the direct-seeded rice cultivation on dry soil. This experiment was conducted to elucidate the effects of the day /night temperatures and the seeding depths on the seedling emergence and mesocotyl elongation of rice seed. Three combinations of the day/night temperatures(25/2$0^{\circ}C$ 20/15$^{\circ}C$ and 20/1$0^{\circ}C$) were employed with seeding depths 1, 3, 5 and 7cm at the Phytotron of the Crop Experiment Station in 1991. It appeared that seedling emergence ratio increased and days to seedling emergence decreased in the high temperature (25/2$0^{\circ}C$) and the deep seeding depth (5 and 7cm) condition. The seedling emergence ratio did not. show the, difference up . to the seeding depths of 3cm and below, but the ratio decreased from the seeding depths of 5cm and above. Plant height and leaf number were almost the same up to the depths of 3cm at 30 days after seeding, but those of the seeding depths of 5cm and 7cm were remarkably reduced in all temperature combinations. Mesocotyl and lower internode elongation were seen in the high temperature(25/2$0^{\circ}C$) with the seeding depths of 5cm and 7cm. In the seeding depth of 6cm, of the tested varieties, Tamjinbyeo and Odaebyeo showed the highest emergence ratio. Generally, leaves of all tested varieties appeared approximately in the soil depth of 3cm, so the reasonable seeding depth will be around 3cm in the direct-seeded cultivation on dry soil.

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Current Status and Perspectives of Quality Improvement in Sesame (참깨 품질 연구의 현황과 문제점 및 전망)

  • Lee, Bong-Ho;Lee, Jung-Il;Park, Rae-Kyeong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.33 no.s01
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    • pp.86-97
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    • 1988
  • Sesame(Sesamum indicum L.) is probably the most ancient oilseed crop known in the world. The seed of sesame is used in a variety of ways as food. The whole seed may be eaten raw, either roasted or parched, or fed to birds and stock. Sesame oil is used as a salad or cooking oil, in shortening, margarine and in the manufacture of soap. Minor uses are as a fixative in the perfume industry and formerly as a carrier for fatsoluble substances in pharmaceuticals such as penicillin. One of the minor constituents of sesame oil, sesamin, is used for its synergistic effect in pyrethrin insecticides, in addition of a small quantity of this substance markedly increases the effectiveness of fly sprays. The meal remaining after oil extraction can be used as and animal feed-stuff or as manure. In general sesame meal is considered to be equal to cottonseed or soybean meal as a protein supplement for livestock and poultry. It is especially high in certain amino-acids such as methionine, which is low in soybean meal, and thus can be combined with it or similar meal to form a more balanced ration. An attempt to summarize the literature review on quality improvement of sesame was made to discuss the accomplishments of the past and perspectives in the future. The reviews on quality improvement of sesame were mainly discussed in connection with the cultural practices and genetic informations in current status. The emphasis focussed on environmental variation of quality in cultural practices, such as harvest time, variety by location, climatic condition, fertilizer application, and growth regulator treatment. On the genetic variation of quality, it was discussed on variety background, mutation breeding, correlations, and inheritance of quality related characteristics. It also was discussed on relationship between quality and plant traits, storage condition or period, and seed coat color. Moreover, current research status were reviewed on some minor elements such as sesamin, oxalic acid, and trypsin inhibitor. As a results of the review, the lack of an effort to quality improvement in each utilization area was indicated as a problem area. More active efforts for the improvement of quality were also insufficient to incorporate the available genes for quality in breeding method or collection and analysis of breeding materials. Therefore, researches in the future would be recommended to emphasize on these problem areas.

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Native Hawaiian Collection Systems in Lava Tubes(Caves) and Fault Cracks: Puna - Ka'u Districts, Hawaii

  • Martin, James F.
    • Journal of the speleological society of Korea
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    • no.4
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    • pp.41-50
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    • 1996
  • The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

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Studies on the Controlled Release Fertilizer METAP Application on Paddy Rice (1972) (수도에 대한 완효성비료 METAP의 비효시험(1972))

  • Lee, E.W.;Ahn, S.B.;Lee, M.H.;Lee, Z.Y.;Song, N.H.;Kwon, S.M.;Kim, C.Y.;Choe, B.C.;Chung, H.S.;Cho, B.O.;Lee, I.J.;Park, C.S.;Ko, C.S.;Park, K.H.;Chung, S.C.;Chung, H.S.;Lee, H.D.;Park, S.T.;Lee, H.S.;Choe, S.R.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.13
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    • pp.107-118
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    • 1973
  • Experiments were carried out to study the effectiveness of METAP as a slow released fertilizer on the growth, grain yield and its components of paddy rice, and to compare its effects with those of single fertilizers in the fields of 3 Crop Experiment Stations and 7 provincial Offices of Rural Development. The effectiveness of METAP seems to be different according to the physical and chemical characteristics of soil, the time of application, climatic conditions, variety and cultural methods. Therefore, the experimental results obtained from the above experiment are summurized as follows: 1. When METAP was applied into sandy soil, grain yield was increased due to increase of the number of panicles, and split application of METAP was more effective than basal only. However, in the reclaimed soil, not heavily percolated soil and fertile soil, no differences were observed between MET AP and single fertilizer applied plot. 2. When a rice variety, 'TONGIL' which is sensitive to the low temperature and produce higher yield in the early transplanting, was not transplanted early and air temperature is relatively lower during the ripening stage, the percentage of ripened grains and 1,000 grains weight were not higher in the METAP applied plots than in the single fertilizer applied plots.

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Breeding of Sesame (Sesamum indicum L.) for Oil Quality Improvement II. FattyAcid Composition of Sesame Seeds under Different Climatic Conditions and Locations (참깨 품종개량에 관한 연구 제2보 지역차이 및 기상환경에 따른 참깨 지방산변화)

  • Lee, J.I.;Lee, S.T.;Oh, S.K.;Kang, C.W.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.1
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    • pp.90-95
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    • 1981
  • This study was conducted to ascertain the seed quality of sesame (Sesamum indicum L.) under different environmental conditions. The results were summarized as follows; 1. The sesame seeds harvested in the central noethern area of Korea showed higher linoleic acid content than did those in the southern area. 2. The linoleic acid content was highly negatively correlated with the accumulated temperature during maturity (r=-.595) and the correlation coefficient between Linoleic acid content and the accumulated solar radiation during maturity was highly significant (r=.613). Thus, the relative low temperature and high solar radiation during the maturity would be importnat factors for the increase in the linoleic acid content of sesame seeds. 3. The oleic acid content was higher in the southern area than in the central northern area. 4. The oleic acid content was highly correlated with the accumulated temperature (r=.644) and the accumulated solar radiation (r=-.456), respectively. 5. The linoleic and oleic acid are important components of sesame seeds, and these show a relative relationship to determine the oil content of the seeds. 6. The oil quality in the central northern area was superior to that in the southern area.

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A Multi-Criteria Spatial Decision Support System for Smart Hydrogen Energy Plant Location Planning in the Gangwon-Do Region, South Korea (강원도 지역 스마트 수소에너지 플랜트 입지계획을 위한 다기준 공간의사결정 지원 시스템 연구)

  • Yum, Sang-Guk;Adhikari, Manik Das
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.3
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    • pp.381-395
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    • 2023
  • This paper presents a GIS-based site suitability analysis for a smart hydrogen energy plant in the Gangwon-Do region, South Korea. A GIS-based multi-criteria decision analysis (MCDA) was implemented in this study to identify the most suitable sites for the development of smart hydrogen energy plants. The study utilizes various spatial data layers, including hydrogen generation potential and climatic conditions, environmental and topographic conditions, and natural catastrophic conditions, to evaluate the suitability of potential sites for the hydrogen energy plant. The spatial data layers were then used to rank and prioritize the sites based on suitability. The findings revealed that 4.26% of the study area, or 712.14 km2, was suitable for constructing smart hydrogen energy plants. Some regions of Cheorwon-gun, Chuncheon-si, Wonju-si, Yanggu-gun, Gangneung-si, Hoengseong-gun, and near the coastal region along the east coast were found to be suitable for solar and wind energy utilization. The proposed MCDA provides a valuable tool for decision-makers and stakeholders to make informed decisions on the location of smart hydrogen energy plants and supports the transition to a sustainable and low-carbon energy system. Decision-makers can use the results of this study to select suitable sites for constructing smart hydrogen energy plants.

Yield Comparison Simulation between Seasonal Climatic Scenarios for Italian Ryegrass (Lolium Multiflorum Lam.) in Southern Coastal Regions of Korea (우리나라 남부해안지역에서 이탈리안 라이그라스에 대한 계절적 기후시나리오 간 수량비교 시뮬레이션)

  • Kim, Moonju;Sung, Kyung Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.42 no.1
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    • pp.1-9
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    • 2022
  • This study was carried out to compare the DMY (dry matter yield) of IRG (Italian ryegrass) in the southern coastal regions of Korea due to seasonal climate scenarios such as the Kaul-Changma (late monsoon) in autumn, extreme winter cold, and drought in the next spring. The IRG data (n = 203) were collected from various Reports for Collaborative Research Program to Develop New Cultivars of Summer Crops in Jeju, 203 Namwon, and Yeungam from the Rural Development Administration - (en DASH). In order to define the seasonal climate scenarios, climate variables including temperature, humidity, wind, sunshine were used by collected from the Korean Meteorological Administration. The discriminant analysis based on 5% significance level was performed to distinguish normal and abnormal climate scenarios. Furthermore, the DMY comparison was simulated based on the information of sample distribution of IRG. As a result, in the southern coastal regions, only the impact of next spring drought on DMY of IRG was critical. Although the severe winter cold was clearly classified from the normal, there was no difference in DMY. Thus, the DMY comparison was simulated only for the next spring drought. Under the yield comparison simulation, DMY (kg/ha) in the normal and drought was 14,743.83 and 12,707.97 respectively. It implies that the expected damage caused by the spring drought was about 2,000 kg/ha. Furthermore, the predicted DMY of spring drought was wider and slower than that of normal, indicating on high variability. This study is meaningful in confirming the predictive DMY damage and its possibility by spring drought for IRG via statistical simulation considering seasonal climate scenarios.

Evaluation of Habitat Suitability of Honey Tree Species, Kalopanax septemlobus Koidz., Tilia amurensis Rupr. and Styrax obassis Siebold & Z ucc. in the Baekdudaegan Mountains using MaxEnt Model (MaxEnt 모형을 활용한 백두대간에 자생하는 주요 밀원수종인 음나무, 피나무, 쪽동백나무의 서식지 적합성 평가)

  • Sim, Hyung Seok;Lee, Min-Ki;Lee, Chang-Bae
    • Journal of Korean Society of Forest Science
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    • v.111 no.1
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    • pp.50-60
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    • 2022
  • In this study, habitat suitability was analyzed for three major honey tree species, namely Kalopanax septemlobus, Tilia amurensis, and Styrax obassis, in the Baekdudaegan Mountains using MaxEnt models. The AUC values indicating the prediction accuracies of the models were 0.747, 0.790, and 0.755 for K. septemlobus, T. amurensis, and S. obassis, respectively. The most important variables for K. septemlobus and T. amurensis were elevation, mean annual temperature, and slope, whereas mean annual temperature, elevation, and mean annual precipitation were the most important predictors for S. obassis. For all three studied species, elevation and mean annual temperature were the most important topographic and climatic factors, respectively, indicating that such variables are crucial for explaining species distribution. Honey tree species are essential resources in forest beekeeping, a high value-added process for improving forest income, and this study identified sites with the potential for management of such species in the Baekdudaegan Mountains, where it may be possible to establish a honey forest. However, the accuracy of the models should be improved through comprehensive analysis with abiotic variables, such as soil properties and aridity, which affect the distribution of honey tree species, as well as biotic variables, such as interspecific competition.

Cultivation of millet in Mahan-Baekje Villages: Archaeobotanical examination of Osan site, Jangheung, Korea (전남 마한백제계 취락의 서속(黍粟) 재배와 농경 체계: 장흥 봉림리 오산유적 자료를 중심으로)

  • RYU Ara;KIM Sebin;OH Byungwook;KIM Minkoo
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.48-60
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    • 2023
  • Although foxtail and broomcorn millet have been cultivated since the Neolithic Age on the Korean Peninsula, there have been few studies on how the importance of millet cultivation changed over time. The discovery of millet has been rare in the Mahan-Baekje villages in the Jeonnam region, and archaeological discussions on ancient farming have centered around rice farming. However, a large amount of millet was found at the Osan site in Bongrim-ri, Jangheung, showing that the tradition of millet cultivation continued during the AD 3-4 centuries. In contrast to rice farming, which requires low-lying wetlands, hot and humid summers, and a large labor force, millet cultivation has few restrictions in terms of growing environment and labor mobilization. Regarding harvesting seasons, the crops at the Osan site can be divided into fall harvesting (rice, legumes, millet) and summer harvesting (wheat). Regarding field locations, the crops are divided into wetland crops (rice) and dryland crops (wheat, legumes, millet). The operation of the dual agricultural system contributed to subsistence resilience and agricultural production, making it possible to effectively manage social and climatic crises.

Karst Studies in the Korean Geographical Society: Achievements for the Past Fifty Years (한국 지리학계의 카르스트 연구)

  • PARK, Sunyurp
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.4
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    • pp.127-140
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    • 2011
  • Research achievement of Korean geographers on karst studies was evaluated based on the number of publications for the past fifty years, which were divided into four main periods, including beginning, youth, growth, and maturity stages. The descriptive statistics of research papers published in major geography journals were computed and these articles were classified according to their main subjects and study areas. The role of moisture is particularly important in Karst geomorphology compared to the other geomorphological fields. The morphology, landscape, and formation processes of tropical and temperate karst are different from each other, and the regional and altitudinal characteristics of karst environments are significantly diverse. Thus, it is likely that the detailed records of climatic changes are preserved in the northeast Asian karst landform. Since karst geomorphology can be a major cause of natural hazards, such as collapsed surfaces or subsidence, which are associated with anthropogenic activities, including underground-water pumping and land use, education and training of physical geographers, specializing on monsoon effects, distributions of limestone, and soil characteristics, are critical issues to foster the capacity of disaster management in the nation. Moreover, knowing that the unique and spectacular landscape of karst geomorphology is a valuable, natural resource of tourism and has aesthetic values on its own, contributions of geographers to the introduction, conservation, research, and development of karst environment should be emphasized.