• Ocean and Polar Research
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• 제25권4호
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• pp.653-662
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• 2003

Changes in the area of geo-ecosystem $(62^{\circ}09'S,\;58^{\circ}31'w)$ reflect climatic changes in the South Shetland Islands. Air temperature and deglaciation will increase. The ice-free space area at the SSSS 8- (ASPA 121) site has enlarged threefold during the last 21 years, thus creating conditions for inhabitation and succession. Wind, water and snow play important roles in transportation of geochemical components. They distribute nutrients, mineral substances, seeds, fragments of plants and animals, etc. Plant and animal colonization is patchy and it happens at random in an 'island' - like manner. The colonization pattern is dependant, to a high degree on physical factors. The newly uncovered ice-free areas are at first inhabited by a vascular plant known as the Deschampsia antarctica. The border of the land-oasis with Admiralty Bay is the place where the processes related to animal feeding at the sea and reproduction on the land take place. Bird colonies and pinniped lairs form centers of fertilization surrounded by high chemical gradients dependent on the direction of the flow of nutrients $(e.g.\;NH_4)$. During the last 25 years, the numbers of penguins in this region have decreased, and thus the amount of materials excreted on land has diminished. The numbers of fur seals change in multi-annual cycles, and their migration into this area is related to the E1 $Ni\~{n}o$ phenomenon. The numbers of elephant seals in the area did not change. Organic matter deposited by the sea onto the shore are a source of nutrients and deficient chemical elements on land. Mineral matter is washed out into the waters of Admiralty Bay. These processes change seasonally, and multi annually. Negative effects on the environment at Arctowski Station induced by man are slight, but noticeable nevertheless. Physical processes have the largest influence on the living conditions and distribution of plants and animals, and as a consequence, on the functioning of the geo-ecosystem in the coastal-shore zone of the Maritime Antarctic.

• Asian-Australasian Journal of Animal Sciences
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• 제9권2호
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• pp.203-210
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• 1996

A 13-month study was conducted to determine the monthly variation of crude protein(CP), cell contents(CC), fiber fractions and mineral concentrations of paragrass [Brachiaria mutica (Forsk.) Stapf.] and stargrass (Cynodon plectostachyum Pilger) and to estimate the correlations among the nutrient fractions and climatic factors. The forage samples collected by hand plucking were found to contain CP and mineral concentrations. i.e. calcium(Ca), magnesium(Mg), potassium(K) and zinc(Zn) above the critical levels based on ruminant veeds. Monthly differences(p<0.05) were observed in all CP, CC, neutral detergent fiber(NDF), acid detergent fiber(ADF), hemicellulose(HE), cellulose(CE) and acid detergent lignin(ADL) between the two grass species. Monthly differences(p<0.05) were also observed in all concentrations of forage Ca, K, phosphorus(P), copper(Cu) and Zn except in Mg of both grasses and K of stargrass. Species differences(p<0.05) were observed in all nutrient fractions except Mg and K concentrations. Rainfall had positive correlations to CP, P(p<0.01) and CC(p<0.05); it had negative correlations to NDF(p<0.05). ADF, CE, Ca, Cu and Zn(p<0.01). Temperature, humidity and daylength had also some correlations to various nutrient fractions.

• 자원ㆍ환경경제연구
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• 제25권2호
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• pp.277-297
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• 2016

본 연구는 기후변수들의 변동 특성이 한국 제조업의 총요소생산성에 미치는 영향을 분석하였다. 대표적인 기후변수인 기온, 강수량, 습도는 노동효율성에 부정적인 영향을 미칠 것으로 예상되므로 기온, 강수량, 습도의 변동특성이 한국 광역자치단체 제조업 총생산성에 미치는 영향을 분석하였다. 본 연구는 최근 기후변화로 기후 변동성이 높아지는 현상을 고려하기 위해 기후변수들의 평균값뿐만 아니라 최고값을 고려하여 분석하였다. 선형회귀분석 결과 선행연구 결과와 달리 기온과 습도가 제조업 생산성에 유의미한 영향을 미치지 않았다. 강수량의 평균적 증가는 부정적 영향을 미치는 것으로 분석되었다. 패널자료를 분석한 결과에서는 기온, 강수량 모두 제조업 총생산에 유의미한 영향을 주지 않는 것으로 나타났다. 반면 평균 습도의 상승은 제조업 총생산을 증가시키는 것으로 나타났다. 실내 작업이 많은 제조업의 경우 기후자체의 변화보다도 기업체들의 적응능력이 생산성 변화와 직접적인 관련이 있다. 한국 제조업의 경우 기온이나 습도의 변화가 급격하게 이루어지지 않고 있고, 냉난방 시스템 구축 등을 통해 기후변화에 잘 적응하고 있는 것으로 분석된다.

• 한국농공학회논문집
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• 제52권3호
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• pp.39-45
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• 2010

Quantification of carbon absorption and understanding the human induced land use changes (LUC) forms one of the major study with respect to global climatic changes. An attempt study has been made to quantify the carbon absorption by LUC through remote sensing technology. The Landsat imagery four time periods was classified with the hybrid classification method in order to quantify carbon absorption by LUC. Thereafter, for estimating the amount of carbon absorption, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated with the crown width extracted from digital forest cover type map. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the IPCC guideline, was used to convert the stand biomass into the amount of carbon absorption. Total carbon absorption has been modeled by taking areal estimates of LUC of four time periods and carbon factors for land use type and standing biomass. Results of this study, through LUC suggests that over a period of construction, 7.10 % of forest and 9.43 % of barren were converted into urban. In the conversion process, there has been a loss of 6.66 t/ha/y (7.94 %) of carbon absorption from the study area.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.263-269
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• 1996

In indian agricultural , the energy use pattern has played dominant role in influencing the level of mechanization . Besides that the agro-climatic factors as well as the size of holdings do affect the degree of mechanization . Nearly 30 percent of total cultivated area is owned by l76 percent of the small and tiny land holders each owning even less than a hectare. On the other hand, about 2 percent of land owners cultivate land. These variabilitieshave greatly influenced the ownership of power sources on Indian farms. Small farmers, employ human and animal energies with the use of hand tools and animal drawn equipments. Whereases, the use of tractors, power tillers, electric motors, etc. on small farms is on a marginal scale. There are few pockets and also extensive wheat growing regions where mechanical and electrical power sources are extensively used in production agriculture leading to about 185% of cropping intensity . In that region, the animal energy is employed for on the farm transport of fertilizers, fodders and fuel to support milch animals and other household activities . Inspite of high degree of mechanization, the harvesting of crops is done by human labour with few exceptions of harvesting wheat crops by combines in few pockets. In overall assessment of mechanization, the following conclusions are drawn : ⅰ) Farm operation which show a growing trend of mechanization are (a) tillge, (b) seedling (c) Irrigation (d) Plant protection application (e) Threshing and (f) Transport . ⅱ) Crop cultivation system in respect of wheat, maize and sorghum have been greatly mechanized. ⅲ) The least mechanized cropping systems are (a) vegetable production and (b) cultivation of sugarcane, cotton, rice and pulses. ⅳ) Annual production of tractor has touched the figure of 280.000 by 1995 and the total number has crossed 1.5million on Indian farms.

• The Plant Pathology Journal
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• 제28권2호
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• pp.123-136
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• 2012

Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tropical and sub-tropical agro-ecosystems worldwide. In recent years, they have also introduced in temperate regions of the world where they have great impact and are posing a serious threat to a variety of greenhouse crops. Begomoviral diseases can in extreme cases reduce yields to zero leading to catastrophic losses in agriculture. They are still evolving and pose a serious threat to sustainable agriculture across the world, particularly in tropics and sub-tropics. Till recently, there have been no records on the occurrence of begomoviral disease in South Korea, however, the etiology of other plant viral diseases are known since last century. The first begomovirus infected sample was collected from sweet potato plant in 2003 and since then there has been gradual increase in the begomoviral epidemics specially in tomato and sweet potato crops. So far, 48 begomovirus sequences originating from various plant species have been submitted in public sequence data base from different parts of the country. The rapid emergence of begomoviral epidemics might be with some of the factors like evolution of new variants of the viruses, appearance of efficient vectors, changing cropping systems, introduction of susceptible plant varieties, increase in global trade in agricultural products, intercontinental transportation networks, and changes in global climatic conditions. Another concern might be the emergence of a begomovirus complex and satellite DNA molecules. Thorough understanding of the pathosystems is needed for the designing of effective managements. Efforts should also be made towards the integration of the resistant genes for the development of transgenic plants specially tomato and sweet potato as they have been found to be widely infected in South Korea. There should be efficient surveillance for emergence or incursions of other begomoviruses and biotypes of whitefly. This review discusses the general characteristics of begomoviruses, transmission by their vector B. tabaci with an especial emphasis on the occurrence and distribution of begomoviruses in South Korea, and control measures that must be addressed in order to develop more sustainable management strategies.

• 한국작물학회지
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• 제50권1호
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• pp.32-38
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• 2005

A long-term study initiated in 1989 at San-born Field, Columbia, Missouri, was designed to evaluate the affect of environmental factors, nitrogen application, and crop rotation on soybean (Glycine max [L.] Merr.) seed composition. Soybeans were grown as part of a four- year rotation which included corn (Zea maize L.), wheat (Triticum aestivum L.), and red clover (Trifolium pratense L.). Results from soil tests made prior to initiation of the study and subsequently every five years, were used to calculate application rates of nitrogen, phosphorus, and potassium necessary for target yield of pursuant crops. In the experimental design, nitrogen was applied to one-half of the plot on which the non-leguminous crop, either corn or wheat was grown. Analysis of soybean seed by near infrared reflectance spectroscopy collected over an 11-year period revealed a linear increase in protein and decrease in oil content. Application of nitrogen fertilizer to non-leguminous crops did not have an apparent effect on total protein or oil content of subsequent soybean crop. Analysis of soybean seed proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis in conjunction with computer­assisted densitometry revealed subtle changes in the accumulation of seed proteins. Immunoblot analysis using antibodies raised against the $\beta-subunit$ of $\beta-conglycinin$ showed a gradual increase in the accumulation of the 7S components during successive years of the experiment. A linear increase in temperature and decrease in rainfall was observed from the onset of data· collection. Higher temperatures during the growing season have been linked to increased protein and diminished oil content of soybean, thus changes observed in this study are possibly related to climatic conditions. However, crop rotation and subsequent changes in soil ecology may contribute to these observed changes in the seed composition.

• 한국건설관리학회논문집
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• 제6권1호
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• pp.58-64
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• 2005

공사기간은 순수한 작업기간에 작업불가능기간을 더하여 산정할 수 있다. 순작업기간은 과거의 실적자료로부터 구할 수 있다. 작업불가능기간도 기상자료로부터 정확하게 산정할 수 있지만, 이에 대한 연구가 부족한 실정이다. 본 연구의 목적은 작업불가능기간에 영향을 미치는 요소 중 기후요소를 분석하여 인천지역의 작업불가능일수를 산정 $\cdot$ 제시하는 것이다. 기존의 연구문헌을 검토하고, 최근 30년간의 기후자료를 통계분석 하여 인천지역의 작업불가능일수를 제안하였다. 강우량의 경우 10mm이상일 때 작업이 불가능하며 그 일수는 연 29일로 나타났다. 저온으로 인한 골조부문($4^{\circ}C$이하)과 마감 부문($0^{\circ}C$이하)의 작업불가능일수는 각각 97일, 52일이며, 고온으로 인한 작업불가능일수는 일최고기온 $32^{\circ}C$이상을 기준으로 할 때 3일로 산출되었다.

• 한국수산과학회지
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• 제30권6호
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• pp.974-983
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• 1997

The Okhotsk Sea is unique natural object with climatic peculiarities. The climate of the Okhotsk Sea results from the general distribution of solar radiation during a year, and the characteristics of the atmospheric circulation that varies through a year: In cold half year the main pressure formations are Siberian high and Aleutian low. Asian low centered on Afghanistan dominates over the Asian continent in summer. The North-Pacific sea surface is under effect of permanent North Pacific high. The changes in their position from year to year are very significant. The anticyclonic activity over the Far Eastern Seas is one of the main factors for the formation of weather anomalies over the adjacent territories. The analysis of summer weather characteristics over the coast of Okhotsk and East Sea using the data obtained from Hydrometeorological stations during $1949\~1990$ showed that, to a great extent, distribution of the air temperature depends on thermal state of the Okhotsk Sea and atmospheric circulation over it. We show some relations between weather characteristics and the intensity of atmospheric action center for the North Pacific high in summer when its ridge propagates to Okhotsk Sea. Correlation coefficients between air pressure over the Okhotsk Sea and air temperature for the coastal areas reach up to 0.7. Analysis of the spatial-temporal distribution of main meteorological values over the Okhotsk Sea such as air pressure, and air temperature are also performed.

• 한국농공학회지
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• 제44권7호
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• pp.64-73
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• 2002

This study was performed to evaluate effects of physical characteristics of both watershed and reservoir on nutrient-chlorophyll relationship in Korean reservoirs. Simple linear models were developed with published data in Korea including 415 reservoirs and 11 multi-purpose dams, and physico-chemical parameters of reservoirs and characteristics relationship of models were analyzed. Theoretical residence time in Korean reservoirs was strongly correlated with the ratio of TA/ST (drainage area + surface area / storage volume) in the logarithmic function. As a result of monthly nutrients-chlorophyll-a regression analysis, significant Chl-a-TP relationship appeared during May～July. The high Chl-a yields per total phosphorus appeared during this time (R$\^$2/=0.51, p<0.001, N= 1088). Chlorophyll-a demonstrated much stronger relationship with TP. than TN. Seasonal algal-nutrient coupling were closely related with N:P ratio in the reservoir water, and it was, in turn, dependent on the monsoon climatic condition (precipitation). Based on the results of regression analysis and high N:P ratio, a major limiting factor of algal growth appeared to be phosphorus during this time. Unlikely TA/ST ratio, DA/SA ratio (drainage area f surface area) was likely to influence directly on the nutrient-Chl-a relationship, indicating that if storage volume and inflowing water volume were the same, algal biomass could be developed more in reservoirs with large surface area. Thus, DA/SA ratio seemed to be an important factor to affect the development of algal biomass in Korean reservoirs. With low determination coefficient of TP-Chl-a relationship, our findings indicated not only nutrient (phosphorus) but also other physical factors, such as DA/SA ratio, may affect algal biomass development in Korean reservoirs, where actual residence time appears to be more closely related to reservoir surface area rather than storage volume.