• The Korean Journal of Ecology
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• 제11권2호
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• pp.83-95
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• 1988

Phytomass, annual net production, respiration, annual gros production and litter fall were estimated in young Korean pine (Pinus koraiensis) plantations reforested 1,2,3,6,9 and 11 years ago, respectivly. The estimated phytomasses in terms of allometry were 0.07, 0.44, 0.58, 13.37, 32.26 and 48.42ton/ha/yr for annual net production and those of understory with harvest method were 3.70, 4.52, 5.28, 6.72, 7.56 and 5.72ton/ha for standing phytomass and 5.01, 4.71, 5.52m 6.15, 4.51 and 2.08 ton/ha/yr for annual net production at 1,2,3,6,9 and 11 year old plantation, respectively. Although the standing phytomass of understory increased gradually until 9 years thereafter decreased, that of white pine increased suddenly from 6 years after reforestation. The ratios of the annyal net production of understory to that of white pine were 71.57, 1.48 and 0.23 at 1,6 and 11 year old plantations, respectively. The net production in calorie value for whole vegetation of the plantations, respectively. The net production in calorie value for whole vegetation of the plantations increased until 9 years thereafter decreased; i.e. 224, 221, 280, 466, 527 and 494X105 kcal/ha/yr at 1,2,3,6,9 and 11 year old plantation, respectivey. The ratio of annual net production to annual gross production of the undersoty was lower than that of the pine at the same plantation age. Efficiency of solat energy untilization for net production by the pine was lower than that by understory y\until six ear old plantation but that was vice versa over 9 year old plantation. That for gross producrion by the pine was lower than that by the unsersotry at all plantations.

• 한국산림과학회지
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• 제89권2호
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• pp.232-240
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• 2000

송이(Tricholoma matsutake, Songyi, matsutake) 생산과 소나무 생장과의 관계를 알기 위하여, 경북 상주지역의 18년(1978-1995)간의 송이 생산량과 인접 속리산의 소나무 연륜생장과 상관관계를 분석하였다. 두 변수간의 상관관계는 r=0.408로써 통계적으로 유의하지 않았다. 상관관계가 낮은 이유로는 송이생산 변동은 버섯발생 및 생장시기인 9월과 10월의 기상에 영향을 받는 데 비하여 소나무 연륜생장 변동은 5월과 6월의 기상에 주로 영향을 받기 때문으로 생각되었다. 1999년의 경우 충북 월악산 국립공원내 송이생산이 절정을 이룬 시기는 10월 초 1주일간으로 이때 일최저기온은 약 $7^{\circ}C-13^{\circ}C$이었다. 이러한 것은 송이생산의 풍-흉년이 단순한 해거리 현상이 아님을 의미한다. 송이증산을 위해서는 자실체 발생기간 중에 발생지의 토양수분과 온도조절이 중요하다고 생각한다.

• 한국태양에너지학회 논문집
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• 제33권6호
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• pp.32-38
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• 2013

In an efforts to encourage renewable energy deployment, the government has initiated so called 1 million green homes program but the accumulated installation capacity of small wind turbine has been about 70kW. It can be explained in several ways such that current subsidy program does not meet public expectations, economic feasibility of wind energy is in doubt or acoustic emission is significant etc. The author investigated annual energy production of Skystream 3.7 wind turbine using measured power curve and wind resource data. The measured power curve of the small wind turbine was obtained through power performance tests at Wol-Ryoung test site. AEP(Annual Energy Production) and CF(Capacity Factor) were evaluated at selected locations with the measured power curve.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.59-71
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• 1986

Net production, dead material increments were measured, and annual respiration loss was simulated through a year to determine the gross production at the Phragmites longivalvis, Carex scabrifolia and Zoysia sinica stand on Okryudeung, a sand bar of the Nagdong river estuary. The maximum live biomass for above-ground organs of the three stands occured in October, i.e., 1, 985, 744 and 1, 013g/m2, and belowground net productions were estimated to be 650, 440 and 412g/m2, respectively. Materials died or shedding from live aboveground organs during the growth season were estimated to be 167, 81 and 0 g/$m^2$. From the results of simulation, annual variation of respiratiion was primarily dependent on the annual variation of temperature through a year. For annual respiration loss in three stands, 21.893, 6.147 and 5.036kg $CO_2/m^2$ were calculated, respectively. Corresponding gross productions were 72, 203, 22, 109 and 19, 909kcal/$m^2$. Respiration of belowground organs corresponded to 65%, 66% and 37% of the total plant respiration, and annual respiration loss accounted for 85%, 78% and 71% of the annual gross production. In view of efficiency of solar energy utilization, 5.8%, 1.8% and 1.6% of incident light energy were converted to gross production of plants during a year. With incident light energy during the growth season from April to September, energy utilizations for net production were estimated to be 1.2%, 0.4% and 0.6% at the three stands.

• Ocean and Polar Research
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• 제44권2호
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• pp.127-137
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• 2022

This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m²/yr, and the highest production was 519 gDWt/m²/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m²/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

• Journal of Ecology and Environment
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• 제44권4호
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• pp.229-240
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• 2020

Background: Genus Quercus is a successful group that has occupied the largest area of forest around the world including South Korea. The acorns are an important food source for both wild animals and humans. Although the reproductive characteristics of this genus are highly variable, it had been rarely studied in South Korea. Therefore, in Seoraksan and Odaesan National Parks (i) we measured the acorn production of Quercus mongolica, an overwhelmingly dominant species in South Korea, for 3 years (2017-2019), (ii) evaluated the spatial-temporal variation of acorn production, and (iii) analyzed the effects of oak- and site-related variables on the acorn production. Results: The annual acorn production of Q. mongolica increased 36 times from 1.2 g m-2 in 2017 to 43.2 g m-2 in 2018, and decreased to 16.7 g m-2 in 2019, resulting in an annual coefficient of variation of 104%. The coefficient of spatial variation was high and reached a maximum of 142%, and the tree size was the greatest influencing factor. That is, with an increase in tree size, acorn production increased significantly (2018 F = 16.3, p < 0.001; 2019 F = 8.2, p < 0.01). Elevation and slope also significantly affected the production in 2019. However, since elevation and tree size showed a positive correlation (r = 0.517, p < 0.001), the increase in acorn production with increasing elevation was possibly due to the effect of tree size. The acorn production of Odaesan for 3 years was 2.2 times greater than that of Seoraksan. This was presumed that there are more distribution of thick oak trees and more favorable site conditions such as deep soil A-layer depth, high organic matter, and slower slopes. Conclusion: As reported for other species of the genus Quercus, the acorn production of Q. mongolica showed large spatial and annual variations. The temporal variability was presumed to be a weather-influenced masting, while the spatial variability was mainly caused by oak tree size.

• 한국해양학회지
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• 제26권3호
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• pp.291-294
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• 1991

이 컴퓨터는 프로그램은 생물량의 변화와 광합성율로부터 해조류의 년 생산량을 계산하기 위해 작성한 것이다. 서로 다른 광도, 온도조건 아래서 측정된 해조류의 단 위무게 당 광합성율을 광도, 수온의 년 변화와 연결시켜 광합성율의 년 변화를 계산하 였다. 이 때 해조류의 광합성율을 1년간 짧은 시간간격으로 측정한다면 좀더 정확한 값을 얻을 수 있을 것이다. 광합성율의 시간에 따른 변화를 생물량의 시간에 따른 변 화와 연결시켜 년 총생산량을 계산하였다. 어느 주어진 시간에서의 생물량을 알고 이 때의 단위무게당 광합성율을 알면 이들 값을 곱하여 이 시간에서의 총 생산량을 알 수 있기 때문이었다. 프로그램은 개인용을 이용하는데 편리하도록 파스칼 언어를 사용하 였으며, 계산결과를 데이터 베이스에 옮길 수 있도록 하여 다양한 프린터 사양을 가지게 한 것도 하나의 특징이다. 강원도 고성군 오호리에 서식하는 알쏭이 모자반을 대상으로 측정한 생물량, 광합성율의 값들을 이 프로그램에서 예로 사용하였다.

• 전기학회논문지
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• 제56권12호
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• pp.2109-2115
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• 2007

The wind generators have been installed with high output power to increase the energy production and efficiency. Hence, Optimal design of the direct-driven PM wind generator, coupled with F.E.M(Finite Element Method) and Genetic Algorithm(GA), has been performed to maximize the Annual Energy Production(AEP) over the whole wind speed characterized by the statistical model of wind speed distribution. Particularly, the parallel computing via internet web service has been applied to loose excessive computing times for optimization. The results of the optimal design of Surface-Mounted Permanent Magnet Synchronous Generator(SPMSG) are compared with each other candidates to verify the usefulness of the maximizing AEP model.

• 한국가금학회지
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• 제9권1호
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• pp.35-42
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• 1982

본 연구는 산업계의 산란능력을 개량하는데 있어서 부분검정의 효율성을 구명하기 위하여 White Leghorn 합성종계통 선발 1세대의 478수에서 측정된 산란기록을 분석자료로 이용하였다. 조사된 형질은 초산일령, 40주령까지의 산란수(P) 및 산란율(P'). 41주령에서 64주령까지의 산란수(R) 및 산란율(R'), 그리고 전체산란수(A) 및 산란율(A') 이었으며, 초산일령부터 40주령까지의 단기검정성적을 다시 세분하여 초산일령에서 22주, 24주, ㆍㆍㆍㆍ, 40주까지 2주씩 더해 나간 기간동안의 산란수(E$_{t}$) 및 산란율(E'$_{t}$), 그 반대로 40주령까지의 성적을 최초의 초산일령 19주령 부터, 2주씩 제외시키고 얻은 나머지 기간의 산란수(S$_{t}$) 및 산란율(S'$_{t}$)을 각각 구하여 상대적 효율을 비교하였다.을 비교하였다.

• 한국패류학회지
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• 제20권1호
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• pp.45-53
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• 2004

This study have conducted to calibrate the productivities on the mussel (Mytilus galloprovincialis) cultures in Jinhae Bay. Annual water temperature, salinity and dissolved oxygen have varied to 7.2-$25.9^{\circ}C$, 32.9-34.0 psu, 7.9-8.7 mg/l, respectively. In April, the smallest size of spat, 3.3 mm in shell length, have recruited, and 82.5 mm have recorded to the maximum. In summer, variations of growing up between individuals showed both shell length and weights at same cohort. Annual production at 2 m, 5 m, 8 m depth calculated to 10.91, 10.85 and 9.19 gWWt/ind./yr, respectively. Mussel cultivated in the upper part of the water column (two meter depth) were significantly longer and heavier than those in lower part (eight meter depth). After the recruitment, monthly production showed gradual increment at all positions during summer. As results, annual production of mussel cultivated seemed to be controlled by conditions of growing up in summer. Based on the productivities calculated to this study, the total annual production of the mussel cultivated in Jinhae Bay have estimated about 196 ton/ha/yr.