• 한국농림기상학회지
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• 제20권1호
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• pp.73-87
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• 2018

여름철 도시의 친환경적 기온 저감 방안으로 고려되는 산림에 의한 기온 저감 효과를 정량화 하기 위해 광릉 침 활엽수림과 인근 포천시의 도시 지역과의 기온차를 기온, 바람, 일사, 잠열 등의 미기상 인자를 이용하여 분석하였다. 2016년과 2017년의 6, 7, 8월 3개월 동안 산림 상 하부와 산림과 도심 지역의 평균 최대 기온차는 각각 $-1.9^{\circ}C$, $-3.4^{\circ}C$로 17시경에 나타났으며, 침 활엽수림 간의 차이는 없었다. 산림에 의한 기온 저감 효과는 14시부터 17시까지 누적된 증발산량, 일사량과 양의 상관관계를 나타냈으며, 풍속과는 음의 상관관계를 나타냈다. 이를 이용해 산림의 기온저감 효과를 정량화하는 모델을 개발하였다. 산림에 의한 야간 기온 저감 효과는 복사냉각으로 인한 찬공기의 생성과 생성된 찬공기가 산지의 하류로 이동하면서 발생하는 기온역전 현상에 의한 것으로 나타났다. 본 연구 결과를 서울시내 28개 AWS를 이용해 검증해 본 결과, 서울시 각 지역 주간의 기온은 식생의 증발산에 영향을 미치는 AWS 주변 식생 면적 및 규모와의 음의 상관관계를, 그리고 야간의 기온은 주변 식생 규모 및 인근 산림의 높이와 유의한 음의 상관관계를 재확인할 수 있었다. 따라서 도시림의 조성과 관리 및 산으로부터 바람길의 조성이 도시 온도 저감에 중요함을 알 수 있다.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2019년도 하계 학술발표초록집
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• pp.216-217
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• 2019

• 한국자원식물학회지
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• 제11권2호
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• pp.119-123
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• 1998

Effects of elevated CO2 and temperature on nitrogen (N) uptake , leaf N concentration, N partitioning , N use efficiency (NUE) and grain yield of pot and field grown rice (Oryza sativa. L.cv. Chukwangbyeo) under canopy-like conditions were studied over three years. Rice plants were grown in pots and in the field in temperature gradient chambers containing either ambient(350ppm) or elevated CO2 concentrations (690 or 650ppm) in conbination with either four or seven temperature regimes ranging form ambient temperature(AT) to AT plus 3$^{\circ}C$. There were three N supplies 94g or 6g m-2 to 20g or 48g m-2.Elevated CO2 increased N uptake in field-grown rice ; the magnitude of this effect was thelargest (+15%) at the highest N level. However, in pot-grown rice, N uptake was suppressed with the effect was the largest at high N levels. Leaf N concentration declined at elevated CO2 mainly due to a decrease in N partitiioning to the leaf blades. Air temperature had little effect on the N parameters mentioned previously, wherease NUE for spikelet production declined rapidly with increased temperature irrespective of CO2 concentration. The response of the biomass to elevated CO2 varied with N level, with the greatest response at 20g N m-2 (+30%) . At AT, where high temperature-induced sterility was generally not observed, elevated CO2 increased yield. However, the magnitude of this effect varied greatly (2-39%) with N level, and was mainly dependent on the magnitude of the increase in spikelet number.

• 한국응용곤충학회지
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• 제42권3호
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• pp.233-240
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• 2003

항온$.$항습 조건에서 Amblyseius fallacis의 접종밀도별 귤응애에 대한 밀도억제효과를 조사한 결과, 16 : 1(Panonychus citri :A.fallacis) 이상의 비율로 접종한 경우에 귤응애의 밀도가 매우 효과적으로 억제되었다. 그리고 귤응애의 초기 밀도가 잎 당 0.5마리와 1마리일 때 20:1로 1-2회씩 방사한 결과, 모든 처리에서 A.fallacis의 밀도는 다소 높게 형성되었으나 귤응애에 대한 뚜렷한 억제효과를 보이지는 않았다. 정상적으로 관리되고 있는 비닐하우스의 감귤나무에서 귤응애가 잎 당 0.1-0.2마리 정도일 때 10:1로 2회 방사한 경우에는 A.fallacis의 밀도도 높게 형성되었으며, 유기합성농약을 살포한 처리구와 동일할 정도의 높은 방제효과를 보였다. 그리고 이리응애가 서식하는 곳은 수관 내부이므로 수관 내부와 외부의 환경차이를 조사한 결과,주간에는 수관내부가 외부에 비해 기온은 낮고, 상대습도는 높기 때문에 A.fallacis의 서식에 다소 유리한 것으로 나타났으며, 기온은 7.2$^{\circ}C$ 이상, 상대습도는 18.5% 이상까지도 차이가 있었다.

• 한국토양비료학회지
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• 제21권1호
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• pp.11-14
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• 1988

옥수수 군락상(群落上)에서 측정(測定)한 순복사량(純輻射量)과 일사량(日射量), 온도(氣溫)의 관측치(觀測値)를 이용(利用)하여 일사량(日射量)과 순복사량(純輻射量)의 관계식을 구하고 복사수지식(輻射收支式)의 각항(各項)에 관(關)한 경험식(經驗式)을 이용(利用)하여 주간순복사량(晝間純輻射量)으르 추정(推定)하는 모델을 제안(題案)하였으며 결과(結果)를 요약(要約)하면 다음과 같다. 1. 일사량(日射量)과 주간순복사량(晝間純輻射量)의 관계식(關係式)은 $R_n(+)=0.6659$ $R_s$로 일사량(日射量)과 주간복사량(晝間純輻射量)의 비율(比率)이 66%이상(以上)이었다. 2. 일조율(日照率)이 35%이상(以上)인 흐린날의 일사량(日射量)과 주간순복사량(晝間純輻射量)의 관계식(關係式)은 $R_n(+)=0.7295{\cdot}R_s$로 흐린날에 옥수수 군락(群落)의 일사량(日射量)에 대(對)한 주간순복사량비율(晝間純輻射量比率)이 약간 큰 경향(傾向)이었다. 3. 복사수지식(輻射收支式)을 이용(利用)하여 일사량(日射量)과 기온(氣溫)으로 주간순복사량(晝間純輻射量)의 추정식(推定式) {$(0.9R_s-(352-227{\times}10^{-10}{\times}Ta^4) (1.11R_s/R_{so}-0.05)$}을 얻었다.

• Journal of Ecology and Environment
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• 제42권1호
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• pp.20-29
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• 2018

Background: For various reasons such as agricultural and economical purposes, land-use changes are rapidly increasing not only in Korea but also in the world, leading to shifts in the characteristics of local carbon cycle. Therefore, in order to understand the large-scale ecosystem carbon cycle, it is necessary first to understand vegetation on this local scale. As a result, it is essential to comprehend change of the carbon balance attributed by the land-use changes. In this study, we attempt to understand accumulated soil carbon (ASC) and soil respiration (Rs) related to carbon cycle in two ecosystems, artificially turned forest into pastureland from forest and a native deciduous temperate forest, resulted from different land-use in the same area. Results: Rs were shown typical seasonal changes in the alpine pastureland (AP) and temperate deciduous forest (TDF). The annual average Rs was $160.5mg\;CO_2\;m^{-2}h^{-1}$ in the AP, but it was $405.1mg\;CO_2\;m^{-2}h^{-1}$ in the TDF, indicating that the Rs in the AP was lower about 54% than that in the TDF. Also, ASC in the AP was $124.49Mg\;C\;ha^{-1}$ from litter layer to 30-cm soil depth. The ASC was about $88.9Mg\;C\;ha^{-1}$, and it was 71.5% of that of the AP. The temperature factors in the AP was high about $4^{\circ}C$ on average compared to the TDF. In AP, it was observed high amount of sunlight entering near the soil surface which is related to high soil temperature is due to low canopy structure. This tendency is due to the smaller emission of organic carbon that is accumulated in the soil, which means a higher ASC in the AP compared to the TDF. Conclusions: The artificial transformation of natural ecosystems into different ecosystems is proceeding widely in the world as well as Korea. The change in land-use type is caused to make the different characteristics of carbon cycle and storage in same region. For evaluating and predicting the carbon cycle in the vegetation modified by the human activity, it is necessary to understand the carbon cycle and storage characteristics of natural ecosystems and converted ecosystems. In this study, we studied the characteristics of ecosystem carbon cycle using different forms in the same region. The land-use changes from a TDF to AP leads to changes in dominant vegetation. Removal of canopy increased light and temperature conditions and slightly decreased SMC during the growing season. Also, land-use change led to an increase of ASC and decrease of Rs in AP. In terms of ecosystem carbon sequestration, AP showed a greater amount of carbon stored in the soil due to sustained supply of above-ground liters and lower degradation rate (soil respiration) than TDF in the high mountains. This shows that TDF and AP do not have much difference in terms of storage and circulation of carbon because the amount of carbon in the forest biomass is stored in the soil in the AP.

• 대기
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• 제30권3호
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• pp.257-276
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• 2020

Faithful evaluation of the meteorological input is a prerequisite for a better understanding of air quality model performance. Despite the importance, the preliminary meteorological assessment has rarely been concerned. In this study, we aim to evaluate the performance of the Weather Research and Forecasting (WRF) model conducting a year-long high-resolution meteorological simulation in 2016 over the Seoul metropolitan area. The WRF model was configured based on a series of sensitivity simulations of initial/boundary meteorological conditions, land use mapping data, reanalysis grid nudging method, domain nesting method, and urban canopy model. The simulated results of winds, air temperature, and specific humidity in the atmospheric boundary layer (ABL) were evaluated following statistical evaluation guidance using the surface and upper meteorological measurements. The statistical evaluation results are presented. The model performance was interpreted acceptable for air quality modeling within the statistical criteria of complex conditions, showing consistent overestimation in wind speeds. Further statistical analysis showed that the meteorological model biases were highly systematic with systematic bias fractions (f_SB) of 20~50%. This study suggests that both the momentum exchange process of the surface layer and the ABL entrainment process should be investigated for further improvement of the model performance.

• 한국조경학회지
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• 제20권1호
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• pp.80-94
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• 1992

To inspect the changing of the forest soil and plants community structrure by air plooutand & acid rain during from September to November in 1990, the smapling sites were selected in the Piwon, Namsan and Kwangnung forest. In sites, plots were set up in Q. aliena forest at Piwon, Quercus mongolica and Pinus densiflora forest at Namsan and Q. mongolica and Pinus densiflora forest at Kwangnung. To obtain the individual number of trees, number of species, importance values and species diversity, using the Curtis & McIntosh methods. The results are following that; 1) In Pinus densiflora community, it was almost dominated by Q. spp. in the canopy layer and P. densiflora and Carpinus laxiflora through the subtree to shrub layer at Kwangnung. It wassaid that C. laxiflora is the climax species in moddle temperature zone. On the contrary, in Namsan forest, there is no appearance thesamplings of P. densiflora & C. laxiflora, but Styrax japonica and Stephanandra incisa that are acid-tolerance species are dominant ones. On the other hand, in Q. spp. community, Q. spp. and C. laxiflora are dominant ones. On the other hand, in Q. spp. community, Q. spp. and C. laxiflora are dominant species through all layer, and in addition C. cordata somewhat appear at Kwangnung. But at Namsan and Piwon forest, Q. mongolica & Q. aliena that were dominant species in canopy layer disappeared in the subtreeand shrub layer, and C. laxiflora and Corunus cordata absolutely disappeared. It were similarly dominated by Robinia pseudo-acacia, Styrax japonica, Sorbus alnifolia, Acer pseudo-sieboldianum, Rhododendrn mucronulatum and so on at Namsn and Piwon forest. In the light of these facts, it found out that disclimax was similar between Namsan and Piwon forest. 2) Species diversity and maximum species diversity were decreased in Kwangnumg, Namsan, Piwon in order. It was xpected that vegetational community was affected by environmental pollutant. 3) As the vegetational community structure analyses, using DCA technique among the ordination, ecological successional series are stopped to Q. spp. from P. densiflora at Namsan and Piwon, but that of Kwangnung is on the way that P. densiflora, Q. alena, C. laxiflora. It was obvi ously different from Namsan and Piwon. 4) In Q. spp. & P. densiflora community, the number of woody plants inNamsan & Piwon is much less than that of Kwangnung through all Layer. Especially, Piwon shown very severe difference. Through all community, the number of individuals of Piwon and Namsan are less than that of Kwangnung. Specially, that of the shrub layer is obvious. 5) In the growth rate of trees, it found out that all sites showed the growth decline phenomena. Especially, since in 1975, there have been the micro disclimax phenomena in Q. community of Kwangnung. 6) In the Q. community, soil acidity of Namsan & Piwon measured 4.57, 4.40 respectively. It was very strong acidity and far lower than that of Kwangnung. Also the content amount of Mg++ in Namsan & Piwon forest were still lower than Kwangnung.

• 원예과학기술지
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• 제16권3호
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• pp.350-351
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• 1998

시설재배에서 반사필름 멀칭이 금어초의 생육 및 개화에 미치는 효과를 알아보고자 시험하였다. 반사필름의 파장(300nm-1100nm)별 광투과특성은 전체광의 85%를 반사시켰고, 대조구인 흑색PE필름은 95%이상을 흡수하였다. 처리별 군락 내 미기상은 반사필름 멀칭구에서 광량 및 기온, 엽온이 높았으며, 지온과 지중전열량은 흑색필름멀칭구에서 높았다. 초기생육은 반사필름 멀칭구에서 건물중과 줄기경도, 도복율, 증산활동 등에서 우수하였다. 또한 반사필름 멀칭처리로 대조구에 비해 개화가 12일 앞당겨졌고, 이때 절화 품질면에서도 우수하였다.

• 한국농림기상학회지
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• 제6권3호
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• pp.149-163
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• 2004

Evapotranspiration (ET) is a critical component of the hydrologic cycle which influences economic activities as well as the natural ecosystem. While there have been numerous studies on ET estimation for homogeneous areas using point measurements of meteorological variables, monitoring of spatial ET has not been possible at landscape - or watershed - scales. We propose a site-specific application of the land surface model, which is enabled by spatially interpolated input data at the desired resolution. Gyunggi Province of South Korea was divided into a regular grid of 10 million cells with 30m spacing and hourly temperature, humidity, wind, precipitation and solar irradiance were estimated for each grid cell by spatial interpolation of synoptic weather data. Topoclimatology models were used to accommodate effects of topography in a spatial interpolation procedure, including cold air drainage on nocturnal temperature and solar irradiance on daytime temperature. Satellite remote sensing data were used to classify the vegetation type of each grid cell, and corresponding spatial attributes including soil texture, canopy structure, and phenological features were identified. All data were fed into a standalone version of SiB2(Simple Biosphere Model 2) to simulate latent heat flux at each grid cell. A computer program was written for data management in the cell - based SiB2 operation such as extracting input data for SiB2 from grid matrices and recombining the output data back to the grid format. ET estimates at selected grid cells were validated against the actual measurement of latent heat fluxes by eddy covariance measurement. We applied this system to obtain the spatial ET of the study area on a continuous basis for the 2001-2003 period. The results showed a strong feasibility of using spatial - data driven land surface models for operational monitoring of regional ET.