• 한국환경농학회지
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• 제34권3호
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• pp.192-195
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• 2015

BACKGROUND: The growing season (GS) has been understood as a useful indicator for climate change due to high relationship with increasing temperature. Hear this study was conducted to examine changes in the thermal GS over South Korea from 1970 to 2013 based on daily mean air temperature for assessing the temporal and spatial variability in GS. METHODS AND RESULTS: Three GS parameters (starting date, ending date, and length) were determined at 19 stations throughout South Korea. The results show that the GS has been extended by 4.2 days/decade between 1970 and 2013 on average. The growing season start (GSS) has been advanced by 2.7 days/decade and the growing season end (GSE) has been delayed by 1.4 day/decade. Spatial variation in the GS parameters in Korea are shown. The GS parameters, especially GSS, of southeastern part of Korea have been changed more than that of northwestern part of Korea. The extension of GS may be more influenced on earlier onset in spring rather than later GSE. CONCLUSION: Under climate change scenarios, the GS will be more extended due to delayed GSE as well as advanced GSS. And These are more notable in the northeastern part of Korea.

• Journal of Ginseng Research
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• 제12권2호
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• pp.145-152
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• 1988

Correlations between various morphological characteristics of Panax quinquefolium plants grown in Lytton, British Columbia, Canada were assessed for 1-through 4-year old plants. Root dry weight, the dependent variable, was found to be strongly related to leaf dry weight, leaf length and root length for 1-and 2-year old plants during the middle of the growing season. For 1- and 2-year old plants at the end of the growing season, root dry weight was found to be related to leaf dry weight, leaf length and stem dry weight. For 3 and 4-year old plants, root dry weight was found to be related to leaf dry weight, leaf length and stem dry weight. For 3- and 4-year old plants, root dry weight was found to be related to leaf dry weight. For practical considerations, this latter relationship provides a simple method for selecting superior plants from which seed can be harvested.

• 한국작물학회지
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• 제23권2호
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• pp.126-132
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• 1978

To examine the effects of P.E. film and rice straw mulching on fall grown potato(Shimabara cultivar) in the middle region of Korea, sprouted seed tuber pieces were transplanted with six kinds of mulching treatments on 24th July and harvested on 25th October. P.E. film mulching from transplanting resulted the perfect rot of transplanted seed pieces due to the excessive high soil temperature (noon soil temperature of about 4$0^{\circ}C$ continued until the middle of August). P.E. film mulching from 15th September to harvest increased the marketable tuber yields by 35% due to the raising of soil temperature by 1-3$^{\circ}C$ and maintaining of available soil moisture in dry season. Rice straw (whole or cut in 10cm length) mulching lowered the soil temperature in hot season and raised it in cool season and maintained available soil moisture in dry season. Therefore better emergence, growth and yields were induced. Effects of whole straw, whole growing season and thicker mulching were greater than cut straw, half growing season and thinner mulching. 6cm mulching of whole or cut straw during whole growing season resulted the increasing of marketable tuber yields by 56 or 48%.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.198-198
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• 2022

최근 도시화에 따른 토지 피복 변화와 열섬현상 등의 원인으로 상승하는 도시의 기온이 식물 계절에 미치는 영향에 관한 연구들이 다수 진행되고 있다. 본 연구는 수도권인 서울과 경기도 지역을 대상으로 도시 내 열섬현상으로 인한 기온 상승과 도시 지역 내 식생 생장기간 변화의 관계성을 분석하였다. 식물계절 모니터링에 사용한 개량식생지수(Enhanced Vegetation Index, EVI)는 Google Earth Engine (GEE)에서 제공하는 30 m 해상도의 2000-2021년 NASA-USGS Landsat 위성(TM5, ETM+7, OLI8)의 지표면 반사율(surface reflectance, SR) 자료에서 도출하여 생장기간 산정에 사용하였다. 또한 PRISM (Parameter-elevation Regressions on Independent Slopes Model)을 각 기상관측지점의 일별 지상 기온 자료에 적용하여 30 m 해상도로 생성한 격자형 지표면 온도의 공간적 패턴을 분석하였다. 연구 지역 내 도시화 정도(magnitude)를 도심으로부터의 거리와 환경부 토지피복도 및 인구 밀도를 종합하여 특정하였고, 최종적으로 기후변화 및 도시화 정도와 생장기간 변화의 특징을 분석하였다. 비선형 로지스틱 회귀를 사용하여 EVI 데이터를 종합하여 분석한 결과, 수도권 지역에서 전반적으로 식물계절 개엽일(Start of Season)은 앞당겨지며 낙엽일(End of Season, EOS)은 늦춰져 생장기간(Length of Growing Season, LOS)이 길어짐을 발견하였다.

• 한국환경복원기술학회지
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• 제13권1호
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• pp.82-92
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• 2010

Removal rates of NO3-N and TN in a free water surface wetland system during emergent plant growing season and non-growing were investigated. The system was established on floodplain in the down reach of the Gwangju Stream in 2008. Its dimensions were 46 meters in length and 5 meters in width. Typha angustifloria L. growing in pots about two years were planted on the half area of the system and Zizania latifolia Turcz on the other half. Water of the stream was funneled into it by gravity flow and its effluent was discharged back into it. Volumes and water quality of inflow and outflow were analyzed from October 2008 to September 2009. Inflow into the system averaged approximately 715 $m^3$/day and hydraulic residence time was about 1.5 hr. Average influent and effluent $NO_3$-N concentration was 3.37 and 2.74 mg/L, respectively and $NO_3$-N retention amounted to 18.7%. Influent and effluent TN concentration averaged 4.67 and 3.69 mg/L, respectively and TN abatement reached to 20.9%. $NO_3$-N removal rate (%) during plant growing season ($22.67{\pm}3.70$, mean ${\pm}$ standard error) was significantly high (p<0.001) when compared with that during plant non-growing one ($15.02{\pm}3.23$). TN abatement rate (%) during plant growing season ($27.42{\pm}5.98$) was also significantly high (p<0.001) when compared with that during plant non-growing one ($13.66{\pm}3.08$).

• 한국환경복원기술학회지
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• 제9권2호
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• pp.23-32
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• 2006

Total suspended solids (TSS), five-day biochemical oxygen demand ($BOD_5$), total nitrogen (T-N), and total phosphorous (T-P) concentrations around and under a floating island were examined from October 2002 to September 2003. The island was installed in July 2002 on the surface of an agricultural irrigation reservoir located in the southern part of the Korean Peninsula. It was composed of six polyethylene panels. Each panel was 2 m (length) ${\times}$ 1 m (width) ${\times}$ 0.02 m (thick) and had about thirty-two holes each with a diameter of eight centimeters, through which plant roots grew down into the water. Coconut fibers of nine-centimeters in height were placed on the panel, which sustained plants rhizomes and roots. Both the fibers and the panel were raped with polyethylene wire mashes. About thirty irises (Iris pseudoacorus) were planted into the fibers of each panel. The concentrations of TSS, $BOD_5$, T-N and T-P below the island during the iris-growing season averaged 9.70, 2.59, 3.61 and 0.14 mg/L, respectively and those around it averaged 9.99, 2.83, 4.07 and 0.16 mg/L, respectively. The average concentrations of TSS, $BOD_5$, T-N and T-P below it during the iris non-growing season were 8.68, 2.37, 3.25 and 0.14 mg/L, respectively and those near it were 8.76, 2.43, 3.34 and 0.15 mg/L, respectively. At a significance level of ${\alpha}$=0.05, $BOD_5$, T-N and T-P concentrations under the island during the iris-growing season were significantly low when compared with those around it except TSS. No differences in TSS, $BOD_5$, T-N and T-P concentrations between around and near it were found at a significance level of ${\alpha}$=0.05 during the iris non-growing season. The removal of $BOD_5$, T-N, and T-P during the growing season were significantly high when compared with those during the non-growing season. TSS abatement of the floating island was very low during both the growing and non-growing seasons. The island's reductions of $BOD_5$, T-N and T-P were good during the growing season, especially T-N and T-P, which have been considered as primary pollutant sources causing the water quality degradation of reservoirs. The removal of T-N and T-P was primarily attributed to the absorption of nitrogen and phosphorous by the irises during the growing season.

• 한국물환경학회지
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• 제28권1호
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• pp.94-101
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• 2012

The performance data for eight years from a free-surface-flow constructed wetland system receiving agricultural tailwater were used to analyze denitrification rate and nitrogen treatment characteristics according to season and wetland design. Seasonal difference between growing season (March~November) and winter season (December~February) was shown in the concentration of all nitrogen species. Seasonal nitrogen treatment has similar trend with temperature and measured denitrification rate. The highest denitrification rate was measured in July, but treatment efficiency was most higher in May and June. Nitrogen absorption of vegetation could affect to these wetland performances, therefore dense population of wetland vegetation might be helpful. According to design of wetland, at least 25~50 m of wetland length was needed to decrease effluent T-N concentration to background concentration in growing season. In winter season, wetland needed much longer distance to reduce T-N concentration. Mass removal rate was continuously high through whole year because runoff coefficient was low in winter season. Applicability of constructed wetland was observed for the total maximum daily load that control T-N load.

• 한국기후변화학회지
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• 제5권4호
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• pp.285-289
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• 2014

The extension of growing season (GS) across the Northern Hemisphere have been linked to increasing temperature, related with global warming. Therefore, in this study, The start, end, and length of GS in Suwon, Korea from 1971 to 2013 based on observed daily mean air temperature are examined using three indices. The GS starts on average after $98.598.5{\pm}1.42$ Julian days and ends after $318.7{\pm}1.08$ Julian days. The average length of GS is $220.2{\pm}2.09$ Julian days. The length of GS in Suwon from 1971 to 2013 has been extended by 6.8 days/decade with an earlier onset of the GS (-4.1 days/decade) and later end of the GS (2.7 days/decade). This change may be due to an advanced start of the GS in spring rather than later end of the GS. In further study, it is necessary to select an index carefully to find the most suitable one for Korea.

• 한국물환경학회지
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• 제25권5호
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• pp.713-719
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• 2009

A natural wetland in the Nakdong River basin which effectively removes non-point source pollutants was investigated for 2 years to understand wetland topography, vegetation types, and water quality characteristics. The water depth of the natural wetland was in the range of 0.5~1.9 m which is suitable for the growth of non-emergent hydrophytes. The wetland has a high length to width ratio (3.3:1) and a relatively large wetland to watershed area ratio (0.057). A broad-crested weir at the outlet increases the retention time of the wetland whose hydrology is mainly dependent on storm events. The concentrations of dissolved oxygen in the growing season and the winter season showed anoxic and oxic conditions, respectively. Diurnal variations of DO and pH in the growing season were also observed due to weather change and submerged plants. COD and TP concentrations were low in the winter season due to low inflow rate and increased retention time. Increased TP concentrations in the spring season were caused by degradation of dead wetland plants. Nitrogen in the wetland was mostly in organic nitrogen form (>75%). During the growing season, ammonium concentration was high but nitrate nitrogen concentration was low, possibly due to anoxic and low pH conditions which are adverse conditions for ammonificaiton and nitrification. The results of this study can be used as preliminary data for design, operation, monitoring and management of a constructed wetland which is designed to treat diffuse pollutants in the Nakdong river watershed.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권1호
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• pp.65-68
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• 2005

Growth and development of a plant over a growing season is closely related to the daily accumulation of heat. Heat unit measured by accumulated growing degree days (GDD) is becoming increasingly popular to estimate the growth of a plant or even in insect. GDD or heat accumulation per day is measured by calculating average daily temperature and then subtracting the base temperature below which growth does not occur. Heat accumulation per day is added for the desired period and accumulated GDD is determined. The present study was conducted in five seasons in an established garden with K-2, S-36 and V-1 mulberry varieties belonging to Morus indica L. grown under completely irrigated condition at the farm of CSRTI, Mysore during 2001 - 2002. Plants were pruned in each season and the growth of the plant measured by total shoot length and fresh leaf yield was recorded at an interval of 5 days starting from 30 days of pruning (DAP) to 70 days when all the plants were pruned. The accumulated GDD for the corresponding days were recorded and used for analysis. Accumulated growing degree days (GDD) have been found to be perfectly correlated with both growth and yield in all the seasons in all the varieties studied. The high $R^2$ values indicated a strong relationship between the accumulated GDD and, growth and yield of mulberry.