• 한국환경농학회지
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• 제19권3호
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• pp.242-246
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• 2000

1999년도에 영농기인 5월부터 12월까지 매월 초에 농업용수로 사용하고 있는 서호에서 수질의 화학성분변화와 농업용수로서의 수질 적합성을 평가하기 위해 본 연구를 수행하였다. $COD_{Cr}$의 경우 평균 47.82mg/L로 나타났으나, 5월과 7월에는 83.07mg/L, 80.64mg/L로 나타났다. 5월의 경우 강우량 감소로 인한 수질의 악화를 7월에는 조류의 번식에 따른 수질악화로 판단된다. $NH_3-N$의 평균농도는 2.84mg/L로 나타났으며, 5월이 5.72mg/L로 조사기간중 가장 높았다. 암모니아 농도의 연변화는 $COD_{Cr}$와 유사한 경향을 나타내었다. 또한 호소내 수질의 오염도는 정체부에서 다른 조사지점들의 농도보다 높았으나, 전반적으로 서호의 수질의 연평균농도는 농작물피해의 기준농도보다 낮았다. 서호 등의 농업용수원으로 사용되는 호소의 지속적으로 양호한 농업용수 수질을 확보하기 위해서는 보다 적극적인 연구 및 관리대책이 필요하다.

• 한국환경농학회지
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• 제26권2호
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• pp.116-123
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• 2007

수원지역 영농기 빗물의 중금속 농도 및 부하특성을 구명하기 위하여 2002과 2003년 $4\sim10$월 사이에 빗물을 채수하여 빗물의 중금속 분포와 가중평균 변화, 화학성분과의 관계 및 부하정도를 비교 검토하였다. 빗물 중 화학성분 함량은 조사 시기에 따라 함량변이가 심하였고, 강우량 대비 pH의 가중평균은 $4.7\sim5.5$ 수준이었다. 빗물의 중금속 가중평균은 Zn>Pb>Cu>Ni>Cr>As>Cd 순이었고, 2002년과 비교하여 2003년에 Cd, Cu 및 As 성분이 상대적으로 높게 나타났다. 강우중의 주 이온성분과 중금속 함량의 관계는 모든 성분에서 정의 상관을 보였고, 상관계수로 볼 때 As, Cd, Cu, Zn 및 Ni 성분이 Pb 및 Cr보다 상대적으로 상관성이 큰 것으로 나타났다. 강우중의 중금속 농도분포를 이해하기 위하여 부하계수(Enrichment factors)를 조사한 결과, 부하계수 평균치가 대체로 Cd>Pb>As>Cu>Zn>Ni>Cr 순이었고, 주로 자연적 발생 유래원소로 알려진 Fe, Mg 및 Ca 등보다 상대적으로 높은 경향을 보였다. 월별 빗물의 중금속 부하계수는 봄철인 $4\sim5$월이 높았고, 중금속의 습식침적은 대체로 강우량의 영향을 받아 강우기인 6-8월에 높은 경향을 보였다.

• 한국산림과학회지
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• 제89권5호
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• pp.685-690
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• 2000

1996년부터 경상북도 상주시 소재의 신갈나무림에 남포잎벌(Caliroa carinata Zombori)이 대발생하여 많은 피해를 주고 있으나 우리 나라에서는 본 해충에 대해 행해진 연구가 전무한 실정이다. 이에 그 생태를 조사하고 방제를 위한 약제시험을 실시하였다. 성충의 우화시기는 6월 8일부터 7월 5일로 약 1개월간 지속되었고 그 우화최성기는 6월 18일이었다. 암컷 성충은 잎 표면에 산란관을 꽂고 잎 뒷면의 엽맥에 일열로 산란하며, 산란수는 평균 11개였다. 유충은 6령까지 발육하며 발육기간은 $20^{\circ}C$에서 약 19일, $25^{\circ}C$에서 약 17일이었고 영기별로는 2-4일의 발육기간을 보였다. 본 종의 참나무류에 대한 기주 선호성을 조사한 바, 신갈나무와 떡갈나무를 가장 선호하였고, 밤나무 선호성이 낮았으며, 굴참나무는 전혀 섭식하지 않았다. 또한 유충기에 테부페노자이드 액상수화제, 플루페녹수론 분산성액제, 에토펜프록스 유제, 페니트로치온 유제 등을 피해잎에 살포하고 처리 3일 후의 살충율을 조사한 결과 공시약종 공히 95% 이상의 높은 살충율을 보였다. 본 해충의 약제방제적기는 6월하순-7월상순으로 사료되었다.

• The Korean Journal of Ecology
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• 제20권6호
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• pp.413-421
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• 1997

Ecological characteristics of Rumex acetosella have been studied both in the laboratory and in the field. R. acetosella grows well straight up after germination, elongating and thickening their rhizomes with sprouts erupting along their bodies of the rhizome. The number and development of leaves and ramets reach their peak by April. The size of leaves and the cover degree of the plant increase from April to May. R. acetosella is an ephemeral, a short life mode plant, finishing its life cycle in July or August. The germination and seedling growth of selected species exposed to aqueous extracts of R. acetosella were in inverse proportion to concentration. The growth of Rumex japonicus and Digitaria sanguinalis cultivated in soil with R. acetosella was more inhibited than that of the control. Twelve chemical compounds were identified from R. acetosella by GC and HPLC and verified by bioassay with the same chemical reagents. It would be assdumed that these chemical substances are responsible for the allelopathic effect of R. acetosella. In short, R. acetosella plants grow vigorously from April and maintain their superior competitive ability to other plants in forming their communities by emitting chemical substances into their environment.

• The Korean Journal of Ecology
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• 제20권3호
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• pp.157-162
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• 1997

Changes on soil physical and chemical properties following the forest fire in Kosung area in Kangwon province were examined. Twenty seven sampling plots[16 burned (8 low intensity fire, 8 high intensity fire) and 11 unburned plots] from Pinus densiflora community were chosen and soil samples from three depths(0-5, 5-15, 15-25 cm) under the forest floor were collected. Forest fire in the area affected soil chemical properties. Soil pH, available phosphorus, base saturation, K, Ca, and Mg on the surface soil(0-5cm) in the burned areas compared with the unburned areas were increased, while soil properties on the subsurface soil(5-25 cm) were not changed. Organic matter, total nitrogen, available phosphorus, and exchangeable cations following the high in tensity fire on the surface soil were generally lower than those in the low intensity fire areas. This indicates that these nutrients on high intensity fire areas may be volatilized. The results suggest that the fire effects on soil chemical properties were confined mainly to the surface soil and were different between the high and the low intensity fire types.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1999년도 임시총회 및 추계 학술발표회
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• pp.55.1-55
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• 1999

• Applied Microscopy
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• 제50권
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• pp.10.1-10.6
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• 2020

Plant specimens for scanning electron microscopy (SEM) are commonly treated using standard protocols. Conventional fixatives consist of toxic chemicals such as glutaraldehyde, paraformaldehyde, and osmium tetroxide. In 1996, methanol fixation was reported as a rapid alternative to the standard protocols. If specimens are immersed in methanol for 30 s or longer and critical-point dried, they appear to be comparable in preservation quality to those treated with the chemical fixatives. A modified version that consists of methanol fixation and ethanol dehydration was effective at preserving the tissue morphology and dimensions. These solvent-based fixation and dehydration protocols are regarded as rapid and simple alternatives to standard protocols for SEM of plants.

• 한국환경농학회지
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• 제22권3호
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• pp.192-196
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• 2003

Objective of this study was to investigate the influences of harvest index and percolation water quality as irrigated the discharge waters from an industrial and a municipal wastewater treatment plants and seawater (1:5 seawater: tap water) as alternative water resources during tillering stage for drought stress. There were four different treatments such as the discharge water from an industrial (textile dyeing manufacture plant) wastewater treatment plant (DIWT), discharge water from the municipal wastewater treatment plant (DMWT), seawater (1:5) and groundwater as a control. For the initial chemical compositions of alternative waters, it appeared that higher concentrations of COD, $Mn^{2+}$, and $Ni^+$ in DIWT were observed than reused criteria of other country for irrigation, and concentrations of $EC_i$, Cl, and $SO_4$ in seawater were higher than that for irrigation. Harvest index was not significantly different between DIWT and DMWT with different irrigation periods in two soil types, but that of seawater (1:5) is decreased with irrigation periods in clay loam soil and not different between 10 days and 20 days of irrigation periods in sandy loam soil. For percolation water qualities, values of sodium adsorption ratio (SAR) are increased with prolonging the irrigation periods of seawater (1:5) and DIWT, but those of DMWT were almost constant through the cultivation periods regardless of the irrigation period in both soil types. EG of percolation waters is eventually increased with prolonging days after irrigation regardless of irrigation periods in both soil types. Therefore, it might be concluded that there was potentially safe to irrigate the discharge water from municipal wastewater treatment plant relative to harvest index, SAR and $EC_i$ values of the ground water through the rice cultivation period at tillering stage for drought period.

• The Korean Journal of Ecology
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• 제8권1호
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• pp.31-37
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• 1985

The decomposition rate of litter and the number of soil microorganisms were measured on various slope directions in deciduous oak forest in Mt. Yongam. And the chemical constitutents of litter and soil were analyzed. The decomposition rate by slope directions followed the order east facing slope>south-east facing slope>north-west facing slope>north-east facing slope>north facing slope>south facing slope>south-west facing slope>west facing slope. Of the chemical constituents analyzed, original concentrations of Ca and carbohydrate were closely correlated with the decomposition rate. There was a close relation between the number of fungi and decomposition rate by slope directions. However, a little relationship existed between the number of bacteria and decomposition rate by slope directions. The number of fungi and concentrations of Ca and carbohydrate correlated to each other. And the number of bacteria is related to concentrations of phosphorus.

• The Korean Journal of Ecology
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• 제8권1호
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• pp.21-29
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• 1985

The physico-chemical properties of sediment, the species composition and biomass of benthic diatoms were investigated in the intertidal zone of Kum river estuary, from July 1983 to May 1984. Sandflat sediment was more oligotrophic than mudflat one. The diatom composition was primarily associated with sediment grain size. The dominant epipelic diatoms belonged to the centric diatoms such as Paralia sulcata and Thalassiosira spp., while the epipsammic diatoms consisted mainly of Achnanthes haukiana and Amphora sabyii. Diatom flora of sandflat was more significantly diverse than that of mudflat. Mean yearly crop of sandflat diatoms was 2.8 times greater than that of mudflat diatoms and peaked at March reflecting the greater availability of ammonia.