• 한국농촌건축학회논문집
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• 제7권1호
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• pp.19-30
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• 2005

This study is carried out to understand the characteristic of location in vernacular agricultural villages by judging from natural environment around the village. For this purpose, there were selected 17 villages of the riverside villages in Geosan Area which lean against Dalchoen River. After classifying these samples by the morphorogical approach, according to compare them with pre-researched villages, the methodology of spatial structure was investigated in agricultural villages. As a result of the study, the relationship between the agricultural villages and the shape of Dalcheon River can be classified by 3 types that are twisted around villages, attacked villages, and paralleled with villages. First of all, twisted type is located in river terraces, river safety zone and taken a image of the riverside agricultural village. Secondary, attacked type is located in beside riffle, and taken a image of a fishing village. Finally, paralleled type is located in straightly flowing river.

• Journal of Ecology and Environment
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• 제29권2호
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• pp.125-141
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• 2006

Insect fauna in adjacent areas of Demilitarized Zone (DMZ) in Korea was surveyed seasonally in $2001{\sim}2003$. The survey area was divided into 3 regions (eastern mountain, middle inland, and western coastal regions) in accordance with administrative districts and topography. Sampling methods such as sweeping, sieving, beating, brushing and suction were used depending on the environmental and military conditions. Total 361 genera and 437 species of 116 families belonging to 14 orders were identified. Among these, 46 species were new to insect fauna of DMZ areas. Species richness was the highest in the eastern mountain region. Numbers of habitat-common and -specific species were 96 (22%) and 195 (47.2%), respectively. The insect species community similarity was highest (0.64) between eastern mountain region and western coastal region. Insect orders showing high species richness were Coleoptera (38.9%), Lepidoptera (19.2%), Orthoptera (9.4%), and Hemiptera (9.2%). These results will be useful information for study of history on the change of insect fauna and future conservation in DMZ areas.

• Asian-Australasian Journal of Animal Sciences
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• 제3권3호
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• pp.219-223
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• 1990

Sixtyfour Baluchi lambs about 5 months of age were divided into four groups with 16 lambs each. All the animals were grazed together. Group No.1 (G-1) was kept as control i.e. on grazing only; while group No. 2 (G-2) was offered barley grain @ 200 g/head/day as supplement to grazing; Group No. 3 (G-3) was offered ad-lib urea-molasses block (UMB) with 6% cement and group No.4 (G-4) was fed ad-lib IMB having 8% cement. These UMB were fed as supplement to grazing. Experiment lasted for 105 days (July to October) in arid zone of Baluchistan. Daily per head consumption of block No.1 was found to be 92.71 g; while that of block No.2 was observed to be 90.77 g. Growth rate (g/head/day) was found to be 10, 50, 33 and 15 in G-1, G-2, G-3 and G-4 respectively. Expenditure/kg bodyweight gain was found to be rupees 12.00, 3.64 and 7.74 for G-2, G-3 and G-4 respectively.

• Mycobiology
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• 제35권1호
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• pp.21-24
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• 2007

To evaluate which dye is effective in a plate assay for detecting extracellular cellulase activity produced by fungi, four chromogenic dyes including remazol brilliant blue, phenol red, congo red, and tryphan blue, were compared using chromagepic media. For the comparison, 19 fungal species belonging to three phyla, ascomycota, basidiomycota, and zygomycota were inoculated onto yeast nitrogen-based media containing different carbon substrates such as cellulose (carboxylmethyl and avicel types) and cellobiose labeled with each of the four dyes. Overall, the formation of clear zone on agar media resulting from the degradation of the substrates by the enzymes secreted from the test fungi was most apparent with media containing congo red. The detection frequency of cellulase activity was also most high on congo red-supplemented media. The results of this study showed that congo red is better dye than other three dyes in, a plate assay for, fungal enzyme detection.

• 한국농공학회논문집
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• 제63권6호
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• pp.49-60
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• 2021

BCSA (Bias-Correction and Stochastic Analog) is a statistical downscaling technique designed to effectively correct the systematic errors of GCM (General Circulation Model) output and reproduce basic statistics and spatial variability of the observed precipitation filed. In this study, the applicability of BCSA was evaluated using the ASOS observation data over South Korea, which belongs to the monsoon climatic zone with large spatial variability of rainfall and different rainfall characteristics. The results presented the reproducibility of temporal and spatial variability of daily precipitation in various manners. As a result of comparing the spatial correlation with the observation data, it was found that the reproducibility of various climate indices including the average spatial correlation (variability) of rainfall events in South Korea was superior to the raw GCM output. In addition, the needs of future related studies to improve BCSA, such as supplementing algorithms to reduce calculation time, enhancing reproducibility of temporal rainfall patterns, and evaluating applicability to other meteorological factors, were pointed out. The results of this study can be used as the logical background for applying BCSA for reproducing spatial details of the rainfall characteristic over the Korean Peninsula.

• 한국농공학회논문집
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• 제64권3호
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• pp.53-61
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• 2022

This study evaluated the impacts of subsurface drainage design, i.e., spacing and depth, on agricultural productivity and environmental sustainability in two tile-drained fields (Sites A and E) under a corn-soybean rotation in the Midwestern United States. A calibrated and validated Root Zone Water Quality Model (RZWQM) was used to simulate Nitrate-N (nitrogen) losses to tile drainage and crop yields of 30 tile spacing and depth scenarios over 24 years (1992-2015). Our results presented that the narrower and deeper the tile drains are placed, the greater corn yield and Nitrate-N losses, indicating that the subsurface drainage design may cause a trade-off between agricultural productivity and environmental sustainability. The simulation results also presented that up to about 255.7% and 628.0% increase in Nitrate-N losses in Sites A and E, respectively, far outweigh the rate of increase in corn yield up to about 1.1% and 1.6% from the adjustment of tile spacing and depth. Meanwhile, the crop yield and Nitrate-N losses according to the tile configuration differed depending on the field, and the soybean yield presented inconsistent simulation results, unlike the corn yield, which together demonstrate the heterogeneous characteristic of agro-environmental systems to a subsurface drainage practice. This study demonstrates the applicability of agricultural systems models in exploring agro-environmental responses to subsurface drainage practices, which can help guide the introduction and installation of tile systems into farmlands, e.g., orchards and paddy fields, in our country.

• 농약과학회지
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• 제3권3호
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• pp.60-67
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• 1999

흡즙성 해충과 저작성 해충 및 천적에 대한 imidacloprid의 살충력을 처리방법별로 조사하였다. 흡즙성 해충인 벼멸구에 대하여 imidacloprid의 미량국소처리에 의한 $LD_{50}$은 $0.015{\mu}g/g$ (48시간)이었으며, 유묘침지와 근부처리시의 $LD_{50}$은 각각 21.5 와 18.1 ppm을 보였으며, 처리간의 살충력 차이는 보이지 않았다. Imidacloprid 액제를 근부처리를 하였을 경우 20 ppm에서도 살란효과가 99%을 보였으며, 반수살란농도는 6.8 ppm이었다. 복숭아혹진딧물에 대한 imidacloprid의 $LD_{50}$은 $0.4{\mu}g/g$(48시간)이었으며, 엽침지처리와 근부처리 48시간 후 $LC_{50}$은 각각 1.9과, 13.7ppm으로 엽침지처리에 의한 살충효과가 높았다. 저작성 해충인 담배거세미나방과 파밤나방에 대한 imidacloprid의 $LD_{50}$은 1492.5이상과 $3125{\mu}g/g$으로 살충력이 낮았으며, 엽침지처리에 의한 $LC_{50}$은 각각 4803.3과 5000 ppm 이상을 보여 imidacloprid는 흡즙성 해충보다 저작성 해충에 대해 살충력이 낮았다. 배회성거미인 황산적거미(Pirata subpiraticus)와 턱거미(Pachygnata clercki)에 대한 $LD_{50}$이 각각 294.1과 $2976.3{\mu}g/g$ 이상으로 독성이 매우 낮았으며, 조망성거미인 등줄가슴애접시거미(Ummeliata insecticeps)에 대한 $LD_{50}$은 357.1 ${\mu}g/g$로 역시 독성이 낮았다. Imidacloprid의 거미류와 벼멸구간 선택독성은 각각 196,000 이상과 199,000이상 및 23,800이상으로서 독성이 벼멸구에는 높은 반면 거미류에는 낮았다.

• 한국수자원학회논문집
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• 제50권6호
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• pp.387-395
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• 2017

기후변화에 따른 해수면 상승으로 인하여 해안지역의 지하수계에 해수침투가 가중된다. 지하수의 염분농도가 증가하면 지하수면 상부의 불포화 토양에서도 염분 농도가 증가할 수 있으며, 이는 농경지에서 작물피해를 일으킬 수 있다. 해수면이 상승함에 따라 내륙의 지하수위도 함께 상승한다. 이는 불포화 토양층의 두께를 감소시켜 해안 저지대의 경작에 피해를 끼칠 수 있다. 본 연구에서 지하수 해수침투는 3차원 모델, 토양 염류화 평가는 연직 1차원 모델을 합성 적용하여 해안 농경지에 대한 해수면 상승 피해를 평가하는 방법을 개발하였다. 3차원 해수침투 모델에서 지하수면의 수위와 농도분포를 계산하고 최상부 절점 중에서 염분 농도가 기준 값 이상인 절점에서 지하수면과 지표면 사이의 토양층에서 연직 1차원 모델링으로 토양층의 염분 농도와 불포화대 두께를 계산하였다. 농경지의 토양 염류화는 작물의 뿌리 심도에서 보통 작물의 생육한계 염분농도를 기준으로 판단하였다. 개발된 모델링 방법을 가상의 간척농경지에 적용하였다. 해수면 상승자료로 IPCC의 RCP 4.5와 8.5 시나리오를 사용하였다. 평가 결과는 2050년과 2100년에 대하여 제시하였다. 연구결과 대상지역에서 기후변화 시나리오 RCP 8.5에서 2100년에는 지하수 염류화 피해 면적은 간척지 육지면적 대비 7.8%, 염류화 토양 면적은 6.0%, 불포화층의 두께가 뿌리심도보다 적은 지역의 면적은 1.6% 증가하는 것으로 분석되었다.

• 한국지역지리학회지
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• 제3권2호
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• pp.121-150
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• 1997

본 연구는 경북의 사례지역 비교분석을 통하여 임차농의 지역성을 밝히는 것이 목적이다. 이를 위하여 대구시의 농업 공간체계(대략 경상북도와 일치)를 대상으로 중심도시에서의 거리와 영농형태에 따라 5개 군(郡)을 연구대상지역으로 선정한 후 각 군을 대표하는 마을(이동(里洞))을 택하여 총 77개 임차농가에 대한 설문조사를 무작위로 행하였다. 연구지역의 범위가 제한적이면서도 분석의 결과는 임차농의 지역성을 잘 드러내고 있다. 이러한 지역성은 특정 공간체계가 형성하는 공간질서와 이 공간질서내에서 특정 장소가 발현하는 국지성이 결합하여 형성된 것이다. 이 경우의 공간질서는 주로 거리조락으로 나타나고 국지성은 지역의 고유한 자연환경과 인구요인의 차이에서 발현된다. 한편 본 연구지역의 지역성을 포괄적으로 파악할 수 있는 기본 기준은 지역농업의 상업화 정도인데 그것은 한국의 임차농이 봉건적 소작농에서 자본주의적 차지농(借地農)으로 이행하는 과도기에 있기 때문이다. 이상과 같은 임차농의 현저한 지역성은 기존의 획일적인 임차농 설명논리의 현실 괴리문제를 제기하였다.

• 한국농공학회논문집
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• 제64권6호
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• pp.65-75
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• 2022

Livestock industry in Korea has been growing rapidly and has reached 23 trillion Korean won in 2021. This study focuses on broiler, which is one of the largest sectors in livestock industry. As the effects of climate change get more serious, primary industry such as livestock industry is fragile to climate change since it directly interacts with nature. Therefore, maintaining suitable rearing environment is important. One of the most frequently used ventilation type for controlling the rearing environment of broiler house, tunnel ventilation, causes frequent air velocity fluctuation which makes maintaining the rearing environment important. By measuring the air temperature, relative humidity and air velocity in various points inside the broiler house, the internal thermal environment uniformity was analyzed according to length, width and zone. The experimental house was found to have dead zone with high air temperature, relative humidity and low air velocity near the end of the inlet and at the end of the broiler house. By using heat stress index to analyze quantitatively, zone with highest heat stress index was found to increase by 7.55% compared to the lowest zone. As a result, to maintain uniform rearing environment inside the broiler house, different factors must be measured and analyzed and used to operate the environmental control facilities.