• 한국농림기상학회지
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• 제20권4호
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• pp.386-396
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• 2018

농경지는 농업부문에서 배출되는 온실가스인 아산화질소와 이산화탄소의 공급원이다. 하지만 대부분 농경지 온실가스 배출연구는 경작기에 집중되어 있고, 휴경기 동안 거의 수행되지 않았다. 따라서 본 연구는 동절기 휴경 농경지 $N_2O$와 $CO_2$ 배출량과 주요 환경요인과의 유의확률 및 경작기 배출량과 비교하였다. 휴경기동안 녹비작물로써 H.V.와 Rye를 재배하였을 때, $N_2O$는 $0.014{\sim}2.956mg\;N_2O\;m^{-2}{\cdot}d^{-1}$ 범위로 배출되었으며, 누적량은 대조구, H.V.처리구, Rye처리구에서 각각 104.4, 85.8 그리고 $85.0mg\;N_2O\;m^{-2}$ 배출되었다. 대조구에서 배출량이 가장 높았으며, H.V. 및 Rye 처리구는 비슷했다. 누적 이산화탄소 배출량은 대조구, H.V. 처리구, Rye 처리구에서 각각 293.1, 242.2 그리고 $275.2g\;CO_2\;m^{-2}$ 배출되었다. 그리고 휴경기간동안 $N_2O$ 및 $CO_2$ 일 평균배출량은 경작기의 각각 28.3%, 27.4% 배출되었다.

• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.133-142
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• 2020

Soil physical and chemical properties at three layers such as top (0-10 cm), middle (10-20 cm) and bottom (20-30 cm) layers under three different vegetation types were studied. Soil samples were collected from Acacia forest, vegetable and fallow lands of Chittagong university campus, Chittagong, Bangladesh. Results showed that sand was the dominant soil particle followed by clay and silt fractions in all soil depths under different vegetation types. Soils of fallow land showed the highest values of bulk density while forest soils had the lowest values at three depths. Acacia forest soil having lowest values of dispersion ratio (DR) is less vulnerable while fallow soil with highest DR values is more vulnerable to soil erosion. The lower pH value at all soil layers in three ecosystems represented that soils under study are acidic in nature. Contents of organic matter, total nitrogen, exchangeable cations (Ca²⁺, Mg²⁺, K⁺ and Na⁺) and cation exchange capacity (CEC) were observed higher in Acacia forest soils compared to vegetable and fallow soils. Only soils of vegetable land had higher level of available phosphorus in three layers than that of other two land covers. The study also revealed that different soil properties were observed in three different vegetation types might be due to variation in vegetation and agronomic practices.

• Journal of Biosystems Engineering
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• 제28권2호
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• pp.107-116
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• 2003

One of the major obstructing factors against managing dairy farm in Korea has been a shortage of roughage supply. The shortage of roughage caused excessive use of concentrate feed increase of production cost and deterioration of cattle quality. In order to solve this problem for the dairy farm, use of fallow paddy field in the winter was feasible to produce barley and rye forage during the winter season after harvesting of in. And many desirable effects of raising cattle productivity, saving dollars for importing feeds and providing huge ground for manure spreading are expected by enlarged local roughage production. Through analysing the forage producing process, a mechanized operation model was developed for dairy farms in Korea. Its model consists of seeding models(till, no-till model) and harvesting models(wrap silage, traditional silage, hay model). Currently, the government policies are being executed to urge producing winter cereal wrap silage in the fallow paddy field with various supporting programs. Ant with enlarged local forage production, it is possible to make a new huge market fur forage producing machine.

• Asian-Australasian Journal of Animal Sciences
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• 제15권2호
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• pp.209-212
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• 2002

The understanding of seasonal forage intake of grazing deer is essential for the development of supplementary feeding strategies in southern Australia. The alkane technique is used in other animal species for estimating feed intake of individual animals and their diet composition. To assess the potential of using alkanes as a marker for predicting feed intake of fallow deer, the daily faecal recovery of alkanes and excretion rate of dosed artificial alkanes (C32 and C36) were measured with 6 deer fed three forage based diets. The artificial alkane capsule designed for use in sheep is suitable for fallow deer. Faecal samples need to be collected over days 7-19 after dosing. The daily excretion rate was 40 mg for C32 and 37 mg for C36. The faecal recovery of natural alkanes is incomplete and the faecal concentrations of alkanes need to be adjusted for an accurate estimation of intake. The actual feed intake of 6 experimental deer over a 5 day period was accurately estimated ($R^2$=0.52) using alkanes.

• 한국농공학회지
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• 제36권1호
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• pp.73-82
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• 1994

This paper presents the experimental results of runoff and soil losses from sloping runoff plots under three cropping practices. Twenty-nine runoff plots having slopes of 10, 20, and 30 percent in gradient, and lengths of 10, 20 and 30 meter, respectively, were cultivated with soybean, alfalfa, and fallow conditions during 1989~1990 seasons. Crop stages were grouped based on crop canopy conditions and the cropping management factors of the Univer- sal Soil Loss Equation were derived as ratios of the soil losses to fallow conditions. The results from this study are summarized as follows : 1. Annual rainfall erosivity factor at Ichun station varied from 127 to 1336, averaging 472 and 200 in 1989. The month variations reach the peak in July, being 19& 2. Canopy cover percent for soybean that was taken by a photographic method increased sharply during 30 to 80 days after seeding and the results were used to identify periods for the six crop stages. 3. Annual average runoff rates from soybean and alfalfa plots were 35 and 16 percent of those from fallow ones, respectively. The runoff rates decreased as the crops grew. 4. Soil losses from soybean and alfalfa plots were 14 and 16 percent of those from fallow plots. And the crop coefficients were proposed for different crop stages.

• 환경영향평가
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• 제15권6호
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• pp.357-372
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• 2006

The excessive land activities in farming can cause soil erosion, inundation by a flood, and fallow. So far land evaluation has been analyzed using the land use limitation derived from the excessive land activities. This study was done for evaluating the agricultural fields by using 3 land use limitations, inundation potential, soil erodibility potential, and fallow potential. The study area is Ibang-myeon, Changnyeong-gun, Gyeongnam-province, Korea. A logistic regression model was applied to recognize the inundation potential by a flood in the Nakdong river basin. And potential soil erodibility index (PSEI) was derived from USLE model to analyze the soil erodibility potential. And a probability model from a logistic regression model was applied to detect the fallow potential. Therefore, we found 220.7ha for the 4th grade and 86.1ha for the 5th grade was analyzed as water damage potential. Large area near Nakdong river have problem to grow the rice due to the damage by water inundation. And 213.6ha for the 3rd grade and 103.3ha for 4th grade was detected as a result of the analysis of soil erosion potential. The soil erosion potential was high when within-field integrity of soil was not stable, or the kinetic energy was high or the slope length was long due to a steep slope of a specific land. And 869.1ha for 3rd grade, 174.9ha for 4th grade, and 110.6ha for 5th grade was detected to be distributed having the fallow potential. Especially, a village, having a steep mountain, had 249.5ha for the 3rd grade, which was 28.7% of total area showing the 3rd grade. Finally, Three villages, including An-ri, Geonam-ri, Songgok-ri, showed they had largest area of the suitable land in the study area. These villages had similar topographic condition where they were far from Nakdong river, and they had relatively higher elevation and flat lands.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.638-642
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• 2004

In Australia, many cropping areas are affected by salt. In these regions, Chenopodiaceous plants, such as Atriplex, Kochia and Bassia spp have been planted to improve soil conditions. These plants have become invaluable feed resources for grazing animals in dry summers, but have a high sodium content. To assess the impact of high salt intake on grazing deer, two experiments were conducted. The first experiment used 30 fallow weaner deer to examine the effect of salt level in the diet on feed intake, water intake and body weight of fallow deer. Salt was added to lucerne chaff at 0, 1.5, 3.0, 4.5 and 6% and fresh water was offered all the time. Increasing the salt level in the diet from 0 to 6% didn't affect feed intake, osmotic pressure and mineral concentration in blood of fallow deer. However, water intake was significantly higher (p<0.05) in deer fed diets containing more than 3% salt. Body weight was lower (p${\leq}$0.056) for fallow deer in July and August when salt content was over 3%, suggesting they can ingest over 15 g sodium/day without significant depression in both feed intake and growth rate if the fresh water is available. In the second experiment, 18 red weaner deer were fed lucerne chaff diets containing 1.5, 4.5 and 6.0% salt with 6 deer/diet. The results revealed that feed intake and blood osmotic pressure were similar (p>0.05) for red deer fed different levels of salt although the feed intake declined from 1.91 to 1.67 kg with the increase of salt level from 1.5% to 6.0% in the diet. Water intake was significantly higher for deer fed diets containing over 4.5% salt, but there was no difference in body weight during the experiment. However, no recommendation can be made on the salt tolerance of red deer due to limited increment of salt level in the diet.

• 한국지역지리학회지
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• 제7권3호
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• pp.74-90
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• 2001

한국의 과소농촌지역에서의 휴경화는 지난 30년간의 급격한 산업화 도시화로 인한 격심한 인구 유출에 따른 사회변화에 농촌지역사회와 농민의 토지이용방식 및 이농민의 농지처리가 미처 대응하지 못해 나타난 결과이다. 과소지역인 경북 상주시 사벌면 덕가리를 연구한 결과는 다음과 같다. 첫째, 인구의 급격한 감소로 인한 농촌 노동력의 질적 저하 양적 부족은 만성적인 농지 공급과잉이 초래되었다. 촌락 내 노동력의 절대적 부족 상태에서 경작조건 불리 농지의 우선적 휴경화가 진행되고 있다. 둘째, 노동력의 상대적 부족 상태, 즉 집약적 노동 투입 또는 노동력 배분 우선 순위에 따라서 자기 소유의 땅이라도 경작 조건이 나쁠 경우는 휴경하고, 조건이 좋은 땅을 임차하여 경영 규모를 확대한다. 셋째, 이농민의 토지 보유 성향과 상속, 매매 부진으로 인한 부재지주 소유농지의 증가는 휴경화를 촉진하는 주요한 요인이다. 노령자의 질병 사망으로 인한 농가 소멸이나 비농가화(非農家化), 촌락 내 노동력의 부족은 부재지주 소유 농지의 우선적 휴경화를 촉진시킨다. 경사도가 높거나 경작조건이 불리한 경지는 부재지주 소유농지를 중심으로 휴경화가 광범위하게 이루어지고 있다. 덕가리 부재지주의 휴경지는 이촌 이농형 문중답 위토형의 2가지 유형으로 구분된다. 한국농촌의 휴경화는 압축적 산업화에 따른 인구유출로 인한 노동력의 양 질적 부족, 경작불리 지의 방치, 농업의 수지조건 악화 등의 사회경제적 요인과 부재지주 농지의 온존 증가와 같은 문화적 요인이 주 요인으로 작용하고 있다. 본 연구에서는 인구유출로 인한 과소화가 광범위하게 일어나고 있는 원격지 과소농촌지역에서의 휴경화에 대한 분석을 하였다. 따라서 또 하나의 한국적 현상인 대도시주변지역에서 나타나는 일시적, 투기적 휴경현상에 대한 분석이 이루어져야 설명력이 증가되고 전체적인 휴경화 현상을 설명할 수 있을 것이다.

• 한국응용곤충학회지
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• 제48권3호
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• pp.285-294
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• 2009

2004년에서 2005년까지 전 남북지역 휴경 논에 발생하는 식물, 해충 및 천적의 발생종류 및 발생정도를 조사하였다. 휴경 논에 발생하는 식물 종은 32과 124종, 해충은 30과 58종, 천적은 9과 11종 이었다. 식물 종은 벼과(Poaceae)와 국화과(Asteraceae)가 각각 28, 18종으로 발생량이 많았으며, 해충은 쌕새기, 애긴노린재, 시골가시허리노린재, 가시점둥글노린재, 끝동매미충, 애멸구 및 각다귀 1종의 발생량이 많았다. 휴경 논에 발생하는 해충 중 끝동매미충과 애멸구는 $5{\sim}6$월에 발생이 가장 적었고, 애멸구는 $8{\sim}9$월에 발생량이 가장 많았다. 천적곤충으로는 실잠자리류, 무당벌레, 꼬마남생이무당벌레, 꽃등에의 발생이 많았다.

• 한국작물학회지
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• 제45권5호
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• pp.294-299
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• 2000

Hairy vetch (Vicia villosa Roth) winter annual is very effective on reducing chemical nitrogen fertilizer for subsequent com by fixed organic green manure nitrogen fixed during hairy vetch growth. In this experiment, hairy vetch produced above-ground dry matter of 5 ton/ha, nitrogen yield 200 kgN/ha, at com planting on the average during 1997 and 1998. Changes in com yield and nitrogen uptake for two years were investigated after application of nitrogen fertilizer 0, 60, 120, 180, 240 kgN/ha on plot of winter fallow and hairy vetch green manure, respectively. Nitrogen status such as ear-leaf N%, SPAD value at silk and dough stage, and com yield decreased in proportion to reduction of nitrogen fertilizer at winter fallow, but nitrogen status and yield of com were not different among nitrogen fertilizer rate at hairy vetch green manure. Com yield (total dry matter) at 0 kgN/ha plot of hairy vetch was 22, 20 ton/ha in 1997, 1998, respectively and com could produce more dry matter 9, 13 ton/ha by hairy vetch green manure compared with winter fallow under the condition of no nitrogen fertilizer in 1997, 1998, respectively. Com yield (total dry matter) at 60kgN/ha of hairy vetch green manure was higher than that of high N fertilizer rate such as 180, 240 kgN/ha of winter fallow. Nitrogen uptake of com at plot of hairy vetch-no nitrogen fertilizer slightly decreased than at plot of hairy vetch - nitrogen fertilizer, but com absorbed more nitrogen of 141, 159 kgN/ha by hairy vetch green manure compared with winter fallow under no nitrogen fertilizer condition in 1997, 1998, respectively. Nitrogen fertilizer reduction for com by hairy vetch green manure was 149, 161kgN/ha in 1997, 1998, respectively. Still more, com could absorb more soil nitrogen by nitrogen fertilizer 60kgN/ha of hairy vetch green manure than by high nitrogen fertilizer such as 180, 240 kgN/ha at winter fallow. It is concluded that nitrogen fertilizer for corn could be reduced by winter cultivation and soil incorporation of hairy vetch at com planting.