• 한국작물학회지
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• 제41권4호
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• pp.411-419
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• 1996

보리입모중 벼 파종에 있어서 보리짚 시용에 따른 경운방법과 질소시용량별 관개수중에 용출된 각 성분함량 변화를 검토하였던 바, 그 결과를 요약하면 다음과 같다. 1. pH는 무경운재배에서는 시비수준간 차리가 없었으나 경운재배에서는 컸으며, 10일까지는 시비수준이 높을수록 pH가 높았으나 그 이후는 비슷하였다. 2. EC는 무경운에 비해 경운재배에서 높았으며, 경운의 유 ㆍ무에 관계없이 시비수준이 높을수록 EC도 높았다. 시기별로 보면 10일에 최고수준에 도달하였다가 그 후 감소경향이나, 20일에는 초기와는 달리 시비수준이 높을수록 EC가 감소하였고, 그 감소폭은 경운재배에서 컸다. 3. 용존산소는 무경운에 비해 경운에서 높았으며, 시비량이 많을수록 낮은 경향을 보였다. 경운방법별로는 무경운에서는 시용후일수가 경과됨에 따라 다소 증가하는 경향이었으며, 무처리에 비해 매우 낮았으나, 경운재배에서는 초기에 매우 높고 10일에 급격히 감소하였으며 그 후 다시 증가하였다. 4. NH$_4$-N는 경운의 유 ㆍ무에 관계없이 시비수준이 높을수록 높았으나, 20일에는 시비량간 차이는 없었다. 경운방법간에는 무경운에서는 10일까지 높고 그 후 감소를 보였으나 경운에서는 초기(5일)에 매우 높았다가 급격히 감소하였고, 15일에 다시 감소하였으나 20일에는 거의 발현되지 않았다. NO$_3$-N는 무경운에서는 처리일수 및 시비수준간의 차이가 매우 컸으며, 10일에 최고수준을 보였고, 그 후 20일까지 급격히 감소하였다. 경운구에서는 처리일수가 경과함에 따라 감소경향을 보였으나, 시비수준간 차이는 보이지 않았다. 5. PO$_4$$^{3-}$ 은 경운재배에 비해 무경운재배에서 높았으며, 두처리 모두 시비수준이 높을수록 높았으나, 무경운재배에 비하여 경운재배에서는 시일의 경과에 따라서도 차이가 크지 않았고 함량도 낮았다. 6. 양이온함량은 모두 경운 유 ㆍ무에 관계없이 시비수준이 높을수록 높은 경향을 보였고, 10일에 최고수준을 보인 후 완만한 감소를 나타냈으며, $K^{+}$, $Ca^{2+}$에 비해 $Mg^{2+}$이 보다 낮은 함량을 보였다.

• 한국잡초학회지
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• 제3권2호
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• pp.120-128
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• 1983

전국(全國) 맥류재배포장(麥類栽培圃場)의 전답(田畓) 및 각(各) 재배조건(載培條件)에 따른 잡초(雜草)의 발생(發生) 및 분포(分布)를 조사(調査)코자 1982 년(年) 월동전(越冬前) 12월(月)과 '83 월동후(越冬後) 3~4월(月)에 60 개군(個郡) 1,800 개(個) 지점(地點)을 대상(對象)으로 조사(調査)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 맥류재배포장(麥類栽培圃場)에 발생(發生)하는 주요(主要) 잡초(雜草)는 화본과(禾本科) 2종(種), 광엽잡초(廣葉雜草) 35종(種)이었으며, 이 중(中) 전작(田作)에 발생(發生)하는 것이 36종(種), 답리작(畓裏作)에 발생(發生)하는 것이 29종(種)이었다. 2. 생활형(生活型)으로 보면 월년생(越年生) 잡초(雜草)가 42~45%로 가장 많이 발생(發生)하였고 다음이 다년생(多年生), 일년생(一年生)의 순위(順位)였다. 3. 맥류재배포장(麥類栽培圃場)의 최우점(最優點) 잡초(雜草)는 전작(田作)에서 벌꽃과 독새풀이었고, 답리작(畓裏作)에서는 독새풀과 벼륙나물이었다. 4. 지역별(地域別) 잡초분포(雜草分布)는 어느 지역(地域)이나 월년생(越年生) 잡초(雜草)가 가장 많았는데 전작(田作)이 답리작(畓裏作)보다 또 남(南)쭉으로 갈수록 초종수(草種數) 많았다. 5. 재배(栽培) 양식별(樣式別) 잡초(雜草) 발생량(發生量)을 보면 관행파(慣行播)>광파(廣播)>휴립광산파(畦立廣散播)>협폭파(狹幅播)의 순서(順序)였고, 휴폭(畦幅)이 넓은 것이 잡초발생(雜草發生)이 많았다. 6. 무경운재배(無耕耘栽培)는 경운재배(耕耘栽培)보다 잡초발생수(雜草發生數)가 많았는데 월동전(越冬前)에는 일년생(一年生) 잡초(雜草)가 월동후(越冬後)에는 월년생(越年生) 잡초(雜草)가 많이 발생(發生)하였다. 7. 토양(土壤) 유형별(類型別)로 보면 전작(田作)에서는 사양토(砂壤土)와 양토(壤土)가, 답리작(畓裏作)에서는 보통답(普通畓)이 잡초발생량(雜草發生量)이 가장 많았다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.216-217
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• 2000

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 춘계학술발표회 요지
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• pp.80-81
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• 2005

• 한국작물학회:학술대회논문집
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• 한국작물학회 2006년도 한국약용작물학회 공동춘계학술발표회
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• pp.312-313
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• 2006

• 한국작물학회:학술대회논문집
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• 한국작물학회 2004년도 춘계 학술대회지
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• pp.188-189
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• 2004

• 농업과학연구
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• 제45권1호
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• pp.120-127
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• 2018

The rural labor force has gradually been decreasing due to the decrement of the farm population and the increment of the aging population. To solve these problems, it is necessary to develop and study autonomous agricultural machinery. Therefore, analyzing the dynamic behavior of vehicles in an autonomous agricultural environment is important. Until now, most studies on agricultural machinery, especially on ground vehicle dynamics, have been done by field tests. However, these field test methods are time consuming and costly with seasonal restrictions. A research method that can replace existing field test methods by using simulations is needed. In this study, we did basic research analyzing the effect of the travelling speed of a tractor on tire slip using simulation software. A tractor simulation model was developed based on field conditions following a straight path. The simulation was done for three ranges of speed: 20 - 30 km/h (considered the normal travelling speed range), 6 - 8 km/h (considered the plow tillage speed range) and 2 - 4 km/h (considered the rotary tillage speed range). The results of the simulation show that the slip ratio and slip angle values tended to increase as the traveling speed range of the tractor decreased. From the simulation results, it can be concluded that at low tractor speeds, it becomes more difficult to control the vehicle path. In future research, simulations will be done with various work environments such as a curved path as well as with various friction coefficient conditions, and the simulation results will be experimentally verified by applying them to an agricultural tractor.

• The Korean Journal of Ecology
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• 제28권4호
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• pp.181-188
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• 2005

Methods used to study carbon sequestration by soil aggregates have often excluded the concentric spatial variability and other dynamic processes that contribute to resource accessibility and solute transport within aggregates. We investigated the spatial gradients of carbon (C) and nitrogen (N) from the exterior to interior layers within macroaggregates, $6.3\sim9.5$ mm, sampled from conventional tillage (CT) and no tillage (NT) sites of a Hoytville silt clay loam. Spatial gradients in C accumulation within macroaggregates were related to the differences in C dynamics by determining the sizes and the turnover rates of fast C and slow C pools in the concentric layers of aggregates. Aggregate exteriors contained more labile C and were characterized by greater C mineralization rates than their interiors in both management systems. In contrast, C in the interior layers of aggregates was more resistant in both systems. These results indicated the spatial differentiation of C dynamics within macroaggregates, i.e., exterior layers as a reactive site and interior layers as a protective site. Greater total C distribution in the exterior layers of NT aggregates indicated more influx of C from the macropores in interaggregate space than C. mineralization (net gain of C), whereas lower C distribution within the exterior layers of CT aggregates indicated net loss of C by greater C mineralization than C influx. We found total C increased approximately 1.6-fold by the conversion of CT soils to NT management systems for a period of 36 years. Differences in total accumulation and the spatial distribution of C within aggregates affected by management were attributed to the differences in aggregate stability and pore networks controlling the spatial heterogeneities of resource availability and microbial activity within aggregates.

• 한국환경복원기술학회지
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• 제17권1호
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• pp.163-172
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• 2014

To investigate the possibility of developing the seeding measure for river bank slope revegetation, germination experiment and early growth observation were conducted using 3 native species growing naturally around river banks such as Pennisetum alopecuroides, Phragmites communis, and Miscanthus sinensis. The applied seeding methods were 3 such as scattering seeds, tillage after scattering seeds, and covering up seed with soil after scattering seeds. According to seeding methods, germination experiment and early growth observation were carried out on nursery bed soil in greenhouse. As results of this study, all the 3 native plant species' germination ratio and growth in length on nursery bed soil were highest on the seeding method of covering up seed with soil. Also it was verified by Duncan's multiple range test that the germination ratio and growth in length on the seeding method of covering up seed with soil is distinguished from those on other two seeding methods. According to this results, the best possible seeding measure to be developed should be mechanical seed spraying with soil.

• Journal of Biosystems Engineering
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• 제31권1호
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• pp.24-32
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• 2006

Compaction is becoming a greater concern in crop production and the environment because it can have deleterious effects on growing conditions that are difficult to remediate. Because compaction can vary considerably from point to point within a field, and also from depth to depth within the soil profile, it is important to consider quantification and management of the spatial and vertical variability in soil compaction when developing an overall site-specific crop management plan. In this paper, the importance of soil compaction, techniques for quantification of its variability, and the concept of site-specific tillage are examined. Methods and systems to detect within-field variation in soil strength as a surrogate measure of soil compaction and related soil properties are also compared and discussed. Quantification of variability in soil compaction and site-specific compaction management was motivated recently, and sensors and control systems are still under development. Future study will need to address a number of issues related to understanding and applying the sensor measurements.