• 인간식물환경학회지
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• 제23권5호
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• pp.507-519
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• 2020

Background and objective: This study analyzed the growth characteristics, in relation to the soil moisture content, of trees planted in an environment with limited soil depth to provide the baseline data for effective irrigation management. Methods: The experimental treatment was divided into soil moisture contents (SMC) of 20%, 15%, 10%, 5%, and 1%, and the respective watering times were set accordingly. As for plant materials, Nandina domestica, Euonymus alatus, Thuja occidentalis, Hibiscus syriacus, Pinus densiflora, and Pyracantha angustifolia, were chosen for this study, because they are highly likely to be used in urban street environments. Results: The minimum irrigation point suitable for each species was determined by considering various aspects of visual quality and water efficiency in terms of plant growth, including characteristics such as height, root diameter, rootlet development, and weight. Our results indicate that N. domestica should be watered so that the moisture content of the soil is of at least 5%, based on the balance between the stem and roots, as well as on visual quality. E. alatus and P. angustifolia are suitable for watering that results in at least 10% SMC, considering the height, root growth, weight, and visual quality of plants. As for T. occidentalis, it showcases moderate growth with a soil moisture content of at least 5%. Finally, the minimum irrigation time required to obtain 15% SMC is appropriate, in terms of plant growth, fresh weight, and visual quality, for H. syriacus and P. densiflora. Conclusion: This study suggested a basic irrigation guideline for container gardens where trees planted in environments with limited soil depth can be managed so that they are visually appropriate and in good condition of growth.

• 생명과학회지
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• 제8권3호
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• pp.294-297
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• 1998

본 연구는 이식시기와 물관리 방법이 율무의 수량에 미치는 영향을 아아보기 위함이었는데, 그 결과는 아래와 같이 요약된다. 1. 율무의 이식후 초기생육은 배수처리구에서 양호하였고 침수처리구는 이식 1개월 이후부터 생육이 점차 회복되었다. 2. 이식시기가 늦어질수록 이식-출수하까지의 기간이 크게 단축되었으며 율무의 제특성 발현 및 첫서리 이전에 수확을 하기 위해서는 6월 20일이 율무 이식한계기였다. 3. 율무는 침수 재배조건하에서 간장은 단축되었으나 결실립수 및 1,000립중은 증가하였으며, 엽고도 감소되어 배수처리구에 비해 종실수량이 8% 증수되었다.

• 한국환경과학회지
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• 제19권7호
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• pp.843-848
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• 2010

This study focused on the characteristics of change soil water with respect to soil thickness and soil mixture ratio, in order to effectively carry out an afforestation system for a roof with a low level of management and a light weight. Soil hardness tended to increase as sand particle was increase regardless soil thickness and soil porosity had more higher artificial soil than natural soil mixture. In case of soil pH, natural soil mixture had between 6.7 and 7.4, and artificial soil mixture had 6.0~6.8. Organic matter, electrical conductance and exchangeable content were highest in $L_{10}$, which it had the highest leafmold ratio. Soil moisture tension(kPa) in 15cm soil thickness was observed natural soil mixture had a considerable change but artificial soil mixture had a gradual change when non-rainfall kept on. In the experimental $L_{10}$, $S_{10}$, $S_7L_3$ and $S_5L_5$ object, the amount of moisture tended to rapidly decrease. However, in the experimental $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$ and $P_4P_4L_2$ objects, which contained pearlite and peat moss, the amount of moisture tended to gradually decrease. As a result, the use of a artificial soil mixture soil seems to be required for the afforestation of a roof for a low level of management.

• 한국농공학회논문집
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• 제57권3호
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• pp.65-76
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• 2015

Estimating water requirements for upland crops are characterized by standing soil moisture condition during the entire crop growth period. However, scarce rainfall and intermittent dry spells often cause soil moisture depletion resulting in unsaturated condition in the fields. Changes in rainfall patterns due to climate change have significant influence on the increasing the occurrence of extreme soil moisture depletion. Therefore, it is necessary to evaluate agricultural drought for upland crop water planning and management in the context of climate change. The objective of this study is to predict the impacts of climate change on agricultural drought for upland crops and changes in the temporal trends of drought characteristics. First, the changes in crop evapotranspiration and soil moisture in the six upland crops, such as Soybeans, Maize, Potatoes, Red Peppers, Chinese Cabbage (spring and fall) were analyzed by applying the soil moisture model from commonly available crop and soil characteristics and climate data, and were analyzed for the past 30 years (1981-2010), and Representative Concentration Pathways (RCP) climate change scenarios (2011-2100). Second, the changes on the temporal trends of drought characteristics were performed using run theory, which was used to compare drought duration, severity, and magnitude to allow for quantitative evaluations under past and future climate conditions.

• The Plant Pathology Journal
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• 제20권2호
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• pp.92-96
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• 2004

Environmental factors such as soil moisture, land management, and weather conditions affecting Fusarium wilt of sweet potato were investigated in major sweet potato cultivation regions in Korea. Fusarium wilt occurred mainly in reclaimed terracing lands, which are flattened and located in hilly to mountainous areas at the base of the mountain, in early seasonal cultivation regions. Disease severity was lower in reclaimed fields with natural slope. The development of Fusarium wilt in the fields was highly correlated with precipitation during planting period (r=-0.96**). Fusarium wilt was more severe in fields with less than 20 cm of available soil depth than in fields with over 20 cm of available soil depth. Greenhouse studies were consistent with field studies that less soil moisture content caused severe Fusarium wilt of sweet potato. These results indicate that low rainfall and moisture of soil with low effective soil depth during planting period are important environmental factors influencing the development of Fusarium wilt.

• 한국작물학회지
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• 제44권1호
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• pp.32-37
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• 1999

The experiment was conducted to investigate emergence response of lowland weeds at different soil moisture contents, burying depths and upon changes in soil moisture. Rice germination was over 50% at all burying depths under aerobic condition, but the emergence rate of the soil surface placed seeds in saturated and flooded conditions decreased by 19% and 29%, respectively, as compared with that of aerobic condition. Rice seeds at burying depth of over 3 cm did not emerge at all. The emergence rate of Echinochloa crus­galli (L.) Beauv. in aerobic condition was lower than 30%, but the emergence pattern of E. crus galli (L.) Beauv. at different soil moisture contents and seeding depths was similar to that of rice. Emergence behavior of lschaemum rugosum Salisb., Ludwigia octovalvis (Jacq.) Raven and Sphenoclea zeylanica Gaertn. which are dominant lowland weed species in the Philippines also differed depending on soil moisture conditions and burying depths. lschaemum rugosum Salisb. emerged at all burying depths under aerobic condition, whereasLudwigia octovalvis (Jacq.) Raven emerged only at 0 cm deep under saturated and aerobic condition and Sphenoclea zeylanica Gaertn. at 0 cm deep under flooding condition. Weed seeds planted at 1, 3, and 5 cm deep in continuous flooded and saturated condition did not emerge at all, but upon a change of soil moisture condition from saturated to drainage (S$\rightarrow$D) and flooded to drainage (F$\rightarrow$D), grass weeds began to germinate again and the average emergence rate in S$\rightarrow$D and F$\rightarrow$D were 26% and 5% forE. crus­galIi (L.) Beauv., 9% and 8% forI. rugosum SaIisb., respectively. Weed seeds buried in soil in the pot showed great emergence at S$\rightarrow$D but did not emerge under continuous flooded condition. The diversity index accounting for dominance degree and occurrence aspect of weed, was the lowest at F$\rightarrow$D.

• 농업과학연구
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• 제41권4호
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• pp.399-404
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• 2014

Soil moisture is an important factor for the availability and circulation of nutrients in arable soil. The purpose of this study was to set thresholds moisture content on soil nitrate concentration in the solution for real-time diagnosis. Sandy loam, silt loam, and sandy loam was filled with $1.2g\;cm^{-3}$ at Wagner pots, 0, 100, and $200mg\;L^{-1}$ of $KNO_3$ was saturated. Nitrate in standard solution was recovered about 95% by passing the porous cup. Nitrate concentrations in sampling of soil solution were examined by using a porous cup. The soil solution was higher in accordance with sandy loam> silt loam> clay loam, limited water filled pore space for sampling soil solution was 33.7, 56.4, and 62.2%, respectively. Nitrate concentration in the soil solution was negligible at sandy loam and silt loam during sampling periods, which was decreased about 50~82% in clay loam compared to the initial $NO_3$-N concentration in the saturated $KNO_3$ solution. Over limitation of soil solution sampling, soil EC and $NO_3$-N content were increased with the saturated $NO_3$-N concentration, regardless of soil texture (p<0.05). Conclusively, soil solution by using a porous cup was possible, regardless of the soil texture, which was useful for the diagnosis in nitrate concentration of soil solution. However, because nitrate concentration of soil solution in a clay loam changes, it was necessary for careful attention in order to take advantage for the real-time diagnosis of nitrogen management in soil.

• 한국토양비료학회지
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• 제45권2호
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• pp.127-134
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• 2012

다편파 레이더 산란계 시스템 (L, C, X-밴드 안테나)에서 얻어진 편파별 후방산란계수와 토양수분함량과의 상관성을 분석하고 후방산란계수를 이용 토양수분함량을 추정하고자 하였다. 콩 생육시기에 따른 밴드별 후방산란계수 변화 관측 결과 L-밴드 후방산란계수가 C-, X-밴드후방산란계수보다 높게 나타났고, 모든 안테나 밴드에서 콩 생육초기에는 VV-편파가 HH, HV-편파보다 후방산란계수가 높게 나타났다. HH-편파가 VV-편파보다 후방산란계수가 높게 나타나는 시기는 밴드에 따라 차이를 보였다. L-밴드의 경우 7월 20일 (DOY 200), C, X-밴드는 7월 30일 (DOY 210)부터 HH-편파가 다른 편파들 보다 후방산란계수가 높게 나타났다. 모든 안테나 편파별 후방산란계수가 9월 29일 (DOY 271)에 최대값을 보였고, 그 이후 수확기 (DOY 294) 까지 감소하였다. L-밴드 HH-편파와 VV-편파 간의 차이는 꼬투리가 생성되는 착협기 (R3, DOY 228) 부터 다른 밴드에 비해 크게 나타났고, 반면에 C-밴드 HH-편파와 VV-편파 간의 차이는 착협성기 (R4, DOY 242) 이후 증가폭이 크게 나타났다. 후방산란계수와 토양수분함량과의 변화를 분석한 결과 생육기간동안 토양수분함량 변이가 컸고, 전체 생육기간에서는 모든 밴드별 후방산란계수와 토양수분함량 간에 상관성이 나타나지 않았다. 하지만 엽면적지수가 2 이하 (R2, DOY 224) 일 때 후방산란계수가 증가함에 따라 토양수분함량도 증가하는 경향을 보였다. 밴드별 후방산란계수와 토양수분함량과의 상관관계를 분석하였다. 전체 생육기간에서는 모든 밴드에서 두 변수간의 상관계수가 낮게 나타났다 ($r{\leq}0.50$). 반면에 엽면적지수 2 이하 일 때 모든 밴드에서 후방산란계수와 토양수분함량과의 상관계수가 전체 생육단계에서 조사한 것 보다 높게 나타났다. L-밴드 후방산란계수가 C-, X-밴드 후방산란계수 보다 토양수분함량과의 상관성이 높게 나타났고 ($r{\geq}0.84$), L-밴드 HH-편파가 상관계수가 가장 높았다 (r=0.90). X-밴드 후방산란계수는 L-, C-밴드 후방산란계수보다 상관계수가 낮게 나타났다 ($r{\leq}0.71$). 후방산란계수를 이용하여 토양수분함량 추정 모형식을 작성하였다. L-밴드 HH-편파 후방산란계수와 토양수분함량과의 관계를 비교해 본 결과 결정계수가 높게 나타났다($R^2=0.92$). 본 연구를 통해 레이더 산란계 시스템에서 얻어진 후방산란계수를 이용하여 토양수분함량을 추정할 수 있음을 확인하였다.

• 한국환경생태학회지
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• 제27권6호
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• pp.745-756
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• 2013

본 연구는 옥상녹화 시 식물유형별 수분요구도에 대한 사항을 사전에 고려하여 저관리, 최소한의 관리로 조성되는 옥상녹화의 지속가능성을 유지하고자 하는 데에 목적을 두고 있다. 따라서 옥상녹화의 대표적인 식물로 알려진 세덤류 중 애기기린초와 내건성이 강한 일반 초화류 중 상록패랭이가 동일 조건에서 건조에 견디는 저항력과 토양종류별 토양수분감소에 대한 생육변화를 살펴보고자 실험을 수행하였다. 무관수, 무강우 조건에서 30일 경과 후 상록패랭이가 식재된 펄라이트 10cm 토양이 토양 내 수분함량이 가장 적은 것으로 나타났고, 애기기린초가 식재된 인공배합토 20cm의 토양이 다른 토양에 비해 가장 많은 수분함량을 나타냈다. 또한 전반적으로 토양종류와 토심에 관계없이 애기기린초가 식재된 토양구보다 상록패랭이가 식재된 토양실험구의 수분함량이 낮은 것으로 나타났다. 이는 상록패랭이의 수분요구도가 애기기린초보다 더 크다는 사실을 증명하는 결과라 할 수 있다. 또한 식물의 생육상태는 펄라이트 토양중에서도 토심이 낮은 10cm, 인공배합토양에서도 20cm 실험구보다 10cm 실험구에서 더 양호한 결과가 도출되었다. 본 실험결과 무강우 무관수 조건에서 토양 종류에 따라 토양수분의 감소패턴에 큰 차이가 있음을 알 수 있었으며, 식물 종류에 따라서도 토양수분감소에 따른 수분스트레스 패턴의 차이가 있음을 알 수 있었다.

• 한국환경농학회지
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• 제25권2호
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• pp.164-169
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• 2006

착과량을 달리한 '후지'/M.9 품종에서 생육 최성기중 토양수분 변화에 따른 수액 이동 특성과 수체 생리반응을 조사하였다. 적정 착과는 적습 조건인 -50 kPa에서 VPD 및 최대증발산량과 비슷한 양상의 수액이동량을 보였으나 과다 착과는 -50 kPa 및 -80 kPa 조건에서 최대증발산량보다 낮은 수액흡수량을 보였다. 적정 착과는 모든 토양수분 조건에서 최대증발산량보다 일중 $1.06{\sim}3.93L$ 많은 수액이 이동되는 특성을 보였고 과다 착과는 적정 착과보다 토양수분 -50 kPa 조건에서 21%, -20 kPa과 -80 kPa에서 $31{\sim}36%$ 정도 낮은 수액 이동량을 보였다. 착과 처리에 따른 신초생육과 엽면적은 적정 착과 처리구가 다른 처리구보다 유의성 있게 높았으나 과다 착과 처리구는 가장 낮았다. 적정 착과 처리구의 엽수분포텐셜은 다른 처리구에 비해 모든 토양수분 조건에서 가장 낮아서 수분소모율이 가장 높았다. 따라서 '후지'/M.9 품종은 적정 착과량 유지와 더불어 생육성기 중 적습조건을 유지하는 것이 수액이동을 고려할 경우, 증산효율을 높이는데 바람직할 것으로 판단되었다.