• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.241-245
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• 2002

최근 시설재배에서는 염류 집적 및 토양전염성 병해충 등으로 인한 연작장해를 회피하기 위하여 수경재배로 전환하는 농가가 급속히 증가하고 있다. 우리나라의 수경재배면적은 '98년 23 ha에서 2000년 1,000 ha로 급속히 증가하고 있는데, 이중 약 12％는 담액수경이나 박막수경의 순수 수경재배 방식이 차지하고 있으나 대부분이 고형배지를 이용한 비순환방식이다. 배양액의 비순환방식은 토양이나 지하수의 오염이 염려되지만, 순환방식의 경우에는 배양액 성분의 조정이나 배양액의 소독 등재처리가 필요하여 농가에서는 기피하고 있는 실정이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1995.10a
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• pp.85-86
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• 1995

수경재배 방식은 고품질의 작물생산, 토지의 고도이용, 연중재배 등과 같은 측면에서 많은 관심을 같게 되었다. 최근 선진국을 중심으로 작물생산에서 종합적인 환경제어기술, 생산과정의 자동화 및 계획 생산을 목적으로 하는 식물공장이 등장하게 되었다. 그러나 이들 재배방식간에 작물생산과정에서 재배환경의 차이로 인한 작물의 생리생태적 변화를 연구한 문헌은 미흡한 편이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.92-94
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• 1998

최근 도시근교 시설재배토양의 염류 과다집적과 연작장해 발생으로 생산성이 저하되고 있다. 그리고 고품질 연중생산이 가능한 양액 재배 면적이 '93년 23ha에서 '97년 414ha로 급속히 증가되고 있는데 이 중 약12%가 담액경이나 박막수경의 순수 수경재배 방식이 차지하고 있다. 순환식 담액수경 상추재배를 기준으로 할 때 농가 300평 재배시 약 100ton의 양액이 소요되며 이 양액은 1회 재배가 끝난 후 상당량이 폐기되고 있고 고형 배지경 양액 재배의 경우에도 대부분 비 순환식 재배로 1회 관수 후 나오는 배액이 그대로 버려지고 이어 토양 및 지하수 등 환경오염, 자원 낭비 등의 여러 가지 문제를 야기시키고 있다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.390-395
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• 2003

우리나라의 수경재배 면적은 2001년말 현재 736㏊로 순환식이 296㏊, 비순환식이 440㏊를 차지하고 있다. 수경재배에서의 양액관리방법은 작물 및 재배시스템의 종류에 따라 다르지만 작물이 흡수하고 남은 양액이 양액탱크와 재배조사이를 왕복순환되는 순환방식과 양액탱크에서 재배조로 공급된 후 배출폐기되는 비순환방식(흘러버림식)으로 나누어진다. (중략)

• Horticultural Science & Technology
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• v.29 no.3
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• pp.195-200
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• 2011

The growth, yield and quality of Sedum sarmentosum between soil and hydroponic cultivation were compared to produce high-quality shoots in summer season. The plants were collected from four places in Korea and cultivated in a plastic film house with 50% shading. A 1:1:1 mixtures of sand, upland soil and substrate (N-P-K: 330-220-400 $mg{\cdot}L^{-1}$) was used for soil cultivation, and a nutrient film technique (NFT) with Yamazaki-lettuce nutrient solution used for hydroponics. After 30 days of cultivation, plant height ranged from 18.4 to 21.8 cm and showed no significant difference between soil and hydroponic cultivation. Number of shoot, leaf length, leaf width, number of leaf, fresh weight, and dry weight significantly increased in hydroponics compared to those in soil cultivation. Fresh and dry weights in hydroponics were greater in 'Gunsan' and 'Wando' collections than those in other collections. Stem diameter and compression-force significantly increased in soil cultivation rather than hydroponics with significant differences among collections. However there were no significant differences in shoot bitterness and vitamin C content between cultivation methods or among the collections. Most mineral contents except Fe in hydroponics were higher than those in soil cultivation. K, Na, Zn contents in hydroponics were over 2 times higher than those in soil cultivation.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.168-174
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• 2002

A new circulating hydroponic system was invented for oriental melons grown in the greenhouse. For developing nutrient solution management techniques, we examined the changes of nutrient contents of circulating solution in three different types of new hydroponic systems. The yield and fruit quality of oriental melons in Hydroponics were better than those in soil culture. The substrate culture was appropriate fer hydroponics of oriental melons, and NFT was turned to be the opposite due to the physiological disorder during hot seasons. Yamazaki's melon solution with EC 2.0dS.m$^{[-10]}$ was the most appropriate for oriental melons. The new circulating hydroponic system seemed to be appropriate for oriental melons because of the stable EC, pH and the macro- and micro-element contents. NO$_3$-N, Ca and Mg contents in the circulating solution kept a good balance in all types of hydroponics. However, p content, compared to other types, decreased by the degree of 1 me.L$^{[-10]}$ in perlite medium. K content showed irregular status in perlite but showed the stable status in cocopeat. Generally, microelements, except Mo, showed stable absorption in the substrate culture. However, in NET, most of the elements showed irregular absorption except B and Mn. Microelement absorption, especially Cu, Zn and Mo, decreased during hot seasons.

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.62-66
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• 2007

This study was carried out to develop the stable plug seedling production for hydroponics of spinaches by various nursery media, plug tray size and seed number per plug tray cell. When plant grown in various nursery media, the seeding stand rate was shown in order of granular rockwool with good water retention, granular rockwool>granular rockwool mixed with pearlite>cocopeat>pearlite>poly urethane foame. Thus, poly urethane foame indicated the lower seedling stand rate. There was no difference in growth of the seedlings md the seeding stand rate by the plug tray size, and no significant difference in the plant height and the number of leaves among the seed number per plug tray cell. But, leaf area of plant in 2 grains seeding per cell was $113.0cm^2$, was wider in compared with 5 grains seeding of which leaf area was $88.0cm^2$. Accordingly, the leaf area per plant decreased as more and more the number of seeds per plug tray cell increased. The fresh weight of a plant per plug tray cell was the heaviest with 12.5g in the 2 grains, and the total fresh weight of plants per cell was 33.9g in 4 grains seeding, thus it tended to was bigger compared with other treatments. Consequently, given that the number of seeds per cell was decreased, the fresh weight of a plant increased. On the other hand, the total fresh weight per cell showed a tendency to be reducing as more and more the number of seeds per plug tray cell decreased. The yield in the 4 grains seeding was increased by 46% as $14,910kg{\cdot}ha^{-1}$ in compared with the yield in 2 grains seeding as $10,200kg{\cdot}ha^{-1}$.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.21-26
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• 2011

Differences among cultivars, conditions of nutrient solution, nursing materials, and soilless culture systems were investigated to select suitable cultivar and cultivation methods for stable production of summer spinach in the highlands. The 'Quinto' spinach showed the earliest growth and highest yield. For yield increase of summer spinach, optimal solution pH was 6.0, EC was $2.0dS{\cdot}m^{-1}$, and $NH_4-N$ ratio of nutrient solution was 30 percent Stand rate of spinach in nursing seedlings, at 200-cell-tray filled with mixed nursing soil (peat : perlite = 7 : 3), was higher than those grown in urethane sponge and rock-wool plug. Yield was also 18 to 24 percent higher than those in rock-wool plug and urethane sponge. Plant length and yield of spinach in mixed substrate (peat : perlite = 7 : 3) filled nutrient film technique (MSNFT) system were longer of 18 percent, and higher of 9 percent than those in deep flow technique (DFT) system, respectively. However, changes of root zone temperature, pH and EC showed similar pattern with DFT. Therefore, growing 'Quinto' cultivar at 6.0 of pH, $2.0dS{\cdot}m^{-1}$ of EC, 30 percent of $NH_4-N$ ratio, at 200-cell-tray filled with mixed nursing soil, and MSNFT cultivation system, was the best for production of summer spinach in the highlands.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.580-584
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• 2010

The effect of planting densities on the growth of $Sedum$ $samentosum$ (4 collections) was investigated using nutrient film technique (NFT) with Yamazaki' lettuce nutrient solution (1982) from September 5th to October 24th in non-heating plastic film house. At 40 days, the plant height of 4 collections showed the range of 15.0-18.9 cm, and mean plant height was high the order of $10{\times}10$, $2.5{\times}2.5$, and $5{\times}5cm$. The growth of 'Pohang' and 'Wando' collections was better compared to that of 'Gunsan' and 'Wanju' collections. Number of node, stem diameter, and fresh and dry weight per plant were decreased in higher planting density. Despite the lower fresh weight per plant obtained, the fresh yield per $m^2$ was significantly increased in higher planting density. The mean fresh yield was $14.9kg{\cdot}m^{-2}$ in $2.5{\times}2.5cm$, and 'Pohang' collection showed the highest fresh yield ($17.6kg{\cdot}m^{-2}$). The first optimized harvesting time base on plant height was 30-40 days after NFT culture during autumn season. In eating quality, compression force of stem and bitterness of shoot were decreased in higher planting density. However, the heavy labor demanding high density cutting needs to be improved for hydroponic culture of $S.$ $samentosum$.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.493-498
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• 2014

The objective of this study was to make growth and yield models for common ice plant (Mesembryanthemum crystallinum L.) using expolinear functional equations in a closed-type plant production system. Three-band radiation type fluorescent lamps with a 12-hours photoperiod were used, and the light intensity was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Nutrient film systems with three layers were used for plant growth. Environmental conditions, such as air temperature, relative humidity and $CO_2$ concentration were controlled by an ON/OFF operation. Leaf area, shoot fresh and dry weights, light use efficiency of common ice plant as function of days after transplanting, accumulative temperature and accumulative radiation were analyzed. Leaf area, shoot fresh and dry weights per area were described using an expolinear equation. A linear relationship between shoot dry and fresh weights was observed. Light use efficiency of common ice plant was $3.3g{\cdot}MJ^{-1}$ at 30 days after transplanting. It is concluded that the expolinear growth model can be a useful tool for quantifying the growth and yield of common ice plant in a closed plant production system.