• Journal of Wetlands Research
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• v.15 no.4
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• pp.555-566
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• 2013

Total maximum daily load enforced in 2004 is a program to evaluate the amount of pollutants by each land use type and manage to meet a target water quality of each waterbody. The many research to calculate runoff load of pollutants by landuse type have been studied. This study was conducted to calculate pollutants EMC, load and unit load in stormwater runoff generated from tomato growing area. Monitoring was conducted about 32 event during 4years and water quality parameters such as BOD, $COD_{Mn}$, TOC, TSS, TN, TP, $NH_3-N$, $NO_3-N$, $PO_4-P$ were analyzed at the laboratory. The average EMC were measured as follows: 9.6 BOD mg/L, 17.2 $COD_{Mn}$ mg/L, 5.5 TOC mg/L, 319.4 TSS mg/L, 4.4 T-N mg/L, 2.6 T-P mg/L, 0.5 $NH_3-N$ mg/L, 0.04 $NO_2-N$ mg/L, 2.6 $NO_3-N$ mg/L, 0.8 $PO_4-P$ mg/L. TN and TP is dichargeed as $NO_3-N$ and particle phosphorus type, respectively.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.93-100
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• 2011

Maintenance of adequate soil water potential during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement within and below the rooting zone can facilitate optimal irrigation scheduling aimed at minimizing the adverse effects of water stress on crop growth and development and the leaching of water below the root zone which can have adverse environmental effects. The objective of this study was to evaluate the feasibility of using a portable irrigation controller with an Watermark sensor for the cultivation of drip-irrigated vegetable crops in a greenhouse. The control capability of the irrigation controller for a soil water potential of -20 kPa was evaluated under summer conditions by cultivating 45-day-old tomato plants grown in three differently textured soils (sandy loam, loam, and loamy sands). Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30 cm depths. Even though a repeatable cycling of soil water potential occurred for the potential treatment, the lower limit of the Watermark (about 0 kPa) obtained in this study presented a limitation of using the Watermark sensor for optimal irrigation of tomato plants where -20 kPa was used as a point for triggering irrigations. This problem might be related to the slow response time and inadequate soil-sensor interface of the Watermark sensor as compared to a porous and ceramic cup-based tensiometer with a sensitive pressure transducer. In addition, the irrigation time of 50 to 60 min at each of the irrigation operation gave a rapid drop of the potential to zero, resulting in over irrigation of tomatoes. There were differences in water content among the three different soil types under the variable rate irrigation, showing a range of water contents of 16 to 24%, 17 to 28%, and 24 to 32% for loamy sand, sandy loam, and loam soils, respectively. The greatest rate increase in water content was observed in the top of 10 cm depth of sandy loam soil within almost 60 min from the start of irrigation.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.7-13
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• 2006

Plastichouse cultivation for crops and vegetables in the winter has been widely popularized in Korea. In the vinylhouse Ultraviolet B penetration is lower than in the field, and so some problems, as plant overgrowth and outbreak of disease, occurred frequently. The effect of artificial supplement ultraviolet B $(UV-B:280{\sim}320nm)$ radiation on the physiological responses and yield of perilla (perilla frutescens) was investigated UV-B ray was radiated on perilla with the 10th leaf stage at the distance of 90, 120 and 150 cm from the plant canopy for 30 days after planting in the vinylhouse. The production of fresh perilla leaves was high in the order of plastic house, ambient+50% of supplemental UV-B, ambient ambient+100% of supplemental UV-B. Enhanced UV-B radiation affected the intensity of thirty-three proteins in 2-dimensional electrophoretic analysis of proteins and ten proteins out of them seemed to be responsive to UV-B : a protein was, ATP synthase CF1 alpha chain, down regulated and nine proteins (Chlorophyll a/b bindng protein type I, Chlorophyll a/b binding protein type II precursor, Photosystem I P700 chlorophyll a apoprotein A2, DNA recombination and repair protein recF, Galactinol synthase, S-adenosyl-L-methionine, Heat shock protein 21, Calcium-dependent protein kinase(CDPK)-like, Catalase) were up-regulated.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.248-255
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• 2011

For the environmental friendly soil management on the cultivation of crops in the greenhouse, organic materials, such as the by product-fertilizer derived from livestock manure, rice straw, mushroom media, rice hulls, wood sawdust, and cocopeat, were used as carbon sources adjusting the ratio of carbon to nitrogen to 10, 20, and 30 based on the inorganic soil N. In each C/N ratio of greenhouse soil, watermelon was cultivated in the greenhouse as crop for experiment for the spring and summer of the year and the experimental results were summarized as follows. The concentration of T-C in the organic materials applied were between $289{\sim}429g\;kg^{-1}$, In the C/N ratio of 10, using watermelon as the crop cultivated during the second half of the year in the greenhouse soil, the $NO_3$-N and EC were reduced by 21 to 37%, and 26 to 33%, respectively, except the by product-fertilizer from livestock manure, compared to the soil $NO_3$-N and EC used in the experiment. After the watermelon was cultivated in soils that C/N ratios were controlled as 10, 20, and 30 with wood sawdust adding as carbon sources in the three soils with the different EC values, EC values of the soils were reduced by 33, 42, and 39%, respectively, compared to the soil EC used in the experiment. The weight of watermelon was 10.1-13.4 kg per one unit, and, of the three soils with different EC values. In the soils with three different EC values controlled at C/N ratio of 20, the weight of watermelon was good. The degree of sugar of watermelon were 11.8 to 12.3 Brix, which means that the difference between the treatments was not significant. In conclusion, the C/N ratio of 20 controlled by the proper supply of organic materials according to the representative EC values shown in the greenhouse soils was optimal condition enough to maintain the soil management for the organic culture with the proper nutrient cycling.

• Korean Journal of Environment and Ecology
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• v.28 no.4
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• pp.457-471
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• 2014

This study aims to present an evaluation scheme to improve the problems in tree shapes and tree growth which were identified through shape and growth assessments of landscape trees currently planted in Haedoji Park, Songdo, Incheon Metropolitan City after plant structure status and propriety review for funtion of space and concept of planting. Suitability the planting concept was evaluated according to function of space. The result indicated that the shade planting areas accounted for 29.5% of the the shade spaces area. 58.7%, respectively planting areas of visual landscape. And 11.8%, respectively planting areas of buffer. Because the planting areas was lacked according to the park established spatial configuration of central facilities and the result of plant young trees. Plant structure status required consideration with plant structure, density, size, growth status for improve planting function. The tree assessment was performed on a total of 28 species and 600 trees of which 22 species and 209 trees were planted in the buffer zone, 8 species and 71 trees in the shade zone, 16 species and 266 trees in the visual landscape zone, and 4 species and 54 trees in the ecological landscape zone. The trees were divided into grades based on their assessment score and were statistically grouped by the functional zone in where they are planted and by tree species to verify their significance. The tree shape assessment was an average of 56.6 points and the tree growth assessment was an average of 76.0 points. Using the results of the tree assessments, the tree standards for each functional space were identified and a concept of optimum planting and cultivating was applied. When applying the shape assessment results by zone to the concept of planting, since trees for buffering require high functionality they received E's, the lowest grade; as trees for ecological landscaping require diverseness and naturalness, they received D's; since trees for shading require utilization, they received C's as trees with branching at the main stems were considered; and since trees for visual landscaping required aesthetical value, they received A's and B's. When applying the growth assessment results by zone to the concept of planting, based on planting foundations of favorable and poor, for buffering, visual landscaping, and ecological landscaping, trees from grades A to E could be planted, and for shading, trees from grades A to C could be planted. For a cultivation plan that could improve the growth of the trees, we proposed that the topography of the land be selected considering the tree's characteristics and that a method of pot seeding be used. Also, to improve the shape of the trees, we proposed that poles be used to improve the growth of vertically-straight stems, an appropriate planting density be applied for reasonable branch growth, manage tree shape to maintain good crowning, and better manage fertilization to maintain a reasonable crown density.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.22-28
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• 2005

The use of blankets to preserve heat in oriental melon cultivation is a common practise without artificial heating and warming systems. Efficiency of blanket decreased with annually usage. This experiment was conducted to investigate the effect of double layer nonwoven fabrics on heat conservation, plant growth, fruit quality and yield of oriental melon in greenhouse. The results were compared among the non-woven fabrics of 9+3, 6+6, 6+3 and 12 ounce from transplanting to April 20, 2001, 2002. Night temperature within tunnel was high at 9+3, 6+6, 6+3 and 12 ounce in order. In plant growth, stem length, leaf numbers and exudate, under double layer nonwoven fabrics were better than single layer blanket of 12 ounce especially, 9+3 double layer blanket was the best. Fruit weight, flesh thickness, soluble solid and marketable yield rate remained same in all treatments. Fermented fruit rate was the highest in 12 ounce as $32.9\%,\;19.6\%\;under\;9+3,\;17.1\%\;under\;6+6,\;16.6\%$ under 6+3 double layer nonwoven fabric, respectively. Compared to 2,260kg yield per 10a of 12 ounce single layer nonwoven fabrics, $7\%$ was increased under 9+3 but $3\%\;and\;13\%$ were decreased under 6+6 and 6+3 double layer nonwoven fabrics, respectively. Compared to income, 4,499-thousand-won per 10a, of 12 ounce single layer blanket, $13\%\;and\;3$ were increased under 9+3 and 6+6 double layer nonwoven fabrics, respectively. Whereas, $10\%$ decreased under 6+3 double layer nonwoven fabrics. From this results it is evident that 9+3 double layer nonwoven fabrics was the best for thermokeeping, fruit quality, and was most economic under non heating system.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.31-35
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• 2010

In this experiment, the effects on the growth and the quality of cut flowers of chrysanthemum 'Jinba' were mainly concerned depending on cultural methods between the pinching and the non-pinching. According to the results, the sufficient period of the vegetative growth was necessary to enter the flower bud differentiation in case of the non-pinching cultivation whereas it was not the case on the pinching. As compared with the pinching, the non-pinching showed 10% higher in the flowering ratio after flower bud differentiation. The flowering ratio of the non-pinching exceeded more than 95% but the pinching showed below 95% of the flowering ratio after flower bud differentiation. Comparing the number of cutting flowers between pinching and non-pinching, it was the non-pinching that showed the production of the first grade cutting flowers about 5 weeks faster than that of the pinching. It seem to be possible that harvesting time and growing period could be shortened. In the non-pinching growing region, above third-grading marketable cut flowers was 100% regardless of planting time. On the contrary, the pinching method showed 84.7% of marketable cutting flowers at first week from the planting, followed by 64.3% at second week, 18.8% at third week, and 2.6% at fourth week. Marketability of cutting flowers indicates that were planted by the pinching is very poor. When draw a comparison between the fourth-week planting of the non-pinching with the first-week planting of the pinching, the non-pinching could cut the growing period 38 days shorter than the pinching and the marketability was better. These results indicate that the non-pinching method can shorten the growing period and harvesting time compared to the pinching and it also resulted in reduction of cost and rapid production of the cutting flowers.

• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.35-42
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• 2017

This research was conducted to investigate the influence of post-planting fertilizer concentrations on the growth of seedlings and changes of nutrient concentrations of media in tomato seedling production through sub-irrigation. Two root media such as peat moss (grade of 0 to 6 mm, PM06) plus perlite (grade of 1 to 2 mm (PE2)(7:3, v/v) and peat moss (grade of 5 to 15 mm, PM515) plus PE2 (7:3, v/v) were formulated and filled into 72-cell plug trays. After seeds of 'Dotaerang Dia' tomato were sown and germinated at $28^{\circ}C$, the trays were moved to greenhouse and seedlings were raised 35 days. When the cotyledons were emerged, post-planting fertilizers of 13-2-13, 15-0-15 and 20-9-20 ($N-P_2O_5-K_2O$) were applied in a sequence. The fertilizer concentrations based on N in each plug stage were differed with $25mg{\cdot}L^{-1}$ in three treatments. The fertilizer solutions were supplied when the weight of plug trays decreased to 40 to 50% compared to container capacity. The root media were collected in 1, 2, 4, and 5 weeks after sowing and were divided into top, middle, and bottom parts, then were analysed for pH, EC and macro-nutrient concentrations. The seedling growth was investigated 5 weeks after sowing. The pH and EC in PM06+PE2 was higher than those of PM515+PE2. The bottom and mid-part had higher pH and lower EC compared to upper part in each medium. The differences of EC between upper and bottom parts were around 2 times in each medium. The $NH_4-N$ and K concentrations in program 3 of PM06+PE2 showed the highest concentrations among all treatments. The $NO_3-N$ concentrations in PM06+PE2 increased gradually and this rising tendency become severe as post-planting fertilizer concentrations were elevated. The seedling growth in terms of fresh and dry weights was the highest in the treatment of program 2 in PM06+PE2 among all treatments tested. Above results indicate that the gradual increases of fertilizer concentrations from 25 to $125mg{\cdot}L^{-1}$ in plug stages 2, 3, and 4 plug stages are desirable for

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.296-300
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• 2015

This study was conducted to investigate optimal crop loads of 'Jinok' grape for unheated plastic house culture. The crop loads of 'Jinok' grapes were managed to be 1.3, 1.8, 2.2, 2.4, and 2.6t per 10a from 2012 to 2014. We measured vine growth and berry qualities. Crop loads were not significantly affected on plant height, trunk diameter, shoot length, and the internode length of 'Jinok'. However, the maturation of berries was delayed when the crop load was higher. And the harvest date was earlier about three weeks in an unheated plastic house compared to in an open field. The average berry weight was decreased by the higher crop load although higher crop loads made higher yields showing the lowest weight at 342g with the treatment of 2.6t per 10a and the highest weight at 363g with the treatment of 1.3t per 10a. Also, the soluble solids content showed a tendency that higher crop loads brought to lower degree Brix. The contents of P, K, Ca, and Mg in grape leaves and shoots were not significantly different by crop loads. To sum up, when crop loads were under the 2.4t per 10a, the berries were harvested as a marketable fruit having $15^{\circ}Brix$ in the cultivar 'Jinok' grape. This result could help to increase grower's benefit having improved quality of fruit for the sustainable production by the established cultivation techniques for the newly developed cultivar 'Jinok'.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.238-243
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• 2009

To investigate the characteristics of moisture content (MC), moisture distribution and starting point of drainage in a rockwool slab culture, time domain reflectometry (TDR) sensors were used in a drip irrigation system. MC values ($0{\sim}100%$) measured by TDR sensors in a slab were compared to those by loadcells. Seventy two seedlings of paprika (Capsicum annuum L.) were cultured for $5{\sim}6$ months in a green-house and the starting point of irrigation was determined by the average value of three TDR sensors which were inserted diagonally across the slabs under the plants. MCs as a standard for starting point of irrigation by TDR were determined with 40%, 50%, and 60%. Distribution of MCs in a slab measured with five TDR sensors equally spaced from two irrigation points were not much different when the MC in the slab increased from zero to saturation point. The saturated MCs in the slab were presented at $58{\sim}65%$ and the drain was started when the MC became around $50{\sim}55%$. At the saturated MC in the slab, TDR sensors presented 100% but the values from the loadcell showed 90% at the same time. However, measurement errors between two methods for MC remarkably decreased with a decrease in the MC in a slab. Especially when the MC was maintaining below 60%, the errors between TDR and loadcell methods for measuring MC in the rock-wool slab were less than 5%. There were no significant differences in number of fruits and fresh and dry weights of fruits when they were cultured under the different MC conditions with three irrigation regimes (40%, 50%, and 60%). These results indicated that the MC control by TDR sensors in a rock-wool based paprika culture can be suggested as a method to determine the starting point of irrigation for a soilless culture system.