• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.593-598
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• 2010

The optimum condition for fluoride removal, water content reduction, and $CaF_2$ purity was determined in treating semiconductor waste water in which ammonia nitrogen, phosphorus, and fluoride are existed simultaneously using a fluidized bed reactor. Effects of pH, seed dosage, and recirculation of treated water were investigated through lab-scale experiments. Considering fluoride removal, sludge purity, and water content, that pH 5 and seed dose of 150 g were found to be optimum. Correspondingly, removal of fluoride and phosphate (${PO_4}^{3-}$-P) was 94.24% and 8.97%, respectively, with water content ratio of 12.94%. Increase in an amount of seed dosage not only enhance fluoride removal efficiency, but also buffer fluoride removal-reducing effect due to the variation of recirculation ratio of treated water and pH.

• ALGAE
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• v.22 no.2
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• pp.141-146
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• 2007

Seagrass bed is an important component in coastal and estuarine ecosystems, providing food and habitats to a wide variety of marine organisms. Recently, seagrass coverage has declined significantly due to anthropogenic impacts such as cultural eutrophication and reclamation, and thus efforts are under way to prevent further losses and restore disturbed seagrass habitats worldwide. Seagrass transplantation techniques for habitat restoration include vegetative and seed-based methods. Seagrass seeds can be collected easily, and sowing seeds is an economically effective method for large-scale restoration. However, large numbers of seed can be lost by seed predation and physical disturbance in the planting areas. In the present study, Zostera marina seeds were coated with loess to reduce seed loss by predation and sweeping away by the water currents, and germination rates of coated seeds and seedling growth were examined to assess the feasibility of the seed-coating method for large-scale restoration. Germination rate of the coated seeds with loess was significantly higher than that of the uncoated seeds. Additionally, seedling growths were not significantly different between the coated and the uncoated seeds. These results suggest that coating of eelgrass seeds with loess enhances success of seed germintion with no harmful effects on seedling growth. Therefore, the seed coating method using loess may be an effective and applicable seedbased transplanting technique for large-scale restoration.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.50-50
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• 2017

Swampland is a potential alternative land to be used in various agricultural production activities in Indonesia, because Indonesia have 33.41 million hectares of swamp land that consists of 13.28 million hectares nontidal swamp and million hectares 20.13 tidal swamp. In the province of South Sumatra, because of unpredictable water level in the field before planting, farmers have been doing agronomic adaptation method through the delay time of transplanting and forced to apply more than one the nursery practice with the combination of a floating nursery method and a dry-bed nursery method. This study was aimed to (1) evaluate the seedling growth and tillering pattern of several popular Indonesian rice varieties, and (2) look for alternative technologies to get a better rice seedlings under two nursery methods in the nontidal swamp land. In the first experiment, the seedling growth characteristics of five rice varieties (Ciherang, Inpara 5, Inpara 9, Inpari 29, and Inpari 30) was evaluated by two methods of nursery, i.e. floating nursery and dry-bed nursery. In the second experiment, rice variety of Inpari 30 was treated with Zn seed priming and foliar fertilizer of 2,300 ppm N at the nursery stage. Those treatments were combined with the time of seedling under floating and dry-bed nursery. The results of the first experiment showed that of the five varieties tested, dry-bed nursery method showed better seedling growth than floating nursery. This was indicated by high leaf number, tiller number, tillers pattern, shoot-root ratio and relative growth rate. Ciherang and Inpari 30 showed high tiller number, and they had produced tertiary tiller in the sixth week of observation. Moreover, shorter period of floating and dry-bed nursery in combination with the treatment of Zn seed priming and spraying seedling with foliar fertilizer N could improve the growth of seedlings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.54-58
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• 1988

To define natural embryo growth and germination of the Korean ginseng (Panax ginseng C.A.Meyer) seed, freshly harvested and depulped seeds were seeded on nursery bed at Aug. 5 without stratification. At 100 days after seeding, embryo/endosperm length ratio of the seeds in nursery bed was higher than that of the seeds which were stratified with conventional method for 100 days. And also there was no significant difference between dehiscence ratio of the seeds in nursery bed and that from stratification with sand. The germination ratio of the ginseng seeds seeded without stratification at Aug. 5 was about 57% in average of 2 years and was not significantly lower than that of the seeds seeded after stratification at Nov. 15. And there were also no significant differencies of plant growth after germination between the ginseng seedlings from two seeding methods.

• Journal of Plant Biology
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• v.13 no.4
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• pp.13-22
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• 1970

The rice variety, Kwanok, was reared in the water, land and salt seed beds and transplanted to the reclaimed soil area having an average of 0.48% salt content (0.67% at the end of April). The plant height of land bel seedlings at transplanting stage was short but the dry-weight/plant-height ratio was large and the rooting ability was vigorous remarkably after transplantation in the salty area. The central cylinder, vessels, sclerenchyma, endodermis and other mechanical tissues of the root of land bed seedlings were well developed while the size of cortical cell layers were small. The cytoplasm of the cortical parenchyma at the root tips seemed to be most abundant in the land bed seedlings. The formation of the aerial cavity in the cortex of primary root was rapid and it seemed that the developmental mechanism of the aerial cavity in the rice plant roots was related to the development of the lateral roots.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.05a
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• pp.122-123
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• 2001

• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.259-270
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• 1998

An automatic seedling transplanter, employed an innovative plug-seedling feeder was developed by improving the problems of conversational feeding and transplanting mechanisms. With conventional methods, missing and damage rates of seedling were high for long seedlings over 20cm and also breaking seed-bed was frequently observed. Thus, a pushout-bucket slide-hopper type trandsplanter was devised and tested. Test results of picking and transferring accuracies of the developed transplanter are as follows : A prototype transplanter performed with 1.5% of missing rate. The deviations of horizontal feed ranged from -0.3mm to 2.8mm and averaged 0.673mm for the 128-hoe test tray : and ranged from -lmm to ＋3mm and averaged 0.785mm for the 200-hole test tray. The deviations could decrease with precise manufacturing and lightening the mechanism. The maximum and deviations of vertical feed were -2.3mm and + 1mm, respectively, for the 128-hole test tray ; and were ＋3mm and ＋2.5mm, respectively, for the 200-hole test tray. The missing rate, seeding bruise rate and seed-bed damage rate were esitmate to be 1.3％, 0.4% and 3.5％, respectively, with the developed automatic transplanter.

• Environmental Engineering Research
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• v.11 no.4
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• pp.173-180
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• 2006

Autotrophic nitrogen removal and its microbial community from a laboratory scale upflow anaerobic sludge bed reactor were characterized with dynamic behavior of nitrogen removal and sequencing result of molecular technique (DNA extraction, PCR and amplification of 16S rDNA), respectively. In the experiment treating inorganic wastewater, the anaerobic granular sludge from a full-scale UASB reactor treating industrial wastewater was inoculated as seed biomass. The operating results revealed that an addition of hydroxylamine would result in lithoautotrophic ammonium oxidation to nitrite/nitrate, and also hydrazine would play an important role for the success of sustainable nitrogen removal process. Total N and ammonium removal of 48% and 92% was observed, corresponding to nitrogen conversion of 0.023 g N/L-d. The reddish brown-colored granular sludge with a diameter of $1{\sim}2\;mm$ was observed at the lower part of sludge bed. The microbial characterization suggests that an anoxic ammonium oxidizer and an anoxic denitrifying autotrophic nitrifier contribute mainly to the nitrogen removal in the reactor. The results revealed the feasibility on development of high performance lithoautotrophic nitrogen removal process with its microbial granulation.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.414-420
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• 1988

This research was performed to estimate the degree of influence of relative light intensity and planting density on the weight growth in the trans-planting bed. The Piuns koraionsis seedlings treated for different degrees of shading on seed bed were planted in transplanting bed. 1. The seedling weight growth under 100% relative light intensity and $6{\times}6$ plot(36 individual) density showed the largest growth and the best growth was found during 26th of May 25 of June. 2. As the relative light intensity decrease and with planting density increased, the weight growth decreased. And the weight growth had a tendency to decrease after 26th of May-25th of June. 3. T/R ratio showed the highest value under 63% relative light intensity and $12{\times}12$ plot (224 individual) of planting density. The highest T/R ratio was found during 26th of July-25th August.

• Journal of Forest and Environmental Science
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• v.38 no.1
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• pp.38-47
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• 2022

Hymenodictyon orixensis (Roxb.) Mabberley (locally known as Bhutum in Bangladesh) is both an ecologically and economically valuable multipurpose tree species for afforestation and reforestation programs in Bangladesh. Seed germination and seedling development study of H. orixense were conducted to find out the response to different growing medium, e.g., polybag (15×10 cm (T₀) and 20×15 cm (T₁)), sand medium in propagator house (T₂), conventional nursery bed (T₃), and root trainer (T₄) in the Nursery. Consequently, germination behavior and seedling morphological parameters of H. orixense were assessed. The results revealed that the sand medium of the propagator house (T₂) provided the highest germination % (58.57±22.30) and the highest germination energy (11.43±2.43) followed by seedlings growing in 20×15 cm polybags (T1) containing forest topsoil and cow-dung at a ratio of 3:1. Except for germination energy, germination values, and germination capacity, other seed biology parameters, particularly imbibition, germination period, germination rate, and plant survival percent in T₁, T₂, T₃, and T₄ were significantly (p<0.05) different from T₀. Each phenotypic parameter of seedlings and dry matter of shoot and root significantly differed from control except root length (p<0.992). Based on this study, Polybags of 20×15 cm size are regarded as the best medium for quality seedling development of H. orixense. The nursery bed (T₃) had the lowest germination performance and developed more inferior quality seedlings. Thereby, 20×15 cm size of polybags with conventional soil and cow-dung media is recommended for maximum germination and to grow the quality seedlings of H. orixense in the Nursery.