• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.33-36
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• 2008

This paper presents soil moisture retrieval from measured polarimetric backscattering coefficients of a vegetated surface. Based on the analysis of the quite complicate first-order radiative transfer scattering model for vegetated surfaces, a simplified scattering model is proposed for an inversion algorithm. Extraction of the surface-scatter component from the total scattering of a vegetation canopy is addressed using the simplified model, and also using the three-component decomposition technique. The backscattering coefficients are measured with a polarimetric L-band scatterometer during two months. At the same time, the biomasses, leaf moisture contents, and soil moisture contents are also measured. Then the measurement data are used to estimate the model parameters for vv-, hh-, and vh-polarizations. The scattering model for tall-grass-covered surfaces is inverted to retrieve the soil moisture content from the measurements using a genetic algorithm. The retrieved soil moisture contents agree quite well with the in-situ measured soil moisture data.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.3
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• pp.404-412
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• 2005

The surface energy budget depends on many factors, such as the type of surface, the soil moisture and the vegetation canopy, the geographical location, daily, monthly and seasonal variations, and weather conditions. In the coastal region, the surface is not homogeneous at various scales for instance water, sand, mud, tall grass, and crops. The energy balance over the vegetation canopy was analyzed with the optical energy balance measuring system. The latent heat flux was more intensive than the sensible heat flux. The sensible heat flux was very small in summer due to the canopy effect and higher in spring and autumn. In summer the development of the atmospheric boundary depended on rather the vertical shear of wind than the sensible heat flux.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.101-110
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• 2010

This study was performed to evaluate the void ratio and strength of porous polymer concrete used coarse aggregates and unsaturated polyester resin to find optimum mix design of porous polymer concrete for planting block. Also, this study was performed to evaluate the planting properties of herbaceous plant and cool-season grass in porous polymer blocks based on the experimental results of porous polymer concrete to develop environmentally friendly planting blocks. Tests for the void ratio and compressive strength of porous polymer concrete were performed at the curing age 7 days. Also, kinds of plants such as Tall fescue, Perennial ryegrass, Lespedeza and Alfalfa for planting were applied to porous polymer blocks. Within 6 weeks after seed, initial germination ratio, cover view and growth length for planting blocks were estimated by various methods.

• Korean Journal of Remote Sensing
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• v.24 no.5
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• pp.427-436
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• 2008

This paper presents radar remote sensing of soil moisture and surface roughness for vegetated surfaces. A precise volume scattering model for a vegetated surface is derived based on the first-order radiative transfer technique. At first, the scattering mechanisms of the scattering model are analyzed for various conditions of the vegetation canopies. Then, the scattering model is simplified step by step for developing an appropriate inversion algorithm. For verifying the scattering model and the inversion algorithm, the polarimetric backscattering coefficients at 1.85 GHz, as well as the ground truth data, of a tall-grass field are measured for various soil moisture conditions. The genetic algorithm is employed in the inversion algorithm for retrieving soil moisture and surface roughness from the radar measurements. It is found that the scattering model agrees quite well with the measurements. It is also found that the retrieved soil moisture and surface roughness parameters agree well with the field-measured ground truth data.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.317-324
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• 2010

Recently, fallow paddy land located in the mid-mountain area (FPL) due to a decrease in rice consumption has increased in some regions of our country. So, grasses and forage crops available for years in once sowing should be introduced in FPL. This study was conducted to develop the technique for cultivation of grasses and forage crops using animal manure in FPL The field experiments were carried out from 2007 to 2009 on FPL at Kumsan, Chungbuk province in Korea. Cattle feedlot manure (CFM) was prepared by mixing feces and urine of cattle with rice straw in cattle feedlot for 6 months. The experimental plots were consisted of four treatments; tall fescue-based mixed pasture applied with chemical fertilizer (Control), mono-tall fescue pasture (MTFP), tall fescue-based mixed pasture (TFBMP), mono-Perennial ryegrass (MPR-FCM), mono-Italian ryegrass (MIR-FCM), mono-Red clover (MRC-FCM) and mono-Reed canarygrass (MRCG-FCM) applied with FCM. The field of tall fescue-based pasture had been sown with a grasses mixture containing 'Fawn' tall fescue, 'potomac' orchardgrass, 'Reveille' Perennial ryegrass, and 'kenblue' Kentuky bluegrass, 'Kenland' Red clover. Seeding rates were 16, 6, 4, 2 and $2\;ha^{-1}$, respectively. DM yields of forages and rates of grass coverage was higher in MTFP, TFBMP and MRCG-FCM as compated with control treatment. This result means that FPL has contained with favorable conditions for growing grass, because forage productivity is more than 15 tons per ha per year in fallow paddy land. In addition, the farmer can save the trouble of repeated plowing and sowing every year, due to the introduction of perennial grasses. The farmer must conduct the re-seeding and induce the improvement of management methods for the elevation of the persistence of red clover and perennial ryegrass, because both red clover and perennial ryegrass having high nutritive value and palatability was less persistent. Therefore, we suggest that FPL may be the good land for forage production utilizing FCM and FCM can be applied on FPL without any negative effects on DM production and the property of soil. FPL of Korea can be better utilized by applying FCM to the mono and/or mixed swards.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.411-418
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• 2012

This study was conducted to develop the technique for cultivation of forage crops using swine slurry in fallow paddy land located in the mid-mountain area (FPL). The field experiments were carried out from 2007 to 2009 on FPL at Kumsan, Chungbuk province in Korea. Swine slurry was prepared which decayed for 6 months. The experimental plots were consisted of seven treatments; tall fescue-based mixed pasture applied with chemical fertilizer (Control), mono-tall fescue pasture (MTF), tall fescue-based mixed pasture (TFBM), mono-Perennial ryegrass (MPR), mono-Italian ryegrass (MIR), mono-Red clover (MRC and mono), Reed canarygrass (MRCG) applied with swine slurry. The field of tall fescue-based pasture had been sown with a grasses mixture containing 'Fawn' tall fescue, 'potomac' orchardgrass, 'Reveille' Perennial ryegrass, and 'kenblue' Kentuky bluegrass, 'Kenland' Red clover. Seeding rates were 16, 6, 4, 2 and 2 (kg) per ha, respectively. DM yields of forages and rates of grass coverage were higher in MTF, TFBM and MRCG as compared with control treatment. This result means that FPL has contained with favorable conditions for growing grass, because forage productivity is more than 14.5 tons per ha per year in fallow paddy land. In addition, the farmer can save the trouble of repeated plowing and sowing every year, with the introduction of perennial grasses. The farmer must conduct the re-seeding and induce the improvement of management methods for the elevation of the persistence of red clover and perennial ryegrass, because both red clover and perennial ryegrass having high nutritive value and palatability was less persistent. Therefore, we suggest that FPL may be the good land for forage production utilizing swine slurry and swine slurry can be applied on FPL without any negative effects on DM production and the property of soil. FPL of Korea can be better utilized by applying swine slurry to the mono and/or mixed swards.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.231-238
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• 1986

This field experiment was undertaken to assess the effects of three levels of inclination ($10^{\circ}$, $20^{\circ}$ and $30^{\circ}$) and four rates of $N-P_2O_5-K_2O$ (0-0-0, 14-10-10, 28-25-25, and 42-40-40 kg/10a) on the hilly pasture concerning to establishment, forage yield and quality, and botanical composition in the mixed grass-clover sward set up on a new reclaimed woodland by an oversowing method. This part was concerned with the concentration and mutual balance of mineral nutrients in relation to grass tetany hazard. The results obtained were summarized as follows: 1. Concentration of exchangeable Mg, relative proportions of Mg to CEC, K, and Ca in soil were considerably below the critical level for good forage growth and prevention of grass tetany. These properties were rather worsened by increasing the inclination grade and the NPK rate. 2. Compared with the critical level for the likelihood of tetany (Mg < 0.2%, K > 2.5%, and K/(Ca+Mg) equivalent ratio > 2.2 in forages in DM basis), mean concentration of Mg in mixed forages turned out to range from 0.09 to 0.14%. 2.6% of K concentration and 2.5 of K/(Ca+Mg) equivalent ratio were shown to be at a normal NPK rate. The likelihood of grass tetany was generally enhanced by increasing the inclination grade and the NPK rate. 3. The increasing of the inclination grade and NPK rate rather aggravated the low Mg concentration and unbalanced mutual ratios of mineral nutrients, from which resulted the grass tetany hazard and the depression of forage growth. To prevent these two resulted factors, Mg fertilization on grassland and/or extra Mg supplement to dairy cattle needed to be carried out. 4. The Ca/P ratios in the mixed forages ranging from 1.0 to 2.0 were reduced by the increased rate of NPK, whereas the difference due to inclination grade was yet to be recognized.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.163-176
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• 2009

Investigating endophyte distribution, naturally occurring in native grasses, is important for understanding endophyte-grass associations and using the beneficial effects of endophytes in cultivated plants. The goal of this study was to investigate endophytes from natural Festuca spp. in Yunnan, Guizhou, and Sichuan Provinces of China, and to study the compatibility between the endophytes and turf type tall fescue (Festuca arundinacea) which is widely used for lawn and athletic fields in that region. Of 628 accessions in F. ovina, 421 had endophytes identified in leaf sheath from on-site microscopic examination. From Festuca spp, three isolates were obtained from the seeds and ninety isolates were obtained from seedlings established from the collected seeds. The isolates from F. ovina and F. stapfii were tentatively identified as Neotyphodium typhinum and Neotyphodiumstarii, respectively. We tested compatibility of the two fungal species with seven tall fescue cultivars, Little Hero, Sub Boy, Eldorado, Arid III, Millennium, Crossfire, and Fawn. N. typhinum or N. starii did not infect 'Fawn' with either seed injection or seed soaking method. The highest infection rate byboth N. typhinum and N. starii was in 'Sun Boy' and 'Eldorado'. There were significant interaction effects between tall fescue cultivar and type of endophyte on infection.

• Korean Journal of Agricultural Science
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• v.3 no.2
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• pp.184-191
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• 1976

This experiment was conducted for the control of summer depression of cool-season pasture plant. Orchard grass, tall fescue, red clover, alfalfa, and crabgrass were mulched by barley straw with depths of $100g/m^2$, $200g/m^2$ and $300g/m^2$ for 45 days -from July 1, to August 14-, and the effects on growth, yield and chemical composition were observed. The results obetain were as follow: Temperature decrease of $1.0{\sim}3.04^{\circ}C$ was followed after barley straw mulching on the grassland as compared with the control. The growth of the grasses after mulching was hastened, i. e. plant height was increasd 6.0~45% as compared with the control. Barley straw mulching with $100g/m^2$ supported the increase in yield of the grasses with an average of 32.77%, however, average yield was decreased by 7.75% with $300g/m^2$ mulching, apparently due to the rottening of grasses. Chemical compositions of mulched grasses were varied; contents of crude protein and nitrogen free extract were higher, but crude fats, fibre, and ashes were lower than those of the control.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.281-286
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• 2007

Surface sowing method is one of the important methods to establish seeds in mountainous area. Seed-coating technique in the surface sowing method is increasing interest in the world today. An experiment was conducted to develope a technique for pelleting seeds of grass in woodland. Results showed that the seed pelleting was a useful technique than coating seeds because the pelleting reduced coating time and increased amounts of coated seeds per hour. As lowering temperature and reducing time for drying, germinating energy and germination rate of pelleted seeds were improved. And emergence, establishment and early growth of pelleted were also improved in pasture under woodland. Based on this study, we could conclude that the seed pelleting is a useful technique for the establishment and early growth of grass under woodland.