• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.129-136
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• 2010

This study was initiated to investigate thatch accumulation in several turfgrasses grown under two soil systems. The 45 centimeter deep USGA system was constructed with rootzone, intermediate and drainage layers. The mono-layer system, however, was made with only a 30cm rootzone layer. Turfgrasses used in the study were comprised of 3 varieties from Korean lawngrass of Warm-Season Grass(WSG) and 3 blends and 3 mixtures from Cool-Season Grass(CSG). A total of 9 turfgrass treatments were replicated three times in RCBD in both systems. Cultural practices for the research plot followed a typical maintenance program for highly managed turf. Treatment differences for thatch accumulation were observed among the turfgrasses in both soil systems. Thatch under the USGA system was 9% greater than under the mono-layer system due to its more favorable conditions for turf growth. Higher thatch depth was found with Korean lawngrass, 34~87% in the USGA system and 16~75% in the mono-layer system when compared with CSG. Among WSG, the Joongji variety was the highest in thatch layer under both the USGA and mono-layer systems. Kentucky bluegrass(KB) was the greatest among CSG, since it is a rhizomatous-type in growth habit, resulting in faster production of organic matter over bunch-type of tall fescue and perennial ryegrass. Proper depth in the thatch layer was known to be beneficial by enhancing the resiliency and wear tolerance of the turf in athletic fields. Thus, KB was considered to be a very excellent turfgrass in terms of turf quality, environmental performance, physical properties and soccer player safety. However, disadvantages such as poor water-holding properties, more inclined to injury from environmental stresses and severe diseases and insect injury were also expected where thatch was excessively accumulated. Therefore, these results demonstrate that more frequent measures for controlling thatch such as vertical mowing, topdressing or coring should be employed for soccer fields with Korean lawngrass and KB over other turfgrasses.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.255-264
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• 2003

A study was conducted to determine the effects of pig slurry application on forage yield and growth of fazing Hanwoo heifer in a mixed pasture. To each of three treatments 1.4ha were alloted a control applied with only chemical fertilizer (N-P-K=150-150-120kg/ha), two pig slurry lots applied with the amount to allow 100% (150 kg/ha) or 150% (225 kg/ha) of N used in the control. A randomized block design was used without replication. Cattle were allowed to graze continuously during the experimental period. Results obtained were as follows: Total dry matter yield was 16,291, 15,632 and 16,320 kg/ha for chemical fertilizer. pig slurry 100% and 150％, respectively. The pasture was dominated by perenial ryegrass during the first gazing season, but by orchard grass and perenial ryegrass (60∼70%) and red clover (20∼30%) during the second grazing season. Average gazing rate per ha was 2.75∼2.76 animal units and daily weight gain of grazing cattle was not different among treatments ranging from 0.563 to 0.580 kg. Total weight gain of grazing cattle per ha during the grazing period was 541, 541 abd 555 kg for chemical fertilizer, pig -slurry 100 and 150%, respectively. RBC, WBC, total protein and albumin etc. concentrations in blood were normal in all treatments.

• Asian Journal of Turfgrass Science
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• v.17 no.1
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• pp.1-12
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• 2003

Research was Initiated to investigate germination characteristics of cool-season grasses (CSG). Several turfgrasses were tested in different experiments. Experiments I and III were conducted under a room temperature condition of 16$^{\circ}C$ to 23 $^{\circ}C$ and under a constant light condition at 25 $^{\circ}C$, respectively. An alternative environment condition that is a requirement for a CSG germination test by International Seed Testing Association (ISTA) was applied in the Experiment II, consisting of 8-hr light at 25 $^{\circ}C$ and 16-hr dark at 15 $^{\circ}C$. In each experiment, data such as early germinating vigor, germination speed and germination rate were evaluated. Six turfgrass entries were comprised of two varieties each from Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.), respectively. Significant differences were observed in early germinating vigor, germination speed and germination rate. Early germinating vigor as measured by days to 70% seed germination was variable according to environment conditions, turfgrasses and varieties. It was less than 6 days in PR and 6 to 9 days in TF. However, KB resulted in 11 to 13 days under an alternative condition and 11 to 28 days under a room temperature condition. The germination speed was fastest in PR of 7 to 10 days and slowest in KB of 14 to 21 days. However, intermediate speed of 10 to 14 days was associated with TF. There were considerable variations in germination rate among turfgrasses according to different conditions. Generally, PR and TF germinated well, regardless of environment conditions. However, a great difference was observed among KB varieties, when compared with others. Under a room temperature condition, total germination rate was 71.0% in Midnight and 77.7% in Award. And it increased under an alternative condition, which was 81.7% and 91.7% in Award and Midnight, respectively. However, the poorest rate was found under a constant temperature condition, resulting in 18.0% in Award and 15.3% in Midnight. These results suggest that an intensive germination test required by ISTA be needed prior to the decision of seeding rate, including early germinating vigor and germination speed as well as total germination rate. KB is very sensitive to environment conditions and thus its variety selection should be based on a careful expertise.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.62-69
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• 2013

The black cutworm, Agrotis ipsilon (Hufnagel), damages various cultivated crops and it can also be a serious pest of turfgrass, especially on golf courses. Essential oils have potential as alternative control agents for insect pests. Sixteen essential oils (anise, camphor, cinnamon, citronella, clove, fennel, geranium, lavender, lemongrass, linseed, neem, peppermint, pine, thyme, turpentine and tea saponin) and paraffin oil were assessed in the laboratory, the green house and field trials for their efficacy against black cutworms in turf. Treatment of potted cores of perennial ryegrass turf with anise, cinnamon, neem, paraffin or turpentine reduced black cutworm damage in a greenhouse trial, and in a similar trial, applying neem oil at 4000, 2000 and 1000 ppm resulted in 100, 100 and 64% mortality, respectively, of black cutworms. Weight of survivors at the 1000 ppm rate was 5- fold less than weight of comparably-aged controls. Neem oil (2000 ppm) reduced growth of black cutworms feeding on treated clippings. A high rate of neem oil followed by irrigation (0.1 L of 20000 ppm neem oil with 0.9 L watering/$m^2$) was more effective than a lower concentration (1 L of 2000 ppm neem oil/$m^2$) against $2^{nd}$ and $3^{rd}$ instars in potted turf cores and field plots, respectively. However, not even the aforementioned higher rate effectively controlled $4^{th}$ instars in the field.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.370-377
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• 2014

Research was initiated to evaluate cool-season grass (CSG) overseeding effects on coverage and species transition in Korean lawngrass (Zoysia japonica Steud.) and to determine CSGs and their seeding rate for a practical overseeding. Treatments were comprised of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), tall fescue (TF, Festuca arundinacea Schreb.) and their mixtures. Significant differences were observed in turfgrass coverage and species transition. Since overseeding, the coverage was highest in PR, followed by TF and lowest in KB. The highest coverage in polystand was associated with Mixture IV (TF 50 + PR 50) at a seeding rate of $150gm^{-2}$ which had highest PR and TF, but without KB. Regarding turfgrass transition, zoysiagrass recovery continued to come back up to 80% from late March. But it reduced after early October. Zoysiagrass in monostand was greatest in KB and lowest in TF, but variable in polystand. For the fast and great coverage in winter, it would be the best to apply with PR at $100gm^{-2}$ and equal combination of PR and TF by 1/2 in the mixture at $150gm^{-2}$. For the smooth spring transition to zoysiagrass, however, KB application at $50gm^{-2}$ is recommended.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.84-95
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• 2001

This study was conducted to suggest the ecological restoration methods for the decomposed granite roadside cutslopes by Natural Topsoil Restoration Methods(NTRM). Four woody species, 3 shrub species, 4 native grasses, 8 wild flowers and 2 cool-season grasses were used. The experiment was conducted with the purpose of developing ecological restoration techniques by achieving following objectives for restoration by using native woody plants, shrubs, native plants and wild flowers; (1) prevention or reduction of wind and water erosion, (2) provision of food and cover for variety of animal species, (3) improvement of the visual or aesthetic quality of disturbed sites. The main results were summarized as follows. 1. Restoring naturalness to human-altered landscapes are important to protecting the worlds biodiversity. In this study, to restore or create an ecological community use as full a complement of native species as possible. Ecological restoration means returning a specific sites to its predisturbance condition. 2. Some species which are introduced first may inhibit the germination and growth of slower-growing species, or they may prevent the growth of other species whose propagules arrive later. In this study, cool season grasses was used small amount than native plants and woody species, because and Indigofera pseudo-tintoria grows well. Tall fescue and perennial ryegrass shows quick germination, but they could not inhibit the other species growing relatively slow. Pinus thunbergii used at Gonam near the ocean was suppressed by the other plants, so it can be concluded that using container seedlings is effective than seeding. 4. Ailanthus altissima, Albizzia julibrissin, Rhus chinensis Lespedeza cyrtobotrya, and Indigofera pseudo-tinctoria were germinated. In wild flowers, Coreopsis lanceolata, Dianthus sinensis, Coreopsis tinctoria, and Lotus corniculatus var. japonicus grew well and show enough plant height which will not suppressed by shrub and woody plants. After one year, native grasses such as Arundinella hirta, Miscanthus sinensis var. purpurascens and Imperata cylindrica var. koenigii cover the slopes well. 5. 25 herbaceous plants such as Trifolium repens, Arthraxon hispidus, Barbarea orthocerae, Potentilla fragarioides, Lepidium apetalum, Chenopodium album var. centrorubrum, Glycine soja, Rubus crataegifolius and 4 woody species such as Lespedeza maximowiczii, Robinia pseudoacacia, Symplocos Chinensis, Quercus acutissma were invaded. 6. Ecological restoration works by Natural Topsoil Restoration Methods for revegetation of the decomposed granite roadside cutslopes were successfully accomplished. It prevents surface water erosion and shows diverse vegetation structure. It will be successful to restore decomposed granite cutslopes.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.514-522
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• 2017

Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1374-1388
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• 2007

Three experiments were conducted to investigate the hypothesis that cows grazing on pasture produce the highest proportion of c-9 t-11 CLA in milk fat and no further increase can be achieved through supplementation of diets rich in linoleic acid, such as full-fat extruded soybeans or soybean oil. In experiment 1, 18 lactating Holstein cows were used in a randomized complete block design with measurements made from wk 4 to 6 of the experiment. In experiment 2, three cannulated lactating Holstein cows were used in a $3{\times}3$ Latin square design. Each period was 4 wk with measurements made in the final wk of each period. Cows in both experiments were assigned at random to treatments: a, conventional total mixed ration (TMR); b, pasture (PS); or c, PS supplemented with 2.5 kg/cow per day of full-fat extruded soybeans (PES). In both experiments, feed intake, milk yield, milk composition, and fatty acid profile of milk and blood serum were measured, along with fatty acid composition of bacteria harvested from rumen digesta in experiment 2. In experiment 3, 10 cows which had continuously grazed a pasture for six weeks were assigned to two groups, with one group (n = 5) on pasture diet alone (PS) and the other group (n = 5) supplemented with 452 g of soy oil/cow per day for 7 d (OIL). In experiment 1, cows in PS treatment produced 350% more c-9, t-11 CLA compared with cows in TMR treatment (1.70 vs. 0.5% of fat), with no further increase for cows in PES treatment (1.50% of fat). Serum c-9, t-11 CLA increased by 233% in PS treatment compared with TMR treatment (0.21 vs. 0.09% of fat) with no further increase for cows in PES treatment (0.18% of fat). In experiment 2, cows in PS treatment produced 300% more c-9 t-11 CLA in their milk fat compared with cows in TMR treatment (1.77 vs. 0.59% of fat), but no further increase for cows in PES treatment (1.84% of fat) was observed. Serum c-9, t-11 CLA increased by 250% for cows in PS treatment compared with cows in TMR treatment (0.27 vs. 0.11% of fat), with no further increase for cows in PES treatment (0.31% of fat). The c-9, t-11 CLA content of ruminal bacteria for cows in PS treatment was 200% or more of TMR treatment, but no further increase in bacterial c-9, t-11 CLA for cows in PES treatment was observed. Supplementation of soy oil in experiment 3 also did not increase the c-9 t-11 CLA content of milk fat compared with cows fed a full pasture diet (1.60 vs. 1.54% of fat). Based on these findings, it was concluded that supplementing with feeds rich in linoleic acid, such as full-fat extruded soybeans or an equivalent amount of soy oil, to cows grazing perennial ryegrass pasture may not increase milk fat c-9 t-11 CLA contents.

• Annual Conference on Human and Language Technology
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• 1994.11a
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• pp.409-415
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• 1994

Hitel 과 같은 전자정보 시스템은 사용자가 원하는 정보를 체계적으로 얻을 수 있도록 하기 위하여 메뉴들을 적당히 계층적으로 구성하여 제공하고 있다. 그러나, 보통 이 메뉴들의 계층이 정확한 분류법에 기초하여 만들어지지 않았을 뿐 아니라 그 양도 엄청나게 방대하여, 이 메뉴 계층을 이용하여 사용자가 원하는 정보를 얻기가 쉽지 않다. 실험적으로 보통 Hitel을 자주 이용하는 사람들도 자신이 주로 이용하는 메뉴들의 구성만 이해하고 있을뿐, 사용하지 않는 부분의 메뉴들의 구성은 잘 알지 못하는 것이 일반적이었다. 따라서 Hitel을 자주 이용하는 사용자도 자신이 이용해 보지 않은 정보를 얻기 쉽지 않으며, 더더욱 초보자에게는 이 메뉴계층을 이용하여 원하는 정보를 얻기가 쉽지 않은 실정이다. 본 연구에서는 정보검색 기술을 이용하여 Hitel과 같은 전자정보 시스템에서 사용자가 쉽게 자신이 원하는 정보를 얻을 수 있는 보조 시스템을 개발하고자 한다. 본 시스템은 사용자가 메뉴계층을 이용하기 전에 간략한 자연어로 입력을 주면, 여기에 적합한 메뉴나 실제 정보를 검색해 낸다. 따라서 사용자는 이 메뉴정보를 이용하여 메뉴계층을 쉽게 따라갈 수 있을 뿐 아니라, 경우에 따라서는 원하는 실제 정보를 검색하기 때문에 메뉴계층을 탐색할 필요가 없다. 본 연구에서는 자연어 입력을 최장 일치 방법으로 의미있는 명사들을 추출하여 불리한 질의어로 만든 후, 명사들 사이의 관계가 표현된 시소러스를 이용하여 이 질의어를 확장시킨다. 다음에 이 질의어들을 메뉴들과 부분/정확부합을 통하여 관련된 메뉴들을 찾아낸 후, 이들의 계층과제를 고려하여 최종 메뉴들을 검색한다. 본 시스템은 현재 C언어로 만들어져 구동중이며, 정확한 실험은 아직 하지 않았지만 높은 검색율을 보이고 있다. industrialized, was improved by introducing pressure in cooling procedure for both carbon and iron thermistors.er>$CHCl_3$>Hexane층 순으로 높은 활성을 나타냈다. 5. 아질산염소거능은 끝순, 들깨잎, 콩나물이 우수하였고 그중 들깨잎이 저해율 72%로 가장 높았으며, 용매분획 중에는 BuOH과 water추출물의 활성이 가장 높았다. 6. ACE 저해 효과는 고구마 부위별로는 끝순이 괴근에 비하여 1.5배 높았고, 들깨잎, 콩나물, 시금치보다 $1.9{\sim}3.7$배 높았다. 용매분획별로는 EtOAc, BuOH, water 추출물이 높은 활성을 보였다. 7. 이상을 종합하여 볼 때 고구마 끝순에는 페놀화합물이 다량 함유되어 있어 높은 항산화 활성을 가지며, 아질산염소거능 및 ACE저해활성과 같은 생리적 효과도 높아 기능성 채소로 이용하기에 충분한 가치가 있다고 판단된다.등의 관련 질환의 예방, 치료용 의약품 개발과 기능성 식품에 효과적으로 이용될 수 있음을 시사한다.tall fescue 23%, Kentucky bluegrass 6%, perennial ryegrass 8%) 및 white clover 23%를 유지하였다. 이상의 결과를 종합할 때, 초종과 파종비율에 따른 혼파초지의 건물수량과 사료가치의 차이를 확인할 수 있었으며, 레드 클로버 + 혼파 초지가 건물수량과 사료가치를 높이는데 효과적이었다.\ell}$ 이었으며 , yeast extract 첨가(添加)하여 배양시(培養時)는 yeast extract 농도(濃度)가 증가(增加)함에 따라 단백질(蛋白質) 함량(含量)도 증가(增加)하였다. 7. CHS-

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.325-325
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• 2017

In the 20th century, the average temperature of Korea has risen by $1.5^{\circ}C$, whereas it has risen by $0.6^{\circ}C$ globally. Few studies have investigated the effect of seeding date in hilly pastures on their growth characteristics and productivity. The purpose of this study was to elucidate the effect of seeding dates at a hilly pasture establishment on its growth characteristics and productivity caused by increasing temperatures in Korea. The experiments were conducted from 2014 to 2016 at Pyeongchang, South Korea, at an altitude 600-700 m above sea level. The composition of grass mixture was tall fescue, orchard grass, perennial ryegrass, Kentucky bluegrass, timothy, and white clover. Treatments comprised four seeding dates (August 13 and 27, and September 10 and 24). The establishment rate was lowest on September 24, resulting in only 20% establishment over the winter, and the proportion of weeds was highest on September 24 (58%). Early seedling growth before overwintering is a critical approach to ensure successful establishment of grassland. The main components were orchard grass and tall fescue on the early seeding date (August 13), and Kentucky bluegrass on the late seeding date (September 24). Late seeding increased the proportion of bare lands invaded by weed species, especially during second and third cutting periods. Early seeding date resulted in a progressive increase in biomass. Total annual production was significantly affected by the seeding date; lowest dry matter production was on September 24 ($2,441kg\;ha^{-1}$), whereas maximum dry matter yield was on August 27 ($6,608kg\;ha^{-1}$). The results of the study indicate that growth condition and productivity could be increased by early seeding, and seeding of grass in the Pyeongchang area should be completed before August 27. However, further studies are needed to determine the ideal seeding date at the hilly pasture establishment in Pyeongchang.