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Comparative study of Seed Productivity of Spring Sown Italian Ryegrass(Lolium multiflorum Lam.) Depending on Seeding Distance in Gangwon Highland (강원 고지대에서 봄 파종 이탈리안 라이그라스(Lolium multiflorum Lam.)의 파종 간격에 따른 종자 생산성 비교 연구)

  • Jeong, Eun Chan;Li, Yan Fen;Kim, Hak Jin;Kim, Meing Joong;Ji, Hee Chung;Kim, Jong Geun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.41 no.1
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    • pp.16-22
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    • 2021
  • This experiment was conducted to study on the growth characteristics and seed productivity of Italian ryegrass (Lolium multiflorum Lam., IRG) planted in the Spring in Gangwon Highland according to the seeding distance (20, 30 and 40 cm). The field was located in highland around 600 m above sea level. The experimental design was randomized block design with three replication and the tested IRG variety was 'Greencall' developed by National Institute of Animal Science (NIAS). IRG was sown on March 26, 2020, and harvested on July 2. The plant height was the shortest at 80.5 cm in the 40 cm seeding distance plot (P<0.05), and there was no significant difference between the 20 and 30 cm seeding distance. The number of spike per square meter (㎡) was significantly higher in the 20 cm seeding distance plot than that of 40 cm (937 vs. 571). The dry matter (DM) content of seed and straw after harvesting was 49.70 and 33.36 % on average, and there was no significant difference between treatments (P>005). However, there was a significant difference in the fresh and DM yield of seeds and straw (P<0.05). DM yield of seeds was significantly higher in 20 cm distance than that of 40 cm, and the yield of straw was the same trend. On the other hand, there was no significant difference in DM yield between 20 cm and 30 cm and also in the feed value of straw after seed harvesting among seeding distance. The average CP, ADF, NDF, and TDN contents were 6.91, 36.76, 61.75 and 59.86%, respectively, and the RFV value was 91. Considering the above results, the production of Italian ryegrass seeds sown in the spring in the highlands of the Gangwon is lower than that of autumn sowing, but it is judged that it needs to be reviewed in case it is unavoidable. In the future, there should be an economic analysis and the development of technology that can increase production.

Seed Productivity by Varieties of Italian Ryegrass(Lolium multiflorum Lam.) Sown in Spring in Gangwon Highlands (강원 고지대에서 봄 파종한 이탈리안 라이그라스(Lolium multiflorum Lam.)의 품종에 따른 종자 생산성)

  • Jeong, Eun Chan;Kim, Hak Jin;Li, Yan Fen;Kim, Meing Joong;Ji, Hee Chung;Kim, Jong Geun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.40 no.4
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    • pp.221-226
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    • 2020
  • This experiment was conducted to compare the seed productivity of the Italian ryegrass(Lolium multiflorum Lam.) varieties sown in the spring in Gangwon region. The experiment was randomized block design with three replications. The Experimental field was located in alpine areas of about 600 m above sea level in Gangwon province. The tested Italian Ryegrass varieties were 'Greenfarm', 'Greencall' and 'Kowinearly' developed by National Institute of Animal Science, RDA. Italian Ryegrass varieties were sown on March 26, 2020, and the harvest was on the 60th day of mean heading date, July 2. The heading date of Kowinearly was May 8, but Greenfarm and Greencall was May 4. The plant length was the largest in the Kowinearly variety. However, the Kowinearly suffered severe lodging. There was no significant difference in the length of spike among varieties, and the number of seeds per spike was the lowest in Greenfarm at 118.5 seed/spike. As for the seed weight per spike, the Greenfarm variety was significantly lower at 0.56 g/spike, but the 1,000 seed weight was the heaviest in the Greenfarm at 2.5g.. The number of spike per unit area was the highest in Greenfarm at 906/㎡. The dry matter content of seeds was the highest in Greenfarm at 54.3%, and for straw, Kowinearly was the highest at 35.3%. Seed productivity was not significant among varieties, and the average was 1,493 kg/ha. The yield of straw after seed production was also not significant among varieties (P>0.05), and the average was 3,172 kg/ha. From the above results, the production of Italian ryegrass seeds through spring sowing in the Gangwon region is not much than autumn seeding, requiring the input of various technologies to increase productivity in the future, and it is desirable to determine the production cost through economic analysis was judged.

The Interrelationship between Riparian Vegetation and Hydraulic Characteristics during the 2020 Summer Extreme Flood in the Seomjin-gang River, South Korea (2020 여름 섬진강 대홍수시 하안식생과 수리 특성의 상호관계)

  • Lee, Cheolho;Lee, Keonhak;Kim, Hwirae;Baek, Donghae;Kim, Won;Kim, Daehyun;Lee, Hyunjae;Woo, Hyoseop;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
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    • v.8 no.2
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    • pp.79-87
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    • 2021
  • Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.

Investigation and Processing of Seismic Reflection Data Collected from a Water-Land Area Using a Land Nodal Airgun System (수륙 경계지역에서 얻어진 육상 노달 에어건 탄성파탐사 자료의 고찰 및 자료처리)

  • Lee, Donghoon;Jang, Seonghyung;Kang, Nyeonkeon;Kim, Hyun-do;Kim, Kwansoo;Kim, Ji-Soo
    • The Journal of Engineering Geology
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    • v.31 no.4
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    • pp.603-620
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    • 2021
  • A land nodal seismic system was employed to acquire seismic reflection data using stand-alone cable-free receivers in a land-river area. Acquiring reliable data using this technology is very cost effective, as it avoids topographic problems in the deployment and collection of receivers. The land nodal airgun system deployed on the mouth of the Hyungsan River (in Pohang, Gyeongsangbuk Province) used airgun sources in the river and receivers on the riverbank, with subparallel source and receiver lines, approximately 120 m-spaced. Seismic data collected on the riverbank are characterized by a low signal-to-noise (S/N) and inconsistent reflection events. Most of the events are represented by hyperbola in the field records, including direct waves, guided waves, air waves, and Scholte surface waves, in contrast to the straight lines in the data collected conventionally where source and receiver lines are coincident. The processing strategy included enhancing the signal behind the low-frequency large-amplitude noise with a cascaded application of bandpass and f-k filters for the attenuation of air waves. Static time delays caused by the cross-offset distance between sources and receivers are corrected, with a focus on mapping the shallow reflections obscured by guided wave and air wave noise. A new time-distance equation and curve for direct and air waves are suggested for the correction of the static time delay caused by the cross-offset between source and receiver. Investigation of the minimum cross-offset gathers shows well-aligned shallow reflections around 200 ms after time-shift correction. This time-delay static correction based on the direct wave is found essential to improving the data from parallel source and receiver lines. Data acquisition and processing strategies developed in this study for land nodal airgun seismic systems will be readily applicable to seismic data from land-sea areas when high-resolution signal data becomes available in the future for investigation of shallow gas reservoirs, faults, and engineering designs for the development of coastal areas.

A Research of Cultural Heritage and Business Value of the Juk-Bang-Ryeum(Fishing Instrument made-by Bamboo Weir) (죽방렴의 문화유산적 가치와 비즈니스적 가치 탐색 연구)

  • Kang, Myeong Hwa;Lee, Kyung-Joo;Kwon, Hojong;Jeong, Dae-Yul
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.8 no.12
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    • pp.425-435
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    • 2018
  • The purpose of this study is to investigate the cultural value as well as business value of Juk-Bang-Ryeum(fishing instrument made by bamboo weir) by the investigation of remains in Gyeongnam Sacheon area and reviewing various historical literatures. The research will contribute to make back data necessary for the registration of World Heritage(UNESCO) and Globally Important Agricultural Heritage Systems(FAO). Fisheries, along with agriculture, have been great significance in human history. In particular, the Fisheries has been considered very important industry due to the geopolitical characteristics of our country surrounded by the sea. We can imagine may types of fishing practices and instruments at the agricultural age. Nonetheless, there are a few fishery heritages such as collecting and hunting tools that remains today. Fortunately, there are many Juk-Bang-Ryeum which is actually operate now from the past 500 years ago at the The Sacheon and Namhae areas. We could found some literature records about it in the historical ancient literatures. We could also infer that Juk-Bang-Ryeum was an important fishery resource of the country for a long time. It was built on the basis of scientific principles to capture fishes using the rapid tide of the natural geological straits, and it prove the wisdom of our ancestors. We also could found some unique cultural heritages that was important to the local community. Naturally, it has been managed as an important asset for the residents. In addition to such historical and humanistic values, it also has business and educational value. It can be useful to understand scientific fishery principles as well as fishery experience field. It has business value as an important tourism resource in the region in connection with historical relics and geological environment resources. In conclusion, it is a valuable asset to be handed down as a valuable cultural heritage.

Comparison of Dissolved Ammonium Analytical Method in Seawater: Spetrophotometry and Fluorometry (해수 중 용존 암모늄 분석방법 비교: 분광광도법과 형광법)

  • SON, PURENA;PARK, JOONSEONG;RHO, TAEKEUN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.25 no.4
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    • pp.81-96
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    • 2020
  • Berthlot's reaction spectrophotometric method is generally used for the analysis of dissolved ammonium in seawater, but in recent years, a fluorescence method using an orthophthaldialdehyde-sulfite (OPA) fluorescent reagent is actively used internationally. In this study, we investigated the effects of the detection limit between the analysis methods, the reagent refractive index inherent in the spectrophotometric method, and the use of different calibration curves to understand the cause of the difference in dissolved ammonium concentration (about 0.31 𝜇M) observed in the seawater samples and a nutrient reference material between two institutions (KIOST (spectrophotometric method, one-order linear regression gradient only), Australia CSIRO (fluorescence method, quadratic formula)) conducted onboard the Australian R/V Investigator in 2017. The method detection limit (0.063 𝜇M) and the reagent refractive index background value (0.054 𝜇M) of the spectrophotometric method measured in this study could explain the difference in dissolved ammonium concentration values of the two institutes about 20% and 17%, respectively. However, when the concentration of the calibration curve of the spectrophotometric method was calculated using the same quadratic as the fluorescence method or the slope and intercept of linear regression, the difference in the dissolved ammonium concentration between the two institutions was reduced to less than the detection limit of the spectrophotometric method. Therefore, the difference in the concentration of dissolved ammonium between the two institutions, found in the nutrient reference materials and the seawater field sample during the international onboard nutrient inter-comparison experiment, may be attributed to be the effect of the different calibration curves used in the two methods rather than the effect of the difference in two analytical methods. When comparing the dissolved ammonium data from seawater samples in the future, it is recommended to pay attention to the information on the baseline, number of standard solutions, and calibration curve used in the analysis.

An Introduction to the Study of the Outlook on the Highest Ruling Entity in Daesoonjinrihoe (II) - Focusing on 15 Godship and Yang-wui Sangje (Sangje in two Godship) - (대순진리회 상제관 연구 서설 (II) - 15신위와 양위상제를 중심으로 -)

  • Cha, Seon-keun
    • Journal of the Daesoon Academy of Sciences
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    • v.23
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    • pp.241-292
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    • 2014
  • This article as an attempt to analyze Jin-beop-joo(眞法呪, incantation of true law) and the view of Yang-wui Sangje(兩位上帝, Sangje in two Godship) corresponds to the second preliminary work prior to the research on the view of Sangje in Daesoonjinrihoe. The points of this article are as follows: First, Jin-beop-joo and 15 Godship(神位) based hereupon are one of the most essential elements comprising the view of Sangje in Daesoonjinrihoe. Since the other Jeungsan line religious orders except Daesoonjinrihoe does not use 15 Godship in explaining and understanding Jeungsan, this fact should be regarded as an important characteristic of Daesoonjinrihoe. Second, 15 Godship is the important installation to assemble Sangje and the other gods in the same place. In Buddhism temples and China-Taoism temples, the gods each are placed in a separate palace. Whereas Sangje and the gods are concentrated in the same place, Yound-Dae(靈臺) which is the shrine of Daesoonjinrihoe. This fact shows Sangje takes the reins to the gods visually. 15 Godship facilitates that system. Third, the number 15 of 15 Godship symbolizes the natural laws of the cosmos. Thus the shrine of Daesoonjinrihoe implies the law of universe emblematically. Forth, 15 Godship shows that the Highest God in Daesoonjinrihoe are located in the middle of the functional gods ruling over nature like mountain, sea, season, the Great Dipper, and Taoistic or Buddhistic gods like Ok-hwang Sangje(玉皇上帝, The Great Jade Emperor), Seoga-Yeorae(釋迦如來, Tathāgata Buddha), Kwan-seong-Jegoon(關聖帝君, Holy god Guan Yu), along with various envoys and ancestral gods. Besides, considering the fact that the majority of 15 Godship consists of the Eastern deities, it verifies the view of Sangje in Daesoonjinrihoe is built in the Eastern religions. Fifth, whereas the other Jeungsan line religious orders have a tendency of understanding Jeungsan as Ok-hwang Sangje, Daesoonjinrihoe worships Jeungsan as Gu-cheon Sangje(九天上帝), not as Ok-hwang Sangje. This accords with the following fact; Jeungsan is the highest ruling entity in Gu-cheon, whereas in Jinbeonju, which was handed down from Jeungsan, the highest ruling entitiy in Gu-cheon is expressed as a different being from Ok-hwang Sangje. Sixth, Daesoonjinrihoe understands Sangje as the form of two Godship, Yang-wui Sangje, which are Gu-cheon Sangje and Ok-hwang Sangje. Judging from the form of salutation, the status of these two Sangjes are the same. Yet, the object of belief is Gu-cheon Sangje as the highest God, while Ok-hwang Sangje is stipulated as the one who has wielded a true law succeeding to the Gu-cheon Sangje's will. The religious term of Yang-wui Sangje don't imply meaning Gu-cheon Sangje and Ok-hwang Sangje are the same rank. Yang-wui Sangje is the term expresses Sangje in two Godship and involves the orthodox heritage of Daesoonjinrihoe. Along with An Introduction to the Study of the Outlook on the Highest Ruling Entity in Daesoonjinrihoe (I), this article is written, while giving a thought to construct the religiography on the highest God in Daesoonjinrihoe. I hope this article accompanied with the previous one, can be contributed to the fertilization of the soil in the field of Daesoon religious studies.

Introduction to the Benthic Health Index Used in Fisheries Environment Assessment (어장환경평가에 사용하는 저서생태계 건강도지수(Benthic Health Index)에 대한 소개)

  • Rae Hong Jung;Sang-Pil Yoon;Sohyun Park;Sok-Jin Hong;Youn Jung Kim;Sunyoung Kim
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.779-793
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    • 2023
  • Intensive and long-term aquaculture activities in Korea have generated considerable amounts of organic matter, deteriorating the sedimentary environment and ecosystem. The Korean government enacted the Fishery Management Act to preserve and manage the environment of fish farms. Based on this, a fisheries environment assessment has been conducted on fish cage farms since 2014, necessitating the development of a scientific and objective evaluation method suitable for the domestic environment. Therefore, a benthic health index (BHI) was developed using the relationship between benthic polychaete communities and organic matter, a major source of pollution in fish farms. In this study, the development process and calculation method of the BHI have been introduced. The BHI was calculated by classifying 225 species of polychaetes appearing in domestic coastal and aquaculture areas into four groups by linking the concentration gradient of the total organic carbon in the sediment and the distributional characteristics of each species and assigning differential weights to each group. Using BHI, the benthic fauna communities were assigned to one of the four ecological classes (Grade 1: Normal, Grade 2: Slightly polluted, Grade 3: Moderately polluted, and Grade 4: Heavily polluted). The application of the developed index in the field enabled effective evaluation of the Korean environment, being relatively more accurate and less affected by the season compared with the existing evaluation methods like the diversity index or AZTI's Marine Biotic Index developed overseas. In addition, using BHI will be useful in the environmental management of fish farms, as the environment can be graded in quantified figures.

Macrobenthic Community Structure Along the Environmental Gradients of Ulsan Bay, Korea (울산만의 저서환경 구배에 따른 저서동물군집 구조)

  • Yoon, Sang-Pil;Jung, Rae-Hong;Kim, Youn-Jung;Kim, Seong-Gil;Choi, Min-Kyu;Lee, Won-Chan;Oh, Hyun-Taik;Hong, Sok-Jin
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.2
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    • pp.102-117
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    • 2009
  • This study was carried out to investigate the extent to which benthic environment of Ulsan Bay was disturbed by organic materials and trace metals from the megacity and industrial complex. Field survey for benthic environment and macroinvertebrate community was seasonally conducted from February to November 2006 at nine stations covering the inside and outside of the bay. TOC was on average 1.7% while four (As, Cu, Pb, Zn) out of seven trace metals measured exceeded the Effects Range Low (ERL) in most of the stations. Total number of species sampled was 199 and mean density was 4,578 ind./$m^2$, both of which were greatly dominated by the polychaetes. Dominant species were Aphelochaeta monilaris (22.6%), Ruditapes philippinarum (17.1%), Magelona japonica (12.2%), Lumbrineris longifolia (9.9%) and their distribution was ruled by the difference in the benthic environmental condition of each station. From the multivariate analyses, four stational groups were identified: northern part of the bay, middle and lower part of the bay, the intersection of Taewha River and Gosa stream and outside of the bay. As a result, the community heterogeneity of inner bay was much more greater than that of outer bay. SIMPER analysis showed that four groups were represented by R. philippinarum-Capitella capitata, A. monilaris-Balanoglossus carnosus, Sinocorophium sinensis-Cyathura higoensis and M. japonica-Ampharete arctica, respectively. Spatio-temporal changes of macroinvertebrate communities in Ulsan Bay were closely related to those of depth, mean grain size and organic content, and Zn was also a meaningful factor in that context.

Spatio-temporal Changes in Macrobenthic Community Structure and Benthic Environment at an Intensive Oyster Culturing Ground in Geoje-Hansan Bay, Korea (굴 양식장 밀집해역인 거제한산만의 저서동물군집 구조와 저서환경의 시.공간적 변동)

  • Yoon, Sang-Pil;Jung, Rae-Hong;Kim, Youn-Jung;Hong, Sok-Jin;Oh, Hyun-Taik;Lee, Won-Chan
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.4
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    • pp.213-228
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    • 2009
  • This study was conducted to investigate spatio-temporal changes in macrobenthic community structure and benthic environmental conditions in Geoje-Hansa Bay, which is the greatest oyster producing site in Korea. Field survey for benthic environment and macrobenthos was seasonally carried out at 15 stations covering oyster farming sites and non-farming sites from February to November, 2008. The grain size of surface sediments was dominated by very fine silt with the mean phi of about $9\;{\Phi}$ and TOC was 1.9% on average. Mean dissolved oxygen content was 8.1 mg/L and lowest in August corresponding to the 2nd degree in seawater quality criteria. Total species number was 351 and mean density was $3,675\;ind./m^2$, both of which were dominated by polychaete worms. Spatio-temporal variation in above two biological variables was great with higher values seasonally in spring and spatially in channels rather than inner bay. Dominant species were Lumbrineris longifolia (21.3%), Aphelochaeta monilaris (17.8%) and Ericthonius pugnax(6.1%), all of which are typical species of organically enriched area. From the multivariate analyses, the whole macrobenthic community was distinguished into two groups of channel and inner bay group. Spatio-temporal changes of macrobenthic community in Geoje-Hansan Bay were related to those of TOC and acid volatile sulfide (AVS). Our results showed that Geoje-Hansan Bay should be intermediately affected by organic pollution, and that such organic enrichment was more remarkable at farming stations in the inner bay.