• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.42-49
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• 1983

In order to find out the possibility of predicting fertilizer K requirement from the K supplying capacity of soil, the relative K activity ratio, Kas/kai, the potential buffering capacity of $K^+$ ($PBC^k$ ; the liner regression coefficient) and its activity ratio ($AR^k_o$ ; $^{k+}$/${\sqrt{Ca^{+2}+Mg^{+2}}}$ in mol/l) at ${\delta}K$ = O, in the Q/I relationships of Beckett(1964), were determined for the soils before flooding and the samples taken at heading stage of transplanted rice in pot experiment. These parameters assumed as the K supplying capacity of soils were subjected for the investigation through correlation stady between themselves and other factors such as grain yield or the amounts of $K_2O$ uptake by rice plant at harvest. The results may be summarized as follows; 1. The potassium supplying power of the flooded soil was considered to be ruled by the amounts of exchangeable K before flooding, since there was little change in exchangeable K concentration from no-exchangeable K during the incubation periods of 67 days. 2. The $PBC^k$ values, in soils before flooding were 0.027, 0.014 and 0.009, where as the $AR^k_o{\times}10^{-3}$ values were 9.1, 7.6, and 15.4, respectively, in clay, loamy and sandy loam soils. 3. The $PBC^k$ values, determined in the soil samples taken at heading stage, varied little compared with the values of orignal soil, regardless of those different fertilizer treatments and textures, showing the possibility of using them as a factor for the improvement of soil to increase the efficiency of fertilizer K. 4. The significant yield responses to potassium fertilizer application were observed wherever the $AR^k_o$ values in soil at heading stage drop down to the original $AR^k_o$ values, regardless of any levels of fertilizer application. 5. The higher correlations between the gain yield or the amounts of $K_2O$ uptake and by the use of both soil factors of $PBC^k$ and $AR^k_o$ at heading stage were observed compared with the use of any single factor. 6. The Kas/Kai value in the soil, estimated prior to the experiment, had high possitive correlation with the $AR^k_o$ determined in the soil at heading stage and could be used as a soil factor for predicting potassium fertilizer requirement.

• Korean Journal of Heritage: History & Science
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• v.39
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• pp.95-130
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• 2006

Japanese government college researchers, including Sekino Tadashi(關野貞), have conducted research studies and collected data, on overall Korean cultural relics as well as Silla tumuli(新羅古墳) in the early modern times under the Japanese imperialistic rule. They were supported by the Meichi government in the early stage of research, by the Chosun government-general, and by their related organizations after Korea was coIonialized to carry out investigations on Korean antiquities, fine arts, architecture, anthropology, folklore, and so on. The objective for which they prosecuted inquiries into Korean cultural relics, including Silla tumuli, may be attributed to the purport to find out such data as needed for the theoretical foundation to justify their colonialization of Korea. Such a reason often showed locally biased or distorted views. Investigations and surveys had been incessantly carried out by those Japanese scholars who took a keen interest in Korean tumuli and excavated relics since 1886. 'Korea Architecture Survey Reports' conducted in 1904 by Sekino in Korea gives a brief introduction of the contents of Korean tumuli, including the Five Royal Mausoleums(五陵). And in 1906 Imanishi Ryu(今西龍) launched for the first time an excavation survey on Buksan Tumulus(北山古墳) in Sogeumgangsan(小金剛山) and on 'Namchong(南塚)' in Hwangnam-dong, which greatly contributed to the foundation of a basic understanding of Wooden chamber tombs with stone mound(積石木槨墳) and stone chambers with tunnel entrance(橫穴式石室墳). The ground plan and cross section of stone chambers made in 1909 at his excavation survey of seokchimchong(石枕塚) by Yazui Seiyichi(谷井第一) who majored in architecture made a drawing in excavation surveys for the first time in Korea, in which numerical expressions are sharply distinguished from the previous sketched ones. And even in the following excavation surveys this kind of drawing continued. Imanishi and Yazui elucidated that wooden chambers with stone mound chronologically differs from the stone chambers with tunnel entrance on the basis of the results of surveys of the locational characteristics of Silla tumuli, the forms and size of tomb entrance, excavated relics, and so forth. The government-general put in force 'the Historic Spots and Relics Preservation Rules' and 'the Historic Spots Survey Council Regulations' in 1916, establishing 'Historic Spots Survey Council and Museum Conference. When museums initiated their activities, they exhibited those relics excavated from tumuli and conducted surveys of relics with the permission of the Chosun government-general. A gold crown tomb(金冠塚) was excavated and surveyed in 1921 and a seobong tomb(瑞鳳塚) in 1927. Concomitantly with this large size wooden chamber tombs with stone mound attracted strong public attention. Furthermore, a variety of surveys of spots throughout the country were carried out but publication of tumuli had not yet been realized. Recently some researchers's endeavors led to publish unpublished reports. However, the reason why reports of such significant tumuli as seobong tomb had not yet been published may be ascribed to the critical point in those days. The Gyeongju Tumuli Distribution Chart made by Nomori Ken(野守健) on the basis of the land register in the late 1920s seems of much significance in that it specifies the size and locations of 155 tumuli and shows the overall shape of tumuli groups within the city, as used in today's distribution chart. In the 1930s Arimitsu Kyoichi(有光敎一) and Saito Tadashi(齋藤忠) identified through excavation surveys of many wooden chamber tombs with stone mound and stone chambers with tunnel entrance, that there were several forms of tombs in a tomb system. In particular, his excavation survey experience of those wooden chamber tombs with stone mound which were exposed in complicated and overlapped forms show features more developed than that of preceding excavation surveys and reports publication, and so on. The result of having reviewed the contents of many historic spots surveyed at that time. Therefore this reexamination is considered to be a significant project in arranging the history of archaeology in Korea.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.7-31
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• 2000

Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.339-348
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• 2006

Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted on masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased.4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

• Economic and Environmental Geology
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• v.30 no.4
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• pp.289-301
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• 1997

The Boguk cobalt mine is located within the Cretaceous Gyeongsang Sedimentary Basin. Major ore minerals including cobalt-bearing minerals (loellingite, cobaltite, and glaucodot) and Co-bearing arsenopyrite occur together with base-metal sulfides (pyrrhotite, chalcopyrite, pyrite, sphalerite, etc.) and minor amounts of oxides (magnetite and hematite) within fracture-filling $quartz{\pm}actinolite{\pm}carbonate$ veins. These veins are developed within an epicrustal micrographic granite stock which intrudes the Konchonri Formation (mainly of shale). Radiometric date of the granite (85.98 Ma) indicates a Late Cretaceous age for granite emplacement and associated cobalt mineralization. The vein mineralogy is relatively complex and changes with time: cobalt-bearing minerals with actinolite, carbonates, and quartz gangues (stages I and II) ${\rightarrow}$ base-metal sulfides, gold, and Fe oxides with quartz gangues (stage III) ${\rightarrow}$ barren carbonates (stages IV and V). The common occurrence of high-temperature minerals (cobalt-bearing minerals, molybdenite and actinolite) with low-temperature minerals (base-metal sulfides, gold and carbonates) in veins indicates a xenothermal condition of the hydrothermal mineralization. High enrichment of Co in the granite (avg. 50.90 ppm) indicates the magmatic hydrothermal derivation of cobalt from this cooling granite stock, whereas higher amounts of Cu and Zn in the Konchonri Formation shale suggest their derivations largely from shale. The decrease in temperature of hydrothermal fluids with a concomitant increase in fugacity of oxygen with time (for cobalt deposition in stages I and II, $T=560^{\circ}C-390^{\circ}C$ and log $fO_2=$ >-32.7 to -30.7 atm at $350^{\circ}C$; for base-metal sulfide deposition in stage III, $T=380^{\circ}-345^{\circ}C$ and log $fO_2={\geq}-30.7$ atm at $350^{\circ}C$) indicates a transition of the hydrothermal system from a magmatic-water domination toward a less-evolved meteoric-water domination. Sulfur isotope data of stage II sulfide minerals evidence that early, Co-bearing hydrothermal fluids derived originally from an igneous source with a ${\delta}^{34}S_{{\Sigma}S}$ value near 3 to 5‰. The remarkable increase in ${\delta}^{34}S_{H2S}$ values of hydrothermal fluids with time from cobalt deposition in stage II (3-5‰) to base-metal sulfide deposition in stage III (up to about 20‰) also indicates the change of the hydrothermal system toward the meteoric water domination, which resulted in the leaching-out and concentration of isotopically heavier sulfur (sedimentary sulfates), base metals (Cu, Zn, etc.) and gold from surrounding sedimentary rocks during the huge, meteoric water circulation. We suggest that without the formation of the later, meteoric water circulation extensively through surrounding sedimentary rocks the Boguk cobalt deposits would be simple veins only with actinolite + quartz + cobalt-bearing minerals. Furthermore, the formation of the meteoric water circulation after the culmination of a magmatic hydrothermal system resulted in the common occurrence of high-temperature minerals with later, lower-temperature minerals, resulting in a xenothermal feature of the mineralization.

• Journal of Korean Society of Forest Science
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• v.33 no.1
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• pp.1-32
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• 1977

This study has been made to find out more effective way of vegetation establishment on severely denuded forest land from the viewpoint of soil moisture regimes. Various environmental factors were measured to estimate soil moisture conditions of different sites. Soil moisture influence on growth of over vegetations, water requirement and drought resistance were analyzed. The efficiency of water use was also reckoned at different fertility levels and different soil moisture conditions. This research is composed of field experiment and green house experiment. Field experiment includes height growth, survival and coverage analysis of cover vegetations (Robinia pseudoacacia L., Lespedeza bicolor Turcz, Arundinella hirta Tanaka var. ciliare Koidzumi.) with 4 fertility level treatments on 3 slopes (Steep: $37^{\circ}$, Moderate: $25^{\circ}$, Gentle; $17^{\circ}$) during dry season (1 April-30 June) and wet season (1 July-10 September). At the same time temperature, relative humidity and precipitation were measured to understand the environmental changes. Soil moisture conditions were measured with soil moisture meter with 24 soil cells. Green house experiment comprised height, fresh weight and dry weight measurements of cover vegetations with 4 fertility levels and 3 moisture conditions for 70 days. The results extracted from experiments are as follews. 1. Cover vegtations have 3 patterns of water requirement at the early stage of growth. a) Robinia type has high water requirement and weaker drought resistance. b) Lespedeza type has low water requirement and stronger drought resistance. c) Arundinella type has moderate water requirement and weaker drought resistance. 2. The vegetations have different optimum fertility levels in different soil moisture supply condition. a) Robinia needs a low fertility level in dry condition and a high level in wet condition. b) Lespedeza needs only low fertility level in all conditions. c) Arundinella needs a low fertility level in dry condition and a high level in wet condition. 3. The efficiency of water use (Water/1g dry weight) by fertility levels is different from one another. Robinia and Arundinella have a good efficiency at low fertility level in dry condition and at high fertility level in wet condition. Lespedeza has a good efficiency at low fertility level in all conditions. 4. $P_2O_5$ requirement of Robinia and Lespedeza is high, but that of Arundinella is low. Soil moisture condition has a great influence on $P_2O_5$ absorption in dendued forest land. Once Vegetations are established on suitable sites with optimum fertitity level according to different moisture condition, even the small amount of soil water in denuded land can he used with high efficiency and the effect of fertility treatment can be maximized.

• Journal of Arbitration Studies
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• v.16 no.1
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• pp.343-373
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• 2006

지적재산권의 속지주의 원칙에 따라 전통적으로 지적재산권의 침해에 있어서 결과의 발생이 없는 행위지를 침해지로 인정하지 않았다. 어문과 예술작품을 보호하기 위해 1886년 체결된 베른협약(Berne Convention for the Protection of Literary and Artistic Works) 제5조 제1항은 저작자가 베른협약에 따라 보호되는 저작물에 관하여 본국 이외의 동맹국에서 각 법률이 현재 또는 장래에 자국민에게 부여하는 권리 및 이 협약이 특별히 부여하는 권리를 향유한다고 규정하여 내국민대우원칙을 천명하고 있다. 또한 베른협약 제5조 제2항은 저작권의 보호와 향유는 저작물의 본국에서 보호가 존재하는 여부와 관계가 없이, 보호의 범위와 저작자의 권리를 보호하기 위하여 주어지는 구제의 방법은 오로지 보호가 주장되는 국가의 법률의 지배를 받는다라고 규정하여 저작권 침해가 발행한 국가의 법률의 적용을 명시하고 있다. 인터넷과 무선통신 기술의 발달은 저작물을 디지탈 형식으로 실시간에 전세계에 배포하는 것을 가능하게 하였다. 특히 저작물의 인터넷상에서의 배포는 다국적 저작권 침해행위를 야기하여, 저작권자가 다수의 국가에서 저작권 침해소송을 제기하여 판결을 집행하는 것이 필요하게 되었다. 헤이그국제사법회의(Hague Conference on Private International Law)에서 1992년부터 논의되어 온 민사 및 상사사건의 국제재판관할과 외국판결에 관한 협약(Convention on Jurisdiction and Foreign Judgment in Civil and Commercial Matters)에서 채택된1999년의 예비초안(preliminary draft) 및 2001년 외교회의에서 수정된 잠정초안(Interim text) (이하 헤이그 협약 )은 저작권자가 저작권침해행위가 발생한 각 국가에서 저작권 침해행위를 금지하는 소송을 제기할 필요없이, 동 협약의 한 가맹국가의 법원의 저작권침해금지판결을 다른 가맹국가에서도 집행할 수 있는 가능성을 제시해 주는데 의미가 있다. 헤이그 협약 제10조는 불법행위(torts)에 관한 일반적인 재판관할에 관한 규정을 두고 있으며, 저작권침해에 관한 분쟁은 동 조항의 적용을 받는다. 제10조에 의해 당사자는 가해행위지 국가의 법원 또는 결과발생지 국가의 법원에서 소송을 제기할 수 있다. 결과발생지의 경우 제10조 1항 (b)는 피고가 자신의 행위가 본국의 법규에 비추어 동일한 성격의 손해를 초래할 수 있다라고 합리적으로 예견할 수 없었던 경우에 본 조항의 적용을 배제하고 있다. 인터넷을 통한 저작권침해의 경우, 피고가 자신의 국가의 법규하에서 합법적으로 저작물을 웹사이트에 게시하였으나, 그 행위가 다운로딩이 행해진 국가에서 불법인 경우, 피고는 저작권침해를 예견할 수 없었으므로 이에 문제가 제기된다. iCrave TV사건에서, 피고인 캐나다회사가 미국 및 캐나다에서 방송되는 텔레비젼 방송 프로그램을 자신의 웹사이트에 게시하여 이용자들로 하여금 컴퓨터를 통하여 방송을 재시청 할 수 있도록 하였는데 이는 캐나다에서 합법인 반면에 미국에서는 저작권 침해에 해당한다. 피고는 방송 프로그램을 인터넷상에서 재방송하는 것은 캐나다법상 합법이므로 저작권침해를 예견할 수 없었다고 주장하면서, 해당 사이트에 오직 캐나다 거주자만의 접속을 허용하고 미국 거주자의 접속을 제한하는 일련의 Click-Wrap 계약과 스크린 장치를 제공하였다고 주장하였다. 본 사건 피고의 주장을 받아들인다고 가정할 때, 제10조 1항(b)에 의해 원고는 결과발생지인 미국법원의 재판관할을 강제할 수 없을 것이다. 지적재산권을 둘러싼 분쟁에 관한 재판관할과 국제법상의 판결의 승인 및 집행의 통일성을 기하기 위하여 2001년 1월 세계지적재산권기구(World Intellectual Property Organization)가 제안한 WIPO 협약초안(Draft Convention on Jurisdiction and Recognition of Judgments in Intellectual Property Matters)은 헤이그 협약이 재판관할과 판결의 승인 및 집행에 대한 일반적인 접근을 하고 있는 점에 반하여 지적재산권자의 보호라는 측면을 고려하여 지적재산권침해소송에 국제재판관할권을 규정하고 있다. WIPO 협약초안 제6조는 저작권자가 저작권 침해를 막기 위한 합리적인 조치를 취한 국가에서 저작권 침해소송을 피할 수 있다고 규정하고 있다. 따라서 본 조항에 의할 경우, iCrave TV사건의 피고는 미국에서의 저작권 침해소송을 회피할 수 있을 것이다. 이상과 같이 헤이그 협약이 외국판결의 승인 및 집행을 가능하게 하고 있음에도 불구하고, 외국법원의 판결이 다수의 가맹국가에서 집행되지 못하는 가장 큰 장애는 대다수의 국가들이 외국법원의 판결이 공서양속(Public Policy)에 반하는 경우 판결을 승인하지 않는 예외규정을 두고 있기 때문이다. 미국의 경우, Uniform Recognition Act와 Restatement(Third) of Foreign Relations에 따른 공서양속의 예외규정(Public Policy exception)은 외국법원의 판결의 승인을 부인하는 근거가 된다. Yahoo! 사건에서 Yahoo! Inc.의 옥션 사이트를 통해 독일 나치 소장물의 판매가 이루어졌는데, 프랑스 형법상 이는 범죄행위에 해당하므로, 프랑스 법원은Yahoo! Inc.에게 프랑스 이용자가 당해 옥션 사이트에 접속할 수 없도록 모든 가능한 조치를 취할 것을 명하였다. 이에 미국 법원은 프랑스 법원의 판결은 Yahoo! Inc.의 미국헌법 제1 수정(First Amendment)의 언론의 자유(freedom of speech)에 반하므로 판결의 집행을 거부하였는데 이는 공서양속의 예외규정을 보여주는 예이다. 헤이그 협약 제28조와 WIPO 협약초안 제25조 또한 공서양속의 예외규정을 두고 있다. 본 논문은 인터넷과 통신기술의 발달로 야기되는 다국적 저작권 침해사건에서 한 국가의 법원의 저작권 침해금지판결이 다수의 국가에서 승인 및 집행될 수 있는 능성을 헤이그 협약과 WIPO 협약초안 및 미국판결을 중심으로 살펴보았다. 국제적으로 통일된 저작권법이 존재하지 않고 외국 판결의 승인을 부인하는 예외조항과 외국판결의 집행에 관한 각국의 이해관계와 준거법의 해석이 다른 현시점에서 지적재산권의 속지주의를 뛰어넘어 외국법원의 판결을 국제적으로 집행하는 것은 다소 어려움이 있어 보이나 국제적인 집행가능성의 열쇠를 제시하는 헤이그 협약과 장래의 국제조약에 그 기대를 걸어볼 수 있겠다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.2
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• pp.125-132
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• 1990

The authors carried out an experiment to investigate the responsive behavior of sea eel, Astroconger myriaster(BREVOORT) to chemical stimuli. The experimental tank was made in doughnut type by using FRP plates. The channel of tank was divided into three concentric troughs by using perforated plastic plates. The inside trough was used as influent part, the outside one as effluent part, and the middle one as the testing trough in which testing fish may be swimmable. The influent part was radially portioned into 12 sections so as to be 30 degrees of central angle. But a basin of any section in testing trough was diverged in the range of 45 degrees of central angle. The the testing trough are radially divided into eight zones. Water is supplied at the rate of 6.3l per minute from the central water tank set as high as 50cm in the center of doughnut, passed across the influent part, testing trough, effluent part and finally discharged by overflow pipes. The chemical substance to stimulate the sea eel was extracted from mackerel, shad and krill which are used as bait for fishing. The chemical substance was injected into any one of 12 hoses which supplies water from central water tank to the influent part at the rate of 2ml per minute. Sea eels used for the experiment were caught by pot in the coast of Chung-mu and accustomed to the tanks for 5 days before applying them to the experiment. The result obtained are as follows: 1. The rate of time length of sea eel's staying in the stimulated zone, as the extracts of mackerel, shad and krill were given to it, was observed as 7.9%, 30.9% and 11.4% respectively. It means that the extract from shad was the most effective of three in attracting sea eel. 2. To compare the effect of freshness of bait fish, the extracts were prepared from shad just killed, form the 24 hour-lapsed one and from the 48 hour-lasped one after killed. The rate of time length of sea eel's staying in the stimulated zone was 30.9%, 17.1% and 11.3% respectively. It means that the freshness is much effective in attracting olfactory fishes like sea eel.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.77-93
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• 2000

Field survey on the spatio-temporal distribution of water quality and chlorophyll a concentration, and the environmental factors on the variation of phytoplankton biomass were carried out at the 23 stations for four seasons in the Shiahae, southwestern coast of Korean Peninsula from February to October in 1995. I made an analysis on biological factor as chlorophyll a concentration as well as environmental factors such as water temperature, salinity and nutrients; ammonia, nitrite, nitrate, dissolved inorganic nitrogen, phosphate, N/P ratio, silicate and Si/P ratio. The waters in the Shiahae were not stratified due to the tidal mixing and high velocity of tidal current. And the high productivity in photic layer were supported by high nutrients concentration from freshwater on lands and bottom waters The low depth of transparency in the Shiahae had a bad influence upon primary production and marine biology. In Shiahae had a sufficient nutrients for primary production during a year. Especially dissolved inorganic nitrogen and silicate were high, the other side, phosphate was low. The source of nutrients in summer and silicate supply depend on input of freshwater from lands, the other side, dissolved inorganic nitrogen and phosphate were depend on rather supplied from bottom layer by the mixing and input of seawater from outside than input of freshwater from lands. Phosphate seemed to become a limiting nutrient for the primary production at all area of Shiahae in winter and at the northern parts in other seasons. However, dissolved inorganic nitrogen seemed to do it at the southern parts in other seasons except winter. Silicate didn't become a limiting nutrient for diatoms in Shiahae. Phytoplankton biomass as measured by chlorophyll a concentration was very high all the year round, it was controlled by the combination of the several environmental factors, especially of nitrogen, phosphorus and the physical factors such as light intensity. [Spatio-temporal distribution, Seasonal fluctuation, Nnutrients, Chlorophyll a, Environmental factors, Nutrient source, Limiting Nutrient, Light, Shiahae] .

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.57-73
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• 2008

Nitrate concentrations were measured up to 49 mg/L (as $NO_3$-N) and 22% of the samples exceeded drinking water standard in shallow and bedrock groundwater of the northern Nonsan area. Nitrate concentrations showed a significant difference among land use groups. To predict nitrate concentration in groundwater, multiple regression analysis was carried out using hydrogeologic parameters of soil media, topography and land use which were categorized as several groups, well depth and altitude, and field parameters of temperature, pH, DO and EC. Hydrogeologic parameters were quantified as area proportions of each category within circular buffers centering at wells. Regression was performed to all the combination of variables and the most relevant model was selected based on adjusted coefficient of determination (Adj. $R^2$). Regression using hydrogelogic parameters with varying buffer radii show highest Adj. $R^2$ at 50m and 300m for shallow and bedrock groundwater, respectively. Shallow groundwater has higher Adj. $R^2$ than bedrock groundwater indicating higher susceptibility to hydrogeologic properties of surface environment near the well. Land use and soil media was major explanatory variables for shallow and bedrock groundwater, respectively and residential area was a major variable in both shallow and bedrock groundwater. Regression involving hydrogeologic parameters and field parameters showed that EC, paddy and pH were major variables in shallow groundwater whereas DO, EC and natural area were in bedrock groundwater. Field parameters have much higher explanatory power over the hydrogeologic parameters suggesting field parameters which are routinely measured can provide important information on each well in assessment of nitrate contamination. The most relevant buffer radii can be applied to estimation of travel time of contaminants in surface environment to wells.