• Title/Summary/Keyword: High Seas

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Benthic Macroinvertebrates Inhabiting Estuaries in Sea Area and Relationship with Major Drivers of Change in Estuaries (해역별 하구에 서식하는 저서성 대형무척추동물 현황과 하구 서식지 주요 변화 동인과의 관계)

  • Lim, Sung-Ho;Jung, Hyun-Chul;Lee, Min-Hyuk;Lee, Sang-Wook;Moon, Jeong-Suk;Kwon, Soon-Hyun;Won, Du-Hee
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.10-18
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    • 2022
  • This study analyzed the relationship between the community structure of benthic macroinvertebrates and habitat changes in open estuaries among the sites included in the national estuary monitoring program. The estuary survey was conducted under the "Guidelines for Investigation and Evaluation of Biometric Networks" and classified by sea area, 80 places in the East Sea, 102 places in the South Sea, and 19 places in the West Sea were investigated. In a total of 201 open estuaries, benthic macroinvertebrates were identified with 4 phyla, 9 classes, 41 orders, 139 families, 269 species and 196 species in the East Sea, 182 species in the South Sea, and 90 species in the West Sea. The highest population densities were Insecta in the East Sea, the Malacostraca in the South Sea, and the Annelida in the West Sea. Through SIMPER analysis, species contributing to the similarity of benthic macroinvertebrates communities in each sea area were identified. Some species greatly influenced the similarity of clusters. The benthic community in the East Sea was affected by the salinity, so the contribution rate of freshwater species was high. On the other hand, the benthic communities of the South and West Seas showed species compositions are influenced by the substrate composition. As results, the benthic macroinvertebrate community in Korean estuaries was impacted by salinity and substrate simultaneously, and the close relationship with geographical distance was not observed. The result of this study is expected to be used to respond to environmental changes by identifying and predicting changes in the diversity and distribution of benthic macroinvertebrates in Korea estuaries.

Stock Identification of Todarodes pacificus in Northwest Pacific (북서태평양에 서식하는 살오징어(Todarodes pacificus) 계군 분석에 대한 고찰)

  • Kim, Jeong-Yun;Moon, Chang-Ho;Yoon, Moon-Geun;Kang, Chang-Keun;Kim, Kyung-Ryul;Na, Taehee;Choy, Eun Jung;Lee, Chung Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.4
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    • pp.292-302
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    • 2012
  • This paper reviews comparison analysis of current and latest application for stock identification methods of Todarodes pacificus, and the pros and cons of each method and consideration of how to compensate for each other. Todarodes pacificus which migrates wide areas in western North Pacific is important fishery resource ecologically and commercially. Todarodes pacificus is also considered as 'biological indicator' of ocean environmental changes. And changes in its short and long term catch and distribution area occur along with environmental changes. For example, while the catch of pollack, a cold water fish, has dramatically decreased until today after the climate regime shift in 1987/1988, the catch of Todarodes pacificus has been dramatically increased. Regarding the decrease in pollack catch, overfishing and climate changes were considered as the main causes, but there has been no definite reason until today. One of the reasons why there is no definite answer is related with no proper analysis about ecological and environmental aspects based on stock identification. Subpopulation is a group sharing the same gene pool through sexual reproduction process within limited boundaries having similar ecological characteristics. Each individual with same stock might be affected by different environment in temporal and spatial during the process of spawning, recruitment and then reproduction. Thereby, accurate stock analysis about the species can play an efficient alternative to comply with effective resource management and rapid changes. Four main stock analysis were applied to Todarodes pacificus: Morphologic Method, Ecological Method, Tagging Method, Genetic Method. Ecological method is studies for analysis of differences in spawning grounds by analysing the individual ecological change, distribution, migration status, parasitic state of parasite, kinds of parasite and parasite infection rate etc. Currently the method has been studying lively can identify the group in the similar environment. However It is difficult to know to identify the same genetic group in each other. Tagging Method is direct method. It can analyse cohort's migration, distribution and location of spawning, but it is very difficult to recapture tagged squids and hard to tag juveniles. Genetic method, which is for useful fishery resource stock analysis has provided the basic information regarding resource management study. Genetic method for stock analysis is determined according to markers' sensitivity and need to select high multiform of genetic markers. For stock identification, isozyme multiform has been used for genetic markers. Recently there is increase in use of makers with high range variability among DNA sequencing like mitochondria, microsatellite. Even the current morphologic method, tagging method and ecological method played important rolls through finding Todarodes pacificus' life cycle, migration route and changes in spawning grounds, it is still difficult to analyze the stock of Todarodes pacificus as those are distributed in difference seas. Lately, by taking advantages of each stock analysis method, more complicated method is being applied. If based on such analysis and genetic method for improvement are played, there will be much advance in management system for the resource fluctuation of Todarodes pacificus.

An Analysis on the Conditions for Successful Economic Sanctions on North Korea : Focusing on the Maritime Aspects of Economic Sanctions (대북경제제재의 효과성과 미래 발전 방향에 대한 고찰: 해상대북제재를 중심으로)

  • Kim, Sang-Hoon
    • Strategy21
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    • s.46
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    • pp.239-276
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    • 2020
  • The failure of early economic sanctions aimed at hurting the overall economies of targeted states called for a more sophisticated design of economic sanctions. This paved way for the advent of 'smart sanctions,' which target the supporters of the regime instead of the public mass. Despite controversies over the effectiveness of economic sanctions as a coercive tool to change the behavior of a targeted state, the transformation from 'comprehensive sanctions' to 'smart sanctions' is gaining the status of a legitimate method to impose punishment on states that do not conform to international norms, the nonproliferation of weapons of mass destruction in this particular context of the paper. The five permanent members of the United Nations Security Council proved that it can come to an accord on imposing economic sanctions over adopting resolutions on waging military war with targeted states. The North Korean nuclear issue has been the biggest security threat to countries in the region, even for China out of fear that further developments of nuclear weapons in North Korea might lead to a 'domino-effect,' leading to nuclear proliferation in the Northeast Asia region. Economic sanctions had been adopted by the UNSC as early as 2006 after the first North Korean nuclear test and has continually strengthened sanctions measures at each stage of North Korean weapons development. While dubious of the effectiveness of early sanctions on North Korea, recent sanctions that limit North Korea's exports of coal and imports of oil seem to have an impact on the regime, inducing Kim Jong-un to commit to peaceful talks since 2018. The purpose of this paper is to add a variable to the factors determining the success of economic sanctions on North Korea: preventing North Korea's evasion efforts by conducting illegal transshipments at sea. I first analyze the cause of recent success in the economic sanctions that led Kim Jong-un to engage in talks and add the maritime element to the argument. There are three conditions for the success of the sanctions regime, and they are: (1) smart sanctions, targeting commodities and support groups (elites) vital to regime survival., (2) China's faithful participation in the sanctions regime, and finally, (3) preventing North Korea's maritime evasion efforts.

A study on Operation Rules of Korean Air Defence Identification Zone (한국 방공식별구역 운영규칙에 관한 고찰)

  • Kwon, Jong-Pil;Lee, Yeong H.
    • The Korean Journal of Air & Space Law and Policy
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    • v.32 no.2
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    • pp.189-217
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    • 2017
  • Declaration of Air Defense and Identification Zones started with the United States in 1950, which was followed by declaration of KADIZ by the Republic of Korea in 1951. Initial ADIZ were solely linked with air defense missions, but their roles have changed as nations around the globe manifested a tendency to expand their influence over maritime resources and rights. In particular, China declared ADIZ over the East China Sea in October 2013 and forced all passing aircraft to submit flight plan to ATC or military authority, saying failure of submission will be followed by armed engagement. China announced it would declare another zone over the South China Sea despite the ongoing conflict in the area, clearly showing ADIZ's direct connection with territorial claim and EEZ and that it serves as a zone within which a nation can execute its rights. The expanded KADIZ, which was expanded in Dec 15, 2013 in response to Chinese actions, overlaps with the Chinese ADIZ over the East China Sea and the Japanese ADIZ. The overlapping zone is an airspace over waters where not only the Republic of Korea but also of China and Japan argue to be covering their continental shelf and EEZ. Military conventions were signed to prevent contingencies among the neighboring nations while conducting identifications in KADIZ, including the overlapping zone. If such military conventions and practice of air defense identification continue to be respected among states, it is under the process of turning into a regional customary law, although ADIZ is not yet recognized by international law or customary law. Moreover, identification within ADIZ is carried out by military authorities of states, and misguided customary procedures may cause serious negative consequences for national security since it may negatively impact neighboring countries in marking the maritime border, which calls for formulation of operation rules that account for other state activities and military talks among regional stake holders. Legal frameworks need to be in place to guarantee freedom of flights over international seas which UN Maritime Law protects, and laws regarding military aircraft operation need to be supplemented to not make it a requirement to submit flight plan if the aircraft does not invade sovereign airspace. Organizational instructions that require approval of Chairman of Joint Chiefs of Staff for entrance and exit of ADIZ for military aircraft need to be amended to change the authority to Minister of National Defense or be promoted to a law to be applicable for commercial aircraft. Moreover, in regards to operation and management of ADIZ, transfer of authority should be prohibited to account for its evolution into a regional customary law in South East Asia. In particular, since ADIZ is set over EEZ, military conventions that yield authority related to national security should never be condoned. Among Korea, China, Japan and Russia, there are military conventions that discuss operation and management of ADIZ in place or under negotiation, meaning that ADIZ is becoming a regional customary law in North East Asia region.

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A Study on the Meaning and Future of the Moon Treaty (달조약의 의미와 전망에 관한 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.21 no.1
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    • pp.215-236
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    • 2006
  • This article focused on the meaning of the 1979 Moon Treaty and its future. Although the Moon Treaty is one of the major 5 space related treaties, it was accepted by only 11 member states which are non-space powers, thus having the least enfluences on the field of space law. And this article analysed the relationship between the 1979 Moon Treay and 1967 Space Treaty which was the first principle treaty, and searched the meaning of the "Common Heritage of Mankind(hereinafter CHM)" stipulated in the Moon treaty in terms of international law. This article also dealt with the present and future problems arising from the Moon Treaty. As far as the 1967 Space Treaty is concerned the main standpoint is that outer space including the moon and the other celestial bodies is res extra commercium, areas not subject to national appropriation like high seas. It proclaims the principle non-appropriation concerning the celestial bodies in outer space. But the concept of CHM stipulated in the Moon Treaty created an entirely new category of territory in international law. This concept basically conveys the idea that the management, exploitation and distribution of natural resources of the area in question are matters to be decided by the international community and are not to be left to the initiative and discretion of individual states or their nationals. Similar provision is found in the 1982 Law of the Sea Convention that operates the International Sea-bed Authority created by the concept of CHM. According to the Moon Treaty international regime will be established as the exploitation of the natural resources of the celestial bodies other than the Earth is about to become feasible. Before the establishment of an international regime we could imagine moratorium upon the expoitation of the natural resources on the celestial bodies. But the drafting history of the Moon Treaty indicates that no moratorium on the exploitation of natural resources was intended prior to the setting up of the international regime. So each State Party could exploit the natural resources bearing in mind that those resouces are CHM. In this respect it would be better for Korea, now not a party to the Moon Treaty, to be a member state in the near future. According to the Moon Treaty the efforts of those countries which have contributed either directly or indirectly the exploitation of the moon shall be given special consideration. The Moon Treaty, which although is criticised by some space law experts represents a solid basis upon which further space exploration can continue, shows the expression of the common collective wisdom of all member States of the United Nations and responds the needs and possibilities of those that have already their technologies into outer space.

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A Study on the Meaning of Outer Space Treaty in International Law (우주조약의 국제법적 의미에 관한 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.223-258
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    • 2013
  • 1967 Outer Space Treaty(Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies; OST) is a treaty that forms the basis of international space law. OST is based on the 1963 Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space announced by UNGA resolution. As of May 2013, 102 countries are states parties to OST, while another 27 have signed the treaty but have not completed ratification. OST explicitly claimed that the Moon and Other Celestial Bodies are the province of all mankind. Art. II of OST states that "outer space, including the Moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means", thereby establishing res extra commercium in outer space like high seas. However 1979 Moon Agreement stipulates that "the moon and its natural resources are the Common Heritage of Mankind(CHM)." Because of the number of the parties to the Moon Agreement(13 parties) it does not affect OST. OST also established its specific treaties as a complementary means such as 1968 Rescue Agreement, 1972 Liability Convention, 1975 Registration Convention. OST bars states party to the treaty from placing nuclear weapons or any other weapons of mass destruction in orbit of Earth, installing them on the Moon or any other celestial body, or to otherwise station them in outer space. It exclusively limits the use of the Moon and other celestial bodies to peaceful purposes and expressly prohibits their use for testing weapons of any kind, conducting military maneuvers, or establishing military bases, installations, and fortifications. However OST does not prohibit the placement of conventional weapons in orbit. China and Russia submitted Draft Treaty on the Prevention of the Placement of Weapon in Outer Space and of the Threat or Use of Force against Outer Space Objects(PPWT) on the Conference on Disarmament in 2008. USA disregarded PPWT on the ground that there are no arms race in outer space. OST does not have some articles in relation to current problems such as space debris, mechanisms of the settlement of dispute arising from state activities in outer space in specific way. COPUOS established "UN Space Debris Mitigation Guidelines" based on "IADC Space Debris Mitigation Guidelines" and ILA proposed "International Instrument on the Protection of the Environment from Damage Caused by Space Debris" for space debris problems and Permanent Court of Arbitration(PCA) established "Optional Rules for Arbitration of Disputes Relating to Outer Space Activities" and ILA proposed "1998 Taipei Draft Convention on the Settlement of Space Law Dispute" for the settlement of dispute problems. Although OST has shortcomings in some articles, it is very meaningful in international law in considering the establishment of basic principles governing the activities of States in the exploration and use of outer space, including the Moon and Other Celestial Bodies. OST established the principles governing the activities of states in the exploration and use of outer space as customary law and jus cogens in international law as follows; the exploration and use of outer space shall be carried out for the benefit and in the interests of all countries and shall be the province of all mankind; outer space shall be free for exploration and use by all States; outer space is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means. The principles of global public interest in outer space imposes international obligations erga omnes applicable to all States. This principles find significant support in legal norms dealing with following points: space activities as the "province of all mankind"; obligation to cooperate; astronauts as envoys of mankind; avoidance of harmful contamination; space activities by States, private entities and intergovernmental organisations; absolute liability for damage cauesd by certain space objects; prohibition of weapons in space and militarization of the celestial bodies; duty of openness and transparency; universal application of the international space regime.

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A Study on the Effective Independent Study of Nursing Student (간호학생의 효과적인 자율학습을 위한 조사연구)

  • 김광주;이향련
    • Journal of Korean Academy of Nursing
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    • v.8 no.1
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    • pp.16-42
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    • 1978
  • This survey was made for a month starting from November 15 to December 15, 1977 covering 711 students taking the junior. (3rd-yea.) and the senior. (4th-year) at nine college of nursing in Seoul concerning their perception and Attitude toward the profession of nursing, motive for the necessity of learning, environment of study, attitude of study and particulars relevant with study performance, particulars of library, references and reading, assignments and particulars of the degree of confidence for the learning achievement. Through the survey of the above Particulars, the following results were obtained by classifying all subject matters and by analysing motive of the selection of their course, awarding or not awarding of scholarships. 1. General characteristics: it was revealed that 406 students (57.1%) were attending at the junior. while 305 students (42.9%) were taking the senior. Thus, the total number was 711 and their average age was 21.4 years. Their dwelling category was; 73.9 percent of them resided at their parent's home, 214 students (30.1%) were awarded with scholarships. The reason to be attracted by nursing science was the possibility of continuing social life after graduation (43.5%). 2. Their perception and attitude toward the profession of nursing: According to the perception of profession by the students of each grade, students of the 4th grade showed comparatively strong conception. Also, students of the 4th grade showed more positive attitude in the purchase and reading of magazines relative with the science of nursing, in the reading of Code for Nurses and in their interest in the activity of nursing field. For the necessity of mission of nurse, 97.7 percent of the entire number of students covered responded to necessity. For the necessity of the particular humanity and particularity in the character of nurses, 95.8 percent of those students responded to necessity. By the each grade, students of the 4th grade showed more response. 3. As to professional field desired after completing the professional course: 57 percent of those students desired for clinician nurse while 55 percents desired for community health-nurse. 4. As to the environment of study: they were mostly satisfied with their present residential environment. However, they complained of inconvenience at their lecture-halls. Students of the 3rd grade showed more complain. As to their attitude toward the adjustment of environment of study, they showed a affirmative response. As to the opinion of factors which interfere with their study, comparatively strong response was showed in their scepticism in the science of nursing, insufficient comprehension in general learning, relation with professors n4 discrepancy in the method of study. According to opinions of students at each grade, students of the 4th grade showed more scepticism. 5. Particulars relative with their attitude and performance of study : As to their knowledge of the objectives of their study of subject, the majority was to study with a partial knowledge of the objectives of their study. As to the plan of study, a low percentage indicated management of routine life under regular scheduling. Students of the 4th grade responded to rather planned life. As to time spent in independent study, response to concentrated study when necessary was stronger than that to regular daily study. Students of the 4th grade showed stronger response to regular study than that of the 3rd grade. As to the contents of their note-taking, 67.4 percents of those students responded to such regulatory procedure performing in the lecture-hall as they listen to lectures. 17.3 percents of those students showed response to adding supplementary informations from references to what was entered in choir note-taking at their lecture-halls. 6. Particulars of library, references and reading books: As to receiving of instruction for the utilization of library and time of receiving such instruction 64.7 percents of those students had received such instruction. 66.7 percents of the those responded received such instruction at orientation conducted for freshmen. As to the convenience of the utilization of library, 49.9 percents of those students responded to convenience. However, students of the 3rd grade showed a much stronger response to inconvenience. As to the time of the utilization of library,92.5 percents of those students showed a response to occasional utilization for particular purpose than regular utilization. 53.2 percents of those students responded to ordinary in quantity that library have references. 34.2 percents of those students responded to insufficient. As to the particular relative with the method and field of reading: 53.5 percents of those students responded to intensive reading and was the majority. As to the reading field, fiction u as the majority. When read any books for their major, they usually rend Korean text-b, oks. 7. Particular relative with giving assignment: All respondents were well aware of the objectives of giving home tasks. As to the attitude toward assignments and performing home tasks, 54.8 percents of those students to making ostentatious study because of an excessive quantity of assignments imposed. For performing assignment, they showed comparatively positive response. Also, 52.2 percents of those students responded that they usually submitted complected assignment with references. 8. As to motive to realize the necessity of study : 55.6 percents of those students responded that they realized such necessity in communication with patients when they were engaged in clinical practice. Also, 8.6, the lowest percents of those students responded that they realized such necessity in the course of conversation with nurses when they were engaged in clinical practice. 9. As to the determination of their confidence in the performance of study relative with clinical experience: They showed a general inclination of having in nursing. The major response was that they came to well comprehend the patients families. the lowest response was that they could apply what was learned at lecture-hall to practice. This response incidentally showed the distance the lecture-hall and practical study. In general items, students of the 4th grade showed more favorable response than students of the 3rd grade and there was a significant difference. 10. As to the perception and attitude toward profession according to the motive of selecting the nursing science : Those who selected the nursing voluntarily showed stronger conception than those who selected the nursing through indirect influence. However, there was no significant difference on this point. Only there was a remarkable difference in the reading of Code for Nurses. 11. Those who showed a stronger conception in the profession of nursing according to the motives of attractive nursing science indicated a strong will and ability to manage stable life and comparatively strong response was shown in the management of good home life because of the good adaptability of the science to their character. This group showed a strong conception of the profession than those who responded that they prefer this profession out of a longing for the work of a hospital and for the easy obtaining of opportunity to immigrate to over seas and for economic cause and for high school grade. There was significant difference between these two groups, 12. As to the conception and attitude toward the profession of nursing according to benefits by scholarships, those who were benefitted by scholarship showed stronger conception of profession than those who did not receive scholarship and there was a remarkable difference between these two categories. However, there was no remarkable difference between these two categories in the extent of interest of the activities of nursing fields and in the reading of Code for Nurses. 13. As activation for study according to the benefits of scholarships, those who were benefitted by scholarships showed stronger response to the motive for study comparing with those who receive. 14. As to tile field of reading according to the benefits by scholarships, those who received scholarships tended to read autobiographies and essayers to a considerable extent. Those who did not receive scholarships tended to read novels. Those who received scholarships more read nursing boots than those who did not receive scholarships. 15. As to the attitude of study and doing of assignment according to benefits of scholarships, those who received scholarships managed a favorable life with schedules for study, More students of receiving scholarship showed a regular study for more than one hour per day. Also, in the method of doing home tasks, more students of receiving scholarship showed reference to relative books frequently for the submission of completed assignments.

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Studies on the Consumptine Use of Irrigated Water in Paddy Fields During the Growing of Rice Plants(III) (벼생유기간중의 논에서의 분석소비에 관한 연구(II))

  • 민병섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.11 no.4
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    • pp.1775-1782
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    • 1969
  • The results of the study on the consumptine use of irrigated water in paddy fields during the growing season of rice plants are summarized as follows. 1. Transpiration and evaporation from water surface. 1) Amount of transpiration of rice plant increases gradually after transplantation and suddenly increases in the head swelling period and reaches the peak between the end of the head swelling poriod and early period of heading and flowering. (the sixth period for early maturing variety, the seventh period for medium or late maturing varieties), then it decreases gradually after that, for early, medium and late maturing varieties. 2) In the transpiration of rice plants there is hardly any difference among varieties up to the fifth period, but the early maturing variety is the most vigorous in the sixth period, and the late maturing variety is more vigorous than others continuously after the seventh period. 3) The amount of transpiration of the sixth period for early maturing variety of the seventh period for medium and late maturing variety in which transpiration is the most vigorous, is 15% or 16% of the total amount of transpiration through all periods. 4) Transpiration of rice plants must be determined by using transpiration intensity as the standard coefficient of computation of amount of transpiration, because it originates in the physiological action.(Table 7) 5) Transpiration ratio of rice plants is approximately 450 to 480 6) Equations which are able to compute amount of transpiration of each variety up th the heading-flowering peried, in which the amount of transpiration of rice plants is the maximum in this study are as follows: Early maturing variety ; Y=0.658+1.088X Medium maturing variety ; Y=0.780+1.050X Late maturing variety ; Y=0.646+1.091X Y=amount of transpiration ; X=number of period. 7) As we know from figure 1 and 2, correlation between the amount evaporation from water surface in paddy fields and amount of transpiration shows high negative. 8) It is possible to calculate the amount of evaporation from the water surface in the paddy field for varieties used in this study on the base of ratio of it to amount of evaporation by atmometer(Table 11) and Table 10. Also the amount of evaporation from the water surface in the paddy field is to be computed by the following equations until the period in which it is the minimum quantity the sixth period for early maturing variety and the seventh period for medium or late maturing varieties. Early maturing variety ; Y=4.67-0.58X Medium maturing variety ; Y=4.70-0.59X Late maturing variety ; Y=4.71-0.59X Y=amount of evaporation from water surface in the paddy field X=number of period. 9) Changes in the amount of evapo-transpiration of each growing period have the same tendency as transpiration, and the maximum quantity of early maturing variety is in the sixth period and medium or late maturing varieties are in the seventh period. 10) The amount of evapo-transpiration can be calculated on the base of the evapo-transpiration intensity (Table 14) and Tablet 12, for varieties used in this study. Also, it is possible to compute it according to the following equations with in the period of maximum quantity. Early maturing variety ; Y=5.36+0.503X Medium maturing variety ; Y=5.41+0.456X Late maturing variety ; Y=5.80+0.494X Y=amount of evapo-transpiration. X=number of period. 11) Ratios of the total amount of evapo-transpiration to the total amount of evaporation by atmometer through all growing periods, are 1.23 for early maturing variety, 1.25 for medium maturing variety, 1.27 for late maturing variety, respectively. 12) Only air temperature shows high correlation in relation between amount of evapo-transpiration and climatic conditions from the viewpoint of Korean climatic conditions through all growing periods of rice plants. 2. Amount of percolation 1) The amount of percolation for computation of planning water requirment ought to depend on water holding dates. 3. Available rainfall 1) The available rainfall and its coefficient of each period during the growing season of paddy fields are shown in Table 8. 2) The ratio (available coefficient) of available rainfall to the amount of rainfall during the growing season of paddy fields seems to be from 65% to 75% as the standard in Korea. 3) Available rainfall during the growing season of paddy fields in the common year is estimated to be about 550 millimeters. 4. Effects to be influenced upon percolation by transpiration of rice plants. 1) The stronger absorbtive action is, the more the amount of percolation decreases, because absorbtive action of rice plant roots influence upon percolation(Table 21, Table 22) 2) In case of planting of rice plants, there are several entirely different changes in the amount of percolation in the forenoon, at night and in the afternoon during the growing season, that is, is the morning and at night, the amount of percolation increases gradually after transplantation to the peak in the end of July or the early part of August (wast or soil temperature is the highest), and it decreases gradually after that, neverthless, in the afternoon, it decreases gradually after transplantation to be at the minimum in the middle of August, and it increases gradually after that. 3) In spite of the increasing amount of transpiration, the amount of daytime percolation decreases gadually after transplantation and appears to suddenly decrease about head swelling dates or heading-flowering period, but it begins to increase suddenly at the end of August again. 4) Changs of amount of percolation during all growing periods show some variable phenomena, that is, amount of percolation decreases after the end of July, and it increases in end August again, also it decreases after that once more. This phenomena may be influenced complexly from water or soil temperature(night time and forenoon) as absorbtive action of rice plant roots. 5) Correlation between the amount of daytime percolation and the amount of transpiration shows high negative, amount of night percolation is influenced by water or soil temperature, but there is little no influence by transpiration. It is estimated that the amount of a daily percolation is more influenced by of other causes than transpiration. 6) Correlation between the amount of night percoe, lation and water or soil temp tureshows high positive, but there is not any correlation between the amount of forenoon percolation or afternoon percolation and water of soil temperature. 7) There is high positive correlation which is r=+0.8382 between the amount of daily percolation of planting pot of rice plant and amount and amount of daily percolation of non-planting pot. 8) The total amount of percolation through all growin. periods of rice plants may be influenced more from specific permeability of soil, water of soil temperature, and otheres than transpiration of rice plants.

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