• 제목/요약/키워드: Spring Season

검색결과 1,325건 처리시간 0.028초

한국 활엽수림의 이산화탄소 농도의 연직구조와 저류항 (Vertical Profiles of CO2 Concentrations and CO2 Storage in Temperate Forest in Korea)

  • ;강민석;천정화;김준
    • 한국농림기상학회:학술대회논문집
    • /
    • 한국농림기상학회 2013년도 추계 학술발표논문집
    • /
    • pp.23-24
    • /
    • 2013
  • Micrometeorological fluxes measured over a tall forest in a complex terrain are difficult to interpret. $CO_2$ storage often makes significant contributions to net ecosystem exchange of $CO_2$ (NEE) in early morning and during nighttime due to calm and stable conditions. We measured the above-canopy $CO_2$ flux along with its concentration profiles at eight levels within and above the canopy to evaluate $CO_2$ storage term. Our question is whether or not the $CO_2$ storage term can be estimated accurately from a single level measurement of $CO_2$ concentration in a complex terrain. Our objectives are (1) to document vertical profiles of $CO_2$ concentration and (2) to compare the diurnal and seasonal variations of $CO_2$ storages estimated from single and multi-level $CO_2$ concentration data. Seasonally averaged Diurnal variations of $CO_2$ concentration ranged from 398 to 455 ppm near the forest floor at 0.1 m whereas they ranged from 364 to 395 ppm at 40 m in the atmosphere. The diurnal variation of vertical profiles of $CO_2$ concentration shows very interesting features with season. At all eight levels, diurnal variation of $CO_2$ concentration showed little change in winter. In spring, the diurnal variations of $CO_2$ concentration at 8 levels showed three distinct groups of layers with height: the first layer: 0.1m (near surface), second layer: 1.0 m and 4.0m (below canopy) and the third layer: 7.4m to 40.7 m (near canopy and above). In summer, these three groups of layers were further separated with larger variations whereas such distinction became smaller in fall. The diurnal variation of $CO_2$ concentration in the first three layers near surface always showed higher concentration with larger variability. Typically, $CO_2$ concentration showed peaks in early morning and in the evening. After the evening peak, $CO_2$ concentration gradually increased except for those near the surface (i.e., 0.1, 1.0 and 4.0 m) where the concentrations actually decreased. We suspect that this could be attributed to the drainage flow of $CO_2$ along the hill slope from the headwater to downstream, which is not taken into account for net ecosystem $CO_2$ exchange. In comparison to the results of other studies, the distinct and different vertical structures of $CO_2$ concentrations observed at our site may be due to complex terrain and weak turbulent mixing under calm conditions at the site. The annual mean of diurnal variation of $CO_2$ storage flux from single level ranged from -0.6 to $0.9{\mu}mol\;m^{-2}s^{-1}$ and from multi-level from -1.2 to $1.0{\mu}\;{\mu}mol\;m^{-2}s^{-1}$. When compared against the results from the multi-level concentrations, the storage flux estimated from a single-level concentration was generally adequate except for specific hours near sunrise and sunset. Further details and their implication will be discussed in the presentation.

  • PDF

황해 대륙붕에 서식하는 중형저서동물 군집 특성 (Characteristics of Meiofauna Community Inhabiting Continental Shelf of Yellow Sea, Korea)

  • 정민규;김동성;강태욱;오제혁;신아영;오철웅
    • 한국해양학회지:바다
    • /
    • 제27권2호
    • /
    • pp.103-125
    • /
    • 2022
  • 본 연구는 황해 중부해역의 대륙붕에 서식하는 중형저서동물의 군집 특성을 파악하기 위한 연구로서, 이를 위해 2018년부터 2020년까지 북위 35도, 36도, 37도에 위치한 수심 18~90 m의 13개 정점에서 조사를 수행하였다. 2018년 10월 5개 정점, 2019년 4월 9개 정점, 2020년 8월 6개 정점에서 봄, 여름, 가을의 3계절에 조사를 진행하였으며, 중형저서동물 시료는 직경 3.6 cm의 아크릴 코어러를 이용하여 각 정점에서 반복수 3회로 채집하였다. 조사해역의 중형저서동물의 서식밀도는 45~1029 inds./10 cm2범위로 이는 기존의 황해에서 진행되었던 국내 연안과 중국 중부해역 연구와 유사한 결과를 보였다. 중형저서동물의 계절에 따른 서식밀도는 가을에 800±69 inds./10 cm2로 가장 높은 서식밀도를 보였고, 여름에 260±48 inds./10 cm2로 가장 낮았다. 중형저서동물은 총 19개의 분류군이 출현하였으며, 평균값은 9개의 분류군 수를 보였다. 출현 분류군 중 가장 우점하는 분류군은 선충류로 전체 서식밀도의 80.8%로 나타났으며, 그 다음으로 저서성 요각류(8.8%), 저서유공충류(4.7%) 순으로 나타났다. 중형저서동물의 크기 분포는 63 ㎛의 망목을 통과하고 125 ㎛크기의 체에 걸러지는 생물의 서식밀도가 가장 높았으며 1~0.5 mm가 가장 낮게 나타났다. 중형저서동물의 퇴적물 내 수직적 분포는 퇴적물 표층에서 깊이가 깊어질수록 서식밀도가 점차 감소하는 양상을 보였다. 저서환경을 파악하기 위해 중형저서동물을 활용한 N/C ratio, MPI, ITD 지수 분석결과 계절별로 차이를 보이기는 하였으나, 전반적으로 오염을 나타내는 값은 나타나지 않았다.

한국 동해 연안에 출현하는 도루묵(Arctoscopus japonicus)의 식성 (Feeding Habits of the Sandfish, Arctoscopus japonicus in the Coastal Waters of East Sea, Korea)

  • 진수연;김도균;성기창;강다연;이주은;박현솔;양혜진;서호영;백근욱
    • 한국어류학회지
    • /
    • 제34권2호
    • /
    • pp.113-118
    • /
    • 2022
  • 이번 연구에 사용된 도루묵은 2020년 1월부터 2021년 12월까지 우리나라 동해에서 동해구외끌이저인망과 연안자망 어업을 통해 총 781개체를 채집하였다. 채집된 도루묵의 전장범위는 14.8~25.4 cm였다. 도루묵의 가장 중요한 먹이생물은 54.7%의 상대중요도지수비를 나타낸 단각류였으며, 그 다음으로는 각각 33.7%와 11.6%를 차지한 두족류와 난바다곤쟁이류였다. 그외 게류, 새우류, 어류, 갯지렁이류가 출현하였으나 그 양은 매우 적었다. 계절별 위내용물 조성을 살펴본 결과, 모든 계절에 단각류를 주로 섭식하였으며, 여름철에 두족류의 섭식비율이 가장 높았으며, 봄철에 난바다곤쟁이류의 비율이 가장 높았다. 크기군별 위내용물 조성을 살펴본 결과, 도루묵은 모든 크기군에서 단각류가 가장 중요한 먹이생물이었으며, 성장함에 따라 단각류와 난바다곤쟁이류의 비율은 감소하고 두족류의 비율은 증가하는 경향이 관찰되었다. 개체당 평균먹이생물 개체수는 유의한 차이를 보이지 않은 반면, 중량은 크기군이 증가함에 따라 증가하는 경향이 관찰되었다.

안동시 저수지에서의 대량 어류 폐사에 대한 원인과 대책에 관한 연구 (Study on Causes and Countermeasures for the Mass Death of Fish in Reservoirs in Andong-si)

  • 배수호;황선진;김연정;정철호;김성윤;유건상
    • 한국환경농학회지
    • /
    • 제42권1호
    • /
    • pp.52-62
    • /
    • 2023
  • This study focused on determining the specific causes and prevention methods of mass fish deaths occurred in five reservoirs (Gagugi, Neupgokgi, Danggokgi, Sagokji, and Hangokji) in Andong-si. For this purpose, a survey of agricultural land and livestock in the upper part of the reservoirs and analysis of water quality in the reservoir irrespective of whether it rains or not were conducted. We attempted to examine the changes in dissolved oxygen (DO) in the surface and bottom layers of reservoirs and changes in DO depending on the amount of livestock compost and time. Based on the above investigations, treatment plans were established to efficiently control the inflow of contaminated water into reservoirs. The rainfall and farmland areas in the upper part of the reservoir were investigated using Google and aviation data provided by the Ministry of Land, Infrastructure, and Transport. The current status of livestock farms distributed around the reservoirs was also examined because compost from these farms can flow into the reservoir when it rains. Various water quality parameters, such as phosphate phosphorus (PO4-P) and ammonium nitrogen (NH3-N), were analyzed and compared for each reservoir during the rainy season. Changes in the DO concentration and electrical conductivity (EC) were also observed at the inlet of the reservoir during raining using an automated instrument. In addition, DO was measured until the concentration reached 0 ppm in 10 min by adding livestock compost at various concentrations (0.05%, 0.1%, 0.3%, and 0.5% by wt.), where the concentration of the livestock compost represents the relative weight of rainwater. The DO concentration in the surface layer of reservoirs was 3.7 to 5.3 ppm, which is sufficient for fish survival. However, the fish could not survive at the bottom layer with DO concentration of 0.0-2.1 ppm. When the livestock compost was 0.3%, DO required 10-19 h to reach 0 ppm. Considering these results, it was confirmed that the DO in the bottom layer of the reservoir could easily change to an anaerobic state within 24 h when the livestock compost in the rainwater exceeds 0.3%. The results show that the direct cause of fish mortality is the inflow of excessive livestock compost into reservoirs during the first rainfall in spring. All the surveyed reservoirs had relatively good topographical features for the inflow of compost generated from livestock farms. This keeps the bottom layer of the reservoir free of oxygen. Therefore, to prevent fish death due to insufficient DO in the reservoir, measures should be undertaken to limit the amount of livestock compost flowing into the reservoir within 0.3%, which has been experimentally determined. As a basic countermeasure, minerals such as limestone, dolomite, and magnesia containing calcium and magnesium should be added to the compost of livestock farms around the reservoir. These minerals have excellent pollutant removal capabilities when sprayed onto the compost. In addition, measures should be taken to prevent fish death according to the characteristics of each reservoir.

2014년 부산 연안 해역에서 계절적 환경특성에 따른 식물플랑크톤 군집의 변화양상 (Seasonal changes in phytoplankton community related with environmental factors in the Busan coastal region in 2014)

  • 윤지남;임영균;김동선;김영옥;백승호
    • 환경생물
    • /
    • 제40권1호
    • /
    • pp.112-123
    • /
    • 2022
  • 본 연구는 2014년 동계, 춘계, 하계, 추계 부산 연안 해역에서 식물플랑크톤 군집구조와 그들의 성장에 미치는 환경요인을 파악하기 위해 25개의 정점에서 생물학적 요인과 무생물학적 요인을 조사하였다. 부산 연안 해역에서 식물플랑크톤의 현존량 및 군집조성은 강우에 의한 낙동강 방류수에 크게 의존되는 특성과 더불어, 염분 분포가 생물의 집적에 중요하게 작용하는 것으로 파악됐다. 염분은 영양염 DIN (R2=0.72, p<0.001) 및 DSi (R2=0.78, p<0.001)와 유의한 상관관계를 확인하였으나, DIP (R2=0.037, p>0.05)는 염분과 유의한 관계성은 없었다. 이는 2014년 하계 강우에 의한 연안역으로 담수의 유입은 질소와 규소기원의 영양염 공급을 초래하였고, 식물플랑크톤 중 규조류와 은편모조류의 증식에 중요하게 작용하였다. 계절적으로 식물플랑크톤의 현존량은 하계, 추계, 춘계, 동계 순으로 높게 나타났다. Chl. a 농도에 대한 기여율은 식물플랑크톤의 총 현존량과 높은 양의 상관관계(R2=0.84, p<0.001)를 보였고, 그중에서도 은편모조류(R2=0.76, p<0.001) 및 규조류(R2=0.50, p<0.001)의 기여율이 상대적으로 높게 나타난 것을 파악하였다. 결과적으로 부산 연안 해역은 낙동강 하구와 부산 도심 및 항만기원의 유기물 부하로, 식물플랑크톤의 증식이 빠르게 일어날 수 있는 환경변화를 파악하였다. 특히, 내측과 외측은 영양염 농도뿐만 아니라, 식물플랑크톤의 군집구조 및 현존량의 차이도 크게 나타났고, 이는 계절적으로 상이한 특성을 보였다.

양액의 NO3- 비율이 수경재배 참외의 생육과 수량에 미치는 영향 (Evaluation of Cultivation Characteristics according to NO3- Ratio of Nutrient Solution for Korean Melon in Hydroponic Culture)

  • 원도연;최지혜;백창현;박나윤;강민구;서영진
    • 생물환경조절학회지
    • /
    • 제32권3호
    • /
    • pp.249-255
    • /
    • 2023
  • 참외는 동북아시아 지역에서 대부분 재배되고 있고, 한국에서 주로 생산되는 과일로서 단위면적당 수확량은 지속적으로 향상되고 있지만 재배방식은 토경재배에 국한되어 있기 때문에 규모화, 생력화를 위한 수경재배 기술 개발이 필요하다. 본 연구에서는 보온부직포를 이용한 수경재배로 참외를 재배할때 영양생장기 배양액 내 질산태질소 비율에 따른 참외 생육의 변화를 확인했다. 배양액에서 질산태질소 비율이 증가할수록 초장은 길어지고, 엽장, 엽폭, 절간장도 함께 증가하였다. 생육 30일차의 SPAD값은 질산태질소 비율이 증가할수록 감소하였다. 질산태질소 비율에 낮을수록 암꽃 개화가 빨리 되었고, 과실 성숙에서는 처리 간 차이가 없었다. 질산태질소 비율에 따른 과실의 형태는 차이가 없었고, 경도는 질산태질소의 비율이 낮을수록 높아 과실이 단단하였다. 3월에서 7월까지 총 수확량은 KM3 5,650kg/10a, KM1 4,439kg/10a로 KM3가 27% 높았고 특히, 참외 가격이 높은 3월에서 5월까지 수량은 KM3가 KM1보다 36% 높았다. 따라서 12월 정식되어 봄철부터 생산되는 참외의 수경재배에 적합한 질산태질소는 6.5-10me·L-1 수준으로 공급하는 것이 적당할 것으로 판단되었다.

낙동강 수계 중 1,4-dioxane의 모니터링 및 위해성 평가 (Monitoring and risk assessment of 1,4-Dioxane in Nakdong river)

  • 이지영;김정화;김현구;최종호;김승기;표희수
    • 분석과학
    • /
    • 제21권5호
    • /
    • pp.383-391
    • /
    • 2008
  • 1,4-Dioxane은 IARC (International Agency for Research on Cancer)에서 발암가능그룹으로 분류하고 있으며, WHO (World Health Organization)는 1,4-dioxane의 권고기준농도를 50 ng/mL로 설정하고 있다. 이러한 1,4-Dioxane의 독성과 음용수의 섭취량을 고려할 때, 음용수 섭취로 인한 인체 유해영향이 우려되고 있으며, 따라서 1,4-dioxane의 검출이 빈번한 낙동강 수계의 정수 및 원수의 모니터링은 중요성을 갖는다. 낙동강 수계 정수장 시료 중 1,4-dioxane 농도를 2000년부터 2007년까지 모니터링 한 결과 정수는 0.24~240.20 ng/mL의 농도 범위로 22.68 ng/mL의 평균값을 나타내었으며, 원수는 0.39~81.90 ng/mL의 농도범위로 19.15 ng/mL의 평균값을 나타내었다. 또한 2004년 수질감시항목 지정 이후 1,4-dioxane의 평균검출 농도는 저감되는 경향을 보였으나, 검출빈도는 변화가 없었다. 수질감시항목으로 지정된 2004년 이전과 이후의 위해도 평가 결과 낙동강 수계에서의 95 percentile 초과발암위해도 값이 2004년 이전의 정수는 $6.63{\times}10^{-6}$, 원수는 $3.17{\times}10^{-6}$로 나타났으며, 2004년 이후의 정수는 $2.10{\times}10^{-6}$, 원수는 $1.22{\times}10^{-6}$로 나타나 2004년 이후 초과발암위해도가 감소되는 경향을 보였다. 또한 계절별로 비교했을 때 봄 겨울에 주로 많이 검출되었다.

알레르기 비염에 관한 임상적 연구 (A clinical study of allergic rhinitis)

  • 채병윤
    • 대한한의학회지
    • /
    • 제21권3호
    • /
    • pp.149-165
    • /
    • 2000
  • As recent developments of Immunology and Nuclear medicine, serum IgE and IgG values are helpful in the diagnosis and evaluation of the therapeutic effects of nasal allergies. But in Korea, air pollution and the increased use of food additives have become leading factors in nasal allergies, It seems to be induced by environmental change, especially industrialization and urbanization, so allergic rhinitis in our environment has changed in accordance with the changes made in the living environment. Therefore this study is attempted in order to observe a clinical analysis which places more importance on allergic rhinitis. We studied 200 patients who had visited Kyunghee Oriental Medical Center with allergic rhinitis from January 1, 1999 to December 31, 1999 The results were as follows: 1. The sex distribution was 114 males(57%) and 86 females(43%). In age distribution, the average age was 25. In males, ages ranged from 3 to 66 years old and the average was 23.81. In females, ages ranged from 4 to 67 years old and the average was 28.57. The peak age was 30~39 years old(24%); under 9 years old and 10~19 years old were each 18%; 20~29 years old was 22%; 40~49 years old was 11 %; over 50 years old 6.5%. The gulf between males and females showed a statistically significant difference(P<0.025). 2. In the age of onset, male' s maximum was 62.5, minimum was 0.25; female s maximum was 59.5, minimum was 0.2. Under 9 years old was the most with 34%(male 24%, female 10%), 10~19 years old was 18%, 20~29 years old was 22.5%, 30~39 years old was 13.50%, over 40 years old was 12%, The gulf between males and females were showed statistically significant difference.(p<0.014) 3. The average duration of the disease was 5.67 years. In male and female, the maximum was 30, the minimum was 0.05; under 5 years old was the most with 62%(male 34.50%, female 27.50%); 6~10 years old was 23%. So, under 10 years old was 85%. There was no statistically significant difference in the duration of disease. 4. Regarding type of residence, 47.50% of patients with allergic rhinitis lived in apartments, 52.50% lived in houses. In males, 29.50% lived in apartments, 27.50% lived in houses. In females, 18% lived in apartments, 25% lived in houses. There was no statistically significant difference in the residence by T-test and chi-test. 5. In the distribution of season, spring is the most with 29.5% of patients, winter 28%, fall 25.5%, and summer 17%. But there was no statistically significant difference. 6. After observing 200 patients with allergic rhinitis, classifying main symptoms into 5 types, sneezing was the main symptom in 177cases(88.50%), nasal obstruction in 176cases(88%), rhinorrhea in 169cases(84.5%), post nasal discharge in 87cases(43.50%), and itching in I04cases(52%). The Cumulus ration is 98.50% and symptoms overlapped with an average 3.57±0.1 times but in an analysis of variance of these symptoms, the gulf between males and females was not recognized as statistically significant by T-test and ANOVA. 7. Patients whose families have allergic diseases account for 90 cases(45%) : 49cases(24.50%) male and 41cases(20.50%) female. There were 4 cases (71.11 %) whose families have allergic rhinitis, 9cases(10%) of asthma, and 7.78% with allergic dermatitis. There were 61 (67.80%) cases of patients whose parents have allergic diseases; cases wherein the patient s child had allergic diseases numbered 13 (14.45%); and cases with a sibling with allergic diseases totalled 16cases (17.80%). There was no statistically significant difference in allergic disease regarding sex, parents, or siblings by chi-test. 8. Blood type: For males, type A is the most common, with 37cases(18.5%), followed by type B with 32cases(16%), type O 28cases(l4%) and type AB 13cases(6.5%). For females, type B is the most common, with 30cases(15%), followed by type O with 23cases(l1.5%), type A with 18cases(9%) and type AB with 13cases(6.5%). There was no statistically significant difference in blood type by chi-test. 9. In the selection of prefered food, most patients prefer cool food, with 98 such cases(49%), tepid food in 54cases(27%) and warm food in 48cases(24%). These showed a statistically significant difference in the selection of prefered food between males and females by chi-test(p<0.009). 10. The state of Past History was classified into II types. chronic hypertrophic rhinitis is the most common with 11cases (18.64%), tonsil and adenoid hypertrophy is 8cases(l3.56%), sinusitis is 6cases(10.17%), nasal septum deviation is 4cases, nasal polyp is 2cases, others are 10cases(l6.95%). No statistically significant difference in past history between males and females was shown, but a statistically significant difference was shown when males and females were compared with total cases by T-test(p<0.002, P<0.0008). 11. Regarding complications, 37 patients (28.91%) had sinusitis: 22cases(17.19%) in male, 15cases(11.72%) in female. Chronic hypertrophic rhinitis was found in 15cases(11.72%). Others are under 10%. There was no statistically significant difference in the type of complications between males and females, but a statistically significant difference was shown when males and females were compared with total cases by T-test(P<0.00l, P<0.007). 12. In the treatment, medication was used 1691 times, an average of 2.58 times. No.34 was used 370 times for 124 cases, an average of 2.98 times. No. 152 was used 318 times for 106 cases, an average of 3.00 times. No.151 was used 307 times for 97cases, an average of 3.16 times. No. 31 was used 117 times for 33 cases, an average of 3.55 times. No 25 was used 116 times for 33 cases, an average of 3.52 times. 13. In the duration of treatment, the most frequent is 1 week(69cases, 34.50%), the maximum is 20weeks, and the minimum is 1week. A treatment period of 2~3 weeks accounted for 32% of cases, a period of 4~5weeks accounted for 13.5%. The gulf between males and females showed a statistically significant difference in the duration of treatment.(p<0.01). There was a statistical significance when the males were compared with total cases by ANOVA(P<0.03). 14. A comparison between before-treatment and after-treatment showed a statistically significant difference in treatment by T-test (p<0.01) and F-test (p<0.0058).

  • PDF

불량환경하(不良環境下)에서의 제초제(除草劑) 약해(藥害)와 경감기술(輕減技術) (Herbicidal Phytotoxicity under Adverse Environments and Countermeasures)

  • 권용웅;황형식;강병화
    • 한국잡초학회지
    • /
    • 제13권4호
    • /
    • pp.210-233
    • /
    • 1993
  • The herbicide has become indispensable as much as nitrogen fertilizer in Korean agriculture from 1970 onwards. It is estimated that in 1991 more than 40 herbicides were registered for rice crop and treated to an area 1.41 times the rice acreage ; more than 30 herbicides were registered for field crops and treated to 89% of the crop area ; the treatment acreage of 3 non-selective foliar-applied herbicides reached 2,555 thousand hectares. During the last 25 years herbicides have benefited the Korean farmers substantially in labor, cost and time of farming. Any herbicide which causes crop injury in ordinary uses is not allowed to register in most country. Herbicides, however, can cause crop injury more or less when they are misused, abused or used under adverse environments. The herbicide use more than 100% of crop acreage means an increased probability of which herbicides are used wrong or under adverse situation. This is true as evidenced by that about 25% of farmers have experienced the herbicide caused crop injury more than once during last 10 years on authors' nationwide surveys in 1992 and 1993 ; one-half of the injury incidences were with crop yield loss greater than 10%. Crop injury caused by herbicide had not occurred to a serious extent in the 1960s when the herbicides fewer than 5 were used by farmers to the field less than 12% of total acreage. Farmers ascribed about 53% of the herbicidal injury incidences at their fields to their misuses such as overdose, careless or improper application, off-time application or wrong choice of the herbicide, etc. While 47% of the incidences were mainly due to adverse natural conditions. Such misuses can be reduced to a minimum through enhanced education/extension services for right uses and, although undesirable, increased farmers' experiences of phytotoxicity. The most difficult primary problem arises from lack of countermeasures for farmers to cope with various adverse environmental conditions. At present almost all the herbicides have"Do not use!" instructions on label to avoid crop injury under adverse environments. These "Do not use!" situations Include sandy, highly percolating, or infertile soils, cool water gushing paddy, poorly draining paddy, terraced paddy, too wet or dry soils, days of abnormally cool or high air temperature, etc. Meanwhile, the cultivated lands are under poor conditions : the average organic matter content ranges 2.5 to 2.8% in paddy soil and 2.0 to 2.6% in upland soil ; the canon exchange capacity ranges 8 to 12 m.e. ; approximately 43% of paddy and 56% of upland are of sandy to sandy gravel soil ; only 42% of paddy and 16% of upland fields are on flat land. The present situation would mean that about 40 to 50% of soil applied herbicides are used on the field where the label instructs "Do not use!". Yet no positive effort has been made for 25 years long by government or companies to develop countermeasures. It is a really sophisticated social problem. In the 1960s and 1970s a subside program to incoporate hillside red clayish soil into sandy paddy as well as campaign for increased application of compost to the field had been operating. Yet majority of the sandy soils remains sandy and the program and campaign had been stopped. With regard to this sandy soil problem the authors have developed a method of "split application of a herbicide onto sandy soil field". A model case study has been carried out with success and is introduced with key procedure in this paper. Climate is variable in its nature. Among the climatic components sudden fall or rise in temperature is hardly avoidable for a crop plant. Our spring air temperature fluctuates so much ; for example, the daily mean air temperature of Inchon city varied from 6.31 to $16.81^{\circ}C$ on April 20, early seeding time of crops, within${\times}$2Sd range of 30 year records. Seeding early in season means an increased liability to phytotoxicity, and this will be more evident in direct water-seeding of rice. About 20% of farmers depend on the cold underground-water pumped for rice irrigation. If the well is deep over 70m, the fresh water may be about $10^{\circ}C$ cold. The water should be warmed to about $20^{\circ}C$ before irrigation. This is not so practiced well by farmers. In addition to the forementioned adverse conditions there exist many other aspects to be amended. Among them the worst for liquid spray type herbicides is almost total lacking in proper knowledge of nozzle types and concern with even spray by the administrative, rural extension officers, company and farmers. Even not available in the market are the nozzles and sprayers appropriate for herbicides spray. Most people perceive all the pesticide sprayers same and concern much with the speed and easiness of spray, not with correct spray. There exist many points to be improved to minimize herbicidal phytotoxicity in Korea and many ways to achieve the goal. First of all it is suggested that 1) the present evaluation of a new herbicide at standard and double doses in registration trials is to be an evaluation for standard, double and triple doses to exploit the response slope in making decision for approval and recommendation of different dose for different situation on label, 2) the government is to recognize the facts and nature of the present problem to correct the present misperceptions and to develop an appropriate national program for improvement of soil conditions, spray equipment, extention manpower and services, 3) the researchers are to enhance researches on the countermeasures and 4) the herbicide makers/dealers are to correct their misperceptions and policy for sales, to develop database on the detailed use conditions of consumer one by one and to serve the consumers with direct counsel based on the database.

  • PDF

"삼국사기(三國史記)"에 기록된 의약내용(醫藥內容) 분석 (Study on Medical Records In ${\ulcorner}$the Historical Records of the Three Kingdoms${\lrcorner}$)

  • 신순식;최환수
    • 제3의학
    • /
    • 제2권1호
    • /
    • pp.35-54
    • /
    • 1997
  • We tried to observe the features of ancient medical practice by analysing the records related to medicine in the book, ${\ulcorner}$the Historical Records of the Three Kingdom${\lrcorner}$ of which content includes the features of medicine in mythology, plague, delivery of twins, drugs, medical system, shamanism, constitutional medicine, psychiatry, forensic medicine, deformity, a spa, medical phrase, health and welfare work, religion, death. physiological anatomy, Taoist medicine, acupuncture, the occult af of transformation and etc. Our initial concern was about where to draw line as of medical field and we defined medicine in more broad meaning. The book ${\ulcorner}$the Historical Records of the Three Kingdoms${\lrcorner}$ describes the world of mythology by way of medicine which is not clearly a conventional one. There appears records of birth of multiple offsprings 7 times in which cases are of triplets or more. Delivering multiple offsprings were rare phenomenon though such fertility was highly admired. This shows one aspect of ancient country having more population meant more power of the nation. Of those medical records conveyed in that book includes stories of childbirth such as giving birth to a son after praying, giving birth to Kim Yoo-shin after 20 months after mother's dream of conception, and a song longing for getting a laudable child. Plagues were prevalent throughout winter to spring season and one can observe various symptoms of plagues in the record. Of these epidemic diseases, cold type might have been more common than the heat one. Appearance of epidemic diseases frequently coincided with that of natural disasters that this suggests a linkage between plague and underlying doctrine on five elements' motion and six kinds of natural factors. There exists only a few names of diseases such as epidemic disease, wind disease, and syndrome characterized by dyspnea. Otherwise there appeared only afflictions that were not specified therefore it remains cluless to keep track of certain diseases of prevalence. Since this ${\ulcorner}$Historical Records of the Three Kingdoms'${\lrcorner}$ wasn't any sort of medical book, words and terms used were not technical kind and most were the ones used generally among lay people. Therefore any mechanisms of the diseases were hardly mentioned. Some of medicinal substances such as Calculus Bovis, Radix Ginseng, Gaboderma Luciderm, magnetitum were also in use in those days. 53 kinds of dietary supplies appears in the records and some of these might have been used as medicinal purpose. Records concerning dicipline of one's body includes activities such as hunting, archery, horseback riding etc. In Shilla dynasty there were positions such as professor of medicine, Naekongbong(內供奉), Kongbong's doctor(供奉醫師), Kongbong's diviner(供奉卜師). As an educational facility, medical school was built at the first year of King Hyoso's reign and it's curricula included various subjects as ${\ulcorner}$Shin Nong's Herbal classic${\lrcorner}$, ${\ulcorner}$Kabeul classic of acupuncture and moxbustion${\lrcorner}$, ${\ulcorner}$The Plain Questions of the Yellow Emperor's Classic of Internal Medicine${\lrcorner}$, ${\ulcorner}$Classic of Acupuncturer${\lrcorner}$, ${\ulcorner}$The Pulse Classic${\lrcorner}$, ${\ulcorner}$Classic of Channels and Acupuncture Points${\lrcorner}$ and ${\ulcorner}$Difficult Classic${\lrcorner}$. There were 2 medical professors who were in charge of education. To establish pharmacopoeia, 2 Shaji(舍知), 6 Sha(史), 2 Jongshaji(從舍知) were appointed. In Baekje dynasty, Department of Herb was maintained. Doing praying for the sake of health, doing phrenology also can be extended to medical arena. Those who survived over 100 years of age appear 3 times in the record, while 98 appears once. The earliest psychiatrist Nokjin differentiated symptoms to apply either therapies using acupuncture and drug or psychotherapy. There appears a case of rape, a case of burying alive with the dead, 8 cases of suicide that can characterize a prototype of forensic medicine. Deformity-related records include phrases as follow: 'there seems protrudent bone behind the head', 'a body which has two heads, two trunks, four arms.', 'a body equipped with two heads' In those times spa can be said to be used as a place for he리ing, convalescence, and relaxation seeing the records describing a person pretended illness and went to spa to enjoy with his friends. Priest doctors and millitary surgeons were in charge of the medical sevice in the period of the Three Kingdoms by the record written by Mookhoja(墨胡子) and Hoonkyeom(訓謙). Poor diet and regimen makes people more vulnerable to diseases. So there existed charity services for those poor people who couldn't live with one's own capacity such as single parents, orphans, the aged people no one to take care and those who are ill. The cause of affliction was frequently coined with human relation. There appeared the phenomenon of releasing prisoners and allowing people to become priests at the time of king's suffering. Besides, as a healing procedure, sutra-chanting was peformed. There appears 10 cases of death related records which varies from death by drowning, or by freezing, death from animals, death from war, death from wightloss and killing oneself at the moment of spouse's death and etc. There also exist certain records which suggest the knowledge of physiology and anatomy in those times. Since the taoist books such as ${\ulcorner}$Book of the Way and Its Power(老子道德經)${\lrcorner}$ were introduced in the period of Three Kingdoms, it can be considered that medicine was also influenced by taoism. Records of higher level of acupuncture, records which links the medicine and occult art of transformation existed. Although limited, we could figure out the medical state of ancient society.

  • PDF