차밭에 설치된 차광망의 동해경감 효과

황정규 ( Jung Gyu Hwang ),김용덕 ( Yong Duck Kim ) 한국농림기상학회 2014 한국농림기상학회지 Vol.16 No.2

In the result of effect on freezing damage reduction by the shade net colors and the shade rate to tea trees during wintering period, the high shade ratio decreased tea trees growth and increased freezing damage and 55% of shade ratio based on non treatment developed new leafs and green leaf productivity. By the shade net colors, colorless shade net (55% of shade type) treatment and green shade net treatment increased green leaf productivity and decreased damaged area compare to non treatment shade net and black shade net treatment. Colorless net shade treatment reduced over 50% of freezing damage and increased (10a) 68 kg for green leaf productivity compare to non treatment shade net. The colors of shade net treatments for reduction freezing damaged in order of Black < Green < Colorless but reduction of freezing damage was so high. In the relative microclimates, treatment shade nets were 0.7oC lower, average relatively humidity 14.9% higher, soil temperature 0.6oC lower and soil moisture 4.6% higher than non treatment shade net. And treatment shade nets decreased average wind speed 0.7 m/s and it showed us treatment net shades effected to excessive evapotranspiration and soil dry by wind and considered one of good solution for freezing damages.

단보 : 하동녹차 재배지역의 기상요소별 분석

황정규 ( Jung Gyu Hwang ),김종철 ( Jong Cheol Kim ),조경환 ( Kyoung Hwan Cho ),한재윤 ( Jae Yoon Han ),김루미 ( Ru Mi Kim ),김연수 ( Yeon Su Kim ),정강원 ( Gang Won Cheong ),김용덕 ( Yong Duck Kim ) 한국농림기상학회 2010 한국농림기상학회지 Vol.12 No.2

우리나라에서 대표적 녹차재배 지역인 화개지역과 악양지역의 2009년 기상특성을 정리하면 화개지역과 악양지역의 연평균 기온은 각각 14.5℃와 14.2℃이며, 두 지역의 월평균기온을 보면 가장 더운 달은 8월로 각각 25.4℃와 24.9℃이고 가장 추운 달은 1월로 각각 0.3℃와 0.2℃ 이었으며, 일 최고기온은 각각 28.4℃와 27.9℃이고 일 최저기온은 -5.0℃와 -5.4℃이다. 연평균일교차는 화개지역이 11.3℃이고 악양지역은 11.1℃이다. 화개와 악양지역의 연평균습도는 각각 62.7%와 65.3% 이고, 연강수량은 1,387mm와 1,793mm로 2008년 대비 각각 605mm와 835mm가 더 내렸고, 5월부터 8월까지 화개 1,074mm, 악양 1,374mm로 집중적인 강수량을 보였다. 이것은 2009년 전체 강수량의77.6%와 76.6%에 해당하는 수치로써 나머지 달에 비해 많은 강수량을 보임을 알 수 있다. 연평균 일조시간은 2,054.3시간으로 관측되었고 4, 5월에 각각232.2시간과 235.1시간으로 가장 긴 일조시간을 보인 반면에 7, 8월에는 각각 102.5시간과 128.8시간으로 가장 짧은 일조시간을 보였다. 풍향은 가을과 겨울에서 북서, 서, 북서계열의 서풍이 불었고 봄, 여름철에는 남동, 북북동, 남동계열의 동풍이 불었으며, 연평균 풍속은 1.5m/s로 관측 되었으며 12월이 2.0m/s로 평균 풍속이 가장 높은 달이었고 2월이 1.1m/s로 평균풍속이 가장 낮은 달이었다. 순간최대풍속은 3월 13일에 측정된 23.3m/s이었다. 2009년 조사된 기상관측정보를 토대로 매년 기상관측정보를 데이터화해서 녹차재배지역의 기상환경을 이해하고 생장환경 정보를 수집하며 최적의 녹차재배 환경의 기초자료로 활용할 수 있을 것으로 기대한다. Characteristics of meteorological elements were analyzed at Hwagae and Agyang where are the representative areas of Hadong green tea cultivation in Korea. An automatic weather monitoring system (AWS) and a simple data log were employed to measure meteorological data such as temperature, relative humidity, precipitation, and wind direction and speed for 2009. The annual average air temperature of Hwagae and Agyang was 14.5 and 14.2, respectively, showing the warmest month in August (25.4℃ for Hwagae and 24.9℃ for Agyang) and the coldest month in January (0.3℃ for Hwagae and 0.2℃ for Agyang). Annual average of daily temperature difference (= daily maximum temperature-daily minimum temperature) was 11.3℃ for Hwagae and 11.1℃ for Agyang. Hwagae and Agyang had 62.7% and 65.3% of the annual average relative humidity, respectively. Annual precipitation was 1387 mm for Hwagae and 1793 mm for Agyang of which were higher of 605mm for Hwagae and 835 mm for Agyang compared to that in 2008. Majority of precipitation ℃curred between May and August, attributing 77.6% for Hwagae and 76.6% for Agyang to the annual precipitation. The annual total sunshine duration was 2054.3 hrs in Hwagae with the longest monthly sunshine duration in May (235.1 hrs) and the shortest monthly sunshine duration in July (102.5 hrs). Dominant wind direction changed seasonally from northwesterly wind in fall and winter to southeasterly wind in spring and summer. The annual average wind speed was 1.5 m s?1 with the highest monthly wind speed of 2.0 m s?1 in December and the lowest monthly wind speed of 1.1 m s?1 in February. It is expected that continuous observation and assessment of meteorological data will improve our understanding of optimal environmental conditions for green tea cultivation and be used for developing models of green tea cultivation in the Hadong area.

로울러 다짐에 의한 콘크리트 댐 施工에 관한 實驗的 硏究

黃正奎(Hwang Jung Gyu) 대한토목학회 1981 대한토목학회지 Vol.29 No.1

重力式 댐 材料로서의 매우 된 반죽의 貧配合 콘크리트에 관한 實驗的 硏究

黃正奎(Hwang Jung Gyu) 대한토목학회 1980 대한토목학회지 Vol.28 No.6

차광재배에 의한 찻잎 성분 및 말차 품질 변화

황정규(Jung gyu Hwang),심두보(Doobo Shim),임현정(Hyeon Jeong Im),박상기(Sang Ki Park),강은주(Eun-Ju Kang),조경환(Kyung hwan Cho),배성경(Seong Kyeong Bea),이지현(Ji-hyun Lee),김종철(Jong Cheol Kim) 한국차학회 2018 한국차학회지 Vol.24 No.2

Morphologic and physicochemical changes of shading cultivated tea (Camellia sinensis) tree leaves were investigated during 26 days with 95% shading treatment. Shading cultivation showed higher leaf area (10%) and moisture content (12%) than non-shading cultivation. The shading cultivation increased the total free amino acid (3.4-fold), theanine (3.7-fold), arginine (10.8-fold) and caffeine levels (2.0-fold) but decreased the total catechin contents, EGCG (epigallocatechin gallate) and EGC (epigallocatechin) levels of tea leaves. The SPAD value and total chlorophyll contents of the shading cultivation were increased by 1.1- and 2.1-fold, respectively. The results of a color analysis showed that lightness (L*) of non-shaded was higher than that of shading cultivated matcha. However, the greenness (a*) and yellowness (b*) of shading cultivated matcha were higher than those of non-shading cultivation. The surface color of shading cultivated matcha had higher chroma- and G-values than non-shading cultivated matcha, which represents real green color. Thus, the shading cultivation is suitable to prepare a high-quality matcha product.

2011년 남부지방 차나무 저온 피해 조사

황정규 ( Jung Gyu Hwang ),김용덕 ( Yong Duck Kim ) 한국농림기상학회 2012 한국농림기상학회지 Vol.14 No.4

Despite frequent freezing injury to tea trees due low temperature, drought, and strong wind during wintertime, no comprehensive measurements have been taken. We selected and examined 9 locations in Hwagae-myeon and 4 places in Agyang-myeon, Hadong-gun, Gyeonsanggnam-do where low temperature damage had occurred between December 2010 and February 2011. Our objective is to examine the effect of frost damage on the morphological symptom and harvest of a tea tree exposed to a constant low temperature environment during wintertime. The results of our analyses on meteorological environment, tea leaf chromaticity, water content and trypan blue are as follows: (1) the number of days with temperature of -10oC or less, which were subject to frost damage to a tea tree were 8 and 13.6% during the winterization period in 2011; (2) the accumulated time was 1,308 minutes, and the longest duration at -10oC was 588 minutes from 21:08 p.m. 15 January to 7:30 a.m. 16th January. The rainfall was only 104 mm which was 306 mm less than the previous year; (3) the lightness L values in 2011 were higher than in 2012 due to dehydration and necrosis by blue discoloration and red discoloration at all areas in chromaticity measurement; (4) the water content in a tea leaf in 2011 was higher than in 2012 due to low rainfall and strong wind, and almost no cell death phenomenon was observed from normal tea leaves subject to no low temperature stress in a trypan blue analysis; and (5) partial coloration due to cell death, however, took place in the leaves damaged by blue discoloration subject to low temperature stress, and most coloration due to cell death took place in the leaves damaged by red discoloration.

공간적·비공간적 도시구조 변화에 따른 창조산업 인구 연구

안정근,황정규,Ahn, Jung Geun,Hwang, Jeong Gyu 대한토목학회 2013 대한토목학회논문집 Vol.33 No.6

국내 많은 도시들은 경제 성장률 하락에 따른 고용창출 하락, 출산률 감소에 따른 인구감소, 노령인구 증가에 따른 도시활력 감소, 도심 공동화에 따른 도시기능 쇠퇴 등 20세기에 겪어보지 못한 새로운 도시양상에 직면하고 있다. 이에 따라 이들 도시들은 도시의 당면한 문제를 해결하고 도시 경쟁력을 향상 시킬 수 있는 다양한 방안 중 하나로 창조도시에 대한 관심이 높아지고 있다. 창조도시는 주민들이 다양한 문화생활과 여가활동이 가능하고 혁신적인 산업을 진흥할 수 있는 장소가 풍부한 도시로서 과학자, 기술자, 건축가, 디자이너, 작가, 예술가, 음악가 등의 창조산업 인구에 의해 선도된다. 따라서 본 연구는 국내 도시를 인구규모별로 구분하여 어떠한 도시구조가 창조산업 인구와 관계가 있는지를 제시하는데 목적이 있다. 연구결과 광역시에서는 문화행사 수가 창조산업 인구와 관계가 있으며 대도시에서도 문화행사 수와 문화공간 수가 창조산업 인구에 영향을 미치는 것으로 나타났다. 한편 중소도시에서는 문화행사 수와 환경오염 관리시설이 창조산업 인구 유인에 영향을 미치는 것으로 나타났다. 따라서 창조산업 인구 유입에 가장 큰 영향을 미치는 요소가 도시문화임에 따라 도시 경쟁력을 강화하기 위해서는 다양한 도시문화 환경을 조성하는 것이 시급하다. A number of cities have been constantly decreasing their residents by the low quality of life and environment. A creative industry is being noticed for not only securing the competitiveness of the city but also increasing the number of population. Thus, the urban structure for inducing creative industry population becomes to major issue to the most of local governments. This study aims to suggest the relationships between urban structure and creative industry population based on different urban sizes. To measure the population of creative industry, this study used the 'National Business Survey' by the National Statistical Office, which classified the statistical data of industrial places on a basis of city, district, and borough. Based on the results of expert questionnaire surveys, it conducted an analysis on the importance of urban structure and drew some critical factors that have an important effect on attracting the population of creative industry. The relationships between creative industry population and urban structure evaluated by multiple regression analysis. This study found out that the cultural factors like cultural space or culture events were drawn as very significant factors that have a positive effect on the population of creative industry population. It is judged that the creation of culture environment, which can enrich the creative industry, is needed to strengthen the competitiveness of the cities.

풋거름작물에 따른 차나무의 생육 및 잡초발생 비교

심두보(Doobo Shim),황정규(Jung Gyu Hwang),권미진(Mi Jin Kwon),전승호(Seung ho Jeon) 한국차학회 2020 한국차학회지 Vol.26 No.2

본 연구는 친환경 차나무 재배에서 월동 풋거름작물 재배시 차나무의 생육특성 및 잡초발생에 미치는 영향을 알아보고, 차나무 관리에 유용한 초종을 선발하기 위한 기초적 자료를 얻기 위하여 수행하였다. 무처리의경우 13종의 잡초 229주, 생체중 4,344 g (건물중 745 g)이 조사되었으며, 크림슨클로버 처리에서 가장 적은 3.7 종의 잡초 14.7주, 생체중 18.0 g (건물중 1.1 g) 조사되었으며, 모든 풋거름작물 처리구에서 98% 이상 잡초방제효과가 있었다. 토양유기물 함량은 무처리 14.1 g/kg으로 가장 낮았으며, 크림슨클로버 처리에서 가장 많은 2.2 배 증가한 30.5 g/kg 함량을 보였다. 차나무 생엽의 엽록소함량은 무처리 38.1, 들묵새 처리 38.3, 자운영 처리40.1, 크림슨클로버 처리 41.9로 조사되었으며, 엽록소형광에서도 크림슨클로버 처리 0.804 Fv/Fm로 가장 높았다. 잡초억제, 토양개선효과, 차나무 생육 등을 고려하였을 때, 차나무의 풋거름작물로 크림슨클로버가 가장 적합한 것으로 사료된다. This study examined the effects of green manure on the growth characteristics and weed control for tea trees in organic tea cultivation. The weed control, soil chemistry, SPAD value, and chlorophyll fluorescence were examined with five different treatments [Festuca myuros (FES), Astragalus sinicus (AST), Trifolium incarnatum (TRI), mixing sowing (Astragalus sinicus 1 + Trifolium incarnatum 2) and control]. The weed occurrence was 229 weeds of 13 flora (fresh weight 4,344 g, dry weight 745 g) in control; TRI treatment was the lowest, 14.7 weeds of 3.7 flora (fresh weight 18.0 g, dry weight 1.1 g). The mulching treatment groups showed a weed inhibition effect compared to the control (over 98%). Organic matter was lowest at 14.1 g/kg, but highest at 30.5 g/kg (2.2 times) in the TRI treatment. SPAD value and chlorophyll fluorescence of tea leaves were also highest in the TRI treatment (38.1, 41.9 Fv/Fm). Therefore, Trifolium incarnatum is considered the most effective when considering weed control, soil chemical properties, growth of tea trees, and convenience of work.

과산화수소 처리가 수수의 발아 및 초기 생장에 미치는 효과

심두보,송기은,박찬영,전승호,황정규,강은주,김종철,심상인,Shim, Doobo,Song, Ki Eun,Park, Chan Young,Jeon, Seung Ho,Hwang, Jung Gyu,Kang, Eun-ju,Kim, Jong Cheol,Shim, Sangin 한국작물학회 2018 한국작물학회지 Vol.63 No.2

As the global warming causing desertification increase, there is growing concern about damage of crops. It was to investigate how the treatment with hydrogen peroxide before leaf development affects the growth and yield of sorghum for minimizing a damage of crops to drought. The germination experiment was conducted at alternating temperature of $25^{\circ}C/20^{\circ}C$(12 hr/12 hr) under water stress condition of 0 ~ -0.20 MPa adjusted with PEG solution containing 0 and 10 mM $H_2O_2$. In order to know the effect of foliar application of hydrogen peroxide on the growth of sorghum, 10 mM hydrogen peroxide was treated to leaves at 3-leaf stage of sorghum growing in greenhouse conditions. Seed germination rate was increased by 20% in hydrogen peroxide treatment as compared to the Control. under water stress conditions (-0.15 ~ -0.20 MPa). The length of seedlings was also on the rise by the hydrogen peroxide treatment. In the greenhouse pot experiment, the morphological characteristics (plant height, stem diameter, leaf length, and leaf number) and physiological characteristics (chlorophyll content, chlorophyll fluorescence (Fv/Fm), stomatal conductance) were higher in the plants treated with hydrogen peroxide under the drought stress condition than those of plants of $H_2O$ treatment. Experiment conducted with the soil moisture gradient system showed that the foliar application of hydrogen peroxide increased photosynthetic ability of sorghum plant with respect to SPAD value and stomatal conductance and rooting capacity (root weight and root length) under drought condition. Generally, hydrogen peroxide treatment in sorghum increased the tolerance to drought stress and maintained better growth due to ameliorating oxidative stress.

저온지속시간이 차나무의 생육과 생리활성에 미치는 영향

심두보(Doobo Shim),권미진(Mi Jin Kwon),황정규(Jung Gyu Hwang),강은주(Eun-Ju Kang),송성화(Seong-Hwa Song),손용휘(Yong-Hwi Son),김종철(Jong Cheol Kim),조경환(Kyung Hwan Cho),임현정(Hyeon Jeong Im),심상인(Sangin Shim),전승호(Seung Ho Je 한국차학회 2020 한국차학회지 Vol.26 No.3

이상기후에 따른 차나무의 저온피해가 증가하고 고급 차 수확시기에 서리 등의 냉상해 증가 등으로 농가소득 감소의 원인이 되고 있다. 본 연구는 저온처리 시간에 따른 스트레스 정도를 진단하고 저온피해를 지수화하는 방법을 제시하고자 하였다. 참녹의 동일한 품종을 대상으로 영하 10℃에서 0, 1, 3, 6, 9, 12, 24, 72시간처리하고 다시 4℃ 순화처리, 10℃ 회복처리를 통한 차나무의 광합성능력, 성분 및 항산화활성을 조사하였다. 저온처리 전 차나무의 경우 0.7 이상의 Fv/Fm값(최대 양자수득율)을 보였으며, -10℃에서 1시간 처리 시, 0.530 에서 72시간 처리했을 때 0.147로 처리시간이 길어질수록 Fv/Fm값이 감소하는 경향을 보였다. 열로 인한 에너지 소실(DIo/RC)는 반응 중심비(ABS/RC)에서 흡수한 광자의 고정효율(ETo/RC)을 뺀 값으로 ABS/RC와DIo/RC는 정의상관을 보인다. 저온처리 시간이 길어질수록 ABS/RC와 DIo/RC 값은 증가하였다. 회복 후 찻잎과 지상부(줄기)의 수분함량은 무처리에서 찻잎 57.9%, 줄기 32.9%, 평균(찻잎과 줄기 수분함량) 45.4%로 6시간 이상 저온에 처리 했을때 평균 수분함량이 30.0% 미만으로 감소하였으며, 줄기의 수분함량은 12시간 이상저온처리 시 20% 미만으로 감소하고, 찻잎의 수분함량은 24시간 이상 저온처리 시 30% 미만으로 감소하였다. 카테킨 함량은 무처리 2.4%에서 저온처리 1시간 후 5.1%로 증가하였으며 이후 감소하였다. 9시간 이상 저온처리하였을 때 무처리 보다 낮은 카테킨 함량을 보였다. 카페인 함량은 저온처리 3시간에서 가장 높이 증가하였다가 이후 감소하는 경향을 보였다. 전체적으로 저온(-10℃)에서 9시간 이후 처리 했을 때 찻잎의 회복이 불가능한 것으로 사려된다. The low temperature damage of tea trees due to the abnormal climate and the increase in cold weather such as frost at the time of harvesting high-quality tea are decreasing farm household income. The purpose of this study was to suggest a method for diagnosing the degree of stress according to the time of low-temperature exposure and indexing the low-temperature damage. The varieties of tea tree (Chamnok) were exposed to 0, 1, 3, 6, 9, 12, 24, and 72 hours at -10°C, followed by a 4°C acclimation stage and a 10°C recovery stage. The photosynthetic ability, catechin·caffeine contents and antioxidant activity of the tea trees were investigated at each stage. Fv/Fm of tea leaves before cold treatment was 0.7 or higher, 0.530 for 1-hour exposure, and 0.147 for 72-hour exposure. As the exposure time increased, the Fv/Fm value tended to decrease. The energy dissipation due to heat (DIo/RC) is the value obtained by subtracting the fixed efficiency (ETo/RC) of photons absorbed from the reaction center ratio (ABS/RC). ABS/RC and DIo/RC showed a positive correlation. The ABS/RC and DIo/RC values increased with increasing exposure time. When exposed to low temperatures for more than 6 hours, the average moisture content decreased to less than 30.0%. Catechin content increased to 5.1% after 1 hour of low temperature exposure and decreased from 3 hours of exposure. When exposed to low temperature for more than 9 hours, it showed a lower catechin content than no treatment. Caffeine content peaked at 3 hours of low temperature exposure and then decreased. In conclusion, it is considered that recovery of tea leaves is impossible when exposed after 9 hours at low temperature (-10℃).