• Title/Summary/Keyword: Rice aging

Search Result 108, Processing Time 0.022 seconds

Assessment and Enhancement of Ecosystem Services of Saemangeum Area (새만금 지역의 생태계서비스 평가와 증진 방안)

  • Seung-Joon Lee;Ji-Won Choi;Choong-Hyeon, Oh
    • Korean Journal of Environment and Ecology
    • /
    • v.36 no.6
    • /
    • pp.684-692
    • /
    • 2022
  • This study was conducted to assess ecosystem services provided for Saemangeum agricultural and life sites and surrounding areas and establish measures to enhance them. The ecosystem services in the Saemangeum region were found to be different depending on its land use type. Before reclamation, the quality of ecosystem service in the Saemangeum region was high in all aspects: supply, control, culture, and support service functions. After the reclamation, however, the quality of supply, regulating, and support services declined. Therefore, it is necessary to enhance the quality of regulating and support services provided by semi-natural habitats such as rice paddy and reservoirs to improve the ecosystem service of the Saemangeum agricultural and life site. The suggested service improvement includes transforming natural ecosystems, such as forests and rural areas, and vast agricultural land into rural tourism and ecotourism and strengthening cultural service functions centered on education and research related to agriculture. To this end, it is necessary to utilize large agricultural land and agricultural infrastructure to promote agricultural production and rural tourism and government support for areas where the aging population is a problem.

Feeding rate and growth rate of earthworm(Oligochaeta : Eisenia fetida) population on the spent substrate of the agaric-mushroom cultivation (느타리버섯 폐배지에 대한 줄지렁이(Eisenia fetida) 개체군의 섭식률 및 생장률)

  • Bae, Yun-Hwan;Yang, Yong-Un
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.18 no.4
    • /
    • pp.45-53
    • /
    • 2010
  • Feeding rate and growth rate of earthworm population on the variously pretreated spent materials of the agaric-mushroom cultivation were investigated. When the spent mushroom substrates with different aging periods were supplied to earthworm, feeding rate and growth rate of earthworm population on spent mushroom substrates aged less than 10 days were higher than that on spent mushroom substrates aged more than 20 days. Feeding rate and growth rate were not increased when the spent mushroom substrate mixed with vermicasts or nitrogenous fertilizer was supplied. Feeding rate and growth rate on the ground mushroom substrate were higher than that on the non-ground mushroom substrate. Especially when the ground mushroom substrate was mixed with rice bran and supplied to earthworms, growth rate was much higher than that on the non-ground spent mushroom substrate; it increased 1.85 times.

Temperature-dependent Oviposition Model and Life Table Parameters of Paromius exiguus (Distant) (Hemiptera: Lygaeidae) Growing on Rice (벼에서 흑다리긴노린재 [Paromius exiguus (Distant)] (Hemiptera: Lygaeidae) 산란모델 및 생명표)

  • Park, Chang-Gyu;Park, Hong-Hyeon;Seo, Bo Yoon
    • Korean journal of applied entomology
    • /
    • v.56 no.4
    • /
    • pp.387-394
    • /
    • 2017
  • Temperature-dependent oviposition model and life table parameters of Paromius exiguus (Distant), the causal agent of 'pecky' rice grain were examined at eight constant temperatures (17.5, 20, 22.5, 25, 27.5, 30, 32.5, and $35{\pm}^{\circ}C$) and a photoperiod of 14:10 (L:D) h. Unit functions of the oviposition model were developed and life table parameters were estimated. The longevity of P. exiguus adults decreased with increasing temperature (123.8 days at $17.5^{\circ}C$ and 23.6 days at $32.5^{\circ}C$). Total fecundity was highest at $30^{\circ}C$ (585.2 eggs/female) and lowest at $17.5^{\circ}C$ (21.5 eggs/female). In order to develop a temperature-dependent oviposition model, adult aging-rate, temperature-dependent fecundity, age-specific survival rate, and age-specific cumulative oviposition rate equations were estimated. All unit equations ($r^2=0.92{\sim}0.98$) except for the temperature-dependent fecundity equation ($r^2=0.83{\sim}0.85$), described oviposition characteristics of P. exiguus adequately. Life table parameters of P. exiguus were estimated at various constant temperatures. Net reproduction rate ($R_0$) was highest at $30^{\circ}C$ (118.21). Mean generation time (T) was shortest at $32.5^{\circ}C$ (32.99 days) and doubling time (Dt) was shortest at $30^{\circ}C$ (5.69 days). The highest values of intrinsic rate of increase ($r_m$) and finite rate of increase (${\lambda}$) were 0.122 and 1.129 at $30^{\circ}C$, respectively.

The Transition of Fertility and the Depopulation by the Stage Migration: A case study of Jeollabuk-do (단계적 인구이동에 따른 출산력 변화와 과소화: 전라북도를 사례로)

  • Lee, Chungsup;Kim, Sung Hwan
    • Journal of the Korean Geographical Society
    • /
    • v.49 no.5
    • /
    • pp.728-746
    • /
    • 2014
  • The purpose of this study is to analyze the influence of the selective migration of young age group and the stage migration which has proceeded through generations, on the transition of fertility and the population growth in the rural and urban in the case of Jeollabuk-do. For this, we use O-D matrix of 20-34 age group, the distribution of that group and women of child bearing age, and vital statistics in 1970-2010. The major findings of this study are as follows. First, the outflows from their birth place are common and dominant features of 20-34 age group in each time. Second, there is the stage migration which preceding generation moved from the rural areas to the cities in Jeollabuk-do and following generation has moved from the cities to Seoul metropolitan area. Third the selective outflow migration of young age group has leaded to reduction of the childbearing population, declining birthrate, aging and natural population decline. Due to the stage migration, these depopulation processes occurred in rural area in the past, and currently it expands to the cities with about 15 years time gap. In fact, there have been the natural population decrease which annual number of deaths exceed that of births from the late 1980s in the most rural areas and in the early 2000s, such a phenomenon has been confirmed also in urban areas. Therefore, this study concludes that the stage migration through generations is one of the crucial factor to the population growth in local cities and also brings out the step-wise population decrease in settlement hierarchies.

  • PDF

Syntaxonomical Characteristics of Abandoned Paddy Fields by Seral Stages in South Korea (우리나라에서 휴경기간에 따른 묵논의 군락분류 및 특성)

  • Shim, In-Su;Kim, Hong-Bong;Cho, Kwang-Jin
    • Korean Journal of Environmental Agriculture
    • /
    • v.32 no.3
    • /
    • pp.185-192
    • /
    • 2013
  • BACKGROUND: As a result of rural exodus, aging of rural population, development of high-yield rice varieties and so on, abandoned paddy fields of South Korea have generally increased. The phytosociological studies are needed to recommend the effective vegetation management methods of abandoned paddy fields. The current study performed an analysis of vegetation characteristics by classifying plant communities for abandoned paddy fields in South Korea. METHODS AND RESULTS: A comparative analysis of syntaxonomy, synecology, and syndynamics was performed by using the Z.-M. method of phytosociology and vegetation survey which was obtained from an enumeration district of total 203 phytosociological releves of 5 regions in Gangwon-do, 5 regions in Gyeonggi-do, 2 regions in Chungcheong-do, 18 regions in Gyeongsang-do, and 10 regions in Jeolla-do. Alopecurus aequalis community, Juncus effusus var. decipiens community and Salix koreensis community were, respectively, identified as successional plant communities of the early stage, the middle stage, and the late stage in the vegetation of abandoned paddy field. Sere of abandoned paddy field can be classified, developmentally, into annual plant stage, perennial plant stage, shrub plant stage, and forest tree stage. Several kinds of dominant species rather than a distinct species were found in the middle stage of abandoned paddy field. CONCLUSION(S): In this study, changing pattern in vegetational communities of abandoned paddy field were understood. These results will provide important information for restoring and conserving the ecology of fallow ground.

The Estimated Dietary Fiber Intake of Korean by Age and Sex (한국인의 연령과 성별에 따른 식이섬유 섭취 상태)

  • Lee, Hye-Jung;Kim, Young-Ah;Lee, Hye-Sung
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.35 no.9
    • /
    • pp.1207-1214
    • /
    • 2006
  • The purposes of this study were to determine the estimated dietary fiber (DF) intakes per capita/day of Korean as of 2001 by age groups and sex, and to analyze the major food sources of DF using the data on per capita consumption of each food reported in the 2001 Reports of Korean National Nutrition Survey and the newly-established DF database. The mean daily intakes of DF of Korean increased with increasing age until 49 years and thereafter decreased with aging. The intakes of DF/1,000 kcal increased with increasing age until 64 years and thereafter decreased with aging. On the average, the Korean people under age of 49 did not meet adequate intake (AI) of DF (12 g/1,000 kcal) in Dietary Reference Intakes (DRI) for the Koreans. The male people less satisfied the AI than the female did. The major food groups contributed to DF intakes of Korean adults were high in the order of vegetables, cereals, fruits, seasonings, legumes and seaweeds. Regardless of age and sex, vegetables, cereals and fruits were three major sources of DF for Koreans who obtained approximately 75% of DF from those sources. It has been shown that rice was the first single food source of DF intake for the age groups less than 12 years, however Kimchi was the first major source for all the age groups over 12 years. The infant and elderly groups obtained more DF from 10 major single food sources than the other age groups did. The results of the study revealed that the present levels of DF intakes of Korean in all age groups except the elderly group are insufficient to meet the AI for DF. Therefore the beneficial effects of DF on health and the increased consumption of DF from the variety of food sources should be emphasized through the continuous nutritional education.

Reaction of Near-Isogenic Lines with Resistance to Bacterial Blight to Korean and Japanese isolates of Xanthomonas oryzae pv. oryzae (한국 및 일본 균주에 대한 벼흰잎마름병 저항성 근동질 유전자 계통의 반응)

  • Kim, Bo-Ra;Yang, Cheol-Woo;Jin, Xuan-Ji;Han, Jin-Soo;Lee, Eun-Jeong;Choi, Jae-Eul
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.52 no.1
    • /
    • pp.89-99
    • /
    • 2007
  • To develop durable and stable breeding strategies far the control of rice bacterial blight (BB) disease, the near-isogenic lines (NILs) with diverse resistance genes to BB isolates were evaluated in plant at three different growth stages using four Korean ($K_1,\;K_2,\;K_3,\;K_{3a}$) and three Japanese isolates (I, II, III). The resistance of the NILs to seven BB isolates tended to increase with plant aging. At the seedling stage, the NILs with single resistance genes were mostly resistant to $K_1$ race but they showed partial or no resistance to other isolates. A NILs (IRBB5) possessing xa5 had full resistance to the four Korean isolates, illustrating that it is a useful source to give enhancement to Korean breeding program. At the maximum tillering stage, resistance of NILs to $K_2,\;K_3$, I and II isolates considerably increased while resistance to $K_1,\;K_{3a}$ and III were similar to those of seedling stage. NILs with resistance gene of Xa4, xa5 and Xa7 proved to be the most stable to BB isolates at the maximum tillering stage. At the heading stage, most resistance genes of NILs were effective against BB isolates, and xa5 showed the consistent resistance to all the BB isolates including $K_{3a}$ and III isolates, demonstrating that resistance genes of Xa4, xa5 and Xa7 can be used either alone or combined to enhance resistance to BB disease in Korea.

The Transmission Activities and characteristic of the Naeseo Traditional Folk art Conservation Association in Masan (마산 내서전통민속문화예술보존회의 전승 활동과 특징)

  • Choi, Ja-Un
    • (The) Research of the performance art and culture
    • /
    • no.43
    • /
    • pp.121-143
    • /
    • 2021
  • The Aim of the this paper is to figure out impetus of the Naeseo Traditional Folk art Conservation Association. This Preservation Society derived from Hogaeri farmers' band. Through aging and hollowing out Hogaeri farmers' band got into a period of stagnation. In order to overcome slump villager and people of a township organized a conservation society in 1994. Members restored and directed folk song which from age to age for performance. are designated as cultural asset in 2017. Sutguldeong song is only song in inland area. This song are worthy of notice in . which is consist of various agricultural work songs experienced two changes. Rice-planting songs are characteristic. Especially, Executive playing a central role harden foundation of the Preservation Society. The mainspring of activity is the sense of responsibility. Preservation Society laying emphasis on recruiting new members. Preservation Society is planning to develop curriculum for Jurisdiction elementary and middle school students. This Preservation Society is made up of First generation members and Second generation members. First generation members who are born and bred in Hogaeri have been good friends both in joy and in sorrow Early days of Preservation Society. So, They has a strong family bond. In order to induce membership Members are practicing Nongak, popular folk songs, dancing program. Second generation members are not conversant with a folk song. Nonetheless They have a strong mind on a member line.