• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1308-1318
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• 2014

The specific freshwater environment of reservoirs formed by streams has not been well studied. In this paper, the bacterioplankton community in such a reservoir, the Huangqian Reservoir in eastern China, was described using culture-independent molecular methods. We found that the most dominant bacterioplankton were affiliated with Cyanobacteria, followed by Betaproteobacteria, Bacteroidetes, Gammaproteobacteria, and Actinobacteria. Both bacterial abundance and diversity increased along the direction of water flow, and the 16S rRNA gene copy number in the water outlet was nearly an order of magnitude higher than that in the water inlet. Pearson correlation analyses indicated that nitrate had a significantly negative correlation with the bacterial abundance (p < 0.05) and that ammonium was positively correlated with bacterial abundance (p < 0.05). Interestingly, owing to a remarkably negative correlation (p < 0.01), the ratio of nitrate and ammonium might serve as a good pre dictor of the relative abundance of bacterioplankton. According to redundancy analysis, nitrate and dissolved oxygen were the major factors influencing the bacterial communities. In addition, we attempted to determine the reasons why such a reservoir could maintain good ecological balance for a period of decades, and we found that the environmental factors and bacterial communities both played critical roles. This research will benefit our understanding of bacterial communities and their surrounding environments in freshwater ecosystems.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.107-112
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• 2000

Comparison of oribatid mite community structures among Namsan, Kwangreung, and Mt, Jumbong, which receive different levels of environmental stress from severe to almost none, was made in coniferous and deciduous forests, respectively. The number of species of oribatid mites was significantly lower in Namsan and Mt. Jumbong than in Kwangreung in the coniferous forest (p<0.05). In the deciduous forests, the number of species of oribatid mites was significantly lower in Namsan than in Kwangreung and Mt. Jumbong. Dominant species in 3 regions were remarkably different. Similarity of the oribatid community between Namsan and Kwangreung was much higher (ca. 2 times) than similarities between Namsan and Mt. Jumbong. and Kwangreung and Mt Jumbong. Diversity index (H$^{\prime}$) value of oribatid communities in deciduous forests in Namsan, Kwangreung and Mt. Jumbong was 2.74, 2.78, and 2.87, respectively. Diversity (H$^{\prime}$) value of oribatid communities in coniferous forests in Namsan, Kwangreung and Mt. Jumbong was 2.83, 2.62, and 2.38, respectively. Namsan and Kwangreung were characterized as O-type in both coniferous and deciduous forests On the contrary, Mt. Jumbong was characterized as MG-type in MGP-I analysis.

• The Korean Journal of Community Living Science
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• v.28 no.4
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• pp.669-686
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• 2017

This study reinterpreted the value of traditional communities in rural areas and explored ways to revitalize sustainable communities. To do this, we surveyed the members' perceptions about the activities of the community organization as assessed through a questionnaire. The questionnaire items focused on the participation, satisfaction and contribution of the members of the community organization, with additional questions investigating the idea of the community vitalizations plan. A self-report questionnaire survey was administered to 321 members of the community, and the results were analyzed through technical data, t-test and ANOVA analysis by using the SPSS program. In the results, the perceptions of the members of the traditional village community differed significantly according to socio - demographic factors and member recognition characteristics. Especially, males were more voluntarily and positively compared to females, and the lower the age of satisfaction, the lower was the perceived individual satisfaction with community activities. In the case of perceived contributions to individuals and the community, the participants perceived positively in the emotional support for the individual's participation in the organization. On the other hand, the results confirmed that the contribution to the local community is important in realistic aspects such as regional vitalizations. It is confirmed by the decrease in the number of members in response to the difficulty of the organization. (Ed- 'the lack of the size of the membership' simply repeats 'the decrease in the number of members'; thus it's unnecessary).

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.4
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• pp.17-24
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• 2009

To ensure the revitalization of rural communities with viable levels of population, various agricultural policies are needed. Attaining this goal demands a comprehensive plan to improve rural housing conditions in general, along with more proactive policies dealing with existing rural housing problems by providing public housing options. The purpose of this paper is to suggest a set of base data which can provide direction when proposing prospective housing policies which comply the peculiar and changing needs of rural communities. To establish the base data, the study reviewed all the relevant issues, requirements and resources in the course of developing rural housing regulations and policies. Some municipal organizations have implemented independent housing programs for returning farmers. They provide one-stop service corners to provide returning farmers comprehensive counseling and information about employment, child-rearing and education, housing, and etc. in their municipals. Agricultural housing projects nowadays focus on promoting voluntary establishments of local communities by providing comprehensive plans for public housing, idyllic housing and other interchange facilities. Recent trends on housing project take into consideration both residential areas and their surrounding landscapes at minimum investment possible. The efficient investment of regional housing development lies in the simultaneous consideration on both the construction and operation and management of housing development from beginning to end.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.3-16
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• 2004

The objective of this study was to investigate the necessity of rural tourism education in the Korea National Agricultural College and suggest the educational plan. Recently, the Korean government proposes the rural tourism as an alternative plan for solving the problems of agriculture and rural community that experience difficulty by the opening of agricultural market and the falling price, etc. As result of investigation of cases of OECD nations and the growth rate of tourism market in Korea, it has been determined that the demand of rural tourism was sufficient. The Ministry of Agriculture & Forestry makes a goal of attracting the yearly 150million tourists by 2013 to the rural communities. Rural tourism can be new income source in the rural communities in Korea. It is important to develop the resources in the rural amenity and promote the tourism leader group with it that will be applicable in the field in order that this rural tourism may take its place as main source of income. As a result of research, on the characteristics of the Korea National Agricultural College that the demand of manpower about the rural tourism and the most of students settled down on the rural community after their graduation, it has been determined that the education for rural tourism leaders in the Korea National Agricultural College would authenticate the validity. Also, it suggested the educational plan by the curriculum for the education for the rural tourism leaders, and suggested the necessity of the establishment of the department of rural tourism. The establishment of the department of rural tourism in the Korea National Agricultural College should be investigated and determined carefully through the relations with the other departments and the process of collecting the public opinions within and outside schools, etc.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.293-299
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• 2010

The aim of this study was to investigate the possible impact of Bt Chinese cabbage on the soil microbial community. Microbial communities were isolated from the rhizosphere of one Bt Chinese cabbage variety and four varieties of conventional ones and were subjected to be analyzed using both culture-dependent and molecular methods. The total counts of bacteria, fungi, and actinomycetes in the rhizosphere of transgenic and conventional Chinese cabbages were observed to have an insignificant difference. Denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes revealed that the bacterial community structures were very similar to each other and this genetic stability of microbial communities was maintained throughout the culture periods. Analysis of dominant isolates in the rhizosphere of transgenic and conventional Chinese cabbages showed that the dominant isolates from the soil of transgenic Chinese cabbage belonged to the Bacilli and Alphaproteobacteria, while the dominant isolates from the soil of conventional cabbage belonged to the Holophagae and Planctomycetacia, respectively. These results indicate that the Bt transgenic cabbage has no significant impact on the soil microbial communities.

• Journal of Korean Society of Rural Planning
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• v.29 no.1
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• pp.69-79
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• 2023

Uiseong-gun, Gyeongsangbuk-do, one of the representative small rain regions, has developed a traditional irrigation farming system while overcoming and adapting to unfavorable agricultural environments from the days of the ancient nation of Jomunguk to the present. In 2018, its value was recognized and designated as Nationally Important Agricultural Heritage System No. 10. This study was conducted with the purpose of examining the characteristics of the traditional irrigation farming system in Uiseong from the viewpoints of irrigation facilities, irrigation communities, and agricultural activities. The research results are as follows. Uiseong-gun has been expanding irrigation facilities for agriculture since long ago, and it has been investigated that a total of 6,227 irrigation facilities are currently distributed along the Wicheon water system that crosses Uiseong-gun from east to west. Irrigation facilities appear differently depending on the topography. The irrigation facility has a 'su-tong' as an irrigation passage and a corkscrew structure 'mot-tchong' as a water quantity control device, so the amount of water was adjusted as needed. Through this facility, surface water with warmer temperature is supplied to the farmland to prevent cold damage to crops. Uiseong has developed activities to organize irrigation communities in one village or several villages to secure agricultural water from an early age. Currently, this tradition continues, and a total of 213 irrigation communities manage 375 irrigation facilities (6.0% of all irrigation facilities). Through this organization, called Mong-ri-gye, water for agriculture is obtained, managed, and distributed equitably. In order to increase agricultural production, Uiseong implemented double cropping by converting rice fields and fields. In the case of Mt. Geumseong, double cropping of rice and barley was mainly carried out until the 1970s, but since the 1980s, double cropping of rice and garlic has been implemented with higher income. One of the unique features of the agricultural system of this region is the spectacular landscape that changes simultaneously from field to rice field in spring and from rice field to field in autumn.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.1
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• pp.11-20
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• 2014

Many classification studies for the community of densely-connected nodes are limited to the comprehensive analysis for detecting the communities in probabilistic networks with nodes and edge of the probabilistic distribution because of the difficulties of the probabilistic operation. This study aims to use convolution method for operating nodes and edge of probabilistic distribution. For the probabilistic hierarchy network with nodes and edges of the probabilistic distribution, the model of this study detects the communities of nodes to make the new probabilistic distribution with two distribution. The results of our model was verified through comparing with Monte-carlo Simulation and other community-detecting methods.

• Journal of agricultural medicine and community health
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• v.45 no.1
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• pp.41-46
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• 2020

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.442-450
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• 2015

This study was conducted to investigate the effect of Psy-2A-CrtI (PAC), a genetically modified (GM) rice with enhanced ${\beta}$-carotene, on the soil microbial community. The soil used to cultivate GM rice and its wild-type, Nakdong, was analyzed for population density, denaturing gradient gel electrophoresis (DGGE), and pyrosequencing. It was found that the bacterial, fungal and actinomycetes population densities of the PAC soils were within the range of those of the non-GM rice cultivar, Nakdong. The DGGE banding patterns of the GM and non-GM soils were also similar, suggesting that the bacterial community structures were stable within a given month and were unaffected by the presence of a GM plant. The pyrosequencing result showed a temporal difference in microorganism taxon and distribution ratio, but no significant difference between GM and non-GM was found. The persistence of the transgene DNA in the plant and surrounding soil were investigated for different time periods. There were differences in the persistence within the plant depending on the gene, but they could not be detected after 5 weeks. Also the transgenes were not detected in the surrounding soil. These results indicate that soil microbial communities are unaffected by the cultivation of a PAC rice within the experimental time frame.