• Korean Journal of Microbiology
• /
• v.51 no.1
• /
• pp.81-85
• /
• 2015

Since the banning of antibiotic growth promoters (AGPs), the death of livestock has been increased, thus there is a strong demand for AGP-alternatives. Modulation of gut microbiota has been reported to affect host physiological functions and suggested to be a novel approach for developing AGP-alternatives. However, little has been understood about livestock gut microbiota compared to that of humans. We conducted preliminary study provide fundamental information regarding to regional differences in swine gut microbiota. Swine fecal samples were obtained from farms in Jeju (n=40), Gwangju (n=28), and Haenam (n=30). MiSeq was used to sequence 16S rRNA V4 region, and Mothur pipeline (Schloss et al., 2009) was used for data processing. A total of 5,642,125 reads were obtained and 3,868,143 reads were remained after removing erroneous reads. Analysis of taxonomic composition at the phylum level indicated greater abundance of Firmicutes among Jeju swine, and cluster analysis of distribution of operational taxonomic units also showed regional differences among swine gut microbiota. In addition, correlation analysis between non-metric multidimensional scaling and abundance of phyla suggested that the phyla Actinobacter, Verrucomicrobia, Firmicutes, and Fibrobacteres were driving factors for the regional differences. Livestock gut microbiota may be affected by diet and practices in farms. Our results indicated significant regional differences in swine gut microbiota, suggesting that future livestock gut microbiota studies should be designed with the regional differences in mind.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.3 no.4
• /
• pp.215-219
• /
• 2001

Land surface parameterization schemes for atmospheric models as well as decision support tools for ecosystem management require a frequent updating of land cover classification data for regional to global scales. Rice paddies have not been treated independently from other agricultural land classes in many classification systems, despite their atmospheric and ecological significance. A simple but improved method over conventional land cover classification schemes for rice paddy is suggested. Normalized difference vegetation index (NDVI) was calculated for the land area of South Korea at a 1km by 1 km resolution from the visible and the near-infrared channel reflectances of NOAA-AVHRR (Advanced Very High Resolution Radiometer). Monthly composite images of daily maximum NDVI were prepared for May and August, and used to classify 4 major land cover classes : urban, farmland, forests and water body. Among the pixels classified as "forests" in August, those classified as "water body" in May were assigned a "rice paddy" class. The distribution pattern of "rice paddy" pixels was very similar to the reported rice acreage of 1,455 Myons, which is the smallest administrative land unit in Korea. The correlation coefficient between the estimated and the reported acreage of Myons was 0.7, while 0.5 was calculated from the USGS classification.calculated from the USGS classification.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.11 no.2
• /
• pp.79-85
• /
• 2009

Net radiation ($R_N$) is a driving force of biological and physical processes between the surface and the atmosphere and its knowledge is critical to weather forecasting and water resource management. The measurement of $R_N$ is, however, scarce and it is typically estimated from an empirical relationship. This study presented two different methods of $R_N$ estimation over three major plant functional types (i.e., a deciduous forest, a coniferous forest, and a farmland) in Korea. One is a linear regression method between $R_N$ and solar radiation and the other is a radiation balance method. The two methods were examined using the data collected in 2008 at the three sites. Based on the linear regression method over a year, $R_N$ was 70% of the incoming shortwave radiation ($R_S{\downarrow}$) for a deciduous forest, 79% for a coniferous forest, and 64% for a farmland, indicating that the relationship was plant functional type-specific. For the radiation balance method, the inclusion of longwave radiation component slightly improved $R_N$ estimations. Overall, there was a good agreement between the observed and the estimated $R_N$ from both methods, indicating a reliable applicability of the two methods in estimating $R_N$.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.22 no.3
• /
• pp.176-182
• /
• 2020

National Institute of crop Science of the Rural Development Administration (RDA) has conducted long-term monitoring studies to find out the relationship between crop yield and climatic factors for major food crops including rice. Rice growth and y ield have been monitored in 17 regions where the branches of the National Institute of Crop science and the Provincial Agricultural Research and Extension Service locate. The data obtained from monitoring studies for rice growth and yield include the observation of vegetative growth status and yield components, which include leaf number, biomass and the weight of 1000 grains. These data have been collected from rice fields where standard management procedures have been applied. The observation data for crop growth and yield monitoring studies from 1999 to 2019 are open to public through agricultural science library operated by RDA.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.3
• /
• pp.271-279
• /
• 1991

The changes in fat acidity of brown rice and eating quality of rice during long term grain storage of unhulled rice were evaluated for the government managed rices. The Tongil type rice grains had consistently significantly lower fat acidity during three and half year storage than the Japonica type rice. On sensory evaluation of the fresh milled cooked rice the eating quality of the long term stored rices, 1987, 1988, and 1989 produce Tongil did not differ much each other even though increase in fat acidity by year of storage. The Japonica rices produced in 1989 and 1990 in different locations and stored there also did not differ much in eating quality. The grains stored in storehouses of super grade did not differ significantly from those stored in the first grades, but the grains stored (4 $^{\circ}C$, RH 50%) grains have kept the eating quality almost same as the fresh grains even after two and half years. A higher degree of milling did not improve significantly the sensory taste of cooked rice of the grains long term stored.

• Journal of Bio-Environment Control
• /
• v.29 no.3
• /
• pp.277-284
• /
• 2020

To increase the utilization of the intelligent methodology of smart farm management, estimation modeling techniques are required to assess prior examination of crops and environment changes in realtime. A mandatory environmental factor such as CO₂ is challenging to establish a reliable estimation model in time domain accounted for indoor agricultural facilities where various correlated variables are highly coupled. Thus, this study was conducted to develop an artificial neural network for reducing time complexity by using environmental information distributed in adjacent areas from a time perspective as input and output variables as CO₂. The environmental factors in the smart farm were continuously measured using measuring devices that integrated sensors through experiments. Modeling 1 predicted by the mean data of the experiment period and modeling 2 predicted by the day-to-day data were constructed to predict the correlation of CO₂. Modeling 2 predicted by the previous day's data learning performed better than Modeling 1 predicted by the 60-day average value. Until 30 days, most of them showed a coefficient of determination between 0.70 and 0.88, and Model 2 was about 0.05 higher. However, after 30 days, the modeling coefficients of both models showed low values below 0.50. According to the modeling approach, comparing and analyzing the values of the determinants showed that data from adjacent time zones were relatively high performance at points requiring prediction rather than a fixed neural network model.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.44 no.6
• /
• pp.1-12
• /
• 2016

There is growing concern about landscape agreement with regard to a variety of activities within resident-based agreements in Korea. This study aims to investigate the communication method of the agreement contacting process and its essential role as a bottom-up resident-based process. The study site is Gobuk Market in Suwon city, where a resident-based landscape agreement was successfully made. In this study, the author implemented in-depth interviews and a literature review to understand the meaning of the agreement contracting process and participants' opinions regarding the Gobuk Market case. During the landscape contracting process, the level of participation of residents, experts and the government changed. The study found that diverse communication methods, such as training, agreement information sessions and seminars were conducted during the process of the resident-based landscape agreement and it is crucial to construct healthy relationship among stakeholders. Furthermore, the experts' role is crucial in establishing agreement among residents initially. However, as local empowerment and the willingness of local people grow, each stakeholder's role is changed by stage. Therefore the Central and Local Government have the necessary task of providing institutional strategy. This study has offered practical information on how each stakeholder played their individual role within the landscape agreement.

• Journal of Wetlands Research
• /
• v.16 no.3
• /
• pp.441-450
• /
• 2014

In this study, we consider ability of self-purification for a rational water quality management. And we assess the risk of Alkyl Benzene Sulfonic acid sodium salt(ABS) of harmful ingredients in Anseong Cheon watershed using QUAL2E model. The observations and simulated results were fitted well for BOD and ABS, but even though the trend of DO concentration change was well represented, the error between observation and simulation values was existed. We assessed the Risk assessment by calculating Risk quotient(RQ) by Predicted Exposure Concentration(PEC) and Predicted No-Effect Concentration(PNEC). Results of the impact of ABS on the self-purification of the river were Anseongcheon[0.0003(Bressan), 0.06(Criteria of Ministry of environment)], Jinwicheon[0.0002(Bressan), 0.04(Criteria of Ministry of environment). And result of the impact of ABS on the Aquatic ecosystem of the river were Anseongcheon[0.0667(Bressan), 0.005(Criteria of Ministry of environment)], Jinwicheon[0.1(Bressan), 0.0075(Criteria of Ministry of environment). All of these results were smaller than the 1.0 which is the reference value suggested by Norification No.30 of the National Institute of Environment Research. So, ABS did not affect a self-purification and aquatic ecosystem of the river. The method suggested in the study is a simple one and can provide more information for harmful ingredients than criteria of Ministry of environment.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.1 no.1
• /
• pp.12-19
• /
• 1999

CERES-rice, a rice growth simulation model, was used in conjunction with daily weather data to figure out the spatial variation of the phenology and yields of paddy rice at 168 rice cultivation zone units(CZU) of Kyunggi Province in 1997. Two sets of cultivar specific coefficients, which represent early and mid-season maturing varieties, were derived from field experiments conducted at two crop experiment stations. The minimum data set to run the model for each CZU (daily maximum and minimum temperature, solar irradiance, and rainfall) was obtained by spatial averaging of existing 'Digital Map of Korean Climate'(Shin et al., 1999). Soil characteristics and management information at each CZU were available from the Rural Development Administration. According to a preliminary test using 5 to 9 years field data, trends of the phasic development(heading and physiological maturity), which were obtained from the model adjusted for these coefficients, were in good agreement with the observed data. However, the simulated inter-annual variation was somewhat greater than the reported variation. Rough rice yields of the early maturing cultivar calculated by the model were comparable with the reported data in terms of both absolute value and inter -annual variation. But those of the mid season cultivar showed overestimation. After running the simulation model runs with 1997 weather data for 168 CZU's, rough rice yields of the 168 CZU's calculated by the model were aggregated into corresponding 33 counties by acreage-weighting to facilitate direct comparison with the reported statistics from the Ministry of Agriculture and Forestry. The simulation results were good at 22 out of the 26 counties with reportedly increasing yield trend with respect to the past 9 years average.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.9 no.2
• /
• pp.109-120
• /
• 2007

The information on flowpath, storage, residence time, and interactions of water and carbon transport in a catchment is the prerequisite to the understanding and predicting of water and carbon cycling in the mountainous landscapes of Korea. In this paper, along with some up-to-date results, we present the principal methods that are currently used in HydroKorea and CarboKorea research to obtain such information. Various catchment hydrological processes have been examined on the basis of the water table fluctuations, the end-member mixing model, the cross correlation analysis, and cosmogenic radioactive isotope activity. In the Gwangneung catchment, the contribution of surface discharge was relatively large, and the changes in the amount, intensity and patterns of precipitation affected both the flowpath and the mean residence time of water. Particularly during the summer monsoon, changes in precipitation patterns and hydrological processes in the catchment influenced the carbon cycle such that the persistent precipitation increased the discharge of dissolved organic carbon (DOC) concentrated in the surface soil layer. The improved understanding of the hydrological processes presented in this report will enable a more realistic assessment of the effects of climate changes on the water resource management and on the carbon cycling in forest catchments.