• Journal of The Korean Society of Agricultural Engineers
• /
• v.63 no.2
• /
• pp.85-96
• /
• 2021

Irrigation return flow is defined as the excess of irrigation water that is not evapotranspirated by direct surface drainage, and which returns to an aquifer. It is important to quantitatively estimate the irrigation return flow of the water cycle in an agricultural watershed. However, the previous studies on irrigation return flow rates are limitations in quantifying the return flow rate by region. Therefore, simulating irrigation return flow by accounting for various water loss rates derived from agricultural practices is necessary while the hydrologic and hydraulic modeling of cultivated canal-irrigated watersheds. In this study, the irrigation return flow rate of agricultural water, especially for the entire agricultural watershed, was estimated using the SWMM (Storm Water Management Model) module from 2010 to 2019 for the Madun reservoir located in Anseong, Gyeonggi-do. The results of SWMM simulation and water balance analysis estimated irrigation return flow rate. The estimated average annual irrigation return flow ratio during the period from 2010 to 2019 was approximately 55.3% of the annual irrigation amounts of which 35.9% was rapid return flow and 19.4% was delayed return flow. Based on these results, the hydrologic and hydraulic modeling approach can provide a valuable approach for estimating the irrigation return flow under different hydrological and water management conditions.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.42-42
• /
• 2017

Prediction of rice yield during a growing season would be very helpful to magnify rice yield as it also allows better farm practices to maximize yield with greater profit and lesser costs. UAV imagery based automatic detection of rice can be a relevant solution for early prediction of yield. So, we propose an image processing technique to predict rice yield using low altitude UAV images. We proposed $L^*a^*b^*$ color space based image segmentation algorithm. All images were captured using UAV mounted RGB camera. The proposed algorithm was developed to find out rice grain area from the image background. We took RGB image and applied filter to remove noise and converted RGB image to $L^*a^*b^*$ color space. All color information contain in both $a^*$ and $b^*$ layers and by using k-mean clustering classification of these colors were executed. Variation between two colors can be measured and labelling of pixels was completed by cluster index. Image was finally segmented using color. The proposed method showed that rice grain could be segmented and we can recognize rice grains from the UAV images. We can analyze grain areas and by estimating area and volume we could predict rice yield.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.51 no.5
• /
• pp.87-94
• /
• 2009

The objectives of this paper were to estimate cell based pollutant loadings for total maximum daily load (TMDL) programs and to evaluate the applicability of the agricultural nonpoint source (AGNPS) model for an intensive agricultural watershed in Korea. The model was calibrated and validated at a watershed of 384.8 ha of drainage area using the observed data from 1996 through 2000 in terms of runoff, suspended solid, total nitrogen, and total phosphorus on a hourly basis. Analysis of spatial variations of pollutant loadings for rainfall frequencies of various intensities and durations were conducted. In addition, the validated model was applied to estimated the TMDL removal efficiency for best management practices (BMPs) scenarios which were selected by taking into account the pollutant characteristics of the study watershed. The model can help to understand the problems and to find solutions through landuse changes and BMPs. Thus, the method used for this study was able to identify TMDL quantitatively as well as qualitatively for various sources pollution that are spatially dispersed. Also it provides an assessment of the impact of BMPs on the water bodies studied, allowing the TMDL programs to be complemented more effectively.

• Journal of Environmental Policy
• /
• v.2 no.2
• /
• pp.17-40
• /
• 2003

The objective of this paper is to formulate strategies and action programs for developing sustainable agriculture in Korea. There is increasing evidence that agriculture has been preoccupied with increasing productivity much to the detriment of environmental degradation. The issue of increasing agricultural productivity so as not to undermine the environment is a difficult task. In reality, there are many definitions of sustainable agriculture and sustainable agricultural development. In this paper, sustainable agriculture is defined by its ability to ensure future supplies of agricultural products at acceptable economic and environmental costs to the society. Sustainable agriculture development refers to the optimal level of interaction among the three dimensions - the environmental, the economic and the social - through dynamic and adaptive processes of trade-off. In order to formulate the strategies for developing sustainable agriculture, three stage approaches such as strategic analysis, strategic choice, and strategic implementation are employed. The basic framework for strategies of sustainable agriculture development consists of five steps such as vision, targets, principles, action plan and policy instruments. The major action plans for activating formulated strategies are suggested as integrating agricultural and environmental policy measures, establishing the system of optimal agri-environmental resources management practices, establishing safe and high quality product system and its effective marketing system, increasing the R&D investment for developing sustainable agro-technology, developing indicators for measuring sustainable agricultural development, and taking a share in related roles for all parties including farmers, consumers, policy makers, researchers and NGOs.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.47 no.4
• /
• pp.75-85
• /
• 2005

A study was performed to examine the effects of reclaimed-water irrigation on microorganism con-centration in ponded-water of paddy rice plots. Several treatments were used and each one was triplicated to evaluate the change of indicator microorganisms (total coliforms (TC), fecal coliforms FC), and E. coli) concentrations in 2003 and 2004 growing seasons. Their concentrations increased significantly right after irrigation, but decreased about $45\%$ in 24 hours. It implies that agricultural activities such as plowing and fertilizing should be practiced one or two days after irrigation considering health-risks. Treatments with UV-disinfected water irrigation demonstrated significantly lower concentrations than others including control plots where natural surface water was irrigated. The monitoring results from actual paddy rice fields and experimental paddy plots showed that concentrations of indicator microorganisms ranged from $10^2\;to\;10^5$ MPN/100mL. A comprehensive assessment of existing agricultural practices and a thorough monitoring in the field as well as treatment-plots are recommended to make more realistic national guidelines more applicable. UV-disinfected water irrigation reduced microorganism concentrations in paddy fields down to below the concentration of conventional paddy rice culture, and is thought to be an effective and feasible measure fur agricultural reuse of secondary effluent.

• Korean Journal of Organic Agriculture
• /
• v.21 no.2
• /
• pp.139-155
• /
• 2013

The purpose of this study is to analyze the effects of abolishing the low-pesticide agricultural product certification on environmentally friendly farming. A survey was conducted to quantitatively analyze farming practices and factors that change farming practice. It was found that only 17.0% of low-pesticide fruit farmers said that they will change their farming practice into organic or pesticide-free farming. With regard to the factors of farming practice change, binomial logistic regression model was applied for the analysis. In the analysis, it was found that farmers who grow the low-pesticide agricultural product are more likely to change their farming practice into organic or pesticide-free farming, as their expected price of organic or pesticide-free products is high, their area size is small, price premium of low-pesticide agricultural product is low, the frequency of their training is high. It is necessary to enhance the direct payment system to enlarge organic and nonpesticide acreage, and pest management techniques for fruits should be developed for low-pesticide fruit farmers to change their practice into organic and nonpesticide practice. Dissemination of cultivation manual, introduction of insurance to farmers, improvement of certificate system, and advertising and marketing of environment-friendly agricultural products are useful to develop environment-friendly agriculture.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.850-852
• /
• 2011

As safety agricultural product has become more interest, attempt for safety agricultural is more active. One of them is GAP(Good Agricultural Practices) information service. This service is supply system which is agricultural safety supervision of produce to sale. In this paper, This system provide GAP information service using RFID(Radio Frequency Identification) and consequently consumer easily use this system.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.10 no.3
• /
• pp.107-112
• /
• 2008

"Jeung-Bo-San-Lim-Gyeong-Je" (meaning "Revised Forest Management") has been well recognized as the informative document that introduces scientific knowledge and experiences of Korean ancestors regarding weather and climate. The tradition of Gwan-Cheon-Mang-Gi(i.e., empirical forecasting of short-term weather phenomena based on the status of cloud or sky) has been continuously utilized as a civilian weather forecasting method and even for very short-term weather prediction by operational forecasters these days. This agricultural technology textbook, published during the Great King Youngjo in Chosun-Dynasty, may be regarded as a poorly written document from the modern standpoint. Nonetheless, this study demonstrates that by and large the empirical knowledge contained in the book is indeed science based although their applications are limited to several hours for local forecasts in agricultural practices and daily living. For example, the wisdom of keeping water at an optimum level in a paddy field after sowing to prevent young seedlings from late frost damages was not at all different from the present technique of vinyl covered seedling nursery.

• Journal of Agricultural Extension & Community Development
• /
• v.27 no.4
• /
• pp.159-171
• /
• 2020

This study aims to examine the needs analysis for agricultural management capabilities and farming practices that were emphasized by focusing to the inflow of farmers and the importance of the smooth succession. Data were collected from 134 farm successors. The Borich demand and the Locus for Focus model were hired for the study. Result were as follows. The competency group that the farm successors showed a high educational needs for was financial management. As for the detailed competencies that farm successors showed high educational needs for, based on Borich demand and the Locus for Focus model, the six detailed competencies of financial measures, financial analysis, financial management, sales planning, machine operation, and pest management were common and were derived as priorities. As for the direction of farming practice education for farm successors, based on these analysis results, education on machinery operation in the production sector should be expanded, and the management sector, more systematic and diverse education should be prepared to strengthen financial management capabilities.

• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.6
• /
• pp.598-603
• /
• 2014

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic sources, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission in the agricultural field is essential to develop National inventories of greenhouse gases (GHGs) emission. The objective of this study was to develop emission factor to estimate direct $N_2O$ emission from agricultural field by measuring $N_2O$ emissions in the red pepper cultivating field from 2010 to 2012. Emission factor of $N_2O$ calculated from accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0086{\pm}0.00043kg$ $N_2O-N\;kg^{-1}$ N resulted from three year experiment of the research sites. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.