Journal of the Korean Society of Agricultural Engineers publishes peer-reviewed research articles in engineering to help better understand and thus solve problems in agriculture, environment, food and other biological systems. Journal of the Korean Society of Agricultural Engineers presents cutting-edge research on a broad range of topics including irrigation and drainage, soil and water conservation, rural planning and development, agricultural structure & environmental control, rural environment & natural resources management, and more.
Cultivation changes in the paddy fields have an important impact on agricultural drainage planning. For deciding the dimension of agricultural drainage structures, the rainfall-runoff modeling quantifies the probable flooding that meets the drainage standards. This study aimed to propose an inundation damage-based method to determine the design drainage considering cultivation changes in the paddy fields. For this purpose, hydrographs were derived based on the rainfall-runoff modeling, and inundation damages were estimated utilizing three scenarios reflecting cultivation changes. Regarding the 48-hour design rainfall, it was necessary to determine the r coefficient of the Chicago method for design consistency. With the larger proportion of other crops in paddy fields, estimating inundation damage reduction would be more appropriate than the conventional flood-level-based design. The results of this study are expected to be considered as an alternative drainage design method under cultivation changes in paddy fields, while demonstrating further research to analyze the effects of the rainfall duration and the r coefficient on agricultural drainage planning.
Classification of Suitable Sites for Application of Alternative Irrigation Water Systems Utilizing Rainfall-Runoff in Drought-Prone Mid-Mountainous Farmlands in Korea
최지은 Choi Jieun , 김시호 Kim Siho , 이정은 Lee Jeongeun , 김영진 Kim Youngjin , 장민원 Jang Min-won , 황세운 Hwang Syewoon
Classification of Suitable Sites for Application of Alternative Irrigation Water Systems Utilizing Rainfall-Runoff in Drought-Prone Mid-Mountainous Farmlands in Korea
최지은 Choi Jieun , 김시호 Kim Siho , 이정은 Lee Jeongeun , 김영진 Kim Youngjin , 장민원 Jang Min-won , 황세운 Hwang Syewoon
Climate change is leading to an increase in agricultural droughts, with small-scale upland farming areas particularly vulnerable due to their lack of distinct water sources. These scattered mid-mountain regions are especially susceptible to agricultural droughts because they do not have well-defind sources for water extraction. This study aims to identify small-scale upland farming areas in Korea that are vulnerable to agricultural drought and in need of alternative agricultural water sources. To achieve this, evaluation criteria and indicators for irrigation-vulnerable agricultural areas were established, and these areas were extracted and quantitatively presented in terms of area and number of locations. The extracted irrigation-vulnerable agricultural areas cover an area of 10,330.7 ha and consist of a total of 2,635 village-scale farming locations, with the highest concentration of these areas in Gyeonggi-do. Based on this, an altitudinal analysis was conducted, and it was found that areas in Gangwon-do showed a lower rate of area reduction per 100 m elevation interval, while areas in Gyeonggi-do exhibited a higher rate of area reduction. This indicates that the target areas in Gangwon-do are located at relatively higher altitudes, while those in Gyeonggi-do are situated at lower altitudes. The results of this study are expected to serve as foundational data for selecting priority sites for the on-site application of alternative agricultural water systems in the future. Future studies may additionally be conduted to assess the effectiveness and economic viability of applying alternative agricultural water systems to irrigation-vulnerable agricultural areas.
Analysis of SoilㆍWater Quality Changes and Water Saving Effects in Solar Power Pilot District
손재권 Son Jae-gwon , 윤상원 Yoon Sang-won , 송재도 Song Jae-do
This study analyzed the effects of insolation on evaporation and the hazards to soil and water quality in the Buan testbed. For monitoring, weather observation equipment ZL6 and a pressure water level gauge were installed in the target district to investigate the evaporation and soil and water quality samples during the rainy season were collected by season for environmental impact assessment. As a result of the Buan testbed soil environmental impact assessment, the change in the content of hazardous components in the testbed soil heavy metals was found to be lower than the soil pollution concern standards and countermeasure standards, and the water quality environmental impact assessment result showed that the impact on the water quality environment was small. It was found that the insolation inside the solar power plant was affected by 37.11 to 85.83% of the insolation outside the solar power plant, with an average of 58.67% of the insolation and the amount of water saved inside the solar power plant was reduced to 45.61%. In order to select the optimal effect in the future, it is judged that analysis will be necessary according to the panel size for each solar type after installation in the test demonstration complex.
Evaluation of Performance on Cooling Pad System According to Non-uniform Saturation of in Broiler House
박진선 Park Jinseon , 최락영 Choi Lak-yeong , 이세연 Lee Se-yeon , Favour Daniel Kehinde , 이채린 Lee Chae-rin , 박지연 Park Ji-yeon , 홍세운 Hong Se-woon
Heat stress in broiler houses during the summer can lead to reduced feed intake and feed efficiency, ultimately resulting in decreased productivity. To mitigate heat stress, cooling pads utilizing the evaporative cooling effect have been introduced in commercial broiler houses. In this study, the performance of cooling pads in an actual broiler house was evaluated, and a wind tunnel equipment was designed to precisely analyze their performance. The results revealed that in the broiler house with long cooling pads, the uneven distribution of water led to a decrease in cooling efficiency. Specifically, cooling efficiency was 81% when the cooling pads were wet enough but decreased to 49.6% as the water supply to the cooling pads was not proper. Furthermore, wind tunnel experiments showed that as the airflow speed increased from 0.64 mㆍs-1 to 1.86 mㆍs-1, the temperature reduction decreased from 8.3 ℃ to 6.6 ℃. However, the mass transfer coefficient and heat transfer coefficient increased by 0.0019 mㆍh-1 and 37.32 Wㆍm-2ㆍK-1, respectively, indicating more active evaporation and greater heat removal due to higher airflow speed. Additionally, as relative humidity increased, the temperature reduction significantly decreased. When water was unevenly distributed across the cooling pad, the temperature reduction and cooling efficiency in areas without water were significantly reduced. These findings highlight the importance of maintaining uniform water distribution over the cooling pads to ensure desired cooling effects.
Estimating Agricultural Water Demand Considering the Water Distribution System
In this study, we propose a method for systematically estimating agricultural water demand using the EPA-SWMM model. We utilize watershed and water supply system data to ensure accurate estimations. A comparative analysis was conducted on agricultural water demand over the past ten years, from 2014 to 2023, for the Yongdang, Jangchi, and Geumgye reservoirs. The demand was compared and analyzed among three sources: the design criteria demand calculated using the Hydrological Operation Model for Water Resources System (HOMWRS), the demand calculated with the EPA-SWMM model using irrigation canal network, and the demand outlined in the National Water Management Basic Plan. The average design criteria water demand for the three study areas was found to be approximately 672 mm, while the water demand, taking into account the water supply system, was approximately 1,182 mm. On average, the water demand considering the water supply system was calculated to be 1.76 times the design criteria demand. The demand considering the water supply system was found to be less than the demand presented in the National Water Management Basic Plan but greater than the design criteria demand. The findings of this study can serve as foundational data for addressing the discrepancies between agricultural water demand and supply.
Development of Paddy Grown Soybean Cultivation Area Classification Technology Using DeepLabv3+
안치용 An Chiyong , 강태안 Kang Tae-an , 송철민 Song Chulmin , 박진기 Park Jinki
This study aims to develop a deep learning-based crop classification to effectively assess the cultivation area expansion of paddy-grown soybeans in South Korea. As the cultivation area of paddy fields decreases and the cultivation of soybeans increases, accurately identifying the cultivation area of strategic crops has become crucial. To achieve this, we utilized high-resolution UAV imagery and the DeepLabv3+ deep learning algorithm. DeepLabv3+ can extract information from a wide receptive field, enabling high-accuracy classification and segmentation even in complex agricultural images. The results of this study indicate that the model can predict the cultivation area of soybeans with an accuracy of 94.86%, with a precision of 93.81% and a recall of 93.71%. This research is expected to provide valuable information for agricultural policy and crop management.
Spatio-temporal Distribution Characteristics of Chlorophyll-a and Correlation Analysis with Water Quality Factors in the Namgang Dam Region
This study investigates the relationship between Chl-a concentration and various water quality factors, including temperature, nutrients (TN, TP), TOC, COD, and BOD, in the Namgang Dam region from 2007 to 2023. The correlation analysis between Chl-a and water quality parameters was conducted using the Pearson method, and the cluster analysis of Chl-a was performed using the average linkage method. At Namgang Dam Site 1, Chl-a concentration shows positive correlations with TOC (0.300), TP (0.302), BOD (0.272), and water temperature (0.309). At Site 2, Chl-a shows positive correlations with water temperature (0.273), COD (0.229), TP (0.379), and TOC (0.295). At Site 3, Chl-a concentration has significant positive correlations with COD (0.265), TOC (0.304), TP (0.277), and water temperature (0.302), indicating that these factors play important roles in the growth of phytoplankton. A strong correlation between Chl-a and both TOC and TP, with TP being a major contributor to algal growth, suggesting that phosphorus is a key limiting factor. Conversely, dissolved oxygen (DO) showed a negative correlation, indicating that as algal growth progresses, DO levels decrease, potentially impacting aquatic health negatively. Spatial distribution analysis showed that Chl-a levels were lower upstream and increased significantly downstream, influenced by reduced flow, higher temperatures, and nutrient inflow from agricultural and industrial activities. Dendrogram analysis indicated that certain sites along the Deokcheon and Namgang rivers exhibited similar Chl-a patterns, forming clusters, while the Geungho River site was distinct, suggesting unique water quality characteristics. These findings provide critical insights for predicting and managing algal blooms in the Namgang Dam area, emphasizing the importance of tailored regional water quality management strategies.
