• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.51-67
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• 1996

There are three main rice-growing regions in the United States: the prairie region along the Mississippi River Valley in eastern Arkansas; the Gulf Coast prairie region in southwestern Louisiana and southeastern Texas; and the Central Valley of California. The Central Valley of California is producing about 23% of the US rice(Fig. 1). In California. most of the crop has been produced in the Colusa, Sutter, Butte, Glenn Counties of the Sacramento Valley since 1912, when rice was commercially grown for the first time in the state(Fig. 2). Roughly speaking, the average annual area sown to rice in California is about 300,000 acres to 400,000 acres during the last forty years(Fig. 3). California rice is grown under a Mediterranean climate characterized by warm, dry, clear days, and a long growing season favorable to high photosynthetic rates and high rice yields. The average rice yield per acre is probably higher in California than in any other rice-growing regions of the world(Fig. 4). A dependable supply of irrigation water must be available for a successful rice culture. Most of the irrigation water for California rice comes from the winter rain and snow-fed reservoir of the Sierra Nevada mountain ranges. Less than 10 percent of rice irrigation water is pumped from wells in areas where surface water is not sufficient. It is also essential to have good surface drainage if maximum yields are to be produced. Rice production in California is highly mechanized, requiring only about four hours of labor per acre. Mechanization of rice culture in California includes laser-leveler technology, large tractors, self-propelled combines for harvesting, and aircraft for seeding, pest control, and some fertilization. The principal varieties grown in California are medium-grain japonica types with origins from the cooler rice climates of the northern latitudes (Table 1). Long-grain varieties grown in the American South are not well adapted to California's cooler environment. Nearly all the rice grown recently in California are improved into semidwarf varieties. Choice of variety depends on environment, planting date, quality desired, marketing, and harvesting scheduling. The Rice Experiment Station at Biggs is owned, financed, and administered by the rice industry. The station was established in 1912, as a direct result of the foresight and effort of Charles Edward Chambliss of the United States Department of Agriculture. Now, The station's major effort is the development of improved rice varieties for California.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.4
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• pp.1-7
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• 2020

This study quantified annual uptake and storage of carbon by urban greenspace in institutional lands and suggested improvement of greenspace structures to enhance carbon reduction effects. The study selected a total of five study cities including Seoul, Daejeon, Daegu, Chuncheon, and Suncheon, based on areal size and nationwide distribution. Horizontal and vertical greenspace structures were field-surveyed, after institutional greenspace lots were selected using a systematic random sampling method on aerial photographs of the study cities. Annual uptake and storage of carbon by woody plants were computed applying quantitative models of each species developed for urban landscape trees and shrubs. Tree density and stem diameter (at breast height) in institutional lands averaged 1.4±0.1 trees/100 ㎡ and 14.9±0.2 cm across the study cities, respectively. Of the total planted area, the ratio of single-layered planting only with trees, shrubs, or grass was higher than that of multi-layered structures. Annual uptake and storage of carbon per unit area by woody plants averaged 0.65±0.04 t/ha/yr and 7.37±0.47 t/ha, which were lower than those for other greenspace types at home and abroad. This lower carbon reduction was attributed to lower density and smaller size of trees planted in institutional lands studied. Nevertheless, the greenspace in institutional lands annually offset carbon emissions from institutional electricity use by 0.6 (Seoul)~1.9% (Chuncheon). Tree planting in potential planting spaces was estimated to sequester additionally about 18% of the existing annual carbon uptake. Enhancing carbon reduction effects requires active tree planting in the potential spaces, multi-layered/clustered planting composed of the upper trees, middle trees and lower shrubs, planting of tree species with greater carbon uptake capacity, and avoidance of the topiary tree maintenance. This study was focused on finding out greenspace structures and carbon offset levels in institutional lands on which little had been known.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.1
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• pp.120-128
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• 2018

The purpose of this study is to establish basic data for the continuous protection management policy of domestic natural world heritage and mixed world heritage, and to examine the present situation and characteristics of the protection management according to the World Heritage Convention on the World Heritage listed Huangshan. The results of this study are as follows. First, Huangshan began to be protected by the establishment of the Huangshan Construction Committee in 1933, and after the designation of national park in 1982, laws and regulations were established in the central ministries, And various projects related to utilization have been implemented. Secondly, the establishment of the boundary for protection was actively intervened by the central government, such as the reorganization of the boundary of Huangshan through the administrative district plan. In order to protect the ecological and landscape value as well as the cultural factor, And designated a heritage designated area. Third, the protection management of Huangshan was divided into four major stages. The first phase was divided into the period when administrative measures were taken to manage the protection of Huangshan. The second phase was designated as a national park in Huangshan. The third period was the time of the protection-oriented project according to the recommendation of the international organizations after the World Heritage listed. The fourth period was the expansion of the tourism industry for the continuous use of protection of Huangshan city, My preservation business was being implemented. Fourth, Huangshan is managed by the central government and the city government. Huangshan, which is a mixed heritage, is managed jointly by the Ministry of Cultural Heritage Administration and the Ministry of Natural Heritage Administration. The protection and management of Huangshan promoted the efficiency and expertise of the heritage-related work through the establishment of the administrative unit-specific management system, and the local governments were entrusted with the authority to implement the protection management policies that meet local characteristics. Fifth, the preservation area of Huangshan has been destroyed by the development policy centered on the mountain. In addition, according to the operation of accommodation facilities, there are problems such as sewage, garbage disposal, and environmental pollution caused by tourists, and the damage caused by pests and diseases in planted plantations around the area and changes in ecosystem due to the composition of cable cars. Sixth, for the continuous protection of Huangshan, strict regulations on new construction, extension and management of accommodation are required, and it is necessary to install facilities to limit and control the number of visitors.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.238-246
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• 2018

Purpose: The purpose of this study is to examine the directions for establishing a disaster safety village in rural areas where damage from a similar type of disaster occurs repeatedly by conducting the consciousness survey targeting at experts and disaster safety officials in a local government. Method: The risks of disaster in rural areas were examined and the concept and characteristics of disaster safety village which is a measure on the basis of Myeon (township) among the measures of village unit were examined in order to carry out this study. In addition, opinion polling targeting at officials-in-charge in the local government and survey targeting at experts in disaster safety and building village were conducted. Based on the findings, the directions for establishing a disaster safety village that fitted the characteristics of rural areas were examined. Result: The officials-in-charge in the local government answered that rural areas have a high risk of storm and flood such as heavy snowing, typhoon, drought, and heavy rain as well as forest fire, and it is difficult to draw voluntary participation of farmers for disaster management activities due to their main duties. They also replied that active support and participation of residents in rural areas are necessary for future improvement measures. The experts mostly replied that the problem of disaster safety village project is a temporary project which has low sustainability, and the lack of connections between the central government, local governments and residents was stressed out as the difficulties. They said that measures to secure the budget and the directions of project promotion system should be promoted by the central government, local governments and residents together. Conclusion: The results of this study are as follows. First, a disaster safety village should be established in consideration of the disaster types and characteristics. Second, measures to secure the budget for utilizing the central government fund as well as local government fund and village development fund should be prepared when establishing and operating a disaster safety village in rural areas. Third, measures to utilize a disaster safety village in rural areas for a long period of time such as the re-authorization system should be prepared in order to continuously operate and manage such villages after its establishment. Fourth, detailed measures that allow residents of rural areas to positively participate in the activities for establishing a disaster safety village in rural areas should be prepared.

• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1339-1348
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• 2021

In accordance with the River Law, the basic river maintenance plan is established every 5-10 years with a considerable national budget for domestic rivers, and various river surveys such as the river section required for HEC-RAS simulation for flood level calculation are being conducted. However, river survey data are provided only in the form of a pdf report to the River Management Geographic Information System (RIMGIS), and the original data are distributedly owned by designers who performed the river maintenance plan in CAD format. It is a situation that the usability for other purposes is considerably lowered. In addition, when using surveyed CAD-type cross-sectional data for HEC-RAS, tools such as 'Dream' are used, but the reality is that time and cost are almost as close as manual work. In this study, RAUT (River Information Auto Upload Tool), a tool that can solve these problems, was developed. First, the RAUT tool attempted to automate the complicated steps of manually inputting CAD survey data and simulating the input data of the HEC-RAS one-dimensional model used in establishing the basic river plan in practice. Second, it is possible to directly read CAD survey data, which is river spatial information, and automatically upload it to the river spatial information DB based on the standard data model (ArcRiver), enabling the management of river survey data in the river maintenance plan at the national level. In other words, if RIMGIS uses a tool such as RAUT, it will be able to systematically manage national river survey data such as river section. The developed RAUT reads the river spatial information CAD data of the river maintenance master plan targeting the Jeju-do agar basin, builds it into a mySQL-based spatial DB, and automatically generates topographic data for HEC-RAS one-dimensional simulation from the built DB. A pilot process was implemented.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.175-186
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• 2019

Efforts have been made to introduce the climate smart agriculture (CSA) for adaptation to future climate conditions, which would require collection and management of site specific meteorological data. The objectives of this study were to identify requirements for construction of agricultural meteorology information service system (AMISS) using technologies that lead to the fourth industrial revolution, e.g., internet of things (IoT), artificial intelligence, and cloud computing. The IoT sensors that require low cost and low operating current would be useful to organize wireless sensor network (WSN) for collection and analysis of weather measurement data, which would help assessment of productivity for an agricultural ecosystem. It would be recommended to extend the spatial extent of the WSN to a rural community, which would benefit a greater number of farms. It is preferred to create the big data for agricultural meteorology in order to produce and evaluate the site specific data in rural areas. The digital climate map can be improved using artificial intelligence such as deep neural networks. Furthermore, cloud computing and fog computing would help reduce costs and enhance the user experience of the AMISS. In addition, it would be advantageous to combine environmental data and farm management data, e.g., price data for the produce of interest. It would also be needed to develop a mobile application whose user interface could meet the needs of stakeholders. These fourth industrial revolution technologies would facilitate the development of the AMISS and wide application of the CSA.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.312-326
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• 2020

Generation of weather forecasts at 100 m resolution through a statistical downscaling process was implemented by Korea Meteorological Administration Post- Processing (KMAPP) system. The KMAPP data started to be used in various industries such as hydrologic, agricultural, and renewable energy, sports, etc. Cheorwon area and Jeonbuk area have horizontal planes in a relatively wide range in Korea, where there are many complex mountainous areas. Cheorwon, which has a large number of in-situ and remotely sensed phenological data over large-scale rice paddy cultivation areas, is considered as an appropriate area for verifying KMAPP prediction performance in agricultural areas. In this study, the performance of predicting KMAPP temperature changes according to ecological changes in agricultural areas in Cheorwon was compared and verified using KMA and National Center for AgroMeteorology (NCAM) observations. Also, during the heat wave in Jeonbuk Province, solar radiation forecast was verified using Automated Synoptic Observing System (ASOS) data to review the usefulness of KMAPP forecast data as input data for application models such as livestock heat stress models. Although there is a limit to the need for more cases to be collected and selected, the improvement in post-harvest temperature forecasting performance in agricultural areas over ordinary residential areas has led to indirect guesses of the biophysical and phenological effects on forecasting accuracy. In the case of solar radiation prediction, it is expected that KMAPP data will be used in the application model as detailed regional forecast data, as it tends to be consistent with observed values, although errors are inevitable due to human activity in agricultural land and data unit conversion.

• Journal of Korea Water Resources Association
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• v.55 no.6
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• pp.437-446
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• 2022

In April 2020, the Korean government decided to operate the Hwacheon reservoir, a hydropower reservoir to supply water, and it is currently under pilot operation. Through the pilot operation, the Hwacheon reservoir is the first among the hydropower reservoirs in Korea to make a constant release for downstream water supply. In this study, the water supply capacity of the Hwacheon reservoir was estimated using the inflow data of the Hwacheon reservoir. A simulation model was developed to calculate the water supply that satisfies both the monthly water supply reliability of 95% and the annual water supply reliability of 95%. An optimization model was also developed to evaluate the water supply capacity of the Hwacheon reservoir. The inflow data used as input data for the model was modified in two ways in consideration of the impact of the Imnam reservoir. Calculating the water supply for the Hwacheon reservoir using the two modified inflows is as follows. The water supply that satisfies 95% of the monthly water supply reliability is 26.9 m³/sec and 24.1 m³/sec. And the water supply that satisfies 95% of the annual water supply reliability is 23.9 m³/sec and 22.2 m³/sec. Hwacheon reservoir has a maximum annual water supply of 777 MCM (Million Cubic Meter) without failure in the water supply. The Hwacheon reservoir can supply 704 MCM of water per year, considering the past monthly power generation and discharge patterns. If the Hwacheon reservoir performs a routine operation utilizing its water supply capacity, it can contribute to stabilizing the water supply during dry seasons in the Han River Basin.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.99-112
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• 2021

This study was performed to predict spatial change of future forestland area in South Korea at regional level for supporting forest-related plans established by local governments. In the study, land use was classified to three types which are forestland, agricultural land, and urban and other lands. A logistic regression model was developed using transitional interaction between each land use type and topographical factors, land use restriction factors, socioeconomic indices, and development infrastructures. In this model, change probability from a target land use type to other land use types was estimated using raster dataset(30m×30m) for each variable. With priority order map based on the probability of land use change, the total annual amount of land use change was allocated to the cells in the order of the highest transition potential for the spatial analysis. In results, it was found that slope degree and slope standard value by the local government were the main factors affecting the probability of change from forestland to urban and other land. Also, forestland was more likely to change to urban and other land in the conditions of a more gentle slope, lower slope criterion allowed to developed, and higher land price and population density. Consequently, it was predicted that forestland area would decrease by 2027 due to the change from forestland to urban and others, especially in metropolitan and major cities, and that forestland area would increase between 2028 and 2050 in the most local provincial cities except Seoul, Gyeonggi-do, and Jeju Island due to locality extinction with decline in population. Thus, local government is required to set an adequate forestland use criterion for balanced development, reasonable use and conservation, and to establish the regional forest strategies and policies considering the future land use change trends.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.196-209
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• 2022

This study compared and analyzed the spatial division function and role of partitions by comparing the entire space and the spatial changes before and after the installation of partitions in <Donggwoldo>, which was manufactured in the late Joseon Dynasty. As a research method, a set standard was prepared to decompose the space of <Donggwoldo> into a unit space, and the standard was set according to the role and height of the space by classifying it into a main space, sub space, and transition space. Two convex maps were prepared according to before and after the installation of the Panjang, and the values of connectivity, control, and integration, which are spatial syntax variables, were calculated and analyzed. The results of the study are as follows. First, the partition in <Donggwoldo(東闕圖)> did not affect the overall spatial arrangement and control or connection of Donggwol, but the movement and access of space is limited to specific areas. Second, the partition was a facility intensively distributed in Naejeon(內殿) and Donggung(東宮) to be used actively in the way of space utilization. It shows that the unit space increased rapidly due to the installation of the partition. Since the partition was installed in the spaces that were open and under high control in the case of Naejeon(內殿), it helped to secure private spaces as closed ones under low control. On the other hand, for Donggung(東宮), the spaces were compartmented and divided with the partition to guide the movement path through narrow gates of the partition and increase the depth of the space. This helped to create spaces that are free and can be hidden as it increased the number of spaces coming through. Third, In addition to the functions of "eye blocking, space division, and movement path control" revealed in prior research, the partition has created a "space that is easy to control" within a specific area. The installation of the partition reduced the scale through the separation of spaces, but it occurred the expansion of the movement path and space. Also, the partition functioned to strengthen hiding and closure or increase openness as well through space division. This study is significant in that it revealed the value of the spatial control function of panjang through the analysis of spatial control and depth by analyzing the function of the partition with a mathematical model in addition to the analysis and study of the function and role of panjang. In addition, it is valuable in that it has prepared a framework for analysis tools that can be applied to traditional residential complexes similar to palaces by applying space syntax to <Donggungdo> to create convex spaces according to unit space division and connection types of palace architecture and landscape elements.