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Oceanography / Meteorology
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Investigation on Tidal Land Reclamation in Korea Using Satellite Image Data
Kiyoshi Toril1, Takashi Hoshi2, Takashi Kano3, Byung Jin Cho4,
Byung Ho Lim5, and Moon Soo Choi2
1Dev. Of Environmental Sci. & Tech. Graduate School of Agriculture,
Kyoto Univ., Kitashirakawa, Sakyo, Kyoto, JAPAN
TEL & FAX In'l-81(0)75-753-6459,
E-mail toril@kais.kyoto-u.ac.jp
2Dept. Of Inform. Sci. Ibaraki Univ., Nakanarusaza-cho, Hitachi, JAPAN
3Tokyo Univ.of Fisheries, Konan, Minato-ku Tokyo, JAPNA
TEL. Int'l-81(03)-5463-073,
E-Mail kanotaka@tokyo-u-fish.ac.jp
4Det. Of Agric Eng., Gyensang nat. Uiv. Chinju, Korea
Tel. In'l-82-591-751-5433,
E Mail bjcho@gshp.gsnu.ac.kr
5Saemankeum Project office, Rural Development Corporation. Iri, Korea
Abstract
In the west coast of Korean Penisula, facing the Yellow Sea, there exists a wide range of tidal differences between the low and high tides. As a result, the vast tracts of shallow tidal flats appears along the coastal lines during low tides. Such scale and compreshevsive tidal land reclamation projects have been underway since 1980s. It will take about fifteen more years to complete the project. In addition to the wide ranges of tidal differences and shallow fertile tidal flats exposed during the low tide, the given construction advantages such as plenty of construction materials nearby, scattered small island, Rias type coast lines and proper water resources have played important roles to boost such kinds of reclamation works. The purpose of the present study is to monitor, using satellite imagery, the sequence of changes that will occur including the land use and environment in the area with the progress of reclamation work. We focused on the two large scale projects, Yongsangang and Saemankeum. Using satellite image data, such as MOS-1, SPOT, Landsat TM, and JERS, we have been investigating how these projects are being developed and implemented. Some results of our preliminary investigation are discussed in this paper.
Introduction
In Korea, agricultural development meant construction of small-scale reservoirs, construction of pumping system providing irrigation water relatively easily and construction of intake weirs unil 1960. However, after such small-scale development had been implemented, supply of irrigation water to rainfed paddies in hilly lands, improvement of drainage in wet lowlands, farm land expansion by land reclamation have become the main projects of agricultural development. To carry out such a project, extremely advanced agricultural knowledge and engineering techniques are needed. In Korea, 72% of paddies have irrgation facilities. Agricultural development policy is also shifting from simple, small-scale agricultural development and land improvement to large-scale integrated regional development and land improvement to large-scale integated regional development work. For example, 12 projects have been conducted from 1970 to 1990. The total area of the projects has extended over 109,869 ha.
Newly reclamated farm land was 8567 ha and the mean project area was 9.156 ha. From 1990, 3 large-scale projects have been completed and their total area was 53,100 ha, which included 10,237 ha of newly developed farm land. The mean area of the 3 projects 17,00 ha, which is about twice he scale in the years before 1990.
Here, yangesangan integrated agricultural development project which is the largest project in the past and the gigantic project Saemankeum which was started several years ago are focused. This district was studied 3 years ago10 and ground truth was performed again this year. The projects in both areas were put into practice after careful examination and the and it may be dfficult to obtain new finding from satellite image data. However, by accumulating image data in time series.
1. Outlines of Yangsangan comprehensive agricultural development project
Yangasangan project is an integrated project for agricultural development and was started in 1972. The whole development process has been put into practice by upper into 5 districts. The integrated agricultural development in the first district, the upper stream of Yangsangan river, has been completed. The second district is the integrated agricultural development in the Yangasangan river mouth, which is in the final stage now. The third district is the enclosure of two gulfs, yangan Ho and Keum Ho and their desalination and water area reclamation and enclosure of the gulfs has been completed. Since Mogpo Estuary dam and the link canal of yangan ho lake have been completed, desalination of yangan Ho lake is progressing by introducing fresh water from Yangasangan rive to Yandgun Ho lake but the link canal to Keum Ho has not been completed. Construction of polder dikes, farm lands, irrigation canals and drainages system in the third district have not been started yet.
Outlines of these projects are as follows: construction of the enclosure dike of 4.35 km in length in the Yangasangan river mouth of the second district resulted in completion of Mogpo estuary dam, a desalted reservoir with a capacity of 253.3 million m3 and 6.872 ha of reclamation land. At the same time, land consolidation was implemented as well as the irrigation system with stable water resources and the agricultural basis of 4,899 ha was improved. This second district is near the end taking 16 years from 1976 to 1993. As a result, production of paddy rice and barley ahs improved enormously and the inland traffic net has been provided by utilizing the enclosure dike as a road. It has become possible to use 47 million m3 of water annually for industrial and urban uses.
In the adjacent third district, reclamation of tidal flat is in progress while desalting by closing yangan Ho and Keum Ho and introducing excess water in Mogpo Esuary dam in the second district by a direct link canal. The works in this district were started in 1987. The length of the enclosure dike for yangan Ho is 2.2 km while the water resources ha and the area of the agricultural land adjacent to the water area reclamation offered for improvement of irrigation and land consolidationis 6,730 ha.
The length of the enclosure dike for Keum Ho is 2.1 km and the water resources to be developed is 75 million m3, area of water land reclamation is 3,770 ha, and the area offered for improvement of irrigation and land consolidation in the adjacent agricultural lands is 3.030 ha. The enclosure dike is utilized as a road connection to the other side of the river, and is very useful in improving raffic situation in the districts in the tip of the peninula, the places which had been the isolation island with the land in old days peninsula, the places which been the isolated islands within the land in the old days.
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