This study aims to analysis environmental problems by deforesation using Remote Sensing and GIS techniques for selected study areas in North Korea.
The results of the research on landuse change of cropland and forest are following:
Cropland ratio ...
This study aims to analysis environmental problems by deforesation using Remote Sensing and GIS techniques for selected study areas in North Korea.
The results of the research on landuse change of cropland and forest are following:
Cropland ratio of Whanghaenam-Do was 16% in comparison with mountain area. Elevation of cropland was 80-750m in average, slope was 7-15°. elevation of these area was 314m, slope was 19°. this results analyzed higher 112m, 10° each height and slope of cropland. elevation and slope of cropland compared distance in relation with human geography. Agricultural land was separated from 20km, mountains 37km of distance from cities, each distributed 2.8km, 4.5km from roads. 20km cropland buferring of average circle was higher in Sungseon, Onseong, NajinSeonbong, Cheongjin, Eolang, Hamheung, Dancheon, Sinpo, Jaseong, Hesan, Manpo, Jagang.
The Anju Plain can be divided into alluvial plains, coastal plains and erosional plains, and the Hamheung Plain can be regarded as alluvial plains by Seongcheon-river. Approximately 84.98㎢ tidal flats have been reclaimed to farmlands and saltpans, and the most channels of medium and small rivers have been straightened at the Anju Plain during the last one hundred years. At the Hamheung Plain, on the other hands, approximately 3.40㎢ land has been increased by the advances of coastal line of the Seongcheon-river delta with a maximum of 800m, and channels of SeoSeongcheon-river which showed anastomosing channels have been disappeared by reclamation. Gwang-po has been decreased by artificial reclamations and river sedimentary processes.
Comparatively North Korea areas are more eroded three times as much as South Korea part using RUSLE model in Imjin River basin located on DMZ of Central Korea. Because of cropland development such as corn field in the hillslope, in North Korea, more surface soil erosion and transportation to the river bed give rise to fregment flood hazards.
Food situation of the North Korea was relatively good in 1970's, but, 1990's was the worst in the way. Western areas possessing more plains were more higher than mountainous areas of the northern and eastern parts of North Korea. Growth ratio of food production and population have grown very steadily until 1990's, but the increase ratio of population exceeded food productivity after 1990's. Cropland reclamation for improving these situation have caused deforestation and environmental problems and especially eastern and northern area became more serious.
This paper deals with the environmental change by landuse in Duman River basin, Northeast Korea. Landforms of Duman River basin include lava plateau(Baekdusan) and deeply incised valley. Image analysis present that surface soil erosion has become serious because of cropland development and deforestatin on the hillslope, water quality of the Duman River became degraded by thhe development and mining in Musan Iron mine and other coal mines. So, much suspended materials are included to the river and the turbidity of the river are increasing.
Using Z index as classification of drought-flood intensity and based on the precipitation data in Huishan in the past 50 years, the frequencies of years and four seasons of flood drought have been analyzed and their change features have also been studied based on tendency analysis and MESA and wavelet ways. Results show that the frequencies of flood-drought of years and four seasons exceed 24% in Huishan and flood-drought disasters are high frequency.
Results show that from 1917 to 2006, area of crop land , plantation, building site, unused land increased and natural forest, grassland, water area, wetland decreased, in Musan region and Hoeryong region. But the area of natural forest is acute reduced by 7925.34hm2,and the amplitude of building site is increased rapidly in Musan region.