• 한국토양비료학회지
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• 제42권Spc호
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• pp.45-46
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• 2009

간척지 토양은 도시화와 산업화로 인해 잠식되는 농경지를 대체하는 식량공급원으로 간척지는 쌀 산업 외에 원예, 축산 등 다양한 생물산업 기반으로 활용되고 있다. 그리고 간척지 논농업(간척지 논 307만 ha)은 온실가스 저감 기능을 가지고 있으며 년간 논 1ha당 이산화탄소 흡수량 21.9t, 산소 공급량 15.9t으로 알려져 있다. 그러나 높은 염농도와 지하수위, 지하수 상승에 의한 재염화 현상, 토양 물리화학성과 배수 불량, 논의 경우 적정 유효토심은 50cm 정도이나 간척지 논 유효토심 20cm 이하로 유효토심이 매우 낮은 편이다. 또한 간척년대 경과할수록 제염은 되나 토양물리성 불량, 시비량 과다와 양분 불균형 발생으로 인하여 수분과 양분보유능 향상 토양관리 기술 개발 필요하다.

• 한국농공학회지
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• 제18권4호
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• pp.4265-4273
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• 1976

1. Fine aggregates of concrete are very important for the construction works and construction cost determination. Most of fine aggregates are from the river sand, but the amount of storage in the river side is steadily decreasing due to continuous construction works. Therefore, another source of fine aggregates is needed to meet increasied demand of sand. 2. Beach sand is a possible source of fine aggregates. But rust of steel bar is caused by CL-chemical of beach sand. Therefore, desalinization of beach sand is requested to get durable reinforced concrete. Economical methods of desalinization are as follows. (a) Flooding and drainage method. (b) Washing of beach sand with water supply and mixing. (c) Spreading of beach sand on the land and leaching by rain water for a few month. 3. Hardening of concrete with beach sand is accelerated due to salt, Thus early stage strength increase leads to make cracks. Also later stage strength decreases and durability becomes worse. By using appropriate admixture, the quality of concrete can be improved.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제1호
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• pp.59-66
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• 2001

The tremendous growth of population and physical development in the largest urban agglomeration in Indonesia -the Jakarta Metropolitan Region, also known as Jabotabek (Jakarta, Bogor, Tanggerang, Bekasi)- has created many environmental problems, such as land use conversion, increasing urban temperature, water and air pollution, intrusion of seawater, and flooding. These problems have become more serious as the urban green space (trees, shrubs, and groundcovers) has decreased rapidly with the urbanization process. Urban green space directly benefits the urban environment through ameliorating air pollution, controlling temperature, contributing to the balance of the hydrological system, and providing space for recreation and relaxation. Because there is little hard data to support the claim of decreasing greenery in Jabotabek, it is necessary to measure the amount of urban green space. The paper describes the spatial analysis of urban green space within Jabotabek through the use of a geographical information system (GIS). We used GIS and remote sensing to determine land cover change and predicted greenery percentage. Interpretation of Landsat data for 1972, 1983, 1990, and 1997 showed that Jabotabek has experiences rapid development and associated depletion of green open space. The proportion of green open space fell by 23% from 1972 to 1997. We found a low percentage of urban green space in the center of Jakarta but a high percentage in fringe area. The amount of greenery is predicted by the Ratio Vegetation Index (RVI) model: predicted greenery (%) = [146.04] RVI - 134.96. We consider that our result will be useful for landscape planning to improve the environment of Jabotabek.

• 한국수자원학회논문집
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• 제32권4호
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• pp.501-510
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• 1999

북한강 수계의 농업소유역에 대하여 하천수(2년)와 지하수(1년) 수질을 모니터링하여 분석하였다. 농업소유역의 주요한 비점원 오염물질인 총질소, 질산성 질소, 총인, BOD, TSS 및 대장균 농도를 주기적으로 측정하였다. 계절에 따른 수질의 변화 및 지하수와 하천수 수질과의 관계 비교를 통하여 토지이용이 수질에 미치는 영향을 분석하였다. 연구유역의 지하수 수위와 총질소, 질산성 질소의 농도의 벼농사와 밀접한 관련이 있었고 지하수와 하천수의 질소농도의 변화도 밀접한 관련이 있음이 나타나 벼농사가 하천의 질소농도에 많은영향을 주는 것으로 나타났다. 그러나 토지이용(벼농사)과 지하수 및 하천수의 총인, BOD, 대장균 농도 사이에는 일정한 관계를 발견할 수 없었다. 본 연구결과는 농업소유역의 수질변화를 이해하고 소하천의 수질관리정책을 개발하는데 유용하게 활용될 수 있을 것이다.

• 한국농공학회논문집
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• 제56권5호
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• pp.67-75
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• 2014

In this study, the large-scale hydraulic model test was performed to investigate the hydraulic characteristics for development of the non-power soil cleaning and keeping system at the dike gate. The outlet height, outflow number, outflow discharge, and outflow cycle were compared and analyzed. The non-power soil cleaning and keeping system was most effective at 11.2 mm in the outlet height. And then the mean outflow cycle was 1.09 sec, and the mean outflow discharge was $0.00164m^3/s$. The total outflow number increased gradually as the water level of a water tank increased, and the outlet height decreased. As a level of water tank decreased, the mean outflow cycle was lengthened, and the unit outflow discharge increased. This result showed this system was most effective. To remove the silty clay deposited in facilities, the methods of excavation, dredging, high pressure washing, etc have been applied to the tidal facilities such as land reclamation, a small size fishing port, and a harbor for maintenance. However, this is extremely cost-ineffective, whereas the non-power soil cleaning and keeping system will bring about an enormously positive economic effect. In addition, when the non-power soil cleaning and keeping system is applied to the dike gate of land reclamation, a thorough examination of the local tidal data and the careful system planning are required to prevent the disaster damage caused by flooding.

• 한국토양비료학회지
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• 제40권2호
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• pp.118-130
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• 2007

태풍 루사시 집중호우로 인하여 농경지에 대한 피해가 극심했던 강원도 강릉지역의 강우특성과 침식, 매몰, 침수, 산불지역에 대한 피해양상을 조사하였으며, 복원대책을 요학한 결과는 다음과 같다. 1. 태풍루사에 의해 870 mm가 내린 강릉지역의 집중호우 확률강우 재현기간은 345년으로 분석되었다. 2. 토양침식지점과 인근지점 토양의 형태적 특성을 비교한 결과, 토양침식지점이 유효토심이 낮고, 경사장은 길고, 경사도는 높았으며, 주로 오목지형에서 토양침식에 많이 발생하였다. 3. 산불지역에서 경사가 심할수록, 지면피복도가 감소할수록 토양침식 등급이 높았는데, 저구릉에서 산악지로 갈수록, 미세지형은 볼록한 형태에서 직선형일수록 토양침식 등급이 높았다. 토양침식을 받은 지역은 혼효림 식재, Weeping love grass 등의 식재를 하고 가능한 한 단기간에 피복도를 증대시켜 2차 피해를 예방해야 할 것으로 판단된다. 4. 대부분의 농경지는 피해 후 복원이 잘 되어있으나, 일부농경지는 매몰된 모래층을 완전히 제거하지 않았기 때문에 토양의 비옥도 저하로 작물생육이 부진하였으며, 토성 급변층으로 인하여 심토에 배수 불량층이 생성되었다. 매몰된 토양을 완전히 제거하여 우량 객토원으로 객토하고 토양검정에 의한 작물별 시비처방이 필요한 것으로 판단되었다.

• 한국농공학회논문집
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• 제65권6호
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• pp.65-78
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• 2023

In recent times, the frequency and intensity of natural disasters, such as heavy rains and typhoons, have been increasing due to the impacts of climate change. This has led to a rise in social and economic damages. Rural areas, in particular, possess limited disaster response capabilities due to their underdeveloped infrastructure and are highly vulnerable to flooding. Therefore, it is crucial to establish preventative and responsive measures. In this study, an Inventory-Based Flood Loss Estimation (IB-FLE) method utilizing high-resolution spatial information was developed for estimating flood-related losses in rural areas. Additionally, the developed approach was applied to a study area and compared with the Multidimensional Flood Damage Analysis (MD-FDA) method. Compared to the MD-FDA, the IB-FLE enables faster and more accurate estimation of flood damages and allows for the assessment of individual building and agricultural land losses using up-to-date information. The findings of this study are expected to contribute to the rational allocation of budgets for rural flood damage prevention and recovery, as well as enhancing disaster response capabilities.

• 대한원격탐사학회지
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• 제16권4호
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• pp.327-338
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• 2000

The forest conditions of North Korea has been a great concern since it was known to be closely related to many environmental problems of the disastrous flooding, soil erosion, and food shortage. To assess the long-term changes of forest area as well as the canopy conditions, several sources of multitemporal satellite data were applied to the study area near Kaesung. KOMPSAT-1 EOC data were overlaid with 1981 topographic map showing the boundaries of forest to assess the deforestation area. Delineation of the cleared forest was performed by both visual interpretation and unsupervised classification. For analyzing the change of forest canopy condition, multiple scenes of Landsat and SPOT data were selected. After preprocessing of the multitemporal satellite data, such as image registration and normalization, the normalized difference vegetation index (NDVI) was derived as a representation of forest canopy conditions. Although the panchromatic EOC data had radiometric limitation to classify diverse cover types, they can be effectively used t detect and delineate the deforested area. The results showed that a large portion of forest land has been cleared for the urban and agricultural uses during the last twenty years. It was also found that the canopy condition of remaining forests has not been improved for the last twenty years. It was also found that the canopy condition of remaining forests has not been improved for the last twenty years. Possible causes of the deforestation and the temporal pattern of canopy conditions are discussed.

• 한국환경과학회지
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• 제14권9호
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• pp.817-825
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• 2005

The purpose of this study was to research about salt marsh flora and vegetation in the Dongjin-river estuary area where has a project for Sea Man Geum Reclaimed Land so that we can foster foundation on restoration of an ecological habitat, development of applicable plant and establishment of a conservation policy after deceloping the reclaimed land for salt marsh vegetation which has great value ecologically. In conclusion, we was distributed that there are 7 families 21 genera, 25 species, 2 varieties of vascular plant at the Dongjin-river estuary area which have 27 taxa in total and are $0.64\%$ among 4,191 of korean vascular plant. There are also 2 family, 2 genus, 2 species of a naturalized plant which are $1.1\%$ of indicator of a naturalized plant salt marsh vegetation of the downstream are very much affected by the time of inundation, tidal water so that a low degree of salt marsh has frequent flooding by sea water and has a pure group of Suaeda japonica. A Phragmites communis, Carex scabrifolia are distributed mainly around a waterway of salt marsh and Zoysia sinica, Atriplex subcordata, Phragmites communis are living in stock as forming into patch around medium salt marsh. Suaeda asparagoides, Phacelurus latifolius are living around a little high ground and a Phragmites communis is a behind vegetation of Phacelurus latifolius and a part of the Phragmites communis are living along with waterway in a salt marsh as a community. By the 2-M method twelve plant communities were recognized ; Suaeda japonica. Carex scabrifolia, Zoysia sinica, Artemisia scoparia, Phacelurus latifolius, Phragmites communis, Suaeda maritima, Suaeda japonica-Atriplex gmelini, Phragmites communis-Suaeda japonica, Suaeda japonica-Salicornia herbacea, Salicornia herbacea-Suaeda aspar-agoides and Scirpus planiculmis community. The actual vegetation map was constructed on the grounds of the communities classified and other data.

• 한국환경복원기술학회지
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• 제25권6호
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• pp.51-64
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• 2022

Along with the urbanization, the risk of urban flooding due to climate change is increasing. Flood regulation, one of the ecosystem services, is implemented in the different level of function of flood risk mitigation by the type of ecosystem such as forests, arable land, wetlands etc. Land use changes due to development pressures have become an important factor in increasing the vulnerability by flash flood. This study has conducted evaluating the urban flood regulation service using InVEST UFRM(Urban Flood Risk Model). As a result of the simulation, the potential water retention by ecosystem type in the event of a flash flood according to RCP 4.5(10 year frequency) scenario was 1,569,611 tons in urbanized/dried areas, 907,706 tons in agricultural areas, 1,496,105 tons in forested areas, 831,705 tons in grasslands, 1,021,742 tons in wetlands, and 206,709 tons in bare areas, the water bodies was estimated to be 38,087 tons. In the case of more severe 100-year rainfall, 1,808,376 tons in urbanized/dried areas, 1,172,505 tons in agricultural areas, 2,076,019 tons in forests, 1,021,742 tons in grasslands, 47,603 tons in wetlands, 238,363 tons in bare lands, and 52,985 tons in water bodies. The potential economic damage from flood runoff(100 years frequency) is 122,512,524 thousand won in residential areas, 512,382,410 thousand won in commercial areas, 50,414,646 thousand won in industrial areas, 2,927,508 thousand won in Infrastructure(road), 8,907 thousand won in agriculture, Total of assuming a runoff of 50 mm(100 year frequency) was estimated at 688,245,997 thousand won. In a conclusion. these results provided an overview of ecosystem functions and services in terms of flood control, and indirectly demonstrated the possibility of using the model as a tool for policy decision-making. Nevertheless, in future research, related issues such as application of models according to various spatial scales, verification of difference in result values due to differences in spatial resolution, improvement of CN(Curved Number) suitable for the research site conditions based on actual data, and development of flood damage factors suitable for domestic condition for the calculation of economic loss.