• Journal of Ecology and Environment
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• v.41 no.11
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• pp.302-309
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• 2017

Background: Large-scale land-use change is being caused by various socioeconomic problems. Land-use change is necessarily accompanied by changes in the regional carbon balance in terrestrial ecosystems and affects climate change. Therefore, it is crucial to understand the correlation between environmental factors altered by land-use change and the carbon balance. To address this issue, we studied the characteristics of soil carbon flux and soil moisture content related to rainfall events in mountain pastures converted from deciduous forest in Korea. Results: The average soil moisture contents (SMC) during the study period were 23.1% in the soil respiration (SR) plot and 25.2% in the heterotrophic respiration (HR) plot. The average SMC was increased to 2.1 and 1.1% in the SR and HR plots after rainfall events, respectively. In addition, saturated water content was 29.36% in this grassland. The soil water content was saturated under the consistent rainfall of more than $5mm\;h^{-1}$ rather than short-term heavy rainfall event. The average SR was increased to 28.4% after a rainfall event, but the average HR was decreased to 70. 1%. The correlation between soil carbon flux rates and rainfall was lower than other environmental factors. The correlation between SMC and soil carbon flux rates was low. However, HR exhibited a tendency to be decreased when SMC was 24.5%. In addition, the correlation between soil temperature and respiration rate was significant. Conclusions: In a mountain pasture ecosystem, rainfall induced the important change of soil moisture content related to respiration in soil. SR and HR were very sensitive to change of SMC in soil surface layer about 0-10-cm depth. SR was increased by elevation of SMC due to a rainfall event, and the result was assumed from maintaining moderate soil moisture content for respiration in microorganism and plant root. However, HR was decreased in long-time saturated condition of soil moisture content. Root has obviously contributed to high respiration in heavy rainfall, but it was affected to quick depression in respiration under low rainfall. The difference of SMC due to rainfall event was causative of a highly fluctuated soil respiration rate in the same soil temperature condition. Therefore, rainfall factor or SMC are to be considered in predicting the soil carbon flux of grassland ecosystems for future climate change.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.699-713
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• 2012

Palustrine wetland is often used for development work and green area creation. However, the ecological characteristic of vegetation is not frequently considered in planning. Therefore, this study was conducted to investigate vegetation characteristic according to land-use of palustrine wetland and to provide basic materials in assessment of palustrine wetland and restoration and creation of wetland. Survey sites were caterogized into paddy, field, and mountain. Each category had two sites, so total 6 survey sites were investigated for vegetation. As a result, with a range of 61~92 species, total 216 taxa were confirmed, consisting of 71 families, 168 generic, 187 species, 2 variety 1 forma 1 subforma. Mountain received a high score in the evaluation score range of floristic regional indicator plants, and it was found that there were 10 families and 28 species of naturalized plant. Mountain showed low appearance, and fiddy and field showed relatively high appearance. Naturalized plants with slightly high vegetation cover ratio are Erigeron annuus, Amorpha fruticosa, Dactylis glomerata, Festuca arundinacea, Eragrostis curvula, Trifolium repens, Erigeron Canadensis, Ambrosia trifida, Oenothera odorata, Bidens frondosa, etc. Such naturalized plants should be removed to prevent terrestrialization of wetland and its harmful damages. Long-term monitoring and proper management of naturalized plants are expected to improve palustrine wetland into high quality biotope of rural area in the future.

• Land and Housing Review
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• v.12 no.2
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• pp.13-32
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• 2021

Rapid urbanization has resulted in the unprecedented growth of population in Metro Manila, the Philippines and has led to a 'dual' housing crisis - vacant/unoccupied socialized housing and a chronic housing shortage or delayed housing supply. By developing two GIS-based statistical models, this study is to examine socialized housing in comparison with private housing with respect to location patterns, integration, accessibility, social and economic aspects, and vulnerability to environmental hazards. Multiple regression analysis was integrated with the GIS to identify significant variables that influence the spatial distribution of socialized housing. The comparison between the two regression models has shown that socialized housing is located in areas with inappropriate land use and poor accessibility to transportation facilities and built urban resources. Moreover, both regression models have proven the statistical significance of the vulnerability of socialized housing to environmental hazards. The finding explains how the current housing policies do not address the country's housing crisis, especially for the marginalized and low-income households. Thus, the findings provide implications for urban planners and local decision-makers in reforming the current policy interventions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.38-47
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• 1999

The mixed rural city is adjusting to change by urbanization. The recent landcover change in mixed rural city is an important factor that changes structure and function of regional ecosystem. Landscape ecology is an integrated ecology widely available for environmental science such as nature conservation and sustainable land-use planning. As the concern about environmental quality rises, many studies are trying to create and conservate for biotop. The creation of biotop is related to the plan and management of the effective landuse because the important factor to change the structure and function of ecological area in the country. This study was carried out to establish the foundation of the landuse plan to analyze the change of landuse and to plan the scheme in creating biotop and landuse. We used the approach of ecological landscape and using landscape indices with RS(Remote Sensing) and GIS(Geographic Information System) technology, spatio-temporal variations of areas and distribution of forest patches were examined in the Sunghwan in Chonan from 1985 to 1996. A result of this study showed that the area of forest and paddy decreased by urban sprawl. The size of patch in the forest and agriculture had been smaller and irregular form, heterogeneity of size of forest and agriculture patches within sub-basin was increased, pattern of forest and agriculture patches decreased the corridor and network from 1985 to 1996.

• Spatial Information Research
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• v.2 no.2
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• pp.165-174
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• 1994

Soil loss was estimated by using universal soil loss equation(USLE) through GIS technique in Buyeu area. The expected soil loss is determined from six environmental factors: rainfall, erodibility of selected soil, length and steepness (gradient) of ground slope, crop grown in soil, and land practices used. A scoring system for assessing soil lossrisk has been developed for calculating SLI(Soil Loss Index) by GIS. The scores of six factors multiplied to give a total score which was compared with an chosen classification system to categorize areas of low, moderate and high risk. Finally, a soil loss assessment map was produced by GIS cartographic simulation technique, and this map could be applied in the establishment of regional land use planning.

• Journal of Environmental Impact Assessment
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• v.9 no.3
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• pp.163-176
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• 2000

The purpose of this study is to analyze the pollutant loads and its distribution, and to suggest the management of nonpoint sources in Daechong Reservoir. The loads from point and nonpoint sources such as population, industry, livestock and land use were calculated per stream or river with topography(1:25,000) of the watershed of Daechong Reservoir. The generating pollutant loads were obtained through multiplication of pollutant sources by generating pollutant quantity per unit pollutant source. The effluent point sources loads is defined as loads from wastewater treatment facilities such as domestic, industrial and livestock wastewater treatment facilities, which were calculated through multiplication of effluent flowrates by water quality constituents concentration. Untreated point sources loads were estimated to be 35 % of total point sources loads. The effluent nonpoint sources pollutant loads were obtained through the multiplication of generating nonpoint sources loads by effluent ratios based on previous studies. The effluent nonpoint sources loads have the ratio of 26.2% of total BOD effluent loadings, 20.1% of total T-N effluent loadings, and 10.5% of total T-P effluent loadings. For the reduction of nonpoint sources loads in Daechong Reservoir, silviculture, artificial wet land, and grassed waterways could be applied. And untreated livestock waste scattered can result in nonpoint loadings, so required the livestock wastes treatment facilities and purifying facilities together with the management of shed, pasture, livestock waste storage site and composting site. Finally, remote sensing and GIS should be applied to the identification of distribution of water quality, watershed, the location and scale of nonpoint sources, effluent process during rainfall, for more detailed analysis of nonpoint sources.

• The Journal of Engineering Geology
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• v.3 no.3
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• pp.253-266
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• 1993

GIS technique was applied for ffie work of water supply protection, and GIS rnaps were produced by this technique in Cheong-ju area. They are actual runoff rnap and regional groundwater protection map. The digital database was estabilished for creation of these maps in EGIS(Environmental Geologic information system). A lot of environmental, hydrological and geotedmical data relating to the area were collected from various sources, and used along with the results of the field investigation and laboratorv works in the interpretation of environmental geologic characteristics of the area. These special maps can be applied in the establishment of water supply protection and regional land use planning. For instant, the actaal runoff rnap is very linportant for hydrologic study, and groundwater protection map for susceptibility to groundwater contamination in the area. Actual runoff of the study area was calculated about 148mm using the method of SCS(Soil Consrevation Service) in GIS. The GIS technique was effective in watershed analysis and water balance study.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.3
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• pp.71-83
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• 2020

Resilience is the capacity to maintain essential services under a range of circumstances from normal to extreme. It is achieved through the ability of assets, networks, systems and management to anticipate, absorb and recover from disturbance. It requires adaptive capacity in respect of current and future risks and uncertainties as well as experience to date. The agricultural infrastructures with high resilience can not only reduce the size of the disaster relatively, but also minimize the loss by reducing the time required for recovery. This study aims to evaluate the most suitable drought countermeasures with the analysis of various resilience indices by predicting future agricultural water shortage under land use and climate change scenarios for agricultural areas in Jeju Island. The results showed that the permanent countermeasure is suitable than the temporary countermeasures as drought size and the cost required for recovery increase. Wide-area water supply system, which is a kind of water grid system, is identified as the most advantageous among countermeasures. It is recommended to evaluate the capability of agricultural infrastructure against drought with the various Resilience Indices for reliable assessment of long-term effect.

• Journal of Korean Society of Rural Planning
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• v.12 no.1 s.30
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• pp.37-48
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• 2006

The objectives of this study were to develop an evaluation method of regional vulnerability to agricultural drought and to classify the vulnerability patterns. In order to test the method, 24 city or county areas of Gyeonggi-do were chose. First, statistic data and digital maps referred for agricultural drought were defined, and the input data of 31 items were set up from 5 categories: land use factor, water resource factor, climate factor, topographic and soil factor, and agricultural production foundation factor. Second, for simplification of the factors, principal component analysis was carried out, and eventually 4 principal components which explain about 80.8% of total variance were extracted. Each of the principal components was explained into the vulnerability components of scale factor, geographical factor, weather factor and agricultural production foundation factor. Next, DVIP (Drought Vulnerability Index for Paddy), was calculated using factor scores from principal components. Last, by means of statistical cluster analysis on the DVIP, the study area was classified as 5 patterns from A to E. The cluster A corresponds to the area where the agricultural industry is insignificant and the agricultural foundation is little equipped, and the cluster B includes typical agricultural areas where the cultivation areas are large but irrigation facilities are still insufficient. As for the cluster C, the corresponding areas are vulnerable to the climate change, and the D cluster applies to the area with extensive forests and high elevation farmlands. The last cluster I indicates the areas where the farmlands are small but most of them are irrigated as much.

• Journal of Korean Society of Rural Planning
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• v.21 no.3
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• pp.1-17
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• 2015

The value of rice-fields is being graded down in Korea because it has been estimated only from the size. The purpose of this study is to suggest a management plan in which the location and the size of valuable rice-fields for conservation are based on the results of appraising the worth of ecosystem services of rice-fields in Chungcheongnam-do region. The study is as follows; (1)selecting the indicators for evaluating the ecosystem services of rice-fields considering both general functions and special functions in the regional environment conditions, (2)classifying the grades of rice-fields in ecosystem service values, (3)suggesting the location and the size of valuable rice-fields for conservation, (4)calculating the total economic value of the ecosystem services of rice-fields. The results of this study are that the valuable rice-fields' locations for conservation are the grade I rice-fields and their total area is 100,000ha. Also, the value of the ecosystem services of rice-fields in Chungcheongnam-do region was equivalent to 32.8 trillion won. This amount is over 18 trillion won more than the amount obtained if the total rice-fields in Chungcheongnam-do region were to be transformed to other land-use types. The value of ecosystem services should be considered in the future when appraising the worth of rice-fields, and methods of estimating the ecosystem services of rice-fields need to be developed with a more objective and suitable index.