• Korean Journal of Soil Science and Fertilizer
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• v.14 no.1
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• pp.37-43
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• 1981

This pot experiment was conducted to find out the optimal fertilization ratio of the cations(K: Ca: Mg) in various soil conditions. Soil samples were collected from uncultivated mountains and hills where development for grass lands is under consideration. The optimum ratios were computed by the Homes systematic variation technique. The results were summarized as follows : 1. The optimum fertilization ratios of the cations (K : Ca : Mg) for the high yields of grass-clover mixed sward at various areas were obtained (Table 4) 2. The relatively high optimum fertilization ratios of K in Daegu and Taegwalryong, Ca in Unbong, and Mg in Cheju district gave the high yields of clover in mixed sward. They were positively related to the low contents of the above cations in the soils or the relatively low content ratio comparing with other cations. 3. The yields of clover in mixed sward were seriously affected by the changes in both the fertilization ratio and total concentration of cations comparing to those of the grass yields. As a consequence, total yields, quality, and botanical composition of the mixed sward were also affected. 4. The antagonis among the cations K, Ca, and Mg was known from the point of mineral contents of grass and clover. 5. The equivalent ratio K/(Ca+Mg) or grass was greatly increased by the range of 2.4 and 3.3 in the K-group treatment, which was higher than the critical level 2.2 of grass tetany, otherwise that. of clover by the range of 0.9 and 1.2. Therfore, it may be concluded that if the botanical composition of grass/legume sward is optimum, the incidence of grass tetany can be eliminated.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.40-53
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• 2013

Most of the existing domestic studies to identify the distribution of longevity population and influencing factors oriented confirmatory approach. Furthermore, most of the studies in this research topic simply have used their own definition of spatial unit of analysis or employed arbitrary spatial units of analysis according to data availability. These research approaches can not sufficiently reflect the spatial characteristic of longevity phenomenon and exposed to the Modifiable Aerial Unit Problem(MAUP). This research performed the Exploratory Spatial Data Analysis(ESDA) to identify the spatial autocorrelation of the distribution of longevity population and investigated whether the modifiable areal unit problem in the aspect of scale effect using spatial population data in Korea. We used Si_Gun_Gu and Eup_Myeon_Dong as two different spatial units of regional longevity indicators measured. Then, we applied Getis-Ord Gi* to investigate the existence of spatial hot spots and cold spots. The results from our analysis show that there exist statistically significant spatial autocorrelation and spatial hot spots and cold spots of regional longevity at both Si_Gun_Gu and Eup_Myeon_Dong levels. This result implies that the modifiable areal unit problem does exist in the studies of spatial patterns of longevity population distribution. The demand for longevity researches would be increased inevitably. In addition, there were apparent differences for the global spatial autocorrelation and local spatial cluster which calculated different spatial units such as Si_Gun_Gu and Eup_Myeon_Dong and this can be seen as scale effect of MAUP. The findings from our analysis show that any study in this topic can mislead results when the modifiable areal unit problem and spatial autocorrelation are not explicitly considered.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.224-231
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• 1984

Four kinds of soil conditioners, such as red earth, clayey tidal deposit, silty tidal deposit and tertiary deposit were evaluated for the rice growth and for the effectiveness of soil improvement in sandy paddy soil (Gangseo series) whose percolation and nutrient leaching are usually severe. Experiment was conducted at the farmer's field in Hackpo Ri, Bugog Myeon, Changyeong Gun, Gyeong Nam Province for two years (1980-1981) with using two rice varieties, Milyang 42 for 1980 and cheongcheongbyeo for 1981. For both experimental years, the grain yields were increased on the plots that were treated with soil conditioners compared with nontreated plot. The increase in grain yield was particularly high on the plots treated with clayey tidal deposit and teritary deposit. The dry weight of the plant and the uptake amount of inorganic ingredient tended to increase on the plots of clayey tidal deposit and tertiary deposit during whole rice growing season because of the residual effect of soil conditioners in the second experimental year. Cation exchange capacity, available silicate, exchangeable potassium and active iron was increased by the treatment with the soil conditoners. Especially cation exchange capacity was highest in the tertiary deposit treatment plot. Aggregation content and plastic index were increased for the all treatment plots with soil conditioner, however, hydraulic conductivity was conspicuously decreased by the tertiary deposit and clayey tidal deposit treatments.

• Korean Journal of Environment and Ecology
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• v.27 no.3
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• pp.271-279
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• 2013

The species of Corydalis cornupetala Y.H.Kim et J.H.Jeong Which is belong to the Corydaliaceae is only distributed at the Gyaejeong Forest in Gyeongsan. As one of the spring ephemeral plants, this species has limited growing period. The present study is on site characteristics and vegetation structure in the wild habitats of Corydalis cornupetala Y.H.Kim et J.H.Jeong and offers basic information on habitat conservation including recovery plan. The soil texture is silty loam and soil acidity is ranged as pH 5.4~5.9. The electric conductivity was 0.22-0.50 ds/m and soil organic content is ranged as 7.61~15.78 %. Fifty nine vascular plants were identified from 5 quadrats. According to the two way cluster analysis applied by the PC-ORD, the community was classified as Acer ginnala, Vicia amoena and Stellaria aquatica. The habitat of Corydalis cornupetala Y.H.Kim et J.H.Jeong was determined by the dissimilarity indices rather than the species number of appearance. Species diversity was 1.26, and dominance and evenness were found to be 0.08 and 0.92, respectively.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.331-341
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• 2014

The present study was to survey the site environment, vegetation structure and soil characteristics in the wild habitats of Wikstroemia ganpi in Goheung, Busan and Ulsan, and offers basic information for habitat conservation and restoration. Most of the wild habitats were located at altitudes between 28~242m with inclinations ranged as $0{\sim}40^{\circ}$. The canopy openness was 57.56%. The vegetation structure by the PC-ORD based on the Two Way Cluster Analysis were divided into three groups Community I(Castanea crenata-Pinus densiflora), Community II(Quercus dentata-Pinus thunbergii) and Community III (Pinus thunbergii). The species diversity was 1.3650, and evenness and dominance were found recorded as 0.8666 and 0.1333, respectively. The soil textures were silty loam and sandy loam. The average soil pH was 5.5, electric conductivity was 0.15dS/m, soil organic matter was 2.60% and available phosphorus was 4mg $kg^{-1}$. Correlation coefficients based on environmental factors, vegetation and soil analysis were showed that positive correlations between species diversity and evenness, organic matter and total nitrogen, whereas species slop degree and coverage of herb, diversity and dominance were showed negative correlations.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.1-14
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• 2014

In this study, the change characteristics of urban spatial structure in Daegu were analyzed connecting with urban planning for efficient urban management. Urban development process from 1970 to 2010 in Daegu was analyzed utilizing Getis-Ord $G_i^*$ methodology, a spatial statistical method, and it was identified that Daegu was in the stage of disurbanization. However, as Daegu orients multi-nuclei city, it was difficult to explain the stage of urban development after disurbanization in 2000. Accordingly, to analyze detailed changes in spatial structure in multi-centric areas after 2000, population, land price and employment factor changes were analyzed using Bachi Measurement. According to analytical results, multi-centralization process has been continued in Daegu. Urban core area and Chilgok area showed spatial structure change into distribution process, Ansim area into concentration process, and Seongseo and Talseo area into concentration and distribution process. Therefore, urban planning considering the regional characteristics are needed for efficient urban management.

• Korean Journal of Environmental Agriculture
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• v.4 no.1
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• pp.11-17
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• 1985

A pot experiment was carried out to investigate the effect of Cd and Zn added to soil on the growth, peroxidase activity, chlorophyll content, inorganic components, and interaction between Cd and Zn in corn plant. The results obtained are as follows. Both Cd and Zn reduced dry weight and height of corn plant. Peroxidase activity of leaves increased in higher Cd content of shoot but adverse trend was shown with increasing Zn content of shoots. Chlorophyll contents were significantly decreased with increase of both Cd and Zn content of shoots. Higher soil Cd levels increased N content but decreased P, K, Ca, Mg and $SiO_2$ content in plant. Wherease higher Zn levels in soil increased P and $SiO_2$ content but decreased N, Ca, Mg content in plant. The total Cd and Zn uptake of shoot increased with time but the Cd and Zn content of shoot showed no tendency. Cadmium uptake by Zn application was reduced in higher Zn levels with time while Zn uptake by Cd application showed adverse trend.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.50-56
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• 1983

A study was conducted to evaluate the weed population as affected by repeated application of fertilizers for 15 years (nonfertilized, PK, NK, NPK, NPK+Compost, NPK+Straw and NPK+lime). Alopecurus aequalis authority did not grow at all without P application and lime reduced the population of A. aequalis. Total number of weeds were the largest at 5-10cm soil layer and increased by application of compost and straw. Monochoria vaginalis dominated in NPK+compost and NP plot. Scirpus hotarui dominated in NPK+straw. Both Eleocharis kuroguwai and Potamogeton distinctus dominated in nonfertilized plot. Numbers of M. vaginalis and S. hotarui were larger low pH 6 while that of E. kuroguwai and P. distinctus at pH 6 to pH 7. Incidence of M. vaginalis and S. hotorui was great at pH's lower than 6, while E. kuroguwai and P. distinctus favored pH's ranging from 6 to 7.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.67-79
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• 2020

Plans to mitigate overheating in urban areas requires the identification of the characteristics of the thermal environment of the city. The key information is the distribution of higher and lower temperatures (referred to as "hotspot" or "coldspot", respectively) in the city. This study aims to identify the areas within Jeonju City that are suffering from increasing land surface temperatures (LST) and the factors linked to such this phenomenon. To identify the hot and cold spots, Local Moran's I and Getis-Ord Gi^* were calculated for the LST based on 2017 images taken using the thermal band of the Landsat 8 satellite. Hotspot analysis revealed that hotspot regions, (the areas with a high concentration of Land Surface Temperature) are located in the old town area and in industrial districts. To figure out the factors linked to the hotspots, a correlation analysis, and a regression analysis taking into account environmental covariates including Normalized Difference Vegetation Index (NDVI) and land cover. The values of NDVI showed that it had the strongest effect on the lowering LSTs. The results of this study are expected to provide directions for urban thermal environment designing and policy development to mitigate the urban heat island effect in the future.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.3
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• pp.183-199
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• 1976

1. The cultivated land in Korea has originally low fertility resulting in high dependence to fertilizers. 2. The total fertilizer requirement calculated by the Office of Rural Development (ORD) in 1976 was about 1,153 thousand mts, and the total amount of supply planned by the Ministry of Agriculture and Fishery was 1,010 thoushand mts which is close to the amount calculated by ORD. However, there is some gap between the amount of recommended (N, 11.6; $P_2O_5$: $K_2O$, 7.3kg/10a> and supply planned (N, 12.0; $P_2O_5$, 6.3; $K_2O$. 4.8kg/10a) fertilizers for each elements per unit area 3. For 15 years from 1960 to 1975 the fertilizer consumption of nitrogen was roughly increased from 200,000 mts to 500,000 mts; phosphorus, from 50,000 to 250,000 mts; potassium, from 10, 000 to 170,000 mts; accounting 2.5, 5, and 17 times of increase respectively. 4. The total fertilizer consumption for 5 years from 1967 to 1971 was about 100,000 mts and another 5years from 1971 to 1975 was 300,000 mts indicating three times increase. 5. The direct factors influenced to the increase of fertilizer consumption in recent years are 1) the dissemination of high yielding Tongil type rice varieties which are resistant to heavy fertilization 2) high price policy for agricaltural products 3) increased cultivation of vegetables:, fruits, and forages which require high level of fertilizers. The indirect factors are 1) dissemination of new improved agricultural techniques, 2, improvement of cultivated land conditions through irrigation system and land reform, 3) increased supply of silicate fertilizers, and 4) increase of farm income. 6. The percentage of total fertilizer consumption by rice (32%) and barley (25%) is about 57%. The ratio of total fertilizer consumption by vegetables and forages is expected to increase greatly. 7. Based on the increasing tendency of cultivated land and yield per unit area for last 10 years in each crop, total fertilizer consumptions in 1980, 1990, and 2000 year are estimated to 1,290,000, 1,580,000 and 1,870,000 mts respectively.