• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.241-249
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• 2022

Humans and wild birds coexist in cities, where habitat fragmentation due to urbanization threatens the habitat and movement of birds. In this study, in order to identify landscape features associated with wild bird collide, we characterized landscape composition within a 500 m radius and points of wild bird carcasses in Suwon-city, South Korea. Dead birds were identified as having a Normalized Difference Vegetation Index (NDVI) of 0.3, Normalized Difference Built-up Index (NDBI) of -0.05, and Normalized Difference Water Index (NDWI) of -0.16 at the points of collide. And there were NDVI of 0.34, NDBI of -0.01, NDWI of -0.18, building height of 13.8 m, and soundproof wall length of 227.3 m within a radius of 500 m. Land cover type was dominated by grassland, used area, and bare land. In particular, the edges of urbanized areas, where apartments bordered forests, reservoirs, and golf courses, were identified as high-risk spaces. In order to minimize bird mortality risk in urban environments, the impact of changes to a vertical landscape should be reviewed from an environmental impact assessment approach. In addition, a preventive management plan that considers the temporal and spatial features that wild animals can safely avoid and adapt to in urbanized spaces should be prepared.

• Journal of Wetlands Research
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• v.22 no.1
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• pp.49-58
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• 2020

The excessive use of fertilizer and compost in agricultural land increases the accumulation of nutrients in soil. The surplus nutrients in soil transported through surface and sub-surface flow can lead to water pollution problems and algal bloom. Moreover, nutrient accumulation and continuous crop cultivation changes the physical structure of the soil, which increases the potential of nutrient. The cultivation in the Daecheong Lake reservoir area may have a direct effect on the lake's water quality due to leaching and releasing of nutrients when water level rises. This research was carried out to analyze the physical and chemical properties of soil in the agricultural areas surrounding Daecheong Dam reservoir to provide basic data available for the establishment of Daecheong Lake water quality management measures. The soil of the Daecheong Lake reservoir was classified as sandy Loam, where surplus nutrients can be transported. Chemical compositions in the soil were found to be significantly affected by use of different fertilizer amounts. Nutrient outflow occurred during spring rainfall events from the rice paddy fields, whereas excess nutrients from summer to fall seasons originated from dry paddy fields. Nutrient outflow from dry paddy fields is mainly from sub-surface flow. Organic agricultural wastes from agricultural land and excessive vegetation inside the river was also evaluated to contribute to the increase in organic matter and nutrients of the river. The results can be used to select the priority management area designation and management techniques in the Daecheong Lake for water quality improvement.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.24-30
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• 1986

This experiment was carried out in order to study the effect of fertilizer application and seasonal changes on the productivity of the native reed (Phragmites communis Trinius) on the reclaimed tidal flate in Chonnam province. The samples of reed were taken at about 30-days interval from May to October, 1982 and evaluated plant height, blade & sheath-stem ratio, grass yield, the feed compositions and in vitro dry matter digestibility (IVD). The results are summarized as follows: 1. Plant height, grass yield, crude protein content and in vitro dry matter digestibility of the reed were significantly increased by fertilizer application, and ADF content was significantly decreased. 2. According to the significance test of coefficience, there was a significant negative correlation (P<0.05) between in vitro dry matter digestibility and plant height, grass yield, and the content of crude fiber and ADF, but a positive correlation (P<0.05) between in vitro dry matter digestibility and blade & sheath-stem ratio, and the content of crude protein and crude fat.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.1-19
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• 2020

A river bed which is submerged in water at high flow and becomes part of the river at low flow, serves as a bridge between the river and the land. The channel bar creates a unique ecosystem with vegetation adapted to the particular environment and the water pool forms a wetland that plays a very important role in the environment. To evaluate anthropogenic impacts on the river bed in the Middle Yeongsangang River, the fluvial landforms in the stream channel were analyzed using multi-temporal remotely-sensed images. In the aerial photograph of 2005 taken before the construction of the large weirs, oxbow lakes, mid-channel bars, point bars, and natural wetlands between the artificial levees were identified. Multiple bars divided the flow of stream water to cause the braided pattern in a particular section. After the construction of the Seungchon weir, aerial photographs of 2013 and 2015 revealed that most of the fluvial landforms disappeared due to the dredging of its riverbed and water level control(maintenance at 7.5El.m). Sentinel-2 images were analyzed to identify differences between before and after the opening of weir gate. Change detection was performed with the near infrared and shortwave infrared spectral bands to effectively distinguish water surfaces from land. As a result, water surface area of the main stream of the Yeongsangang River decreased by 40% from 1.144km² to 0.692km². A large mid-channel bar that has been deposited upstream of the weir was exposed during low water levels, which shows the obvious influence of weir on the river bed. Newly formed unvegetated point bars that were deposited on the inside of a meander bend were identified from the remotely sensed images. As the maintenance period of the weir gate opening was extended, various habitats were created by creating pools and riffles around the channel bars. Considering the ecological and hydrological functions of the river bed, it is expected that the increase in bar areas through weir gate opening will reduce the artificial interference effect of the weir.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.7-14
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• 2011

We investigated moth communities in Samcheok, Korea, to elucidate the influence of the East Coast Fire in 2000. Moths were collected with UV light traps 4 times a year from 2006 to 2009 at 3 sites: Unburned area (Site 1), Surface fire area (Site 2), and Crown fire area (Site 3) sites, respectively. A total of 3,804 individuals belonging to 727 species from 30 families were captured at the 3 study 1,727 individuals of 505 species (27 families) at Site 1, 1,193 individuals of 353 species (24 families) at Site 2, and 885 individuals of 340 species (25 families) at Site 3. Species richness and individuals of Noctuidae, Pyralidae, Geometridae, and Tortricidae were the highest at all 3 sites. All of species richness, individuals, and species diversity (H') were the highest in Site 1 for 4 years. The index of similarity (${\alpha}$-Index) was higher between Site 2 and 3 in 2006, while higher between Site 1 and 2 in 2009. Moths were grouped into 16 categories by hosts of the larval stage. Individuals of moths of herbaceous feeding habit continuously decreased at Site 3, but proportion of individuals of tree feeding habits continuously increased. The present results showed that moth communities was relatively recovered according to vegetation change after forest fire and regeneration of moth communities in surface fire area was more faster than in crown fire area.

• Journal of Environmental Science International
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• v.24 no.11
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• pp.1405-1415
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• 2015

This study is conducted to determine the damage, distinguish the types and identify the restoration by that type for 13 Korea national parks out of 21. There are 21 Korea national parks are in Korea covering 6.67% of the country or $6,656km^2$ ($3,902km^2$ on land and $2,754km^2$ in the sea) currently since the area around Jirisan ($440km^2$) was designated as the first Korea national parks in 1967. With the cancellation of entrance admission on Korea national parks since 2007, annual visitors to the Korea national parks have grown from 37 millions in 2008 to 46 millions by 2013 and continue to grow due to numerous leisure activities, alpine activities and social changes. As such, Korea national parks are natural resource with high value to be conserved and are attracting significant attention as recreational spaces for people at the same time. On the other hand, there have been issues of soil erosions or disturbed vegetation due to increased number of visitor to the national parks. Korea national parks area damage to its type and damage characteristics to analyse the 13 Korea national parks out of 21 on July 2012 March, Korea national parks over the subjects of the National Park from damaged area status Survey analysis by the Korea National Park Service. As a result, 203 million units in the 16 Korea national parks damaged land of the reform package during ecological trail (including non-regular hiking trails) 153 (77.66%), damaged valleys 20(9.14%) independent damaged area, 13 disconnected ecological axis(7.61%), closed trail(2.03%) (3.55%), and line type damage(like a non-regular hiking trails) appears to be a high ratio. Korea national parks damaged land of the results identified, by contrast ratio and the annual number of visitors Bukhansan national park(49.26%), Gyeongju national park(23.65%) damaged land rates, such as Seorasan national park(4.93%), Songnisan national park (4.43 %), Gyeryongsan national park(3.45%), and the annual number of visitors be similar result. The National Park Service has been reporting on damages and restorations but damages and their types have not been established yet. Damages have been generally studied and categorized on hiking trails due caused by heavy traffic on them but the reports were limited on hiking trails only. Since damage to the Korea national parks are not limited on the hiking trails, it is necessary to determine damages in various aspects. Thus, in this study, damage types, spatial characteristics, causes and restorations are analyzed based on the survey results of damages to national parks in order to provide a basis for the efficient management and operation of the Korea national parks.

• Current Research on Agriculture and Life Sciences
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• v.21
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• pp.39-47
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• 2003

The object of this study was to analyze influence which Black locust afforestation affected to soil, to research change of soil environment of Black locust planted stand and adjacent stands through comparative analyzing physichemical property of soil of them. It was investigated that the soil texture of Black locust planted stand and the adjacent stands was mostly SL. and LS. According to this result I could know that transformation of soil texture by vegetation easily happened because transformation soil texture results from the parent rock. I could ascertain that difference existed between Black locust planted stand and the other stands in soil pH and Carbon content of planted stand of Black locust pH, contents of Available $P_2O_5$ Carbon, Total Nitrogen. In other words, pH and Carbon content of Black locust planted stand were lower than that of Oak forest, higher than that of Pine forest. These results showed that Black locust was which fix nitrogen. I could infer that Black locust afforestation made forest soil fertilized. In soil of Black locust planted stand and the adjacent stands, statistical value appeared highly in pH and existed in content of Carbon, Total nitrogen, too. And high interrelationship appeared in the order of pH, C/N Ratio, CEC, Total nitrogen content was in each stands. I suppose that the trespassing extent of Black locust to Oak forest and Pine forest which are adjacent to planted stand of Black locust is different because of low pH, lackness of Available $P_2O_5$ Carbon, and what not.

• Economic and Environmental Geology
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• v.56 no.5
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• pp.619-628
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• 2023

In this study, we investigated the feasibility of calcium sulfate fertilizer as a stabilizing agent for As and Hg contaminated farmland soil and its stabilization characteristics in 3 different physical forms (particulate, powder, and solution) through a pot experiment including 34 days of lettuce growth. As and Hg contents of the lettuce grown in the stabilized soils were decreased by at least 70%. However the lettuce yield of the soil stabilized with the solution agent was decreased by 46% due to the overabundance of the nutrients from the solution agent. Thus, if a solution-type agent is planned for agricultural farmland soil stabilization, additional tests for optimal dosage are needed to preserve vegetation growth. In Hg fractionation, a lower concentration of elemental fractions and a higher concentration of residual/sulfide fractions were identified in the soils stabilized with the solution, powder, and pariculate agents in descending order while there were no significant changes in As fractionation. Overall results suggest that calcium sulfate fertilizer can be used as a stabilizing agent, and a solution-type agent could be used when the operation of heavy machinery for the soil stabilization process is impossible.

• Journal of Korean Society of Disaster and Security
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• v.16 no.4
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• pp.9-18
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• 2023

Climate change affects the safety of river revetments, especially those associated with external flooding. Research on slope reinforcement has been actively conducted to enhance revetment safety. Recently, technologies for producing embankment blocks using recycled materials have been developed. However, it is essential to analyze the impact of block shapes on the flow characteristics of exclusion zones for revetment safety. Therefore, this study investigates the influence of revetment block shapes on the hydraulic characteristics of revetment surfaces through 3D numerical simulations. Three block shapes were proposed, and numerical analyses were performed by installing the blocks in an idealized river channel. FLOW-3D was used for the 3D numerical simulations, and the variations in maximum flow velocity, bed velocity beneath the revetment, and maximum shear stress were analyzed based on the shapes of the revetment blocks. The results indicate that for irregularly sized and spaced revetment blocks, such as the natural stone-type vegetation block (Block A), when connected to the revetment in an irregular manner, the changes in flow velocity in the revetment installation zone are more significant than those for Blocks B and C. It is anticipated that considering the topographical characteristics of rivers in the future will enable the design of revetment blocks with practical applicability in the field.

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.45-54
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• 2014

This study was carried out to investigate the ecological succession sere and conservative value, and to provide the basic data in Woonsooam Valley, in Jogyesan (Mt.) (altitude 884m), Suncheon City, Korea by analysing the structure of the plant community. Fifteen plots (size is $20m{\times}20m$) were set up at an altitude of range from 255m to 495m. As a result of analysis of DCA which is one of the ordination technique, the plant communities were divided into five groups which are community I (Pinus densiflora community), community II (Quercus variabilis-Quercus serrata community), community III (Q. serrata-Q. variabilis community), and community IV (Carpinus tschonoskii-Q. serrata community) and community v(Deciduous broad-leaved forest community). We found out that the vegetation of the study site located in the South Temperate Climate Zone. The study site is found out that Q. serrata community 34.4%, part of slope in valley is the distribution that dominant species is Q. serrata-Q. variabilis community 32.1%. And in valley showed Carpinus tschonoskii community 5.5%. And Sasa borealis was dominant species in the shrub layer. We couldn't supposed that the ecological succession sere of the study site, however we should do a long-term monitoring to investigate the changes of the ecological succession each plant community, According to the index of Shannon's diversity (unit: $400m^2$), community III was ranged from 1.0102 to 1.1013, community V was 0.9945, community II was ranged from 0.7913 to 1.1503, community IV was ranged from 0.8081 to 1.0749 and community I was 0.9273.