• Journal of Mushroom
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• v.18 no.1
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• pp.1-9
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• 2020

Mycorrhiza refers to the association between a plant and a fungus colonizing the cortical tissue of the plant's roots during periods of active plant growth. The benefits afforded by plants from mycorrhizal symbioses can be characterized either agronomically, based on increased growth and yield, or ecologically, based on improved fitness (i.e., reproductive ability). In either case, the benefit accrues primarily because mycorrhizal fungi form a critical linkage between plant roots and the soil. The soilborne or extramatrical hyphae take up nutrients from the soil solution and transport them to the root. This mycorrhizae-mediated mechanism increases the effective absorptive surface area of the plant. There are seven major types of mycorrhizae along with mycoheterotrophy: endomycorrhizae (arbuscular mycorrhizae, AM), ectomycorrhizae (EM), ectendomycorrhizae, monotropoid, arbutoid, orchid, and ericoid. Endomycorrhizal fungi form arbuscules or highly branched structures within root cortical cells, giving rise to arbuscular mycorrhiza, which may produce extensive extramatrical hyphae and significantly increase phosphorus inflow rates in the plants they colonize. Ectomycorrhizal fungi may produce large quantities of hyphae on the root and in the soil; these hyphae play a role in absorption and translocation of inorganic nutrients and water, and also release nutrients from litter layers by producing enzymes involved in mineralization of organic matters. Over 4,000 fungal species, primarily belonging to Basidiomycotina and to a lesser extent Ascomycotina, are able to form ectomycorrhizae. Many of these fungi produce various mushrooms on the forest floor that are traded at a high price. In this paper, we discuss the benefits, nutrient cycles, and artificial cultivation of mycorrhizae in Korea.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.286-292
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• 2010

Native oak tree species dominate the deciduous forests of South Korea. Although the acorns of these oak trees represent the main food source for many wildlife species, information pertaining to their nutrient composition and associated seasonal changes is limited. Thus, the objective of this study was to describe the seasonal changes in the acorn nutrient composition of six oak species in terms of nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), and sodium (Na) concentrations, Quercus acutissima, Q. aliena, Q. mongolica, Q. variabilis, Q. dentata, and Q. serrata. The results indicated that N concentrations of Q. aliena acorns were constant, whereas those of Q. dentata changed over the seasons. Those of Q. acutissima acorns were higher in summer and autumn but Q. mongolica acorns were higher in spring and summer. Q. serrata acorns were highest in autumn but Q. variabilis acorns were found to be the lowest in N concentration. P concentrations of acorns of six species tended to decline in the summer but increased in the spring and autumn. Ca and Mg concentrations showed an obvious trend of decline over the seasons for all species except Q. mongolica. Na concentrations of Q. aliena, Q. dentata, and Q. serrata acorns were constant over the seasons whereas those of Q. dentata tended to increase. Q. variabilis acorns were highest in autumn but Q. acutissima acorns were lowest in Na concentration. Overall, these results showed that acorn nutrient composition varies by season, and that the nature of the variability is largely species dependent.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.90-102
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• 2017

In this study, various types of nutrient models were tested by using two tears's water quality data collected from the stormwater wetland in Korea. Based on results, most important factor influencing nitrogen removal was hydraulic loading rate, which indicates that surface area of wetland is more important than its volumetric capacity, and model proposed by WEF was found to give a least error between measured and calculated values. For the phosphorus, in case assuming a power relationship between rate constant and temperature, the best prediction result were obtained, but temperature was most sensitive parameter affecting phosphorus removal. In addition, denitrification was always a limiting step for the nitrogen removal in this particular wetland mostly due to the lack of carbon source and high dissolved oxygen concentration. In this paper, several alternatives to improve nitrogen removal, including proper arrangement and designation of wetland elements and use of floating plants or synthetic fiber mat to control oxygen level and to capture the algal particles were proposed and discussed.

• Korean Journal of Environment and Ecology
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• v.19 no.2
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• pp.150-161
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• 2005

Soraksan National Park and Odaesan National Park, that are 20.7 km apart, should play an important role as habitats and corridors for wildlife because they are located in the center of Baekdudaegan. However, landscape features such as small area, fragmentation, and geographic isolation seem to impede the proper ecological functions of these two national parks. Using GIS technique, we examined the pattern of fragmentation in these two national parks and adjacent regions (Sokcho-si, Goseong-gun, Inje-gun, Yangyang-gun, and Hongcheon-gun) encompassing a total of $4573.5km^2$ in area. We then selected the patches suitable for an endangered carnivorous species, leopard cat, based on habitat conditions, and identified the network and stepping stone among patches to enable leopard cats to migrate. Diverse roads and artificial facilities in the study area generated a total of 24,701 patches: 39 patches among these were selected as potential habitats upon considering the habitat condition such as vegetation types and minimum area for leopard cat. Three patches nearby Gyebangsan and Bangtaesan were identified as a potential network center to relieve the effects of fragmentation and isolation of the two national parks. Our results also showed that patches containing Jombongsan and Bangtaesan would act as a source patch from there leopard cats can disperse to both national parks. It is an urgent task to identify the pattern of fragmentation and the connectivity between patches in national parks and adjacent areas for wildlife conservation because almost all national parks confront land- scape problems similar to the two national parks examined in this study.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.651-664
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• 2014

Recently, the demands of accurate forest carbon stock estimation and mapping are increasing in Korea. This study investigates the feasibility of two methods, k-Nearest Neighbor (kNN) and Regression Tree Analysis (RTA), for carbon stock estimation of pilot areas, Gongju and Sejong cities. The 3rd and 5th ~ 6th NFI data were collected together with Landsat TM acquired in 1992, 2010 and Aster in 2009. Additionally, various vegetation indices and tasseled cap transformation were created for better estimation. Comparison between two methods was conducted by evaluating carbon statistics and visualizing carbon distributions on the map. The comparisons indicated clear strengths and weaknesses of two methods: kNN method has produced more consistent estimates regardless of types of satellite images, but its carbon maps were somewhat smooth to represent the dense carbon areas, particularly for Aster 2009 case. Meanwhile, RTA method has produced better performance on mean bias results and representation of dense carbon areas, but they were more subject to types of satellite images, representing high variability in spatial patterns of carbon maps. Finally, in order to identify the increases in carbon stock of study area, we created the difference maps by subtracting the 1992 carbon map from the 2009 and 2010 carbon maps. Consequently, it was found that the total carbon stock in Gongju and Sejong cities was drastically increased during that period.

• Journal of Environmental Impact Assessment
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• v.28 no.1
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• pp.23-34
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• 2019

Global warming becomes a serious issue that poses subsidiary issues like a sea level rise or a capricious climate over the world. Because of severe heat-wave of the summer in Korea in 2016, a big attention has been focused on urban heat island since then. Not just about heat-wave itself, many researches have been concentrated on how to adapt in this trendy warming climate and weather in a small scope. A big part of existing studies is mitigating "Urban Heat Island effect" and that is because of huge impervious surface in urban area where highly populated areas do diverse activities. It is a serious problem that this thermal context has a high possibility causing mortality by heat vulnerability. However, there have been many articles of a green infrastructures' cooling impact in summer. This research pays attention to measure cooling effect of a street planting considering urban canyon and type of green infrastructures in neighborhood scale. This quantitative approach was proceeded by ENVI-met simulation with a spatial scope of a commercial block in Seoul, Korea. We found the dense double-row planting is more sensitive to change in temperature than that of the single-row. Among the double-row planting scenarios, shrubs which have narrow space between the plant and the land surface were found to store heat inside during the daytime and prevent emitting heat so as to have a higher temperature at night. The quantifying an amount of vegetated spaces' cooling effect research is expected to contribute to a study of the cost and benefit for the planting scenarios' assessment in the future.

• Journal of the Korean GEO-environmental Society
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• v.22 no.12
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• pp.65-70
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• 2021

River-side Embankment collapse involves various causes. The embankment collapse due to internal erosion around embedded structures reaches up to more than 10% in Korea. Many studies are being attempted to prevent from the collapse of the embankment rooted from overtopping and instability as well as internal erosion. One of them is the study on the application of biopolymers. The application of biopolymers to soils are divided into enhancing strength, vegetation and erosion resistance. This study investigated the effect of biopolymer treated soil on erosion resistance. The main goal of the study is to obtain basic data for real-scale experiments to verify the effectiveness of biopolymer treated soil embankment including a review of the collapse pattern in the model embankment with various test conditions. The optimized experimental conditions were selected by examining the erosion patterns according to each induction path with three compaction degree of the model embankment. As a result of the experiment, the internal erosion rate in the embankment to which the biopolymer treated soil was applied is greatly reduced, and it could be concluded that it might be applied to the actual embankment. However, in this study, the conclusion was drawn only within the scaled-down model embankment. In order to practically apply the biopolymer treated soil to the embankment, the study considering the scale effect would be needed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1B
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• pp.161-168
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• 2008

The ecological environmental zones in coastal area, like tidal flat and salt marsh, were gradually decreased due to large scale of coastal development projects, reclamation and so on. Therefore, the development of artificial tidal flat and salt marsh has been emphasized in coastal area as mitigation concept and studies on related this background has performed. But studies on the quantitative evaluation for degree of restoration were insufficient. In this paper, as a fundamental study for evaluation of restoration on the creation of ecological environmental zones in coastal area, it was conducted that the monitoring and experiment for bio-chemical factors (bio-diversity, population and biomass of macro-benthos, survival ratio of reed, the number of heterotrophic bacteria and physico-chemical characteristics such as COD, IL, TN, TP and pH) using a in-situ pilot plant of tidal flat (Zone. P1) and salt marsh (Zone. P2), which was distinguished by content of dredged soil, in Jinudo, Nakdong estuary. From results of this study, the restoration index (RI), for evaluation concerning degree of restoration on the creation of ecological environmental zones in coastal area, was suggested and quantitative evaluation was performed using a restoration index (RI).

• Korean Journal of Plant Resources
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• v.37 no.2
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• pp.137-148
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• 2024

The purpose of this study is to investigate the weather, soil characteristics, and location environment of Pimpinella brachycarpa natural habitats in order to gather the essential information for the conservation of these habitats. P. brachycarpa are distributed throughout Korea and are mainly found to grow in shady and humid areas between 500 and 1,200 m above sea level. The average annual temperature in Mt. Duta was 13.1℃, and the average annual precipitation in Mt. Jungwon was 1,509 mm, which was higher than in other regions. The pH ranged from 4.42 to 4.97, indicating slight acidity. The total N content ranged from 0.18% to 0.68%, and the available P ranged from 13.43 to 531.56 mg/kg, demonstrating notable regional variations. The species diversity index (H') was highest at Mt. Ilwol, measuring 1.713. The evenness (J') ranged from 0.983 to 0.993, and the dominance (D') ranged from 0.007 to 0.017. The similarity index was very low, averaging 24.86%, and it was divided into communities of Wilson's elm (Ulmus davidiana var. japonica) and communities of Korean maple (Acer pseudo-siebodianum).

• Ecology and Resilient Infrastructure
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• v.8 no.1
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• pp.64-78
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• 2021

This study was conducted to find out the effect of the construction and operation of river-crossing structures on the habitat landscape characteristics in the Geum-gang River, South Korea. A total of three study reaches were selected in the downstream of the Daecheong Dam: the Buyong-ri reach, which is a control that is not affected by the construction and operation of the weir of the Four Rivers Project and Sejong-bo Weir reach and Gongju-bo Weir reach of the upper and lower sections of each weir that are affected by the weir construction and operation. The habitat type was classified, and then the structural characteristics of the landscape were analyzed using aerial photographs taken before and after the construction of the Daecheong Dam, before and after the construction of the weir, and before and after the weir gate operation. After the construction of Daecheong Dam in Geum River, the area of the bare land greatly decreased, and the area of grassland and woodland increased in the downstream of the dam. In addition, the patch number in the river landscape increased, the patch size decreased, and the landscape shape index and the habitat diversity increased. Therefore, after the construction of the dam, the bare land habitat was changed to a vegetated habitat, and the habitat was fragmented and diversified in the downstream of the dam. After the construction of the weirs, the area of open water increased by 18% in the Sejong-bo reach and by 90% in the Gongju-bo reach, and the landscape shape index of the open water decreased by 32% in the Sejong-bo reach and by 35% in the Gongju-bo reach, and the habitat diversity index decreased to 25% in the Sejong-bo reach and to 24% in the Gongju-bo reach. Therefore, the open water habitat was expanded, the shape of the habitat was simplified, and the habitat diversity decreased according to the construction of the weirs. After water-gate opening of the weir, the bare land that disappeared after the construction of the weir reappeared, and the landscape shape index and habitat diversity index increased in both terrestrial and open water habitats. Therefore, it was found that the landscape characteristics of the river habitats were restored to the pre-construction of the weir by the operation of the weir gate. The effect of weir gate opening was delayed in the downstream than in the upstream of the weir. Although the characteristics of the landscape structure in the river habitat changed due to the construction of the river-crossing structures, it is thought that proper technology development for the ecological operation of the structures is necessary as the habitat environments can be restored by the operation of these structures.