• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.539-546
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• 2010

To investigate the variation of anion concentrations in relation to forest type, forest-related factors, forest survey and anion concentrations measurement were carried out on the 52 quadrats located at the national forest areas in Yangyang-gun, Kangwon-do. The relationship between anion concentrations and forest-related factors were correlated. Total mean of anion concentration was 2,405 ea/$cm^3$, which was slightly higher than general figures 2,000ea/$cm^3$. Highly significant positive correlations were observed between anion concentrations and soil moisture contents, and also between anion concentrations and altitude. Significant positive correlations were observed between anion concentrations and topography. Anion concentrations were significantly different among soil moisture levels. Mean anion concentration were highest at 4,524.4ea/$cm^3$ in on wet sites, and followed slightly wet sites and moderate sites. Mean anion concentrations was highest on valley sites at 3,372.4ea/$cm^3$, followed by slope and ridge areas. Mean anion concentrations measured before noon was highest at 3,133.4ea/$cm^3$, and measurements during 12:00~15:00 and after 15:00, showed relatively low anion concentrations. Mean anion concentrations was highest at mixed deciduous forests at 3,503.9ea/$cm^3$, followed by oak forests, pine forests, and pine-oak forests. Results of this study are expected to be used in planning therapeutic forests.

• Economic and Environmental Geology
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• v.13 no.3
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• pp.185-192
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• 1980

The rocks exposed in the investigation area are andesite of Late Cretaceous age, and syenite and aplitic granite of Bulgugsa Series of Early Cretaceous Period, which is intruded in the older andesitic rock. The strike and dip of major joint is $N10^{\circ}$ to $60^{\circ}E$, and $70^{\circ}SE$ to vertical respectively. According to seismic exploration, lower velocity zone, deemed to be fractured and/or crushed zone, is appeared along the gully center of east flank of the area. Test drilling shows that andesite bedrock is mostly very hard, massive, and very fine to medium grained and has almost 100 percent RQD and core recovery. In comparision with andesitic bedrock, intruded syenite cores show that it is highly crush especially at the depth from 55m to 63m.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.317-325
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• 2015

An adequate downscaling of synoptic forecasts is a prerequisite for improved agrometeorological service to rural areas in South Korea where complex terrains and small farms are common. In this study, geospatial schemes based on topoclimatology were used to scale down the Korea Meteorological Administration (KMA) temperature forecasts to the local scale (~30 m) across a rural catchment. Then, using these schemes, local temperatures were estimated at 14 validation sites at 0600 and 1500 LST in 2013/2014 and were compared with the observations. The estimation errors were substantially reduced for both 0600 and 1500 LST temperatures when compared against the uncorrected KMA products. The improvement was most notable at low lying locations for the 0600 temperature and at the locations on west- and south-facing slopes for the 1500 LST temperature. Using the downscaled real-time temperature data, a pilot service has started to provide the field-specific weather information tailored to meet the requirements of small-scale farms. For example, the service system makes a daily outlook on the phenology of crop species grown in a given field using the field-specific temperature data. When the temperature forecast is given for next morning, a frost risk index is calculated according to a known relationship of phenology and frost injury. If the calculated index is higher than a pre-defined threshold, a warning is issued and delivered to the grower's cellular phone with relevant countermeasures to help protect crops against frost damage.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.1
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• pp.17-25
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• 2013

In this paper we interpreted the changes in wind field over complex mountainous terrains. The results of our study can be applied for predicting the direction of fire spread and for establishing strategies for fire prevention. The study area is bounded by $12{\times}12$ km domains of the Samcheok's long-term ecological research (LTER) site located in the east coast, in which a large-fire had occurred from 7 to 13 April 2000. Because of the area's complex topography, we compared the result of the Weather Research and Forecasting (WRF) mesoscale model with those observed by four automated weather stations. The WRF simulation overestimated the wind speed by 5 to 8 m/s (~200%) in comparison with those from four automated weather stations. The wind directions observed by the AWSs were from various directions whereas those from WRF model were mostly west wind at all stations. Overall, the simulations by the WRF mesoscale models were not appropriate for the estimation of microscale wind fields over complex mountainous areas. To overcome such inadequacy of reproducing the wind fields, we employed the ENVI-met model over Samcheok's LTER site. In order to test the model's sensitivity with the terrain effects, experimental simulations were conducted with various initial conditions. The simulation results of the ENVI-met model showed a reasonable agreement in wind speeds (about 70% accuracy) with those of the four AWSs. Also, that the variations in wind directions agreed reasonably well with changes in terrain effect. We concluded that the ENVI-met model is more appropriate in representing the microscale wind field over complex mountain terrains, which is required to predict fire spread and to establish strategies for forest fire prevention.

• The Journal of Engineering Geology
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• v.8 no.2
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• pp.175-188
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• 1998

This paper describes the internal structures and K-Ar ages of fault gouges collected from the Dongnae fault zone. This fault zone is internally zoned and occurs in the multiple fault cores. A fault core consists of thin gouge and narrow cataclastic zones that are bounded by a much thicker damage zone. Intensity of deformation and alteration increases from damage zone through cataclastic zone to gouge zone. It is thought that cataclasis of brittle deformation was the dominant strain-accomodation mechanism in the early stage of deformation to form the gouge zone and that crushed materials in the regions of maximum localization of fault slip subsequently moved by cataclastic flow. Deformation mechanism drastically changed from brittle processes to fluid-assisted flow along the gouge zone as the high porosity and permeability of pulverzied materials during faulting facilitated the influx of the hydrothermal fluids. Subsequently, the fluids reacted with gouge materials to form clay minerals. Fracturing and alteration could have repeatedly taken place in the gouge zone by elevated fluid pressures generated from the reduction of pore volume due to the formation of clay minerals and precipitation of other materials. XRD analysis revealed that the most common clay minerals of the gouge zones are illite and smectite with minor zeolite and kaolinite. Most of illites are composed of 1Md polytype, indicating the products of hydrothermal alteration. The major activities of the Dongnae fault can be divided into two periods based upon K-Ar age data of the fault gouges : 51.4∼57.5Ma and 40.3∼43.6Ma. Judging from the enviromental condition of clay mineral formation, it is inferred that the hydrothermal alteration of older period occured at higher temperature than that of younger period.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.708-721
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• 2019

This study was conducted to understand the plant community structure characteristics of warm-temperate forest in Geoje Island. Survey sites were set up on ridges, valleys, and slopes where evergreen broad-leaved trees predominated or distributed in canopy, sub-canopy, or shrub layers at Chunjangsan(Mt.). Thirty-one sites were located in the areas, such as vegetation community, ridges, valleys, and slopes, to observe vegetation structure and location changes. The community classification with TWINSPAN identified six groups: Neolitsea sericea-Platycarya strobilacea, N. sericea-Styrax japonicus, N. sericea-Euonymus oxyphyllus, Pinus thunbergii-N. sericea, N. sericea-Quercus serrata, and Q. variabilis-P. strobilacea. Considering the results of previous studies that reported that the successional pattern of the warm temperate forests progressed from deciduous to evergreen forests, the regions predominated by deciduous communities such as P. thunbergii, Q. serrata, P. strobilacea, Zelkova serrata, and Q. variabilis, is likely to transform into the evergreen forest predominated by N. sericea. The relationship between the impact of the environmental factors and the vegetation distribution showed that slope, Na +, K +, electrical conductivity, and clay among physical properties had direct or indirect effects on vegetation distribution.

• Spatial Information Research
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• v.7 no.1
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• pp.1-12
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• 1999

The DTM(Digital Terrain Model) in GIS(Geographical Information System) shows the elevation from interpolation using data points surveyed. In panoramic flat landform, pixel size, resolution of source data may not be the problem in using DTM However, in mountainous landform like Korea, appropriate resolution accuracy of source data are important factors to represent the topography concerned. In this study, the difference in contour interval of source data, the resolution after interpolation, and different data structures were compared to figure out the accuracy of slope calculation using DTM from the topographic maps of Togyusan National Park Two types of GIS softwares, Idrisi(grid) ver. 2.0 using the altitude matrices and ArcView(TIN) ver. 3.0a using TIN were used for this purpose. After the analysis the conclusions are as follows: 1) The coarser resolution, the more smoothing effect inrepresenting the topography. 2) The coarser resolution the more difference between the grid-based Idrisi and the TIN-based ArcView. 3) Based on the comparison analysis of error for 30 points from clustering, there is not much difference among 10, 20, 30 m resolution in TIM-based Airview ranging from 4.9 to 6.2n However, the coarser resolution the more error for elevation and slope in the grid-based Idrisi. ranging from 6.3 to 10.9m. 4) Both Idrisi and ArcView could net consider breaklines of lanform like hilltops, valley bottoms.

• Korean Journal of Environment and Ecology
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• v.2 no.1
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• pp.19-36
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• 1988

To investigate edge vegetation structure and edge species in Chiak Mountain National Park, field survey was executed from July to September, 1988. Canonpy drip-line type, cantilevered type and advancing type of edge vegetation were observed on site. The relative importance values of major species in each crown layer were changed along distance from edge to forest interior differently by aspect and present tree layer vegetation. Especially light-oriented edge species as codominant species were observed in Pinus densiflora forest interior at south slope and moisture - oriented species as codominant species were observed with light-oriented species in north edge beside torrential stream. No. of species and individuals by crown layer, species diversities and dissimilarities were decreased according to the distance from edge to forest interior, and edge depth was estimated as 15-20m. Dominant species of edge in shrub and ground layer were different by altitude and topographic locations; valley, ridge, summit and edge species at summit were not observed at other area. Floristic similarities between edge vegetations at different environments were affected by altitude, aspect and topographic location. Frequency classes of edge species were different by aspect, altitude and topographic location. Weigela subscssilis showed high frequency class in all environment conditions and Quercus mongolica, Lindera obtusiloba, Symplocos chinensis for, pilosa, weigela subscssilis, Fraxinus rhynchophylla, Actinidia arguta, Rubus crategifolius. Pinus densiflora, Aralia elata etc, were observed as edge species at all environmental conditions, respectively.

• Korean Journal of Environment and Ecology
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• v.2 no.1
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• pp.37-49
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• 1988

This study was conducted to investigate the user's effects on the avifauna in Chiak Mountain National Park. The survey was carried over 5 districts which were 3 main trail (valley) by line transect method from May to October 1988. The observed birds were 44 species and 613 individuals. these consist of 22 species for residents, 13 species for summer visitor, 5 species for winter visitor and 4 species for passage migrant. The average density of birds was 2.96 ea/ha, and main dominant species were Panus minar, Paradoxomis webbiana fulvicanda, Panus palustris hellmayri and Parus ater amurensis in order. The observed frequency of wild-birds was 6.77 times/km in average. No. of species, species diversities and observed frequency were lower in main trail of high user's density than sub trail and closed trail, especially in summer. But similarity indices were affected by inhabitation environments than user's density. Therefore, from now, in Chiak Mountain National Park management, the enjoyment oriented activities will be regulated and the control of trail use on main trail are necessary during breeding periods for wild birds protection.

• Korean Journal of Environment and Ecology
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• v.26 no.6
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• pp.934-940
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• 2012

This study was carried out to serve the structure of Carpinus laxiflora community in the Moojangsa valley, Tohamasan district, Gyeongju National Park. We designated 16 quadrats ($10m{\times}10m(100m^2)$) for looking at the continuation of Carpinus laxiflora community as the climax forest community. As a result of TWINSPAN, plant community was classified into 5 different communities. 3 communities are Carpinus laxiflora community which have a little different subdominant species; 1) with ombrophilous broadleaf species, 2) with Quercus serrata, 3) with others. Species diversity index was ranged from 0.4899 to 0.9490. Carpinus laxiflora communities were expected to continue as the Carpinus laxiflora community, but Carpinus laxiflora - Quercus serrata communities were expected continue or shrink up of the Carpinus laxiflora. As this study, if we insist the Carpinus laxiflora community as the climax in the temperate zone in Korea then should be analyze more survey data in various area.