• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.309-319
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• 2002

Soil adsorption study was carried out to define the mobility of pesticides or to evaluate leaching potential in soils. Five pesticides including ethoprophos, procymidone, iprobenfos, isoprothiolane, and butachlor were subjected to optimized adsorption experiment protocol for three types of cultivation soils. Freundlich adsorption coefficients (K) were ranged $0.35{\sim}0.95$ for ethoprophos, $0.98{\sim}2.2$ for iprobenfos, $1.2{\sim}4.3$ for procymidone, $1.5{\sim}3.5$ for isoprothiolane and $7.9{\sim}19$ for butachlor in three soils. Based on Koc values, ethoprophos was classified as mobile, iprobenfos, isoprothiolane and procymidone as moderately mobile and butachlor as slightly mobile. Two evaluation methods, Groundwater Ubiquity Score (GUS) index and standard indices of soil-chemical adsorption and biodegradation, were used for the estimation of pesticide leaching potential. Leachability of isoprothiolane and iprobenfos were evaluated as moderate, ethoprophos as a little potential, while butachlor and procymidone showed very low leaching potential. The leaching potential of pesticides was essentially determined on the basis of intrinsic properties of the pesticides and environmental properties. Among the soil properties, organic matter gave a great influence on the leachability of soils. Therefore, leachabilities of pesticides were expected less in loam with relatively higher organic matter than clay loam with lower organic matter.

• Korean Journal of Environment and Ecology
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• v.14 no.1
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• pp.38-45
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• 2000

This research has been done to investigate influence of soil physical and chemical properties on forest environmental change by fired pine forest in Koseong, Kangwondo. The sample sites were divided by not-fired sites(NF), not-cutting site after fired(FNC), cutting and planting sites after fired(FCP) and cutting and not-planting sites after fired(FC). Soil texture of whole sites was sandy clay loam. Sand content of NF top soil were lower than those of sub soil and clay content were higher, while FNC, FCP and FC sand content of top soil were higher than those of sub soil. Total porosity didn't differ between the sites. Coarse porosity and permeability had the increasing order as NF> FNC> FCP> FC, but fine porosity and bulk density had the opposite trends. Because forest fire removed the vegetation and then soil erosion was accelerated, forest environmental changes by forest fire greatly degraded soil porosity and permeability which were indices for forest water retention, so that soil physical properties were deteriorated. Both top and sub soil pHs of NF and FNC were higher than those of FCP and FC. Organic matter content and total nitrogen content of top and sub soils were high in order as NF> FNC> FCP> FC. Cation exchange capacities and exchangeable cation(K+, Na+, $Ca^2$+, $Mg^2$+) content in top soils were higher than those in sub soils, and in order as NF> FNC> FCP> FC, to be compared by the sites. Those mean that forest fire result from the erosion of top soil layers.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.33-48
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• 2009

Forests store carbon dioxide ($CO_2$), one of the major factors of global warming, in vegetation and soils through photosynthesis process. In addition, woods deposit $CO_2$ for a long term until the harvested wood is decomposed or burned, and deforested areas could be expanded the carbon sinks through reforestation. Forests are a lso able to decrease temperature through transpiration and contribute to control the micro climate in global climate systems. Consequently, forests are considered as one of major sinks of greenhouse gases for mitigating global warming. It is very important to develop a Korea specific forest carbon flux model for preparing adaptation measures to climate change. In this study, we compared the climate change impact models in forests developed in foreign countries and analyzed the applicability of the models to Korean forest. Also we selected models applicable to Korean forest and suggested approaches for developing Korean specific model.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.83-90
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• 2012

This study was undertaken to analyze 1) the growth characteristics for the optimal planting density and 2) reached ages of sap tapping for the planting timing of Acer okamotoanum in natural and plantation stand. Soil in natural stand was significantly more fertile than that of plantation stand. Early growth of A. okamotoanum in plantation stand was affected by planting density. Results showed that there was a positive relationship between the DBH and crown width in both natural and plantation stands. Reached ages by DBH were no significant difference in natural stands. Reached ages on DBH 10 cm were approximately 19 and 9 in natural and plantation stands, respectively.

• Journal of Korea Water Resources Association
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• v.50 no.10
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• pp.653-660
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• 2017

The SCS-CN (Soil Conservation Service-Curve Number) method has been practically applied for estimating the effective precipitation. The CN is used to be determined according to the land use condition based on the US standard. However, there are two distinctive differences between U.S. and Korean land use conditions: mountainous (forest) and rice paddy area that cover more than 70% of the Korean territory. The previous work proposed to use 79 for rice paddy area, regardless of the soil type. Because US SCS's goal was originally to increase crops, the SCS classification standard provides only for woods and there are no criteria to distinguish the wood and forest. To determine the CN for forest, alternatively the U.S. Forest Service criteria have been employed in practice considering hydrologic condition class. In this study, we investigated the change of the forest CN using the observed rainfall - runoff data within the target area. The results indicated that the CN for forest was suitable for HC=1, and the corresponding CNs were redetermined between 54 and 55.

• Journal of Korean Society of Forest Science
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• v.89 no.2
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• pp.185-197
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• 2000

This study was carried out to research structure of forest vegetation and site condition, and supply basic data for conservation of pine forest and ecologically sustainable forest management and control in Anmyondo area. The forest of Anmyondo were largely classified as four forest community : Pinus densiflora community, Pinus thunbergii community, Pinus rigida community, and Quercus variabilis community. Organic matter, total nitrogen, and other nutrients in soil of the study area were relatively low, and average soil pH was 4.9. Soil texture was sandy clay or heavy clay and so the aeration and permeability could be poor. In this study site, the methods such as the promotion of germination of pine seeds through removal of forest floor and inducement of natural regeneration through such method as regeneration under shelter wood would be better than the method such as afforestation after clear-cutting for conservation the pine forests. Also, it will be a good method to practice tending for hardwood species in the dominant areas by hardwood species.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.1-8
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• 2009

The limestone area covers the narrow range of the Korean Peninsula, and it consists of a peculiar ecosystem and topography. Therefore, this study on limestone area was carried out classification of vegetation type, physicochemical properties of forest soils and correlation between environment factors and vegetation types in order to furnish fundamental data for the forest management of limestone area. Forest vegetation was classified into two community groups such as Quercus variabilis community group and Quercus mongolica community group, and it was classified into eight vegetation units. Soil texture of survey sites showed largely silt loam and soil pH indicated the value of mean 7.55 in the A layer of soil profile. Content of exchangeable cation such as calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) showed $26.04cmol_{c}/kg$ and $2.93cmol_{c}/kg$, respectively, which was about ten times higher than average of other regions of Korea. According to corelation between environmental factors and vegetation units, Q. variabilis community group was positively correlated to soil pH, slope degree and the rate of bare rock, and content of calcium ion ($Ca^{2+}$), and then Q. mongolica community group was positively correlated to altitude, respectively.

• Journal of agriculture & life science
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• v.45 no.5
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• pp.17-23
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• 2011

Growth characteristics and adaptability of 10 poplar clones planted at a reclaimed tidal flat were evaluated. The contents of $Na^+$, $Ca^{2+}$ and $Mg^{2+}$ were 10.0, 3.4 and 1.5 times higher, respectively than those of control although the electrical conductivity(EC) in the soil at the test plantation was low as much as 0.51 dS/m. The contents of organic matter(OM) and total nitrogen(TN) in the soil were 22.9 and 23.0 times lower than those of control. Average survival rate of 10 poplar clones showed 88% at three years after planting. Clones Eco28(Populus euramericana), Dorskamp(Populus deltoides ${\times}$ P. nigra) and I-476(Populus euramericana) showed the best survival rate of 100%. However, clones 97-19(Populus deltoides(Lux) ${\times}$ P. deltoides(Harvard)) and Suwon (Populus koreana ${\times}$ P. nigra var. italica) were relatively lower than other clones. Average height and DBH of all clones were 4.8 m and 3.6 cm, respectively. Clone Dorskamp showed the greatest height and DBH, 5.9 m and 5.0 cm, respectively. Clones 97-19 and Dorskamp showed the least defoliation by stress and visible damage by insects and diseases, whereas clones Suwon and I-476 were the most sensitive at the reclaimed tidal flat. Clone Dorskamp showed the best adaptability at the reclaimed tidal flat, but clone Suwon showed the worst based on survival rate, growth, and visible damages.

• 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).

• Journal of Wetlands Research
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• v.25 no.4
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• pp.417-425
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• 2023

As climate change gets severe, the ecosystem acts as an important carbon sink, therefore efforts are being made to utilize these functions to mitigate climate change. In this study, we inventoried and analyzed the previous studies related to carbon storage and flux by ecosystem type (forest, cropland, wetland, grassland, and settlement) and carbon pool (aboveground and belowground biomass, dead wood, Litter, soil organic carbon, and ecosystem) in Korean ecosystems. We also collected the results of previous studies and calculated the average value of carbon storage and flux for each ecosystem type and carbon pool. As a result, we found that most (66%) of Korea's carbon storage and fluxes studies were conducted in forests. Based on the results of forest studies, we estimated the storage by carbon stock. We found that much carbon is stored in vegetation (aboveground: 4,018.32 gC m^-2 and belowground biomass: 4,095.63 gC m^-2) and soil (4,159.43 gC m^-2). In particular, a large amount of carbon is stored in the forest understory. For other ecosystem types, it was impossible to determine each carbon pool's storage and flux due to data limitations. However, in the case of soil organic carbon storage, the data for forests and grasslands were comparable, showing that both ecosystems store relatively similar amounts of carbon (4,159.43 gC m^-2, 4,023.23 gC m^-2, respectively). This study confirms the need to study carbon in rather diverse ecosystem types.