• Journal of Korean Society of Forest Science
• /
• v.105 no.2
• /
• pp.167-176
• /
• 2016

This study was carried out to compare soil physicochemical properties and nutrient concentrations of tree leaf between planted forests following forest fire and an undisturbed forest in the Bongdaesan mountain, where is located in the Ulsan metropolitan city. We established three deciduous tree planting (Liriodendron tulipifera L., Prunus yedoensis Matsum and Quercus acutissima Carruth.) plots, one unplanted plot following four-year forest fire and one undisturbed plot (Pinus densiflora S et. Z). Carbon (C) stocks in the organic horizon were significantly lower in the tree planted plots ($2394-3551kg{\cdot}C{\cdot}ha^{-1}$) or the unplanted plots ($3689kg{\cdot}C{\cdot}ha^{-1}$) than in the undisturbed plot ($9388kg{\cdot}C{\cdot}ha^{-1}$). However, phosphorus (P), potassium (K) and magnesium (Mg) stocks in the organic horizon were not significantly different among the treatments. Soil water phase and soil pH were significantly higher in the P. yedoensis plot (water phase: 13.7-18.4%; soil pH: 4.62- 4.80) than in the undisturbed plots (water phase: 7.0%; soil pH: 4.10). Soil organic C concentration was slightly higher in the tree planted plots (1.89-3.60%) than in the unplanted (1.41%) plots. Soil Ca and Mg stocks at 10 cm of soil depth were significantly higher in the P. yedoensis and L. tulipifera plots than in the unplanted or undisturbed plots. Nutrient concentrations (Ca and Mg) of leaf were significantly higher in the L. tulipifera than in the Q. acutissima and the undisturbed pine plots. The results indicate that P, Ca, and Mg stocks in the organic horizon was not affected by tree planting, but Ca and Mg stocks at 10 cm of the soil depth were enhanced by the tree species established following four-year forest fire.

• Korean Journal of Environment and Ecology
• /
• v.30 no.2
• /
• pp.228-242
• /
• 2016

This research was conducted for understanding the evergreen forest community structure of the Bijin Island. The island was worth of vegetational value because of the representative warm temperate species such as Castanopsis cuspidata was distribute there. According to the results of community classification by TWINSPAN and DCA, the Bijin Island evergreen forest were classified by 9 communities, such as C. cuspidata, C. cuspidata-Pinus thunbergii, Neolitsea sericea-Camellia japonica, Platycarya strobilacea, Quercus serrata-Decidus broad-leaved, Alnus firma, P. thunbergii. Due to the C. cuspidata, N. sericea, Ca. japonica etc. were still dominated at canopy and under-canopy layer, so the evergreen forest will be sustain current conditions for a while if there is no artificial disturbances that were caused by human. Pl. strobilacea community will be expected to replace N. sericea and also Q. serrata-Decidus broad-leaved community will be changing caused by mutual competition. Normally, in the way of the succession process of the warm temperate forest, P. thunbergii will be expect via deciduous broad-leaved to evergreen forest such as Machilus thunbergii, C. cuspidata var. sieboldii, and N. sericea. In case of species diversity index, P. thunbergii comm.(1.2739), Q. serrata-Decidus broad-leaved comm.(1.2325), Decidus broad-leaved comm.(1.1807), and A. firma comm.(1.0854) are relatively high, while C. cuspidata and N. sericea-Ca. japonica that was dominated by evergreen species at canopy layer and P. thunbergii that was damaged by fire are relatively low(0.7380~0.8416). Soil pH was 4.72~6.33, electric conductance was 0.035~0.128dS/m, and content of organic matter was 3.4~17.4%.

• Journal of Korean Society of Forest Science
• /
• v.110 no.3
• /
• pp.419-430
• /
• 2021

This study investigated spatiotemporal trends of sediment-related disasters in North Korea from 1960 to 2019 and post-disaster recovery cases based on a literature review and satellite images. Results showed that occurrence status of sediment-related disasters was initially externally reported in 1995 (during the Kim Jongil era); their main triggering factor was heavy summer rainfall. Furthermore, forest degradation rate was positively correlated with population density (R² = 0.4347, p = 0.02) and occurrence number of sediment-related disasters was relatively high on the west coast region, where both variables showed high values. This indicates that human activity was a major cause of forest degradation and thus, significantly affected sediment-related disasters in mountain regions. Finally, sediment- related disasters due to shallow landslides, debris flow, and slow-moving landslides were observed in undisturbed forest regions and human-impacted forest regions, including terraced fields, opencast mines, forest roads, and post-wildfire areas, via satellite image analysis. These disaster-hit areas remained mostly abandoned without any recovery works, whereas hillside erosion control work (e.g., treeplanting with terracing) or torrent erosion control work (e.g., check dam, debris flow guide bank) were implemented in certain areas. These findings can provide reference information to expand inter-Korean exchange and cooperation in forest rehabilitation and erosion control works of North Korea.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.27 no.3
• /
• pp.1-18
• /
• 2024

The study aims to establish a direction for forest ecological restoration by classifying forest types and understanding the ecological characteristics of the Uljin forest area damaged by a large fire in 2022. Hierarchical cluster analysis and indicator species analysis were conducted on 78 survey plots located in the forest fire-affected area, and four forest cover types were derived: P. densiflora pure forests, P. densiflora dominant forests, mixed broad-leaved forests, and Q. variabilis dominant forests. As a result of visually comparing changes in forest types before and after forest fire damage, by classifying data according to whether or not upper dead trees are included, it was confirmed that pine forests, which have a high proportion of pine trees, spread widely due to forest fire damage. However, broad-leaved mixed forests and oyster oak dominant forests showed characteristics of maintaining concentration, indicating that pine forests were severely damaged. As a result of the important value analysis, during the process of natural recovery after a forest fire, the species that appear early in the lower layer are the sprouts of existing species such as Quercus mongolica Fisch. ex Ledeb., Quercus variabilis Blume, Fraxinus sieboldiana Blume, Rhododendron mucronulatum Turcz. The distribution of diameter at breast height by forest cover type showed that among areas with extreme forest fire damage, the proportion of dead trees was relatively high and structural changes were large in P. densiflora pure forests and P. densiflora dominant forests where pine trees had a high distribution ratio. However, if continuous monitoring is carried out in the future with reference to the results of this study and plant data is collected and analyzed from a mid- to long-term perspective, it is believed that it will be used as useful data to promote forest ecological restoration projects in forest fire-affected areas.