• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.3
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• pp.103-111
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• 2016

Seasonal dynamics of kelp forest-forming algae, Ecklonia cava population formed following the large-scale disturbance by Typhoon 'Bolaven' in August 2012 were investigated in Jeju Island, Korea. Morphological characteristics, recruits density, mortality rate, total density and biomass were monitored bimonthly from June 2013 to June 2015. Total and longest blade lengths, and individual weight of E. cava showed distinct seasonal trends. Stipe length increased from winter to spring, but did not show increase or reduced from summer to autumn. This indicates that morphological characteristics of E. cava are mainly affected by the change of blades. The optimal temperature for E. cava growth was about $15-18^{\circ}C$ during winter to spring while the growths were inhibited at the water temperature above $20^{\circ}C$ during summer. E. cava exhibited very low recruitment during spring-summer. However, high recruitment was observed on April 2015 when canopy cover was very low due to low density. This indicates that recruitment of E. cava was controlled not by seasonal effects but by physical factors such as canopy and space. The mortality rate of juvenile plants was highest due to their unstable settlement. By June 2015, 34 months after the disturbances, E. cava was almost recovered to the pre-disturbance population size structure. These results suggest that recovery of kelp forest following the large-scale disturbance requires a considerable period of time (more than three years). This study should provide valuable ecological information on management, restoration and protection of kelp species.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.4
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• pp.197-202
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• 2002

A new method is used to estimate the amount of water evaporation from Class A Pan with higher precision and accuracy. The principle of method is to detect the weight change of a buoyant sinker resulting from a change in water level of Class A Pan. A strain-gauge load cell is used to measure the weight change. Field observation of evaporation was done at Pohang Meteorological Station from June 24 to August 4, 2002. By using this new method, it is possible to measure hourly evaporation accurately even under a strong solar radiation and wind disturbance, enabling a direct comparison of evaporation with other meteorological elements. At night, under low humidity and high wind speed conditions, more evaporation was recorded than during daytime. Maximum evaporation rates observed during this period exceed 1.0 mm/hour under the sunny and windy conditions with low humidity. To understand relationships between meteorological elements and latent heat flux at ground level, we suggest intensive held experiments using high accuracy evaporation recording instruments with hourly time interval.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.255-261
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• 2003

To analyze ecological characteristics of the Ulmus pumila community, an on-the-spot survey was conducted in August, 1998 in the Dong River, Gangwon-do, South Korea. The Ulmus pumila community is partially distributed in Dong River's midstream and upper stream. Topographical characteristics of this community are significant in the point bar or sandbank of the river. The community is classified into two types, disturbed and non-disturbed types, by the effect of flooding. The Ulmus pumila community (bush forests of Siberian elms) is a representative community which forms riparian forests, but its distribution is rare in South Korea. Only in Dong River is the Ulmus pumila distributed enough to form a community, and none is known that is lager than this community in South Korea. The non-disturbance type progresses more homogeneously than the disturbance type because it is formed on riverside banks where it is affected less by flooding. We concluded that the Ulmus pumila community in this study area has characteristics of riparian forests. In South Korea, Ulmus pumila community can be regarded as important element of vegetation landscape constituting riparian forests. Specifically, these riparian forests are evaluated as high in conservation value due to their being formed spontaneously. Moreover, Dong River is regarded as the southern limit of Ulmus pumila, which has a northern origin. The species or community needs continuous interests and conservation countermeasures because there are limitations in its spread of distribution by natural or artificial efforts.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.190-200
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• 2022

In this study, the island's land-use and land-cover change (LULCC) is analyzed in South Korea using remotely sensed land cover data(Globeland 30) acquired from 2000 to 2020 to meet the requirement of providing practical information for forest management. Analysis of LULCC between the 2000 and 2020 images revealed that changes to agricultural land were the most common type of change (7.6% of pixels), followed by changes to the forest (5.7%). The islands forests maintain 157,246 ha (42.2% of the total island area). Land cover types that changed to the forest from grasslands were 262 islands, while reverse cases have occurred on 421 islands. These 683 islands have a possibility of transition and disturbance. The artificial land class was newly calculated in 22 islands. The forests, which account for 42.2% of the 22 island area, turned into grassland, and 27.8% of agricultural land and grassland turned into forests. The development of artificial land often affects developed areas and surrounding areas, resulting in deforestation, management of agriculture, and landscaping. This study can provide insights concerning the fundamental data for assessing ecological functions and constructing forest management plans in islands ecosystems.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.355-364
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• 2013

This study was conducted to investigate the population structure and dynamics of the Picea jezoensis stands which are located in Mt. Gyebangsan and surveyed from March to October 2012. Results showed that the diameter class distribution of P. jezoensis presented a reverse J-shaped distribution pattern with 32 trees less than 10 cm DBH, 20 trees in 10~30 cm DBH, and 11 trees more than 30 cm DBH. It showed seedlings and saplings of P. jezoensis seem to prefer areas with more sun light or with open upper layer. It was also observed that P. jezoensis preferes areas with organic soils and abundant water such as areas around stumps. Also, occurrences of P. jezoensis stands were analyzed through annual mean radial growth of the trees. And the results showed that the growth naturally or artificially occurred approximately on the years 1854, 1915, 1918, 1993 and 2002 years. Most of the gap-makers were classified as standing dead type with 23 individuals (45.1%).

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.62-70
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• 2014

The principle purpose of this research is to figure out whether the inhalation of Wood Essential oil (Chamaecyparis obtusa) affect not only human beings' concentration for surroundings but also change as to status of feelings. total number of subjects for this experimental are determined to be 66 (men 44 and women 22) among 85 adults who agreed to participate in this experiment after excluding 19 participants who were not able to smell scent due to flu and nasal inflammation. After both experimental group and control group being measured referring to their status of mood such as concentration, depression, vigor, fatigue, confusion, tension and anger, the experimental group is offered to get a piece of cotton that includes Wood Essential oil and they are asked to inhale it for 5 min. On the other hand, control group is offered to wait for the experimental group finishing inhaling wood Essential oil for 5 min. After 5 min, the status of mood from both groups were measured again. simultaneously, I conducted a survey targeting experimental group to see what their preferences are like regarding scent of wood essential oil. The experiment shows that the status of experimental group's concentration is improved about 0.94 point when compared to control group's. Moreover, Total mood disturbance is lower than control group's. Therefore it is proved that the inhalation of wood Essential oil alleviates overall status of mood. according to the analyses result of favor to scent for wood essential oil from experimental group, some of them who were positive got much better improvement when it comes to concentration and far more relieved on their feelings than those who weren't. Based from this result, it is definitely confirmed that there is a Phytoncide's psychophysiological effect which transcends the Placebo Effect generated by Phytoncide's positive image.

• The Korean Journal of Mycology
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• v.42 no.2
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• pp.133-137
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• 2014

This study was conducted to investigate the effect of thinning on ectomycorrhizal fungal communities in a forest. Ectomycorrhizal root tips were collected from forest soils in thinning and non-thinning sites and identified using morphological characteristics and molecular analysis of ITS rDNA sequences. As a result, species richness of ectomycorrhizal fungi was significantly increased and ectomycorrhizal fungal community composition was changed by thinning. These results suggest that forest management such as thinning, could be an important factor affecting mutualistic relationships and belowground microorganisms in forest ecosystems.

• Journal of Ecology and Environment
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• v.43 no.4
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• pp.364-375
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• 2019

Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.61-67
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• 2015

This study, which was conducted from Apr. 2013 to Jan. 2014, was carried out as part of a project of making a more detailed ecological zoning map with 1/5,000 scale. The necessity of electronic vegetation map with large scale has arisen in order to make the best use of basic research findings on resource monitoring of National Parks and to enhance efficiency in National Park management. In order to improve accuracy and speed of vegetation research process, the data base for vegetation research was categorized into five groups, namely broad-leaved forest, coniferous forest, mixed forest, rock vegetation and miscellaneous one. And then a vegetation map for vegetation research was created for the research on the site. What is in the database for vegetation research and the vegetation map reflecting findings from vegetation research showed similar distribution rate for broad-leaved forest with 71.965% and 71.184%, respectively. The distribution rate of coniferous forest (16.010%, 15.747%), mixed forest (10.619%, 12.085%), and rock vegetation (0.015%, 0.002%) did not have much difference. In a detailed vegetation map reflecting vegetation research findings, the broad-leaved mountain forest was the most widely distributed with 60.096% based on the physiognomy classification. It was followed by mountain coniferous forest (16.332%), mountain valley forest (15.887%), and plantation forest (3.558%) As for vegetation conservation classification evaluated in the national park, grade I and grade II areas took up 200.44 km2, 61.80% and 108.80 km2, 33.55% respectively. The combined area of these two amounts to 95.35%, making this area the first grade area in ecological nature status. This means that this area is highly worth preserving its vegetation. The high rate of grade I area such as climax forests, unique vegetation, and subalpine vegetation seems to be attributable to diverse innate characteristics of Odaesan National Park, high altitude, low level of artificial disturbance, the subalpine zone formed on the ridge of the mountain top, and their vegetation formation, which reflects climatic and geological characteristics, despite continuous disturbance by mountain climbing.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.79-85
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• 2000

Mortality patterns ad changes of vegetation in newly formed gaps were investigated to examine the succession process of Pinus densiflora forest located at Mt. Worak. The main findings from this study were as follows: ⑴ The forest was dominated by P. densiflora and Quercus variabilis in the oversotry, while Q. mongolica, Q. serrata and Fraxinus sieboldiana in the mid-story. ⑵ In all study areas, the standing dead type was the most common factor influencing gap-forming mortality. ⑶ DBH analysis showed that Pinus densiflora community was replaced by Quercus variabilis community first, and then by quercus mongolica and quercus serrata community. ⑷ Seedlings of P. densiflora were discovered only at dry sites of the gap.