• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.1
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• pp.10-14
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• 2006

We tested the seed viability of Pinus rigida using accelerated aging to discover optimum times and temperatures far artificially accelerated aging. Seeds were artificially aged at different temperatures and during different tines. The seed viability was affected by the accelerated aging and by temperature with a decline in germination and seed vigor. The aging index of P. rigida seed was 0.31 at $35^{\circ}C$ and seed viability was nearly lost after aging treatment at $40^{\circ}C$ for 15 days. The optimum temperature of P. rigida far the aging test was decided to be approximately $37^{\circ}C$ on the basis of the aging index. Inorganic materials and conductivity of leaching solution from aging seeds increased with the increase of aging period. The accelerated aging test was considered to be a suitable method to evaluate the seed viability of tree species. Because seed characters are much different among tree species, however, more studies need to be done to discover the optimum conditions for aging by tree species.

• Korean journal of applied entomology
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• v.21 no.4 s.53
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• pp.195-199
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• 1982

Data on population density of the pine moth, Dendrolimus spectabilis Butler, were collected in October at 9 permanent study plots for 13 years $(1968\~1980)$ and graphically analysed. Population density sowed peaks in 1970 and 1975 year and declines in 1972 and 1976 year, and similar trends have been observed over the country. Rainfall, particularly the maximum rainfall per day, in August seems to be a key factor resulting in the sudden decline in density and this could explain almost synchronous fluctuation. The intensity of rainfall in August affecting the decline if density was estimated to be more than 100mm per day.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.551-571
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• 2022

Xylella fastidiosa is xylem-limited bacterium capable of infecting a wide range of host plants, resulting in Pierce's disease in grapevine, citrus variegated chlorosis, olive quick decline syndrome, peach phony disease, plum leaf scald, alfalfa dwarf, margin necrosis and leaf scorch affecting oleander, coffee, almond, pecan, mulberry, red maple, oak, and other types of cultivated and ornamental plants and forest trees. In the European Union, X. fastidiosa is listed as a quarantine organism. Since its first outbreak in the Apulia region of southern Italy in 2013 where it caused devastating disease on Olea europaea (called olive leaf scorch and quick decline), X. fastidiosa continued to spread and successfully established in some European countries (Corsica and PACA in France, Balearic Islands, Madrid and Comunitat Valenciana in Spain, and Porto in Portugal). The most recent data for Europe indicates that X. fastidiosa is present on 174 hosts, 25 of which were newly identified in 2021 (with further five hosts discovered in other parts of the world in the same year). From the six reported subspecies of X. fastidiosa worldwide, four have been recorded in European countries (fastidiosa, multiplex, pauca, and sandyi). Currently confirmed X. fastidiosa vector species are Philaenus spumarius, Neophilaenus campestris, and Philaenus italosignus, whereby only P. spumarius (which has been identified as the key vector in Apulia, Italy) is also present in Americas. X. fastidiosa control is currently based on pathogen-free propagation plant material, eradication, territory demarcation, and vector control, as well as use of resistant plant cultivars and bactericidal treatments.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.62-68
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• 2012

We have investigated needle life span, photosynthetic pigment and nitrogen allocation pattern in the needle of Picea jezoensis in the three populations (Gyebangsan, Deogyusan and Jirisan) to find out growth environmental condition which needs the strategy development of conservation and restoration against population decline. Needle survival rate was the highest in Gyebangsan (87.0%) and the lowest in Jirisan (71.6%), and it decreased with the increase of needle age. Needle chlorophyll a and b in Deogyusan and Jirisan showed higher content in older needle, but chlorophyll content in Gyebangsan was the highest in 2-year-old needle. Carotenoid content was the highest in the needle in Gyebangsan, and it increased along with needle age. Chlorophyll a/b ratio showed the highest value in Jirisan and the lowest value in Gyebangsan. Chlorophyll/carotenoid ratio decreased with needle age, Needle nitrogen content was the highest in Deogyusan (1.51%) and the lowest in Gyebangsan (1.40%), and the older needle had the lower content. In contrast, the highest chlorophyll/nitrogen ratio represented the oldest needle.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.133-138
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• 2001

Increased base cation loss and Al mobilization, a consequence of soil acid neutralization responses, are common in air polluted areas showing forest decline. The prediction models of acid neutralization responses were developed by using indicators of soil acidification level(pH, and base saturation) in order to assess the forest soil sensitivity to acidification. The soil acidification level was greatest in Namsan followed by Kanghwa, Ulsan, and Hongcheon, being contrary to regional total $ANC_H$ pattern through soil columns leached with additional acid ($16.7mmol_c\;H^+/kg$), Both base exchange and Al dissolution were main acid neutralization processes in all study regions. There were low base exchange and high Al dissolution in the regions of the low total $ANC_H$. The $ANC_M$ by sulfate adsorption was greatest in Hongcheon compared with other regions even though the AN rate was very low as 6.4%. Coefficients of adjusted determination of simple and multiple regression models between soil acidification level indicators and the acid neutralization responses were more than 0.52(p<0.04) and 0.89(p<0.01), respectively. The result suggests that soil pH and base saturation are available indicators for predicting the acid neutralization responses. These prediction models could be used as an useful method to measure forest soil sensitivity to acidification.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.21-30
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• 2012

The objective of this study was to comprehend inter-species association and factors affecting species composition by factor analysis and to classify forest types of natural forests in Dootasan. We examined the correlation (positive or negative) of the major species by correlation analysis, the selection of three factors affecting the species composition by factor analysis, cluster analysis on the basis of factor scores, and the evaluation of the results of forest type classification by ANOVA. The outputs of correlation analysis were closely associated with those of factor analysis. The first factor affecting species composition was found to be the decline phenomenon of Pinus densiflora during forest succession process. The second and third factors were growth environments in valley and slope, respectively. The cluster analysis was carried out based on three factors affecting the species composition. The results indicated that the study area was classified into four forest types as follows: Quercus mogolica-Acer mono-Fraxinus rhynchophylla community, Q. mongolica community, Q. mongolica-Tilia amunrensis community and Pinus densiflora community. The dominant species of each community in the four classified forest types were significantly different (p<0.05).

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.550-559
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• 2013

This study looked over the laws and regulations related to forestry workers to analyze the safety accident rates for the past five years (2006-2010), and to suggest improvement plans to reduce the safety accident rates of forestry workers. Findings from comparing information obtained from data are outlined below. The safety accident rates had gradually increased in the forestry fields until 2010, but nowaday it is on the decline. Furthermore, the safety accident rates in the field of forestry were still serious compared to those in the other industrial fields as from 2.1 to 5.1 times. In the results, the workers were especially vulnerable to safety accidents when they fell under the following categories: when falling; within 29 to 90 days after starting the work; over 60 years old; less than one month of service; October; Wednesday; 11 a.m.; and the nether limbs of the body. In the case of Jeollabuk-do, it was reported that more than half of victims did not have any training in safety.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.153-163
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• 2024

Since the onset of the COVID-19 pandemic, there has been a significant shift in the lifestyle patterns of the populace across various domains. Concerns surrounding COVID-19 have emerged as pivotal catalysts of change in recreational habits with people giving a particular preference for environments with low population density and increased openness. This trend has resulted in an uptick in excursions to natural reserves, coastlines, and parks. However, during the peak of infectious outbreaks, widespread adherence to social distancing measures has precipitated a steep decline in tourist footfall across natural recreation forests, exacerbating financial deficits to a considerable extent. Thus, this research sought to compare and analyze the operational efficacy and productivity of national, public, and private natural recreation forests pre- and post-COVID-19 pandemic by utilizing non-parametric methodologies, such as data envelopment analysis and the Malmquist productivity index analysis. The objective was to identify the factors contributing to the decreases in efficiency and productivity and ultimately offer nuanced recommendations tailored to respective administrative bodies. This study's distinctive focus on the analysis of management efficiency and productivity in natural recreation forests nationwide offers significant academic and practical relevance.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.1
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• pp.121-133
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• 2016

It was required to evaluate ecological restorations in a comprehensive way in order to systematically manage conservation areas such as DMZ and national parks in South Korea. In this research we developed a new approach to evaluating ecological restorations with more various indexes than vegetation covering-related indexes. By analyzing damaged areas in the vicinity of DMZ, major damaged types were identified as six classes: landform modification, surface loss, soil pollution, soil physio-chemical modification, vegetation decline and vegetation damaged. From literature review, 39 indexes were selected and were grouped into four divisions: soil property, vegetation growth & structure, habitat property and landscape structure & functions. By conducting a survey with the selected indexes targeting relevant experts, data on relative importance among the divisions and indexes by damaged type were collected. As a result, it was found that the orders and values of weighted values of the divisions were different by damaged type: for example, soil property (0.402), vegetation growth & structure (0.209), habitat property (0.225), landscape structure & function (0.163) for "landform modification"; but soil property (0.171), vegetation growth & structure (0.401), habitat property (0.270), landscape structure & function (0.158) for "vegetation decline". Similarly, evaluation indexes showed different orders and values of relative importance, easiness in field measurement and representativeness for the division by damaged type, and the values were used for calculating importance factor for each index. In the evaluation table, score1 and score2 were made by the importance factors of indexes multiplied by distribution values which present grades and by the weighted values of divisions. In conclusion, while dealing with the damaged type was considered significant for evaluating and managing restorations, further tests on this table with a range of cases were needed to improve its quality.

• Journal of Plant Biology
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• v.25 no.1
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• pp.37-53
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• 1982

Pollen analysis from lake districts, Youngnangho, Wolhamji and Bangeojin, revealed vegetational patterns in Korea. The pollen stratigraphy was divided into five zones, zone L, I, II, IIIa and IIIb for the past 15,000 years. During zone L (earlier than 10,500 yr BP), late-glacial period, Youngnangho was vegetated with a coniferous forest dominated by spruce, larch, haploxylon pine and fir with considerable amount of herbs. Zone I(10,500~7500 yr BP) was predominantly herbaceous vegetationj with significant amount of oak and diploxylon pine. It suggests that the overall environment became milder and drier than late-glacial period. Zone II(7,500~4,000 yr BP), hypsithermal period, showed significant warming condition, indicated by high pollen concentrations of oak, diploxylon pine and hornbeam, and by more diverse flora of deciduous broad-leaved trees than before. Herbs were not an important part of vegetation. Zone III$^a$(4,000~1,500 yr BP) had pine and oak as main elements. Birch increased slightly while hornbeam decreased in this time. It indicates cooling condition. Zone III$^b$(1,5000-present) which can be called pine period showed obvious human interference. Following forest clearance, agriculture was intensified. The beginning of logging and agriculture was discernible by a sudden decline of arboreal species and by considerable amount of rice, buckwheat, sorrel and plantain. Numerous charcoal fragments were observed in zone I and zone III$^b$.