• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.23-35
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• 2010

For the sustainable conservation of forests within and around the somma of Nari basin in Ulleung Island, the stand structure and dynamics with the aspect, altitude and stand types were estimated by using analyses of importance value, plant species diversity, S$\o$rensen's similarity index and distributions of diameter classes. Results of the importance value analysis with vegetation stories on each stand showed that Fagus engleriana and Acer okamotoanum were dominant in most stands regardless of the aspect and altitude of the forest around the somma of Nari basin and the plant species composition among stands was not significantly different. The forest within Nari basin was composed of pine, beech, alder and deciduous-mixed stand. Moreover, the species composition was greatly different among the four stands. The diversity of plant species within stand was in general higher within Nari basin than around the somma, and among stands within Nari basin, the plant species diversity of pine and deciduous-mixed stand showed higher values than that of beech and alder stands. The similarity index among stands with aspect and altitude showed that the index among stands of eastern, western and northern slope in forest around the somma and forest within the basin ranged from 0.68 to 0.69, and the similarity among four stands with altitude was very high having index range from 0.85 to 0.95. The patterns of diameter class distribution of the major dominant species from four altitude classes followed an almost normal bell-shaped distribution. The results were interpreted as an indication that these forests will in general maintain a stable stand structure. Therefore, despite diverse topographic features around Nari basin, the stand structure and plant species composition among stands were not diversified as expected. For the conservation of diversity of forest plant species and of forest ecosystems, a promising and intensive program should be considered.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.577-589
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• 2021

Soil seed bank community contributes to the long-term conservation of plant diversity and vegetation dynamics, and their decreasing diversity and density with soil depth provide critical perspectives (deterministic and stochastic) for understanding the community disassembly process. We analyzed changes in species composition and diversity and structuring patterns by soil layer (top and bottom), including surface vegetation, in Gwangneung Forest, a mature forest with a vegetation climate in the temperate central part of the Korean Peninsula. From two layers of soil collected with a vertical difference of 10 cm, 934 specimens of 27 families, 40 genera, 44 species, three varieties, and 47 taxa, germinated. Although species diversity and germination density decreased in most comparative characteristics, including growth type, there was no statistical significance due to large deviations. Within-group variability of species composition was similar in the upper and lower soils, as was the decline pattern in co-occurred species (ζ-diversity) and change in species retention probability. The structuring process of the community composition in the two soil layers was fitted with an exponential correlation rather than a power function, demonstrating the dominance of the stochastic process. The pattern in diversity and species turnover according to soil depth in Gwangneung Forest was discovered to be structured by stochastic random events, such as seed vertical movement rather than interaction with trait characteristics.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.563-575
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• 2022

Maruca vitrata is one of important pests in leguminous crops, especially red bean. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. vitrata for understanding the biological characteristics of the insect species at eight constant temperatures of 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected and larvae successfully developed to the adult stage from 16℃ to 31℃. The developmental period of egg decreased up to 31℃ and after then increased. The developmental period of larva and pupa, and adult longevity of M. vitrata decreased with increasing temperature. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. vitrata were estimated by linear regression as 12.8℃ and 280.8DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 14.2℃ and 31.9℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. vitrata was 17.7℃. In addition, we constructed the oviposition models of adult, using the investigated adult traits including survival, longevity, oviposition period and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M vitrata and to establish the strategy of integrated pest management in legume crops.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.577-590
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• 2022

Ostrinia scapulalis is one of important pests in leguminous crops, especially red bean. In order to understand the biological characteristics of the insect, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of O. scapulalis at eleven constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, 34, and 36℃. Eggs and larvae successfully developed next life stage at most temperature subjected except 7, 10 and 13℃. The developmental period of egg, larva and pupa decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of O. scapulalis were estimated by linear regression as 13.5℃ and 384.5DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 19.4℃ and 39.8℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of O. scapulalis was 20.4℃. Adults produced viable eggs at the temperature range between 16℃ and 34℃, and showed a maximum number, ca. 416 offsprings, at 25℃. Adult models including aging rate, age-specific survival rate, age-specific cumulative oviposition, and temperature-dependent fecundity were constructed, using the temperature-dependent adult traits. Temperature-dependent development models and adult oviposition models will be useful components to understand the population dynamics of O. scapulalis and will be expected using a basic data for establishing the strategy of integrated pest management in leguminous crops.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.461-473
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• 2022

Matsumuraeses phaseoli is one of important pests in soybean crops, especially adzuki beans. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. phaseoli for understanding the biological characteristics of M. phaseoli at ten constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected except 7℃ and 34℃. The developmental period of each life stage and adult longevity of M. phaseoli decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. phaseoli were estimated by linear regression as 9.04℃ and 422.97DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 20.0℃ and 32.3℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. phaseoli was 12.3℃. We constructed the adult oviposition model of M. phaseoli using adult survivorship and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M. falcana and to establish the strategy of integrated pest management in soybean fields.

• Korean Journal of Environment and Ecology
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• v.32 no.3
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• pp.313-322
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• 2018

To investigate the changing patterns of sub-alpine forest vegetation due to climate change requires accumulation of contiguous reference data and continuous monitoring. Furthermore, it is crucial to monitor short-term ecological change of lower level vegetation to understand the trend of long-term vegetation change. Therefore, this study carried out a vegetation survey and tree diameter measurement in 36 plots of Mt. Jiri inhabited by Abies koreana species from 2015 to 2017 to examine the short-term dynamics of Abies koreana seedling and the change of vegetation distribution according to altitude. We analyzed the importance value and MIV (mean importance value) of major species by each stratum as well as the importance value and species diversity index of major species and the change of seedling population by altitude. The results showed that Abies koreana had the highest importance value on tree layer, Rhododendron schlippenbachii on shrub layer and Tripterygium regelii on herb layer. MIV was high in the order of Abies koreana, Rhododendron schlippenbachii and Acer pseudosieboldianum. Regarding the species composition and species diversity index (H') along the altitudinal gradient, Sasa borealis showed high MI and low H' in the elevation less than 1,500 m, and IV of Tripterygium regelii and H' of herb layer were high in the elevation of 1,700 - 1,800 m. Abies koreana seedling decreased by 22.4% from 1,250 n/ha in 2015 to 970 n/ha in 2017 (p <0.05) throughout the investigated area. The decline rate along seedling and sapling height were 22.9% in less than 10 cm, 3.4% in 10-30 cm, 8.9% in 30-50 cm, 39.3% in 50-100 cm, and 55.1% more than 100 cm. Few of A. koreana seedlings appeared due to the dominance of Sasa borealis in the elevation of 1,500 m or less and due to the dominance and high species diversity of Tripterygium regelii in the elevation of 1,700-1,800 m. On the other hand, many of A. koreana seedlings appeared in the elevation of 1,600-1,700 m due to no distribution of S. borealis and T. regelii species in that altitude range. Therefore, we concluded that those seedlings and saplings of A. koreana could be more stable in the altitude of 1,600-1,700 m.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.2
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• pp.133-142
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• 1990

For the purpose of investigation of demersal fisheries resources of the East China Sea, joint research between Hokkaido University and National Fisheries University of Pusan was carried out during the period from November 5 to November 12 in 1989. This joint research is due to continue for the next three years. In this report, the authors analyzed the catch of 24 draughts of trawl operating by the Oshorumaru of the training ship of Hokkaido University in the north area of the East China Sea, in order to hold the present condition of the demersal resources. The specimens collected were composed of 76 species of fishes, 6 of mollusca and 7 of crustacea. And the main species of the large catch were Raja kenojei, Zeus faber, Miichthys miiuy, Collichthys lucidus, Dentex tumifrons, Carangoides caeruleopinnatus, Trachurus japonicus, Parastromateus niger, Trichiurus leptulus, Scomberomorus niphonius, Pampus argenteus, Pampus echinogaster, Psenopsis anonala, Liparis tanakai, Thammaconus modestus, Tadarodes pacificus, Loligo edulis, and Portunus trituberculatus. Especially, Trichiurus leptulus, Pampus agrenteus and Thammaconus modestus had different modes of classes of body size individually, with changing of fishing ground. But, Tadarodes pacificus, Loligo edulis and Portunus trituberculatus were caught the maxed sizes of body individually in the same ground.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.129-150
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• 1985

The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.