• Journal of Ecology and Environment
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• v.43 no.4
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• pp.438-453
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• 2019

Background: To investigate the trends of succession occurring at the Pinus thunbergii forests on the lowlands of Jeju Island, we quantified the species compositions and the importance values by vegetation layers of Braun-Blanquet method on the Pinus thunbergii forests. We used multivariate analysis technique to know the correlations between the vegetation group types and the location environmental factors; we used the location environment factors such as altitudes above sea level, tidal winds (distance from the coast), annual average temperatures, and forest gaps to know the vegetation distribution patterns. Results: According to the results on the lowland of Jeju Island, the understory vegetation of the lowland Pinus thunbergii forests was dominated by tall evergreen broad-leaved trees such as Machilus thunbergii, Neolitsea sericea, and Cinnamomum japonicum showing a vegetation group structure of the mid-succession, and the distribution patterns of vegetation were determined by the altitudes above sea level, the tidal winds on the distance from the coast, the annual average temperatures, and the forest gaps. We could discriminate the secondary succession characteristics of the Pinus thunbergii forests on the lowland and highland of Jeju Island of South Korea. Conclusions: In the lowland of Jeju Island, the secondary succession will progress to the form of Pinus thunbergii (early successional species)→Machilus thunbergii, Litsea japonica (mid-successional species)→Machilus thunbergii (late-successional species) sequence in the temperate areas with strong tidal winds. In the highland of Jeju Island, the succession will progress to the form of Pinus thunbergii (early successional species)→Neolitsea sericea, Eurya japonica (mid-successional species)→Castanopsis sieboldii (late-successional species) sequence in the areas where tidal winds are weak and temperatures are relatively low. However, local differences between lowland and highland of Jeju Island will be caused by the micro-environmental factors resulting from the topographic differences and the supply of tree seeds. From the characteristics of succession study, we could properly predict and manage the Pinus thunbergii forest ecosystem on lowland and highland of Jeju Island.

• Journal of Plant Biology
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• v.33 no.2
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• pp.147-150
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• 1990

Different species with similar niches can coexist in the same community if disturbances prevent compeptitive exclusion of competitively inferior species. Disturbances which open up gaps are common in all kind of community. Even in virgin forests without any artificial disturbance, there exist a significant proportion of trees of early successional shade-in-tolerant species in addition to the dominant late successional shade-tolerant species. In forest ecosystems, most canopy tree species including shade-tolerant ones require one or more gaps in their life-time to reach the canopy. Because of these frequent disturbances, forests can be considered of dynamic mosaics of patches of different ages and with different species composition which are in certain stages of recovery from disturbances. Disturbances temporarily increase the availability of resources such as light, water and soil nutrient for other in dividuals through the death of one or more canopy trees.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.126-142
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• 2020

Background: Most of the Pinus densiflora forests, occupying the largest area, have been restored in South Korea since the 1970s. As young pioneer forests, the succession process is under way. Since the forests are distributed nationwide and are vulnerable to disturbances, the process may differ depending on the geography and/or site conditions. Therefore, we reviewed the direction, the seral communities, and the late-successional species of progressive and disturbance-driven succession nationwide in the cool-temperate zone through meta-analysis and empirical observations. Main text: As a result of a meta-analysis of the direct succession and vertical structure, we found that the P. densiflora forest is in a directionally progressive succession, changing to the broadleaved forest after forming a mixed forest with its overwhelming successor, Quercus species (particularly Q. mongolica and Q. serrata). In dry stands in a relative sense, the Quercus species was favored occupying over 80% of the abundance of the succeeding species. Therefore, in dry stands, it is presumed that Quercus-dominated stage would last for a long time due to the current dominance and long life span, and eventually, it settles as Quercus-broadleaved forest with a site change. Contrary to this, it is presumed that in mesic stands where Quercus species do not occur or have low abundance, the late-successional broadleaved species settle early to form a co-dominant forest with multiple species. Due to geographical limits, the species composition of the two late-successional forests is different. Disturbances such as insect pests and fire retrogressed vulnerable P. densiflora forest for a while. However, it was mostly restored to the Quercus forest and is expected to be incorporated in the pathway of the dry stand. Conclusions: We revealed the succession process of P. densiflora forests according to geography and moisture and found that stand moisture had a decisive effect on the species and abundance of the successor. Although the P. densiflora forest is undergoing structural changes, the forest is still young; so within a few decades, physiognomy is not likely to change. Therefore, the decrease in the forest area may be due to other causes such as disturbances and forest conversion rather than due to succession.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.3
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• pp.83-95
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• 2013

To understand natural regeneration and stand development after fire in mixed broadleaved-coniferous forests of Sikhote-Alin Mountains, ten sample plots of $50m{\times}50m$ size were established in 1975 and 1983 at the stands burned by wildfires in 1973 and 1982, respectively. And, the number of naturally regenerated seedlings were monitored in two $50m{\times}4m$ subplots in each plot. The most fire-sensitive conifer species is Abies nephrolepis, while Betula costata is the most fire-sensitive broadleaved tree species. The most fire-resistant species were Q. mongolica, T. taquetii and A. mono. The results of 20 and 30 years after the fire showed that pioneer tree species, e.g. Populus, Salix, and Betula, were regenerated immediately at the early stage of stand development and grew where there is a mono canopy layer with high density. On the other hand, the densities of successors, e.g. Pinus koraiensis, Picea jezoensis, Abies nephrolepis, Acer mono and Tilia taquetii, which were present in the study plots before the fire, increased gradually. Naturally regenerated tree species after forest fire by the growth rate were divided into three groups according to their annual height growth. The seral tree species (Betula costata, Betula platyphylla, Padus maackii, Populus tremula and Sarix caprea) belong to the first group and have the highest growth rate (from 40 to 96 cm per year). The late successional broad-leaved trees (Tilia taquetii, Acer mono and Quercus mongolica) belong to the second group and have intermediate annual height growth (from 3.7 to 13.5 cm per year). The late successional coniferous species (Picea jezoensis, Pinus koraiensis and Abies nephrolepis) form the third group and have the least annual height growth (from 1.4 to 3.5 cm per year).

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.52-63
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• 2019

This study analyzed the characteristics of vegetation structure of the camphor tree (Cinnamomum japonicum) community in the area of mount Tachibana, Kasuya county, Fukuoka Prefecture designated as a special natural monument in Japan. The survey showed overwhelming dominance of canopy tree in the canopy layer (about 30 m in tree heights and 92.79 cm in average breast height diameter) but no appearance in the understory layer or the shrub layer. In the understory layer and the shrub layer, Castanopsis sieboldii, Machilus thunbergii, Neolitsea sericea, and Cinnamomum yabunikkei, which were the competing species to the canopy layer and the late-successional species in the warm temperate climate zone, were mainly distributed. Moreover, the species diversity was generally low, indicating the vegetation characteristics that was not typical of evergreen broad-leaved forests. This is presumably because camphor trees were actively planted, protected, and cultivated to produce camphor which was valuable in the past. Although this site has not been artificially managed for the past 90 years as the raw materials of camphor have not been collected, vegetation transition did not proceed, which is unique. It is probably due to the fact that camphor was overwhelmingly dominant in the canopy layer so that the inflows of species were restricted, and young tree germination did not occur due to the allelopathy effects of camphor trees.

• Journal of Ecology and Environment
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• v.47 no.2
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• pp.49-62
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• 2023

Background: Over the past three decades, gradual eustatic sea-level rise has been considered a primary exogenous factor in the increased frequency of flooding and biological changes in several salt marshes. Under this paradigm, the potential importance of short-term events, such as ocean storminess, in coastal hydrology and ecology is underrepresented in the literature. In this study, a simulation was developed to evaluate the influence of wind waves driven by atmospheric oscillations on sedimentary and vegetation dynamics at the Skallingen salt marsh in southwestern Denmark. The model was built based on long-term data of mean sea level, sediment accretion, and plant species composition collected at the Skallingen salt marsh from 1933-2006. In the model, the submergence frequency (number yr^-1) was estimated as a combined function of wind-driven high water level (HWL) events (> 80 cm Danish Ordnance Datum) affected by the North Atlantic Oscillation (NAO) and changes in surface elevation (cm yr^-1). Vegetation dynamics were represented as transitions between successional stages controlled by flooding effects. Two types of simulations were performed: (1) baseline modeling, which assumed no effect of wind-driven sea-level change, and (2) experimental modeling, which considered both normal tidal activity and wind-driven sea-level change. Results: Experimental modeling successfully represented the patterns of vegetation change observed in the field. It realistically simulated a retarded or retrogressive successional state dominated by early- to mid-successional species, despite a continuous increase in surface elevation at Skallingen. This situation is believed to be caused by an increase in extreme HWL events that cannot occur without meteorological ocean storms. In contrast, baseline modeling showed progressive succession towards the predominance of late-successional species, which was not the then-current state in the marsh. Conclusions: These findings support the hypothesis that variations in the NAO index toward its positive phase have increased storminess and wind tides on the North Sea surface (especially since the 1980s). This led to an increased frequency and duration of submergence and delayed ecological succession. Researchers should therefore employ a multitemporal perspective, recognizing the importance of short-term sea-level changes nested within long-term gradual trends.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.4
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• pp.29-41
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• 2015

Abandoned paddy field provides an excellent opportunity to improve the species diversity and habitat quality. Ecological characteristic on the changing of plant communities at different seral stages is a major basis data for ecological restoration. In this study, we investigated changes of the species composition and community indices on the plant community associated with abandonment of cultivated rice paddies. The ecological stability of the habitat was evaluated by using eco-floristic characters(Di; Disturbance index, AUI; Actual urbanization index). Survey sites were grouped into six stages(stageI (${\leq}3years$), stageII(3-5years), stageIII(5-7years), stageIV(7-10years), stageV(10-15years), stageVI(${\geq}20years$). Vegetation investigation was done from May 2009 to October 2012 and carried out phytosociological approach. The total flora were summarized as 176 taxa including 58 families, 127 genera, 157 species, 3 subspecies, 15 varieties and 1 forms. At each of successional stages, 64 taxa in stage I, 34 taxa in stage II, 84 taxa in stage III, 83 taxa in stage IV, 92 taxa in stage V, 23 taxa in stage VI were identified. Of the occurrence plants, the species with the highest r-NCD value were Alopecurus aequalis, Juncus effuusus var. decipiens, Persicaria thunbergii, Artemisia princeps, Salix koreensis and Alnus japonica at each stages. Herbaceous annual plants were dominated in the early stage, but its r-NCD value declined in the middle stage and the late stage. On the other hand, herbaceous perennial plants and Persicaria thunbergii, annual hydrophytes, increases in the middle stage. Woody plant and herbaceous plant which appeared in the forest edge increases in the late stage. Community indices correlate with successional stages. Richness and diversity index increase along the successional gradient. But dominance index decrease along the successional gradient. Evenness index was correlated with lower. In the ecological stability analysis of the habitat that evaluated by eco-floristic characters, stage I was the most unstable habitat. And the stability of the habitat has improved according to the successional stage.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.337-344
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• 1998

To select tolerant species among the Korean major woody plants for restoring disturbed ecosystems by air and soil pollution, we transplanted the seedlings of 56 species in control and polluted sites within Yeocheon industrial complex area, and compared their aboveground growth characteristics such as total branch length, total leaf weight, and maximum photozynthetic rate. Tolerant species growting better in polluted site than in control site was Quercus variabilis, Pinus thunbergii, Q. aliena, P. densiflora, Styrax japonica, Alnus firma, Celtis sinensis, Elaeagnus umbellata, Q. serrata, japonica, Sorbus alnifolia, and Q. acutissimia in local tree occuring within polluted area group (80%), Ailanthus altissima in street tree group (20%), Populus tomentiglandulosa and A. hirsuta var. sibirica in fast growing tree group (50%), Acer ginala and Abies holophylla in late successional tree group (20%), Betulla platyphylla var. japonica, Acer truncatum, A. palmatum, Syringa dilatata, and Rosa multifora in garden tree group (38%), and Q. rubura, and Robinia pseudoacacia in foreign restoring tree group (20%), respectively. The remaining plant species, 37 species (57% of total species), were classified into sensitive species to pollution. Those tolerant species can be utilized for restoration of the degraded ecosystem in this polluted area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.1
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• pp.82-87
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• 2015

For the ecological evaluation of marine algal vegetation, flora and their communities were surveyed seasonally at Goseong, on the southern coast of Korea. A total of 102 algal species, comprising 17 green, 18 brown and 67 red algae, was identified. Representative dominant species were assessed as Ulva australis, Sargassum thunbergii, and Gelidium amansii. Of these, Ulva australis was remarkably dominant in all seasons. High biomass of the dominant species were recorded. The total seasonal biomass was highest in winter and lowest in summer. The mean biomass value was $1315.6g/m^2$ across the four seasons. Each species was classified into six functional groups, and two ecological state groups (ESG) were evaluated based on these groups. While ESG I, the late successional species group, formed only 18.6% of the algal community; ESG II, composed of opportunistic species, comprised 81.4%. This suggests that environmental stress has been continuously imposed on the marine algal vegetation of the present study area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.28-44
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• 1998

This study was conducted to suggest the ecological restoration strategies for the disturbed landscapes by theoretical study. Especially, it is aimed to suggest three objectives for restoration by using native plants ; (1) prevention or reduction of wind and water erosion, (2) provision of food and cover for variety of animal species, (3) improvement of the visual or aesthetic quality of disturbed sites. The main results were summarized as follows. 1. Cooperation between restoration ecologists and restoration practitioners is needed to delineate a scientific approach to restoration ; (1) Being aware of published literature that describes similar work and/or establish general principles. (2) Preparedness to carry out proper experiments to test ideas. (3) Preparedness to monitor fundamental parameters in a restoration scheme. (4) Providing information about the behavior of species. (5) Publish results. 2. There are three models of succession in theories of plant succession. The tolerance and facilitation models were recommended to ecological restoration. The inhibition model applies in most secondary succession, but the actual species which are introduced first may inhibit the germination and growth of slower-growing species, or they may prevent the growth of other species whose propagules arrive later. 3. The objectives of erosion control, wildlife habitat provision, and visual quality improvement are not mutually exclusive. However, many revegetation practices in the past have emphasized one of these aspects at the expense of the others. 4. A native plant community can be the model of ecological restoration. By stylization/abstraction of native plant community, trying to learn the most essential characteristics of community types - environmental factors ; dominant, prevalent, and "visual essence" species composition - in order to use such information in restoration. 5. After developing mass/spaces plan, match plant communities to the mass/space plan. In utilizing community grouping, there needs aesthetic ability to understand design elements. 6. Several hydrophytes such as Pennisetum saccharifluous, Themeda triandra, Cirsium pendulum show relatively good germination rates. In case of mesophytes and xerophytes, Arundinella hina, Artemisia princeps, Oenothera odorata and legumes seem to have quick-germinating abilities at barren sites. Pinus thunbergii, Rhus chinensis, Evodia daniellii, Alnus firma and Albizzia julibrissin can be considered as "late succession" woody plants because they show low germinating rates and slow growing habitat. 7. The seeds used for restoration should be collected within a certain radius of where it will be planted. Consideration in genetic issues in the collection and use of germplasm can increase the odds for successful restoration efforts. 8. The useful model in the "drift" pattern occurs so abundantly in naturally evolving landscapes. As one species diminishes in density, a second or third species are increased. Thus, dynamic interactions between species are created. Careful using of "drift phenomenon" in planting was recommended. 9. Virtually no stand of vegetation today is immune from the introduction and/or spreading of exotic species. Therefore, the perpetuation of a restored sites requires conscious monitoring and management. Thus, management would be the most important process in ecological restoration. 10. In order to keep the sites "natural", alternative management strategies would be applied in management ; Atenative management strategies are decelerating successional process, accelerating successional processes or modifying species composition. As management tools, mechanical, chemical, biological or environmental factor manipulation, e.g., fire could be used.