• 한국환경과학회지
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• 제20권12호
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• pp.1599-1605
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• 2011

To evaluate heat environment surrounding plants diurnal change of leaf temperature in the broad-leaved deciduous and evergreen trees was measured with microclimatic environmental factors including global solar radiation, and upward and downward long wave radiation. Maximum daily solar radiation was 961.2 and 976.3 w/$m^2$ in August 9 and 23, respectively. Upward long wave radiation was slightly higher than downward long wave radiation, showing 404.2 w/$m^2$ in August 9 and 394.5 w/$m^2$ in August 23. In addition, daily maximum vapor pressure deficit was 5.42 and 6.84 kPa in August 9 and 23, respectively, indicating high evaporative demand. Quercus glauca and Acer mono was differently responded to changing light regimes. On August 9, leaf temperature at the top-positioned leaves of Acer plants was higher than air temperature as well as those of Quercus plants in the morning. This indicates that stomata in Acer plants were closed by heat stress or water stress in the morning, while Quercus plant maintained active transpiration by opening stomata. These results indicated that improved light regimes such as gap opening in the closed forest may not always affect positively in the physiology of understory plants.

• ALGAE
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• 제27권1호
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• pp.9-19
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• 2012

Phlorotannins are common metabolites produced in kelps that can have deterrent functions against grazers. The factors dictating seasonal patterns of phlorotannin content in northeastern Pacific kelps are not well understood. This study assessed density and grazing of the gastropod Lacuna vincta on the annual canopy-forming kelp Nereocystis luetkeana and the perennial understory species Agarum clathratum, Saccharina latissima and S. groenlandica in Kachemak Bay, Alaska. In addition, we assessed seasonal patterns of environmental variables as possible drivers of phlorotannin concentrations. Phlorotannins occurred in all species, with overall lowest levels in N. luetkeana, and with different seasonal patterns among the four species. Lacuna vincta was most dense on N. luetkeana thalli in the summer and had highest grazing rates on this low-phlorotannin species. However, correlations between L. vincta density and phlorotannin content of each kelp species were not significant. Except for N. luetkeana, there were no correlations between phlorotannin levels and environmental variables. We suggest that kelp life history traits may be more important for phlorotannin patterns in these kelp species than grazers or environmental drivers.

• The Korean Journal of Ecology
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• 제6권3호
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• pp.187-197
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• 1983

This report is a series of the investigation of the secondary vegetation and succession at the forest fire area in Dangji-Dong of Kyungsang-pookdo province. The forest fires occurred on April 8, 1982. This investigation was carried out from June 18, 1982 to May 29, 1983 once in each season. Before to fires, the Pinus densiflora was dominant and the woody plants of understory were mainly composed of the Quercus serrata, Q. dentata, Lespedeza maritima and L. macimowiczii. Compared with the florstic composition between the unburned and burned areas after the fires, the floristic composition of unburned area comprises: 79 families, 194 genera, 223 species, 26 varieties and 6 formae (255 kinds of vascular plants). The index of similary shows 0.77 (S$\Phi$renson:1948) in this area. The analyses of the life-form compositions in the unburned and burned area show 32.9% and 29.3% in dormancy form (H), 42.4% and 37.7% in disseminule form($D_1$), 80.8% and 82.2% in radicoid form ($R_5$), and 57.7% and 61.8% in erect form(e) respectively. The biological type shows H-$D_1$-R5-e, which is common in both areas, and erect form is generally prevailing in these communities.

• Journal of Ecology and Environment
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• 제34권4호
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• pp.347-355
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• 2011

Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.

• 한국산림과학회지
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• 제94권5호통권162호
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• pp.338-341
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• 2005

This study was conducted to describe the differences in artificial nest boxes use of tits between deciduous and coniferous forests at 2nd campus of Chung-Ang University ($37^{\circ}00^{\prime}04^{{\prime}{\prime}}N$, $127^{\circ}13^{\prime}96^{{\prime}{\prime}}E$), Ansung, Korea from January to August 2005. Tree species richness, tree species diversity index (H') and total basal areas were higher in deciduous forest than in coniferous forest. High, middle, low and understory canopy layers were more developed in deciduous forest, except the coverage of bush-ground layer. Varied tit Parus varius, marsh tit P. palustris and great tit P. major used the artificial nest boxes in this study. Number of breeding pairs of tits used artificial nest boxes, clutch size, and weight and size of eggs were higher in deciduous forest than in coniferous forest. The differences in habitat structure between study sites are very likely to have influenced how breeding birds used the available habitat. Artificial nest boxes could be used as management and conservation tool for birds, particularly in areas, where the availability of natural cavities and coverage of higher layer are limited.

• 생명과학회지
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• 제15권3호
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• pp.447-452
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• 2005

본 조사 지역은 도심의 자연공간이 비록 인위적 조성이긴 하나 질적 및 양적으로 식생이 양호하게 잘 관리할 수 있음을 단적으로 보여 주었다. 식물상은 광범위한 조사 지역이 아님에도 불구하고 세 가지 특징이 있다. 첫째는 교과서적인 이차림에 의한 군락이 매우 양호하다는 점이다. 그러나 자연지역에서는 군락 형성이 미미했다. 둘째는 다양도는 자연집단에서는 높게 나타나고 조림지에서는 낮았다. 셋째, 자연 식생과 조림지의 종조성, 종다양도, 산림의 생산력에서 확연히 차이가 드러났다.

• ALGAE
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• 제32권1호
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• pp.41-46
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• 2017

In rocky intertidal habitats, abiotic stress due to desiccation and thermal extremes increases with elevation because of tides. A study in Atlantic Canada showed that, at low elevations where conditions are benign due to the brief low tides, fucoid algal canopies (Ascophyllum nodosum and Fucus spp.) do not affect the structure of benthic communities. However, at middle and high elevations, where low tides last longer, fucoid canopies limit abiotic extremes and increase the richness (number of invertebrate and algal species, except fucoids) of benthic communities. Using the data from that study, this paper compares the intensity of facilitation and its importance (relative to all other sources of variation in richness) between middle and high elevations, which represent intermediate and high stress, respectively. Facilitation intensity was calculated as the percent increase in benthic richness between quadrats with low and high canopy cover, while the importance of facilitation was calculated as the percentage of variation in richness explained by canopy cover. Data for 689 quadrats spanning 350 km of coastline were used. Both the intensity and importance of facilitation were greater at middle elevations than at high elevations. As canopies do not affect benthic communities at low elevations, this study suggests that the facilitation-stress relationship at the community level is unimodal for this marine system. Such a pattern was found for some terrestrial systems dominated by canopy-forming plants. Thus, it might be ubiquitous in nature and, as further studies refine it, it might help to predict community-level facilitation depending on environmental stress.

• 대한공간정보학회지
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• 제24권4호
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• pp.3-11
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• 2016

Sixty four percent of Korean territory consists of forest which is fragile for forest fire. However, it is difficult to detect the disaster-induced damages due to topographic complexity in mountainous areas and harsh weather conditions. For this reason, satellite imaging systems have been widely utilized to detect the damage caused by forest fire. In particular, ground vegetation condition can be estimated from multi-spectral satellite images and change detection technique has been used to detect forest fire damages. However, since Korea has clear four seasons, simple change detection technique has limitation. In this regard, this study applied the NDVI(normalized difference vegetation index) annual cycle modeling technique on time-series of Landsat images from 1991 to 2007 to analyze influence of forest fire of Yangyang-gun, Gangwon-do in 2005 on vegetation condition. The encouraging result was obtained when comparing the areas where forest fire occurs with non-damaged areas. The mean value of NDVI was decreased by 0.07 before and after the forest fire. On the other hand, annual variability of NDVI had been increasing and peak value of NDVI was stationary after the forest fire. It is interpreted that understory vegetation was seriously damaged from the forest fire occurred in 2005.

• Journal of Ecology and Environment
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• 제41권3호
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• pp.54-65
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• 2017

Background: "Igune," a traditional agricultural landscape in the Tohoku region of Japan, is characterized by small-scale artificial woodlots surrounding a farmer's house that are interspersed with paddy fields. During the rapid economic growth of Japan over recent decades, some igune woodlots have been abandoned or logged. Biodiversity conservation is an important issue worldwide, and traditional agricultural landscapes are of particular interest. To elucidate the role of igune landscapes in conserving biodiversity, we examined the effects of environmental factors on avian communities. Results: The study was conducted in the suburban areas of Oshu and Hanamaki cities, Iwate Prefecture, Japan, at eight sites that varied in the density and area of igune woodlots within the landscape. Bird surveys were conducted from the middle to late breeding season, and several environmental factors of the igune landscape were also measured. The results of canonical correspondence analysis indicated that the characteristics of avian communities were mainly determined by the total forested area in the landscape. Increased total forested area and shrubs layer of igune woodlots did not cause a reduction in number of bird species of any habitat and foraging types, while increased both in species number and abundance of insectivores and forest species. The number of raptor species increased in igune sites without shrubs. Conclusions: Our results suggest that maintaining igune landscapes may enhance avian diversity within this landscape, although the effects of shrubs within igune varied; developed bush communities increased the evenness of the avian community, whereas some raptor species preferred an open forest understory.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.55-64
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• 1996

This is a report on the recovery of vegetation and secondary succession in the burned area studied from April, 1990 to April. 1991. The forest fire occurred in a part of Mt. $K\v{u}mo-san$ on April, 1986 and the pine forest and its understory vegetation were burned out completely. The floristic compositions of burned (B) and unburned (U) areas were composed of sixty eight and thirty one species (vascular plants), respectively. These species were divided into invaders (47 species), increasers (15 species), deceasers (3 species), neutrals (3 species), and retreaters (10 species) on the basis of summed dominance ratio ($SDR_3$). Biological spectra showed the $H-D_1-R_5-e$ type in both the burned and unburned areas. The species of Lespedeza ($SDR_3$=94.7), Miscanthus (91.95), Festuca (68.33), and Spodiopogon (52.06) were dominant in the burned areas, while the species of Pinus (76.67), Robinia (56.25), Quercus (52.08), and Carex (40.25)were dominant in the unburned area. Dominance index (C) in burned and unburned areas was 0.15 and 0.25, respectively. the index of similarity (CCs) was 0.42. The degree of succession (DS) and species diversity (H) in burned and unburned areas were 675.8, 884.2 and 4.07, 2.05, respectively. The degree of succession in the burned area graduall increased and the burned area was recovered to be simmilar to the unburned area. Evenness index in burned and unburned areas was 0.965 and 0.595, respectively.