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The river is a dynamic space where erosion, transportation, and sedimentation are constantly occurring due to running water. This study aims to reveal the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to that. This study was carried out by clarifying the spatially appearing successional trends in the vegetation established in the stream bars and the riparian zones, which are located on different topographic conditions based on the vegetation profile, ordination result, and species diversity. The spatial distribution of vegetation on the stream bars tended to appear in the order of annual plant-, perennial plant-, and tree-dominated stands from the upstream toward a downstream direction (a gravel bar and a sand bar in a mountain gravel-bed river and an estuary, respectively) or the reversed one (a sand bar in a lowland river). The spatial distribution of vegetation on the riparian zones tended to appear in the order of annual plant-, perennial plant-, and tree-dominated stands from the waterfront toward the bank direction. Changes in species composition also differed depending on the spatial location, showing a similar trend to the spatial distribution of vegetation. Species diversity became higher in proportion to the longevity of the dominant species of each vegetation type. In conclusion, the longitudinal distribution pattern of vegetation on the stream bars resembles the lateral distribution of riparian vegetation, and the successional trends follow the spatial distribution pattern. These results suggest that the dynamics of bed loading, an allogenic process, may be an important determinant of the spatial distribution and succession of plant communities in dynamic riverine environments.

The relationship between landscape structure and biodiversity was investigated in the Gyungan stream basin, central Korea, in order to prepare a biodiversity conservation plan. The study area was divided into upstream, midstream, downstream and Gonjiam stream sub-watersheds based on the land use pattern of each sub-watershed. The quality of the terrestrial landscape was assessed by connectivity and percentages of deciduous broad-leaved forest and urbanized area. The quality of the terrestrial landscape was the highest in the downstream sub-watershed followed by Gonjiam stream, midstream and upstream sub-watersheds. The quality of the riparian landscape assessed by percentages of the number and the area that the wetland vegetation elements occupy in the whole area showed a similar trend to that of terrestrial landscape. The diversity of all taxa including fish, reptiles and amphibians, birds, mammals and wetland vegetation except benthic macroinvertebrates was the highest downstream. The diversity of benthic macroinvertebrates was the highest in the Gonjiam stream sub-watershed. Thus, biodiversity was shown to be the highest in the downstream sub-watershed, followed, in order, by Gonjiam stream, midstream and upstream sub-watersheds in proportion to landscape quality. On the other hand, the quality of the aquatic environment based on the ecological score of benthic macroinvertebrate (ESB) index was the highest downstream, followed, in order, by upstream, Gonjiam stream and midstream areas. This trend is different from that of biodiversity. In order to improve landscape quality degraded by excessive land use and to increase biodiversity, we recommended a restoration plan that addresses both ecosystem and landscape.

To investigate the variation in seasonal soil respiration (SR) as a function of soil temperature (Ts) and soil water content (SWC) in Mongolian oak (Quercus mongolica) forests in urban (Mt. Nam) and well-reserved (Mt. Jeombong) areas in South Korea, we conducted continuous field measurements of SR and other environmental parameters (Ts and SWC) using an automated chamber system. Overall, the SR rates in both stands were strongly correlated with the Ts variable during all seasons. However, abrupt fluctuations in SR were significantly related to episodic increases in SWC on a short time scale during the growing season. The integrated optimal regression models for SR using Ts at a depth of 5 cm and SWC at a depth of 15 cm yielded the following: the SR rate in Mt. Nam = SR(Ts) + ΔSR(Ts) = 104.87 exp(0.1108Ts) − 10.09(SWC)2 + 604.2(SWC) − 8627.7 for Ts ≥ 0 °C, and the SR rate in Mt. Jeombong = SR(Ts) + ΔSR(Ts) = 95.608 exp(0.1304Ts) − 33.086(SWC)2 + 1949.2(SWC) − 28499 for Ts ≥ 0 °C. In both cases, SR = 0 for Ts &lt, 0 °C. As per these equations, the estimated annual total SRs were 1339.4 g C m−2 for Mt. Nam and 1003.0 g C m−2 for Mt. Jeombong. These values were quite similar to the measured values in field. Our results demonstrate that the improved empirical equation is an effective tool for estimating and predicting SR variability and provide evidence that the SR of Q. mongolica forests in the cool temperate zone of Korean Peninsula depends on Ts and SWC variables.

To select a tolerant plant species for restoring a forest ecosystem that had been severely damaged by air pollutants discharged from the industrial complex, 26 sample plants were transplanted in the mountainous area around the Yeocheon Industrial Complex in southern Korea. This transplanting experiment has been in progress for 20 years from 1994 to 2013. Ten plant species died and 16 plant species survived during the transplanting experiment period. Among the surviving 16 plant species, we chose five species, Alnus firma, Eurya japonica, Styrax japonica, Ligustrum japonicum, and Sorbus alnifolia as the very tolerant species, and four species, Pinus densiflora, Elaeagnus umbellata, Quercus dentata, and Fraxinus rhynchophylla as the tolerant species. We prepared a vegetation map by interpreting aerial photographs for diagnostic assessment of the forest vegetation damaged by air pollution. We estimated grassland, shrubland, and forest on the vegetation map as vegetation types that were severely, moderately, ...

This study aimed to analyze spatio-temporal trends of phenological characteristics in South Korea by using MODIS EVI. For the phenology analysis, we had applied double logistic function to MODIS time-series data. Our results showed that starting date of phenology seems to have a tendency along with latitudinal trends. Starting date of phenology of Jeju Island and Mt. Sobeak went back for 0.38, 0.174 days per year, respectively whereas, Mt. Jiri and Mt. Seolak went forward for 0.32 days, 0.239 days and 0.119 days, respectively. Our results exhibited the fluctuation of plant phonological season rather than the change of phonological timing and season. Starting date of plant phenology by spatial distribution revealed tendency that starting date of mountain area was late, and basin and south foot of mountain was fast. In urban ares such as Seoul metropolitan, Masan, Changwon, Milyang, Daegu and Jeju, the phonological starting date went forward quickly. Pheonoligcal attributes such as starting date and leaf fall in urban areas likely being affected from heat island effect and related warming. Our study expressed that local and regional monitoring on phonological events and changes in Korea would be possible through MODIS data.

In Korea, where the plain land is greatly deficient as a mountainous nation, most of riparian zones were transformed into agricultural fields and urban areas. Excessive use of the land, which is close to river, makes the rivers enduring severe pollution stresses. Disappearance of riparian buffer, which plays a function of filter in the riverside, appears as a main factor aggravating water pollution of rivers. In this respect, it is imperative to restore the lost riparian vegetation. This study found out restoration models of riparian vegetation from the Bongseonsa stream, which has remnant riparian vegetation patches as a conservation reserve. Feasible reference information applicable for restoration of riparian vegetation was shown in the species level in the order of herb, shrub, and tree and sub-tree zones as far away from the waterway. Those information could contribute to restoring integrate and healthy rivers and streams beyond simple landscaping differently from the other restoration projects when they will be applied to the restoration project to be carried out in the future. In addition, the spatial range of river and stream, background that riparian zone disappeared in Korea, and application plan of the obtained reference information were discussed.

A Gram-stain-negative, non-motile, deep yellow, rod-shaped bacterium, designated strain LCS9T, was isolated from a soil sample at the tropical zone within the Ecorium of the National Institute of Ecology in Seocheon, central-western Korea. 16S rRNA gene sequence analysis showed that strain LCS9T clustered with members of the genus Flavisolibacter of the family Chitinophagaceae , phylum Bacteroidetes . Sequence similarities between strain LCS9T and the type strains of the genus Flavisolibacter ranged from 94.6 to 94.9 %. Strain LCS9T grew at 10–37 °C (optimum, 25 °C) and at pH 6.0–10.0 (optimum, pH 7); was positive for catalase and oxidase; and negative for nitrate reduction and production of indole. Cells showed pigment absorbance peaks at 451 and 479 nm, and had 0.03 % survival following exposure to 3 kGy gamma radiation. Strain LCS9T had the following chemotaxonomic characteristics: the major quinone was menaquinone-7 (MK-7); the major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH; polar lipids included phosphoatidylethanolamine, an unidentified aminophospholipid, unidentified aminolipidsand unidentified lipids. The DNA G+C content was 39.4 mol%. Based on polyphasic analysis, the type strain LCS9T (=KCTC 42070T=JCM 19972T) represents a novel species for which the name Flavisolibacter tropicus sp. nov. is proposed. Radiation resistance in the genus Flavisolibacter has not been reported to date, and so this is the first report of low-level radiation resistance of a member of the genus.

Species composition, frequency distribution of diameter classes, species diversity, and stem vitality of woody plants were analyzed in a Mongolian oak (Quercus mongolica Fisch. ex Ledeb.) forests in permanent quadrates of Mt. Nam and Mt. Jeombong, which were installed for Long Term Ecological Research (LTER). The principal objective of this study was to clarify the ecological characteristics of both sites by comparing the Mongolian oak communities established in Mt. Nam surrounded by urban area and in Mt. Jeombong as a natural area, to accumulate the basic data for long-term monitoring, and furthermore to predict possible changes in vegetation due to climate change. The species composition of the Mongolian oak community on Mt. Nam differed from that of Mt. Jeombong. Such differences were usually due to Sorbus alnifolia, Styrax japonicus, Oplismenus undulatifolius, Ageratina altissima and so on, which appeared in higher coverage in Mt. Nam. Species diversity of the Mongolian oak community in Mt. Nam was lower than that in Mt. Jeombong. This result was attributed to the fact that the Mongolian oak community in Mt. Nam is under continuous management and was dominated excessively by S. alnifolia, and S. japonicus, which were originated from artificial in terference and chronic air pollution. As the results of analyses on the frequency distribution of diameter classes of major tree species and the transitional probability model based on Markov chain theory, the Mongolian oak community in Mt. Nam showed a possibility of being replaced by a S. alnifolia. Considering that this replacement species is not only a sub-tree but is also shade-intolerant, such a successional trend could be interpreted as a sort of retrogressive succession. The Mongolian oak community established in Mt. Jeombong differed from the community in Mt. Nam in terms of its probability of being continuously maintained.

The Namsan Ecological Tower Site based on a flux tower was equipped with eddy covariance and automatic opening/closing chamber systems to collect long-term continuous measurements of flux, such as the net ecosystem exchange (NEE) and soil efflux in a cool-temperate Quercus mongolica forest. The mean concentrations of atmospheric () during the summer were smaller than those measured () during the winter. The mean flux during the summer period was negative (), while that during the winter period was positive (). was deposited from the atmosphere to the surface in the summer. The daily mean value of soil efflux increased from spring to summer. The seasonal pattern in the rate of soil efflux tightly followed the seasonal pattern in soil temperatures. The values for soil efflux varied in a range from 2.12 to 3.26, and increased with increasing soil depth. The maximum value of total carbon uptake (i.e., NEE) during the growing season was . At the same time, the rate of soil efflux was . The amplitude of flux variations in NEE was approximately 14% larger than those in soil efflux. These results suggest that in cool-temperate regions of the Korean peninsula, the forest ecosystem of Q. mongolica may have a larger atmospheric uptake, due primarily to its high photosynthetic capacity and low ecosystem respiration.

We evaluated the restoration effect by introducing willows as a means of controlling invasions of giant ragweed (Ambrosia trifida L.) on a riparian site. Our preliminary survey demonstrated that a problematic exotic species, giant ragweed and the representative riparian species, Salix koreensis are in competitive exclusive relationship. We planted willows at 1 m intervals on the bank of the Dongmun stream at Munsan, Paju, in Central Western Korea as an experimental restoration practice. We installed two 50 m ⅹ 5 m sized restored and non-restored for this experimental study. The non-restored plots were located on river banks, which were covered with concrete blocks and left in itself without any treatment. The height of willow was measured after each of three consecutive growing seasons and compared with the height of the giant ragweed. Although the height of Salix gracilistyla did not achieve the height of the giant ragweed, the height of S. koreensis surpassed that of giant ragweed in the third year after introduction. The results were also reflected in the relative light intensity on the herb layer of willow stand, and thereby the relative light intensities of stands, which were dominated by S. koreensis or restored by introducing S. koreensis, 1.99 ± 0.33 (%, mean ± SD) and 1.92 ± 0.50 (%, mean ± SD), respectively were lower than those in the stands treated by S. gracilistyla, 3.01 ± 0.43 (%, mean ± SD). The giant ragweed stands receive full sunlight as there are no any vegetation layers higher than the herb layer formed by the giant ragweed. As the result of Detrended Correspondence analysis ordination based on naturally established vegetation, the stands dominated by willows and giant ragweed showed different species composition between both stands. The species composition of the restoratively treated sites resembled the reference sites more than the non-treated sites. The species diversity (H’) of the sites restored by introducing S. koreensis and S. gracilistyla was higher than the non-restored site dominated by A. trifida . On the basis of our results, the restoration of riparian vegetation equipped with integrated features could contribute not only to the control of exotic plants including giant ragweed but also to ensure the diversity and stability of riverine ecosystems.

This paper proposes an invertible semi-fragile video watermarking algorithm using a hash function to authenticate the video contents. It can protect the video content from malicious manipulations and detect the modified part of the video. Also the proposed algorithm has the invertible property, which allows us to get the original video data back if they are authentic.