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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.

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, ...

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.

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.