This study was performed to characterize the ability of an active Bifidobacterium strain to produce conjugated linoleic acid (CLA) and to test its possible utilization as a probiotic compatible to the ruminal condition. Bifidobacterium breve LMC520 can actively convert linoleic acid (LA) to cis-9,trans-11-CLA, which is a major isomer derived from microbial conversion. LMC520 showed reasonable tolerance under acidic conditions (pH 2.5 with 1% pepsin) and in the presence of oxgall (0-3%). The growth and CLA production of LMC520 were tested under ruminal conditions and compared with those of Butyrivibrio fibrisolvens A38, which is a major CLA producer in the rumen as an intermediate in the biohydrogenation (BH) process. LMC520 converted 15% of LA to CLA under ruminal conditions, which was 2 times higher activity than that of A38, and there was no decline in CLA level during prolonged incubation of 48 h. The BH activity of LMC520 was comparable to that of A38. When LMC520 was cocultured with A38, even with slight decrease of CLA due to high BH activity by A38, but the level of CLA was maintained by the high CLA-producing activity of LMC520. This comparative study shows the potential of this strain to be applied as a functional probiotic not only for humans but also for ruminants as well as to increase CLA production.

Natural regeneration in forest management, which relies on artificial planting, is considered a desirable alternative to reforestation. However, there are large uncertainties regarding the natural regeneration processes, such as seed production, seed dispersal, and seedling establishment. Among these processes, seed dispersal by wind must be modeled accurately to minimize the risks of natural regeneration. This study aimed to (1) review the main mechanisms of seed dispersal models, their characteristics, and their applications and (2) suggest prospects for seed dispersal models to increase the predictability of natural regeneration. With improving computing and observation systems, the modeling technique for seed dispersal by wind has continued to progress steadily from a simple empirical model to the Eulerian-Lagrangian model. Mechanistic modeling approaches with a dispersal kernel have been widely used and have attempted to be directly incorporated into spatial models. Despite the rapid development of various wind-dispersal models, only a few studies have considered their application in natural regeneration. We identified the potential attributes of seed dispersal modeling that cause high uncertainties and poor simulation results in natural regeneration scenarios: topography, pre-processing of wind data, and various inherent complexities in seed dispersal processes. We suggest that seed dispersal models can be further improved by incorporating (1) seed abscission mechanisms by wind, (2) spatiotemporally complex wind environments, (3) collisions with the canopy or ground during seed flight, and (4) secondary dispersal, long-distance dispersal, and seed predation. Interdisciplinary research linking climatology, biophysics, and forestry would help improve the prediction of seed dispersal and its impact on natural regeneration.

Biodiversity in forests is strongly affected by forest management practices, such as clearcutting and aggregated retention. Therefore, the assessment of the effects of forest management on biodiversity is a major concern in forest ecology. In the present study, we aimed to characterize the effects of forest management practices, after one year, on the abundance, species richness, community composition, and functional groups of moths in forests. The moths were sampled in four different forest stands: three stands (clearcutting, aggregated retention, and no cutting) in a planted Japanese larch forest and one stand in a natural Mongolian oak forest. The results revealed that the moth communities changed in response to the changes in vegetation after the implementation of forest management practices, and clearcutting increased the abundance and species richness of herbivorous and warm-adapted species. The structure and function of moth communities were affected by the forest management practices such as clearcutting and aggregated retention, which were reflected by a decrease in community indices and change in moth community composition with changes in vegetation.

This study examined the effects of thinning intensities on carbon (C) storage of soil, forest floor and coarse woody debris (CWD) in Larix kaempferi stands, Korea. Two study stands were located in Gwangneung Experiment Forest (Stand 1: 31-40 years old) and Muju (Stand 2: 51-60 years old). These stands were thinned in 2011. Each stand was divided into three plots by different thinning intensities based on removed volume: no thinning (control, 0%), moderate thinning (M, 20%), and heavy thinning (H, 30%). The C storage of soil at 0-50 cm depth, forest floor, and CWD was measured in 2011. Total C storage of H plot was significantly higher than that of control plot and M plot in Stand 1 (control: 64.6 t C ha 71 , M: 62.2 t C ha 71 , H: 83.7 t C ha 71 ). A similar tendency was also found in Stand 2; total C storage of H plot was significantly higher than that of control plot and M plot (control: 137.8 t C ha 71 ; M: 138.0 t C ha 71 ; H: 169.6 t C ha 71 ). Initial effects of thinning intensities on C storage were analyzed as a part of the 10-year study, and we expect to determine the correct thinning intensity that optimizes C storage of soil, forest floor, and CWD by long-term monitoring of changes in C storage at this experimental site.

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