The characteristics of animal distribution are determined by interactions between the resource requirements of animals and ecological factors. This study sought to evaluate the effects of diverse ...ecological factors on the home range and core area of red-backed voles (Myodes regulus) in a natural deciduous forest located on Mt. Gariwang, Pyeongchang and Jeongseon, South Korea. Our study focused on four types of ecological factors: topography, climate, cover, and demography. A total of 29 voles were radio-tracked from August to September 2021. Home range (95% utilization distribution; UD) and core area (50% UD) were calculated using the kernel density estimator (KDE). The home range (1659.49 m
) and core area (317.08 m
) were negatively affected by altitude. The lunar phase and temperature negatively and positively influenced the home range and core area, respectively. The home range was positively affected by understory vegetation, whereas the core area was not. The core area increased within microhabitats with a high density of conspecific individuals, with males having a larger home range (2006.19 m
) and core area (375.40 m
) than females (1043.13 m
and 213.39 m
, respectively). These findings provide a deeper understanding of the diverse ecological factors affecting the distributions of animals, especially small rodents.
Van der Waals heterostructures with two-dimensional magnets offer a magnetic junction with an atomically sharp and clean interface. This attribute ensures that the magnetic layers maintain their ...intrinsic spin-polarized electronic states and spin-flipping scattering processes at a minimum level, a trait that can expand spintronic device functionalities. Here, using a van der Waals assembly of ferromagnetic Fe3GeTe2 with non-magnetic hexagonal boron nitride and WSe2 layers, we demonstrate electrically tunable, highly transparent spin injection and detection across the van der Waals interfaces. By varying an electrical bias, the net spin polarization of the injected carriers can be modulated and reversed in polarity, which leads to sign changes of the tunnelling magnetoresistance. We attribute the spin polarization reversals to sizable contributions from high-energy localized spin states in the metallic ferromagnet, so far inaccessible in conventional magnetic junctions. Such tunability of the spin-valve operations opens a promising route for the electronic control of next-generation low-dimensional spintronic device applications.The authors investigate tunnelling magnetoresistance in Fe3GeTe2/hBN(WSe2)/Fe3GeTe2 magnetic tunnel junctions and report strong variations with bias including polarization reversals.
Understanding climatic effect on wildlife is essential to prediction and management of climate change's impact on the ecosystem. The climatic effect can interact with other environmental factors. ...This study was aimed to determine effects of climate and altitude on Siberian roe deer Capreolus pygargus activity in temperate forests of South Korea. We conducted camera trapping to investigate roe deer's activity level from spring to fall. Logistic regressions were used to determine effects of diel period, temperature, rain, and altitude on the activity level. A negative relationship was noted between temperature and the activity level due to thermoregulatory costs. Roe deer activity exhibited nocturnal and crepuscular patterns during summer and the other seasons, respectively, possibly due to heat stress in summer. In addition, the effect of temperature differed between high‐ and low‐altitude areas. In low‐altitude areas, temperature affected negatively the activity level throughout the study period. Conversely, in high‐altitude areas, temperature affected activity level only in summer and early fall. Lower temperatures in higher altitudes favoured roe deer activity, resulting in roe deer's preference towards higher altitude areas. However, roe deer's movement toward lower altitudes was observed in summer. Reduced heat stress by changing activity pattern allowed them to access lower altitude areas with greater resource availability during summer. This study revealed how roe deer activity varied across seasons and altitudes, considering the interactions among weather, microclimate and resource availability. It provides insight into how montane species adapt to various climatic conditions, and this could have important implications for wildlife management and conservation efforts.
The body mass of animals is directly or indirectly affected by multiple ecological factors. However, the effects of ecological factors on the body mass are controversial, and a comprehensive study ...dealing diverse ecological factors is rare. This study was performed to determine the effects of ecological factors on the body mass of small rodents in a natural deciduous forest located on Mt Gariwang, Pyeongchang and Jeongseon, South Korea from May 2019 to October 2020. We classified ecological factors into topographic, climatic, cover and demographic factors. Three forest‐dwelling small rodent species, striped field mouse Apodemus agrarius, Korean field mouse A. peninsulae and red‐backed vole Myodes regulus, were captured using the capture–mark–recapture method. The findings showed that the body mass of three rodent species was not regulated by topographic factors. In addition, a high ambient temperature resulted in a heavy body mass for A. agrarius and A. peninsulae, and the A. agrarius body mass was negatively affected by extreme rainfall. The body mass of each rodent species had a specific response to the cover factors: ground vegetation, understory vegetation or downed trees. The three species showed sexual dimorphism and two Apodemus species competed each other. This study reveals that ecological factors affecting body mass differ among species. Our findings contribute to enhancing the understanding of variation in the body mass of animals, particularly small rodents, in response to diverse ecological factors.
ABSTRACT Studies on the daily activity patterns of species can contribute to gaining an understanding of community ecology. During the warm seasons of the years 2019 to 2021, we used camera traps to ...monitor the activity patterns of water deer Hydropotes inermis, roe deer Capreolus pygargus, and Amur goral Naemorhedus caudatus in the Seoraksan and Jirisan National Parks, South Korea. We compared activity patterns among pairs of sympatric species in each area, as well as those of water deer and roe deer populations inhabiting the two parks. Overlaps in activity patterns were estimated based on kernel density function and overlap coefficient analyses, and activity pattern distributions were compared using Watson's two-sample test. We detected an overlap of the activity patterns of sympatric species and established that there were no significant differences in the distribution of activity patterns in the two areas. However, we detected differences between the Seoraksan and Jirisan sites with respect to the activity patterns of water deer particularly their patterns of nocturnal activity, which could be attributable to differences in community inter-specific interactions and food resources for water deer inhabiting the Seoraksan and Jirisan National Parks.
Pollination in flowering plants is initiated by germination of pollen grains on stigmas followed by fast growth of pollen tubes representing highly energy-consuming processes. The symplastic ...isolation of pollen grains and tubes requires import of Suc available in the apoplast. We show that the functional coupling of Suc cleavage by invertases and uptake of the released hexoses by monosaccharide transporters are critical for pollination in tobacco (Nicotiana tabacum). Transcript profiling, in situ hybridization, and immunolocalization of extracellular invertases and two monosaccharide transporters in vitro and in vivo support the functional coupling in supplying carbohydrates for pollen germination and tube growth evidenced by spatiotemporally coordinated expression. Detection of vacuolar invertases in maternal tissues by these approaches revealed metabolic cross talk between male and female tissues and supported the requirement for carbohydrate supply in transmitting tissue during pollination. Tissue-specific expression of an invertase inhibitor and addition of the chemical invertase inhibitor miglitol strongly reduced extracellular invertase activity and impaired pollen germination. Measurements of (competitive) uptake of labeled sugars identified two import pathways for exogenously available Suc into the germinating pollen operating in parallel: direct Suc uptake and via the hexoses after cleavage by extracellular invertase. Reduction of extracellular invertase activity in pollen decreases Suc uptake and severely compromises pollen germination. We further demonstrate that Glc as sole carbon source is sufficient for pollen germination, whereas Suc is supporting tube growth, revealing an important regulatory role of both the invertase substrate and products contributing to a potential metabolic and signaling-based multilayer regulation of pollination by carbohydrates.
Hovenia dulcis Thunb., known as Japanese raisin tree, is commonly found in East Asia. It has a long history as a food supplement and traditional medicine in Japan, China and Korea, but is little ...known and used in Western countries so far. This minireview summarizes traditional uses and current knowledge on the pharmacology and phytochemistry of H. duclcis and covers, in particular, literature from specialized Asian journals that are not readily accessible. Extracts from H. dulcis accelerate detoxification of ethanol, and possess hepatoprotective, antioxidative, antimicrobial and antidiabetic properties. Although the underlying molecular mechanisms are not fully understood, free radical scavenging and enhancement of ethanol catabolism have been reported.
ABSTRACT This study was conducted to clarify the effect of nutritional content on artificially supplied seed utilization of wintering birds in a mixed forest in South Korea. The dominant tree species ...in this forest were Japanese red pine (Pinus densiflora), Mongolian oak (Quercus mongolica), Japanese emperor oak (Quercus dentate). At the study site, we selected 6 plots and set up 3 feeders in each plot. The feeders were located 1.5 m above the ground and spaced 1 m apart. We selected 3 types of food resources (kidney beans, brown soybeans, and peanuts) based on their energy per 100 g. We supplied 200 g of each food type at the feeders. Feeders were recorded with a digital camera (HDR AS15, Sony, Tokyo, Japan) for 2 h. This was conducted 3 times per day. The videos were then analyzed to determine the frequency of visits, duration of stay at the feeder, frequency of pecking on food items, and number of consumed food items. Moreover, social behaviors were analyzed. In this study, we used peanuts as high-fat food type. Peanuts were consumed at the highest frequency by marsh tits (Poecile palustris), great tits (Parus major), and Eurasian nuthatches (Sitta europaea). In addition, the type of food, temperature, and metabolic energy requirement affected food utilization in marsh tits and great tits. In our study, some evidence was found that wintering birds in temperate zones prefer high-energy food items. Limited food availability during winter affects social hierarchies.
In higher plants, S
-basic region-leucine zipper (S
-bZIP) transcription factors fulfill crucial roles in the physiological homeostasis of carbon and amino acid metabolisms and stress responses. ...However, very little is known about the physiological role of S
-bZIP in cruciferous vegetables. Here, we analyzed the physiological function of S
-bZIP from
(BrbZIP-S) in modulating proline and sugar metabolism. Overexpression of
in
resulted in delayed chlorophyll degradation during the response to dark conditions. Under heat stress or recovery conditions, the transgenic lines exhibited a lower accumulation of H
O
, malondialdehyde, and protein carbonyls compared to the levels in transgenic control plants. These results strongly indicate that BrbZIP-S regulates plant tolerance against dark and heat stress. We propose that BrbZIP-S is a modulator of proline and sugar metabolism, which are required for energy homeostasis in response to environmental stress conditions.
Abstract
This study evaluated the effects of altitudinal gradients on small-rodent populations and microhabitat conditions. We selected three altitudinal bands: lowland, mid-land, and highland. We ...captured three small-rodent species, the striped field mouse (Apodemus agrarius), the Korean field mouse (A. peninsulae), and the red-backed vole (Myodes regulus). A. agrarius preferred microhabitats with dense ground vegetation and sparse mid-story vegetation, basal area, downed trees, and stone coverage. A. peninsulae utilized ground vegetation, overstory vegetation, and downed trees. M. regulus occupied microhabitats with abundant stone coverage and little ground vegetation coverage. Ground vegetation coverage was higher in the mid-land. The lowland was characterized by high understory vegetation, bulky downed trees, and high stone coverage. A. agrarius mostly occupied the mid-land, whereas A. peninsulae and M. regulus mainly inhabited the lowland. Our results show that each small-rodent species had its own strategy for utilizing the key habitat factors in altitudinally affected microhabitats and for reducing competition among the populations. This finding contributes to improving knowledge of the ecological altitudinal features of microhabitat conditions, as well as the altitudinal distributions and abundances of three small-rodent species.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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