• Journal of Ecology and Environment
• /
• v.47 no.3
• /
• pp.103-116
• /
• 2023

Background: This study analyzed the physiological adaptations of a woody plant, Vitex rotundifolia, in Goraebul coastal sand dunes from May to September 2022. Environmental factors and physiological of plants growing under field and controlled (pot) conditions were compared. Results: Photosynthesis in plants growing in the coastal sand dunes and pots was the highest in June 2022 and July 2022, respectively. Chlorophyll fluorescence indicated the presence of stress in the coastal sand dune environment. The net photosynthesis rate (P_N) and Y(II) were highest in June in the coastal sand dune environment and July in the pot environment. In August and September, Y(NPQ) increased in the plants in the coastal sand dune environment, showing their photoprotective mechanism. Chlorophyll a and b contents in the pot plant leaves were higher than those in the coastal sand dune plant leaves; however, chlorophyll-a/b ratio was higher in the coastal sand dune plant leaves than in the pot plant leaves, suggesting a relatively high photosynthetic efficiency. Carotenoid content in the coastal sand dune plant leaves was higher in August and September 2022 than that in the pot plant leaves. Leaf water and soluble carbohydrate contents of the coastal sand dune plant leaves decreased in September 2022, leading to rapid leaf abscission. Diurnal variations in photosynthesis and chlorophyll fluorescence in both environments showed peak activity at 12:00 hour; however, the coastal sand dune plants had lower growth rates and Y(II) than the pot plants. Plants in the coastal sand dunes had higher leaf water and ion contents, indicating that they adapted to water stress through osmotic adjustments. However, plants growing in the coastal sand dunes exhibited reduced photosynthetic activity and accelerated decline due to seasonal temperature decreases. These findings demonstrate the adaptation mechanisms of V. rotundifolia to water stress, poor soils, and high temperature conditions in coastal sand dunes. Conclusions: The observed variations indicate the responses of the V. rotundifolia to environmental stress, and may reveal its survival strategies and adaptation mechanisms to stress. The results provide insights into the ecophysiological characteristics of V. rotundifolia and a basis for the conservation and restoration of damaged coastal sand dunes.

• Korean Journal of Environmental Biology
• /
• v.38 no.4
• /
• pp.554-562
• /
• 2020

Tremex fuscicornis (Siricidae), known as the xylophagous horntail, and Leucospis japonica (Leucospidae), known as the parasitoid wasp, are wood-boring wasps belonging to the order Hymenoptera. These insects are interesting sources of biological inspiration for the development of drilling mechanisms. To study the biomimicry aspects, the morphological characters of the ovipositor of T. fuscicornis and L. japonica were analyzed using a stereoscopic microscope, a field emission scanning electron microscope, and an optical microscope. There were many differences in the ovipositors between the two species, such as shape, length, surface structure, and arrangement of the teeth. Evenly arranged teeth were developed at the tip of both the dorsal valve and the ventral valve of the ovipositor of T. fuscicornis and looked like a rotating drill bit. In contrast, in L. japonica, the teeth, which looked like a saw, were found only on the ventral valve. Moreover, the tip of the ovipositor of T. fuscicornis was symmetrically divided into four parts, while that of L. japonica was divided into three parts having a 2:1:1 ratio. However, in the case of T. fuscicornis, after the 14th tooth, four parts melded into three parts maintaining a 2:1:1 ratio, and a dovetail joint was found on the horizontal cross-section of the ovipositor that allowed vertical movement for making a hole. These morphological differences of the ovipositor may be due to the insects' lifestyles and phylogenetic distance. Finally, zinc was commonly found at the tip of the ovipositors of both species, a probable result of ecological adaptation created by drilling wood.

• Animal Bioscience
• /
• v.37 no.8
• /
• pp.1474-1482
• /
• 2024

Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SID_CP = -664.181+8.484×DM (R² = 0.40), SID_Lys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R² = 0.66), SID_Thr = 39.916+7.843×EE (R² = 0.41), and SID_Trp = -361.588+4.891×DM+0.387×total starch (R² = 0.85). Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.1
• /
• pp.130-138
• /
• 2016

The use of antibiotics in aquaculture raises environmental and food safety concerns because chronic exposure of an aquatic ecosystem to antibiotics can result in the spread of antibiotic resistance, bioaccumulation of antibiotics in the organisms, and transfer of antibiotics to humans. In an attempt to overcome these problems, high-concentration red clay was applied as an alternative antibiotic against the following common fish pathogens: Aeromonas salmonicida, Vibrio alginolyticus, and Streptococcus equinus. The growth of A. salmonicida and V. alginolyticus was retarded by red clay, whereas that of S. equinus was promoted. Phase contrast and scanning electron microscopy analyses confirmed the attachment of red clay on cell surfaces, resulting in rapid gravitational removal and cell surface damage in both A. salmonicida and V. alginolyticus, but not in S. equinus. Different cell wall properties of grampositive species may explain the unharmed cell surface of S. equinus. Significant levels of oxidative stress were generated in only the former two species, whereas significant changes in membrane permeability were found only in S. equinus, probably because of its physiological adaptation. The bacterial communities in water samples from Oncorhynchus mykiss aquacultures supplemented with red clay showed similar structure and diversity as those from oxytetracycline-treated water. Taken together, the antibiotic effects of high concentrations of red clay in aquaculture can be attributed to gravitational removal, cell surface damage, and oxidative stress production, and suggest that red clay may be used as an alternative for antibiotics in aquaculture.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.19 no.6
• /
• pp.19-30
• /
• 2016

The projection of climate-related range shift is critical information for conservation planning of Korean fir (Abies koreana E. H. Wilson). We first modeled the distribution of Korean fir under current climate condition using five single-model species distribution models (SDMs) and the pre-evaluation weighted ensemble method and then predicted the distributions under future climate conditions projected with HadGEM2-AO under four $CO_2$ emission scenarios, the Representative Concentration Pathways (RCP) 2.6, 4.5, 6.0 and 8.5. We also investigated the predictive uncertainty stemming from five individual algorithms and four $CO_2$ emission scenarios for better interpretation of SDM projections. Five individual algorithms were Generalized linear model (GLM), Generalized additive model (GAM), Multivariate adaptive regression splines (MARS), Generalized boosted model (GBM) and Random forest (RF). The results showed high variations of model performances among individual SDMs and the wide range of diverging predictions of future distributions of Korean fir in response to RCPs. The ensemble model presented the highest predictive accuracy (TSS = 0.97, AUC = 0.99) and predicted that the climate habitat suitability of Korean fir would increase under climate changes. Accordingly, the fir distribution could expand under future climate conditions. Increasing precipitation may account for increases in the distribution of Korean fir. Increasing precipitation compensates the negative effects of increasing temperature. However, the future distribution of Korean fir is also affected by other ecological processes, such as interactions with co-existing species, adaptation and dispersal limitation, and other environmental factors, such as extreme weather events and land-use changes. Therefore, we need further ecological research and to develop mechanistic and process-based distribution models for improving the predictive accuracy.

• Journal of Ecology and Environment
• /
• v.41 no.8
• /
• pp.223-234
• /
• 2017

Background: Spatial structure of plants in a population reflects complex interactions of ecological and evolutionary processes. For dioecious plants, differences in reproduction cost between sexes and sizes might affect their spatial distribution. Abiotic heterogeneity may also affect adaptation activities, and result in a unique spatial structure of the population. Thus, we examined sex- and size-related spatial distributions of old-growth forest of dioecious tree Torreya nucifera in extremely heterogeneous Gotjawal terrain of Jeju Island, South Korea. Methods: We generated a database of location, sex, and size (DBH) of T. nucifera trees for each quadrat ($160{\times}300m$) in each of the three sites previously defined (quadrat A, B, C in Site I, II, and III, respectively). T. nucifera trees were categorized into eight groups based on sex (males vs. females), size (small vs. large trees), and sex by size (small vs. large males, and small vs. large females) for spatial point pattern analysis. Univariate and bivariate spatial analyses were conducted. Results: Univariate spatial analysis showed that spatial patterns of T. nucifera trees differed among the three quadrats. In quadrat A, individual trees showed random distribution at all scales regardless of sex and size groups. When assessing univariate patterns for sex by size groups in quadrat B, small males and small females were distributed randomly at all scales whereas large males and large females were clumped. All groups in quadrat C were clustered at short distances but the pattern changed as distance was increased. Bivariate spatial analyses testing the association between sex and size groups showed that spatial segregation occurred only in quadrat C. Males and females were spatially independent at all scales. However, after controlling for size, males and females were spatially separated. Conclusions: Diverse spatial patterns of T. nucifera trees across the three sites within the Torreya Forest imply that adaptive explanations are not sufficient for understanding spatial structure in this old-growth forest. If so, the role of Gotjawal terrain in terms of creating extremely diverse microhabitats and subsequently stochastic processes of survival and mortality of trees, both of which ultimately determine spatial patterns, needs to be further examined.

• Human Ecology Research
• /
• v.54 no.2
• /
• pp.141-154
• /
• 2016

This study examined the nature of multi-cultural families' housing problems living in South Korea. A qualitative research was conducted through in-depth interviews with immigrant women from three Southeast Asian countries. The subjects of this study were 15 married immigrants from the Philippine, Cambodia, and Vietnam living in Seoul. The major findings were as follows: firstly, reciprocity for the in-between person and environment: the preferred to blend into Korean society instead of making a community based on national origin. Secondly, intention to housing: all participants were passive about moving and the Vietnamese and Cambodians placed more importance on the family community than the Filipinas. Thirdly, meaning of housing and interaction: for the most important area in the house, the Vietnamese and Cambodians stated that rooms were for a couple and treated family space more importantly than Filipinas who pursuit personal comfort. Fourthly, housing adaptation process: adapting to climate difference between home countries and Korea was the biggest difficulty. Fifthly, residential satisfaction/dissatisfaction: mostly satisfied with housing facilities; however, they were dissatisfied with the number of rooms and house size due to a necessity for personal space. In conclusion, ideas implied from native country of married immigrants in multicultural families did not change significantly in preference of the current environment. The needs for an ethnic community was not great, because they seemed able to assimilate positively by living with a Korean husband and relatives. Gradual assimilation through a cultural acculturation process can be considered desirable.

• Korean Institute of Interior Design Journal
• /
• v.20 no.4
• /
• pp.54-62
• /
• 2011

Fast industrialization caused from Descartes' dichotomy has enormously developed our world, but endangered the ecosystem. In this study, the ecosystem aesthetics is not only a critique against existing growth-ideology and technical civilization, but also the art pursuing the life as an artistic state and achieving the dream for qualitatively different new future. Lao-tzu's Natural Beauty assumes that the adaptation to natural laws can lead every purpose's achievement. Based on such theoretical alternative, the earth construction as a medium for coexisting mankind, nature and construction interacts with the other objects through the natural affinity, the energy efficiency, the material generation. The earth construction provides the images of naivety, naturalness, folk as well as emotional stability in cultural terms. This study's direction and method are as follows. First, it researches the ecosystem aesthetics from the Taoism viewpoint, the alternative for environmental healing based on theoretical reviews about the ecosystem aesthetics. Second, it researches the earth construction's ecosystem aesthetic features and construction features from the low-tech aspect in continual construction genealogy. Third, it analyzes some cases targeting domestic buildings by drawing out expression methods and features through the connectivity of earth construction and ecosystem aesthetics. The earth construction lies between the heaven and the earth, but coexists in natural cycle. The earth construction caused from ecosystem aesthetics will be a future alterative, and various studies about its features and methods should be continued.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.10
• /
• pp.1483-1496
• /
• 2001

Small ruminants form an important economic and ecological niche in small farm systems and agriculture. Their current low level of contribution is dismal, and is not commensurate with the potential capacity for higher levels of production. The context for productivity enhancement and increased socio-economic contribution relates to large sizes of small ruminant populations; wide distribution across various agro-ecological zones and production systems; and diversity of breeds, where 66% of all goat and 57% of sheep breeds in Asia are found in China, India and Pakistan. The advantages and disadvantages of small ruminants over larger ruminants are enumerated with reference to adaptation and environment, small size, production systems and products and interactions with the environment. Discussion focuses especially on efficiency of meat production and niche markets for higher-priced goat meat, and inefficient marketing systems given an estimated 40-45% loss of income to farmers presently. Increasing the quantity of meat produced is related to live weight and the total number of animals at Slaughter, which in turn, depend on the total number of offsprings weaned and lifetime productivity. At the national level, priority attention is essential to build up numbers in concerted breeding programmes, selection for efficiency of reproduction and meat production, and improvements to make traditional markets and marketing systems to respond to the changing environmental and consumer preferences. Post-production systems are neglected and improvements are associated with collection, handling, marketing, slaughter facilities and consumer requirements. Potential opportunities to expand and benefit from integrating small ruminants into annual and perennial cropping systems remain largely unexplored. Important development imperatives include choice of species and better use of available breeds, appropriate production systems that match available feed resources, and linkages between production, products and by-products to markets. Affirmative action is necessary, backed by official policy support, institutional commitment and increased resource use, that can target poverty and directly benefit the poor, and shift subsistence production to a more market-oriented opportunity. These efforts together constitute the challenges for both the owners and producers of small ruminants in the immediate future, as also the will to accelerate increased productivity, improve their livelihoods and promote rural growth.

• Korean Journal of Ichthyology
• /
• v.26 no.4
• /
• pp.281-287
• /
• 2014

An olfactory organ in Scartelaos gigas, so-called mudskipper known as adaptation to an amphibious lifestyle, was investigated anatomically and histologically. S. gigas possessed the paired olfactory organ comprising respectively the one elongated canal and two nasal sacs, lacrimal and ethmoidal nasal sac. The sensory epithelium developed partly in the canal contained four distinct types of cells: (1) receptor cell with 3 to 4 cilia in number, (2) supporting, (3) basal, (4) mucus cell. The sensory epithelium was also of transitional layer as multi cellularity structure. The non-sensory epithelium had no sensory elements. The two nasal sacs possessed typically a lot of mucin droplets. These results might be considered that anatomical structure and histological characters of the olfactory organ showing in S. gigas is adapted to semi-aquatic life associated with its ecological habit and habitat.