• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.04a
• /
• pp.49-49
• /
• 2019

본 연구는 대한민국 매실나무 열매의 특성평가를 위하여 청매실의 무게를 대, 중, 소로 구분하여 발효액의 수율, 당도, 산도 및 당산비를 조사하였고, 청매실과 황매실의 발효액 특성을 비교하였다. 발효액의 수율은 82~132%의 범위로 매우 넓었으며, 대 > 중 > 소의 순으로 적은 경향을 보였다. 당도는 55.4~59.1%의 범위이었으며, 무게에 따른 차이는 나타나지 않았다. 산도는 1.73~2.71%의 범위이었으며, 무게에 따른 차이는 나타나지 않았다. 당산비는 20.6~31.3의 범위로 매우 크게 나타나 자원의 다양한 특성이 존재함을 나타내었으며, 무게에 따른 차이는 나타나지 않았다. 무게에 따른 발효액 수율, 당도, 산도 및 당산비는 처리간 차이를 나타내지 않았으나 전체적인 자원간에는 큰 차이를 나타내어 다양하였다. 발효액의 변이계수는 당산비 > 산도 > 당도 > 수율의 순이었다. 청매실과 황매실의 발효액은 수율의 경우 황매실이 높았고, 당도와 산도는 청매실이 높았으며, 당산비는 차이가 없었다.

• Environmental Engineering Research
• /
• v.24 no.3
• /
• pp.484-494
• /
• 2019

This paper presents a preliminary investigation of the optimum nutrients combination required for bioremediation of spent-engine oil contaminated soil using Box-Behnken-Design. Three levels of cow-manure, poultry-manure and inorganic nitrogen-phosphorus-potassium (NPK) fertilizer were used as independent biostimulants variables; while reduction in total petroleum hydrocarbon (TPH) and total soil porosity (TSP) response as dependent variables were monitored under 6-week incubation. Ex-situ data generated in assessing the degree of biodegradation in the soil were used to develop second-order quadratic regression models for both TPH and TSP. The two models were found to be highly significant and good predictors of the response fate of TPH-removal and TSP-improvement, as indicated by their coefficients of determination: $R^2=0.9982$ and $R^2=1.000$ at $p{\leq}0.05$, respectively. Validation of the models showed that there was no significant difference between the predicted and observed values of TPH-removal and TSP-improvement. Using numerical technique, the optimum values of the biostimulants required to achieve a predicted maximum TPH-removal and TSP-improvement of 67.20 and 53.42%-dry-weight per kg of the contaminated soil were as follows: cow-manure - 125.0 g, poultry-manure - 100.0 g and NPK-fertilizer - 10.5 g. The observed values at this optimum point were 66.92 and 52.65%-dry-weight as TPH-removal and TSP-improvement, respectively.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.3 no.3
• /
• pp.129-138
• /
• 2022

Reintroduction programs have been promoted across the world to recover and rehabilitate endangered birds through ex situ captive breeding and releasing to the nature. The ultimate aims of these reintroduction programs are recovery of sustainable populations in natural habitats. To ensure the success of the reintroduction programs, it is necessary to examine the followings in order to increase the success rate of releasing along with the development of captive breeding techniques: 1) Adequate habitat provision, 2) adaptability of captive-bred individuals, 3) survivability of released individuals, and 4) social interest and will. Before releasing captive-bred individuals, it should be reviewed whether there are habitats in which the limiting factor is removed, and assessed their long-term safety. The quantity and quality of the released individuals must be considered to increase the chances for mate selection, maintain genetic diversity, and acquire the ability to adapt to the wild. The release method must be decided in consideration of characteristics of the target habitats and individuals, and rational means such as careful observation, evaluation, and feedback must be provided throughout the release process. For the long-term success of recovery projects, social awareness, sustainable support, and related experts are needed. Satisfying these criteria can help to increase the success rates of reintroduction programs. For the bird reintroduction program in the future, the feasibility of the methods and procedures must be closely reviewed before starting.

• Journal of Forest and Environmental Science
• /
• v.39 no.2
• /
• pp.65-72
• /
• 2023

The endangered species of Cyathea spinulosa (tree ferns) are among the least concerned ferns of Nepal that bring threats to them and their habitat. A way to reduce such threats is by maintaining a database of species' whereabouts and generating a scientific understanding the habitat preferences. This will eventually help in the formulation of conservation plans for the species. This research aimed to characterize the suitable habitat of C. spinulosa by enumerating the location of species in the Panchase Forests of central Nepal. The statistical index method was applied to relate the occurrence locations of species with various environmental factors for the development of indices. The suitable habitat of C. spinulosa (more and most suitable categories) covered 119 km² and accounted for 43% of the total area studied. 74.4% of occurrence locations of C. spinulosa were recorded from these habitats. The habitat characteristics suitable for C. spinulosa were: proximity to streams (high moisture), land covered by forested area (shady area), mid-elevations of hills about 1,000 m to 2,000 m (sub-tropical climate), slope gradient of 20° to 40° (steep slopes), and northern to eastern aspects. These habitat characteristics could be considered for in-situ protection of tree ferns and designating the conservation plots.

• ALGAE
• /
• v.37 no.4
• /
• pp.301-316
• /
• 2022

The red alga Compsopogon caeruleus can generally be found in tropical and subtropical waters worldwide. In addition to its natural habitats, this species may be found in waters that receive abnormally hot water, e.g., from powerhouses. To date, the presence of C. caeruleus has not been observed in thermally polluted lacustrine ecosystems in Poland, which has a moderate climate. The thalli of this red alga were found growing on Vallisneria spiralis in Lichenskie Lake. Importantly, this paper presents a previously unknown relationship between the temperature (20, 25, 30, 35, and 40℃) and oxygen requirements of C. caeruleus (based on ex situ measurements of O₂ consumption by thalli). Surprisingly, 35℃ can be the optimum temperature for C. caeruleus, and this temperature is higher than the values reported by some previous thermal analyses by approximately 10℃. Additionally, we reviewed and mapped the distribution of this nonnative and mesophilic red alga in natural / seminatural water ecosystems in Europe. Finally, we propose that the occurrence of C. caeruleus mature thalli can be a novel, simple and easy-to-recognize bioindicator of artificially and permanently heated waters in moderate climate zones by a regular discharge of postindustrial water.

• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.2
• /
• pp.105-118
• /
• 2015

This study was carried out to investigate the effects of profile disturbance with different artificial accumulation history on physico-chemical properties of soil under plastic film house. The investigations included soil profile description using soil column cylinder auger F10cm x h110cm, in situ and laboratory measurements of soil properties at five sites each at the cucumber (Site Ic ~ Vc) and grape (Site Ig ~ Vg) plastic film houses with artificial soil accumulation. The sites except sites Ic, IVc, IVg and Vg, belong to ex-paddy area. The types of accumulates around root zone included sandy loam soil for 3 sites, loam soil for 1 site, saprolite for 2 sites, and multi-layer with different accumulates for 3 sites. Especially, Site IIg has mixed plow zone (Ap horizon) with original soil and saprolite, whereas disturbed soil layers of the other sites are composed of only external accumulates. The soil depth disturbed by artificial accumulation ranged from 20 cm, for Site IIg, to whole measured depth of 110 cm, for Site IVc, Vc, and Site IVg. Elapsed time from artificially accumulation to investigation time ranged from 3 months, Site IIc, to more than 20 years, Site Vg, paddy-soil covering over well-drained upland soil during land leveling in 1980s. Disturbed top layer in all sites except Site Vg had no structure, indicating low structural stability. In situ infiltration rate had no correlation with texture or organic matter content, but highest value with highest variability in Site IIIc, the shortest elapsed time since sandy loam soil accumulation. Relatively low infiltration rate was observed in sites accumulated by saprolite with coarse texture, presumably because its low structural stability in the way of weathering process could result in relatively high compaction in agro-machine work or irrigation. In all cucumber sites, there were water-transport limited zone with very low permeable or impermeability within 50 cm under soil surface, but Site IIg, IIIg, and Vg, with relatively weak disturbance or structured soil, were the reverse. We observed the big change in texture and re-increase of organic matter content, available phosphate, and exchangeable cations between disturbed layer and original soil layer. This study, therefore, suggest that the accumulation of coarse material such as saprolite for cultivating cash crop under plastic film house might not improve soil drainage and structural stability, inversely showing weaker disturbance of original soil profile with higher drainage.

• Korean Chemical Engineering Research
• /
• v.45 no.4
• /
• pp.311-318
• /
• 2007

Soil contamination in Korea has been accelerated every year. Because of their persistence and cumulative tendency in the environment, soil contaminants have potential long-term environmental and health concerns and it is estimated to cost enormous expense for clean-up. Korea government has legislated the law on conservation of soil environment in mid 1990s, and managed and treated hazardous wastes in contaminated sites as a remediation policy since then. Soil remediation technologies are classified into in-situ/ex-situ or biological/physico-chemical/thermal processes according to applied places or treatment methods, respectively. In Korea, clean-up of polluted sites has been mostly carried out at military areas, railroad-related sites and small-scale oil spilt sites. For these cases, in-situ remediation technologies such as soil vapor extraction (SVE) and bioventing were mainly used. In recent days, an environmental-friendly soil remediation emerged as a new concept - for example, a new soil remediation process using nanotechnology or molecular biological study and an integrated process which can overcome the limitation of individual process. To have better applicability of remediation technologies, comprehensive understandings about the pollutants and soil characteristics and the suitable techniques are required to be investigated. Above all, development of environmental technologies based on the sustainability accompanied by public attention can improve soil environment in Korea.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.08a
• /
• pp.131-131
• /
• 2013

A single-layer graphene has been uniformly grown on a Cu surface at elevated temperatures by thermally processing a poly(methyl methacrylate) (PMMA) film in a rapid thermal annealing (RTA) system under vacuum. The detailed chemistry of the transition from solid-state carbon to graphene on the catalytic Cu surface was investigated by performing in-situ residual gas analysis while PMMA/Cu-foil samples being heated, in conjunction with interrupted growth studies to reconstruct ex-situ the heating process. The data clearly show that the formation of graphene occurs with hydrocarbon molecules vaporized from PMMA, such as methane and/or methyl radicals, as precursors rather than by the direct graphitization of solid-state carbon. We also found that the temperature for vaporizing hydrocarbon molecules from PMMA and the length of time the gaseous hydrocarbon atmosphere is maintained, which are dependent on both the heating temperature profile and the amount of a solid carbon feedstock are the dominant factors to determine the crystalline quality of the resulting graphene film. Under optimal growth conditions, the PMMA-derived graphene was found to have a carrier (hole) mobility as high as ~2,700 cm2V-1s-1 at room temperature, superior to common graphene converted from solid carbon.

• Journal of Soil and Groundwater Environment
• /
• v.11 no.6
• /
• pp.8-17
• /
• 2006

Laboratory scale experiments were performed to investigate the removal efficiency of the in-situ chemical oxidation method and the air-sparging method for diesel contaminated soil and groundwater. Two kinds of diesel contaminated soils (TPH concentration : 2,401 mg/kg and 9,551 mg/kg) and groundwater sampled at Busan railroad station were used for the experiments. For batch experiments of chemical oxidation by using 50% hydrogen peroxide solution, TPH concentration of soil decreased to 18% and 15% of initial TPH concentration. For continuous column experiments, more than 70% of initial TPH in soil was removed by using soil flushing with 20% hydrogen peroxide solution, suggesting that most of diesel in soil reacted with hydrogen peroxide and degraded into $CO_2$ or $H_2O$ gases. Batch experiment for the air-sparging method with artificially contaminated groundwater (TPH concentration : 810 mg/L) was performed to evaluate the removal efficiency of the air-sparging method and TPH concentration of groundwater decreased to lower than 5 mg/L (waste water discharge tolerance limit) within 72 hours of air-sparging. For box experiment with diesel contaminated real soil and groundwater, the removal efficiency of air-sparging was very low because of the residual diesel phase existed in soil medium, suggesting that the air-sparging method should be applied to remediate groundwater after the free phase of diesel in soil medium was removed. For the last time, the in-situ box experiment for a unit process mixed the chemical oxidation process with the air-sparging process was performed to remove diesel from soil and groundwater at a time. Soil flushing with 20% hydrogen peroxide solution was applied to diesel contaminated soils in box, and subsequently contaminated groundwater was purified by the air-sparging method. With 23 L of 20% hydrogen peroxide solution and 2,160 L of air-sparging, TPH concentration of soil decreased from 9,551 mg/kg to 390 mg/kg and TPH concentration of groundwater reduced to lower than 5 mg/L. Results suggested that the combination process of the in-situ hydrogen peroxide flushing and the air-sparging has a great possibility to simultaneously remediate fuel contaminated soil and groundwater.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.2
• /
• pp.230-236
• /
• 2018

Objective: Two ex vivo experiments were conducted to verify the effect of barley grain (Nusrat cultivar) treated with alkaline compounds (AC) including alum, ammonium, and sodium hydroxide or cation-exchanged organic extracts (OE) prepared from alfalfa hay, sugar beet pulp and Ulva Fasciata, on extent and digestion of starch. Methods: In the first study, the in vitro first order disappearance kinetic parameters of dry matter (DM), crude protein (CP) and starch were estimated using a non-linear model ($D_{(t)}=D_{(i)}{\cdot}e^{(-k_d{\cdot}time)}+I$, where: $D_{(t)}$ = potentially digestible residues at any time, $D_{(i)}$ = potentially digestible fraction at any time, $k_d$ = fractional rate constant of digestion (/h), I = indigestible fraction at any time). In the second experiment, the ruminal and post-ruminal disappearance of DM, CP, and starch were determined using in situ mobile nylon bag. Results: Barley grains treated with alum and alfalfa extract had a higher constant rate of starch digestion (0.11 and 0.09/h) than others. Barley grain treated with OE had a higher constant rate of CP digestion and that of treated with AC had a higher constant rate of starch digestion (0.08 and 0.11/h) compared with those of the other treatments. The indigestible fraction of starch treated with alum and sugar beet pulp extract was higher than that of the control group (0.24 and 0.25 vs 0.21). Barley grain treated with AC and OE had significant CP disappearance in the rumen, post-rumen and total tract, and also starch disappearance for post-rumen and total tract compared with the untreated (p<0.001). Conclusion: This study demonstrated that AC and OE might have positive effects on the starch degradation of the barley grain. In addition, treating barley grain with alum and sugar beet pulp extract could change the site and extend digestion of protein and starch.