• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.342-351
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• 1997

The objective of this study was to compare acid-neutralizing and buffering capacity of four tree species against soil acidification by acid rain. About 30-year-old forests composed of Pinus rigida, Alnus hirsuta, Quercus mongolica, and Liriodendron tulipifera in a provincial experimental forest located 15km east from Banwol Industrial Complex in Kyonggido were used in this study. Incident precipitation, throughfall and stemflow, and soil samples were collected from May to September, 1996 to analyze their pH and canon concentrations. Internal leaf pH, external acid neutralizing capacity(ENC), and buffering capacity index(BCI) of leaves were also determined. The incident precipitation showed an average pH of 4.56, with the percentage of acid rain incidents being 74%. The average soil pH of the study area was 4.15. The pH of throughfall and stemflow in all four species was higher than that of precipitation except that of the stemflow of Pinus rigida which showed a pH of 3.73. The throughfall of Liriodendron tulipifera showed the highest pH of 5.38. The pH of throughfall and stemflow showed a positive correlation and no correlation, respectively, with precipitations. The most abundant cation in precipitation was Ca. The canon concentraions in throughfall and stemflow decreased in the following order of K, Na, Ca, and Mg. Cation concentrations in stemflow were highest in Lirioendron tulipifera and lowest in Pines rigida. Nutrient leaching from above ground increased with decreasing pH of precipitation. The pH of stemflow showed a positive correlation with ENC and BCI. The highest values in ENC, BCI, soil pH, and soil cation concentrations were observed in Liriodendron tulipifera, while the lowest values were obtained in Pinus rigida, It was concluded that Liriodendron tulipifera had highest neutralizing capacity against acid rain, while Pinus rigida had the lowest capacity and even promoted acidification of soil.

• Korean Journal of Organic Agriculture
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• v.18 no.3
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• pp.363-375
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• 2010

Sustainable farming systems have remarkably increased in Korea due to the increase of environmental concerns caused by the conventional systems. This study was performed on eight-year-old 'Niitaka' pear tree s to investigate the effects of different organic fertilizers on soil chemical and microbial properties and leaf and bud developments. Treatment and applications included 10 kg of rice bran (RB), 10 kg of coffee bran compost (CBC), 10 kg of Chitin incubated compost (Micro keeper$keeper^{(R)}$, CIC), and 30 kg of the mixture of the RB, CBC, and CIC (RCC). Control received 60 g of NPK (16-11-12) chemical fertilizer. The organic fertilizers increased organic matter, nutrient concentrations such as P, K, Ca, and Mg, and microbial biomass in soils compared to the control. RCC had the greatest specific leaf weight (SLW), and the other treatments did not have a significant difference for the SL W. Leaf P and K concentrations were different among the treatments, but they were not affected by the amounts of the soil nutrients. No differences were observed in the leaf Ca and Mg concentrations in the treatments. Organic fertilizers had greater chlorophyll contents than the control but had similar flower bud characteristics to the control.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.779-786
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• 2012

Many farmers have been seeking alternatives to chemical fertilizer for successful organic fruit production. This experiment was carried out to investigate the replaceability of chemical fertilizer by cover crop and slurry composting biofiltration (SCB) liquid manure (LM) application in pear orchard. Three treatments were contained in this experiment; cover crop only and cover crop + LM treatment, and control (chemical fertilizer application). Dry weight and mineral contents of gramineous cover crops were significantly increased in LM-combined treatments than that of leguminous species. Bulk density of soil was decreased in rye + LM and hairy vetch + LM treatments, compared with each cover crop treatment. Soil pH was lowest in fertilizer treatment and soil nitrate content became similar between treatments after rainy season. Available soil phosphate was lower in cover crop and cover crop + LM treatmemts than control, but exchangeable Mg was higher. The mineral content and net assimilation rate of leaves showed no difference between the treatments. As a result, it is suggested that the application of SCB liquid manure in pear orchard managed by cover crops is desirable to maintain the productivity by improving soil physical properties and potential nutrient recovery.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1309-1314
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• 2003

Growth performance, nutrient digestibility and changes in caecal fermentation pattern was studied on four groups of 8 grower rabbits (soviet chinchilla) each, fed on diets containing 17 to 18% CP and $10.4-11.00MJ\;DE\;kg^{-1}$ feed. The complete diets contained mulberry leaves along with other feed ingredients at 0 (LH), 15 (ML15), 30 (ML30) and 45% (ML45) levels. In LH diet ground lucerne hay was added at 15% of the diet as roughage source. The diets were uniform in other nutritional parameters except the higher amount of hemicellulose (18.7 and 16.5%) in LH and ML15 diets. The performance of grower rabbits was better (p<0.05) on LH and ML15 diets in terms of twelve weeks weight (kg), total gain (g), average daily gain (ADG) and feed efficiency (%). Different levels of mulberry leaves in the diet did not influence the dry matter intake. Digestibility of nutrients for DM, OM, CP, NDF and energy was uniform in all the diets but the digestibility of CF, ADF and cellulose was higher (p<0.01) on ML15, ML30 and ML 45 diets. The hemicellulose digestibility was significantly higher (p<0.01) on LH (44.52%) and ML15 (48.00%) compared to ML30 (33.54%) and ML 45 (39.17%) diets. The nitrogen retention (% of intake) was higher (p<0.05) in LH and ML15 diets than ML30 and ML45 diets. The caecum weight as percent of intestine weight consistently increased (p<0.05) with increasing content of mulberry leaves in diets. Total nitrogen and $NH_3$-N was higher on LH and ML15 diets. It is concluded that incorporation of mulberry leaves can replace Lucerne hay in complete rabbit feed (15% in diet). Even at higher level i.e. 30 and 45% of the diet mulberry leaves based complete feed gave promising results.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1595-1604
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• 2012

Two studies were conducted to investigate the effects of anti-diarrhoeal herbs on growth performance, nutrient digestibility, and meat quality in pigs. In Exp 1, 150 weanling-growing piglets (average BW = $7.5{\pm}0.24$ kg, average age = $27{\pm}1$ d) were allotted into one of the five dietary treatments, including: i) CON, basal diet, ii) DP, basal diet+1 g/kg date pits, iii) JH, basal diet+0.5 g/kg Japanese-honeysuckle, iv) HCT, basal diet+1 g/kg houttuynia cordata thunb, and v) LE, basal diet+1 g/kg laquer tree extract. From wk 0 to 5, the JH, HCT and LE groups presented higher (p<0.05) ADFI, ADG and gain/feed ratio (G/F) than CON and DP groups. During wk 5 to 10, Pigs fed JH, HCT and LE diets indicated higher (p<0.05) ADG and ADFI than the pigs fed CON and DP diets. During the entire experimental period, a significant increase of ADG appeared in JH, HCT and LE (p<0.05). Pigs fed JH, HCT and LE diets got a higher (p<0.05) ADFI than the pigs fed CON and DP diets. Pigs fed diets with supplementations of herb additives revealled lower (p<0.05) score of diarrhea pigs during d 2 to d 6 compared with pigs fed CON diet. In Exp 2, 60 growing-finishing barrows and gilts (average BW = $54.10{\pm}1.20$ kg, average age = $54{\pm}3$ d) were allotted to three treatments: i) CON, basal diet; ii) YG, basal diet+1 g/kg yellow ginger and iii) HR, basal dietary+1 g/kg hoantchy root, respectively. From wk 0 to 5, Dietary supplementation of YG and HR enhanced (p<0.05) ADG. No difference was found between YG and HR treatments. During, wk 5 to 10, ADG also was observed higher in YG and HR treatments than CON group (p<0.05). Additional, YG had the highest ADG (p<0.05) among treatments. There was always an increase of ADG in YG and HR (p<0.05) through all periods. HR treatment showed a lower (p<0.05) score of diarrhoeal pigs on d 1and d 2 compared with CON treatment. Pigs fed YG and HR diets had a higher (p<0.05) longissimus muscle area (LMA) than pigs fed CON diet. In conclusion, anti-diarrhoeal herbs can improve growth performance, and prevent diarrhea incidence in pigs, it can also increase LMA in finishing pigs.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.438-445
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• 1999

The concentrations of some ions ($NO{_3}^-$, $Ca^{2+}$, $Mg^{2+}$, $NH{_4}^+$) in soil solution collected by zero tension lysimeter in mature Pinus rigida plantations in Goksung, Jeonranam-do were measured at two soil depths (10cm and 30cm) following various levels of cutting intensity treatment (uncut, $6m{\times}50m$, $10m{\times}50m$, $20m{\times}50m$ strip crearcutting) three times (July 6. July 30, and August 4) between June 20 and August 4 1998. The ion concentrations in the soil solution were significantly different among sampling times, while the concentrations were not different among cutting levels or sampling depths. The ion concentrations in the soil solution decreased in the order of $NO{_3}^-$ > $Ca^{2+}$ > $Mg^{2+}$ > $NH{_4}^+$ and the mean concentration was 3.60mg/L for $NO{_3}^-$, 1.7mg/L for $Ca^{2+}$, 0.5mg/L for $Mg^{2+}$, and 0.04mg/L for $NH{_4}^+$ respectively. These ion concentrations except for $NH{_4}^+$ ion were negatively correlated with the volume of collected soil solutions (r=-0.31~-0.41). The results suggest that the change of nutrient concentrations in the soil solution collected from the P. rigida plantations was related to the temporal input patterns of precipitation rather than the cutting intensity.

• The Journal of Engineering Geology
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• v.20 no.4
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• pp.401-407
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• 2010

This study was carried out to produce the characteristics of pollutant loads caused by a cherry tree plot as a nonpoint sources(NPS) unit in agricultural areas. The relationship between rainfall and runoff didn't show a good coefficient with 0.5. Despite precipitation amount was less than 20 mm, runoff occurred with $0.5\;m^3$ because of high rainfall intensity of 8.8 mm/hr. In contrast, runoff was not occurred when precipitation amount was 47.4 mm in one case. In that case the primal effect on runoff was not precipitation amount. Correlation between load of pollutants such as BOD, COD, TN and TP and runoff' volumes showed significantly positive values which were more than r = 0.92 for all pollutants except SS(r = 0.71). SS could be a proper factor for estimating pollutant loads of BOD, COD, TN and TP because of a high correlation more than r = 0.73 between SS load and pollutant loads of BOD, COD, TN and TP. Both Organics and nutrient pollutants could be reduced if we control SS in runoff. The highest concentration of TN was detected in the event which was affected by fertilization activities directly. Therefore fertilization must be considered as a function of impact parameters on TN load in agricultural areas.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.63-70
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• 2012

Larix kaempferi and Betula costata seedlings were grown under an elevated temperature ($27^{\circ}C$) for four weeks to understand initial changes on physiological characteristics caused by temperature rising in connection with global warming. At the end of the treatment, growth performance, leaf pigment content, antioxidative enzyme activities and malondialdehyde (MDA) content were measured and analyzed. Relative growth rates of the height of two tree species grown under elevated temperature ($27^{\circ}C$) were lower than those of control ($24^{\circ}C$) and dry weights of leaves, stems and roots were also reduced at higher temperature. Particularly, the root growth reduction of two tree species increased markedly at $27^{\circ}C$ over the study period, which increased the ratio of shoot to root. Under higher temperature, leaf pigment contents decreased, whereas anti-oxidative enzyme activities such as ascorbate peroxidase (APX) and catalase (CAT) increased as compared with the control. But MDA content was not affected by elevated temperature. In conclusion, the elevated temperature leads to root growth reduction, restriction of nutrient uptake from soil and the reduction of leaf pigment contents, which can inhibit the aboveground growth. In addition, higher temperature might act as a stress factor that causes growth reduction through the increase of energy consumption during a growth period.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.154-158
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• 2019

BACKGROUND: 'Shiranuhi' mandarin is a major cultivar among all late ripening type of citrus, and is widely cultivated in Korea. However, many farmers have reported scion root problems in their orchard resulting in reduced flowering and fruiting. It is necessary that the physiology of scion-rooted 'Shiranuhi' mandarin trees is further understood. METHODS AND RESULTS: This experiment was conducted to understand the growth response and physiology of scion-rooted 'Shiranuhi' mandarin hybrids. In our study, 'Shiranuhi' mandarin trees were divided into two groups: trees without scion roots (control) and trees with scion roots. The experiment was conducted in Seogwipo of Jeju, with ten replicates for each group. Growth of trees with scion roots was more vigorous and the trees were taller than the controls. Tree height and trunk diameter of scion-rooted trees were significantly higher than those of control trees. Exposed length of rootstocks of scion-rooted trees was significantly lower (by about 2 cm) than that of control trees (8.6 cm). In terms of root nutrition, carbon contents of scion-rooted trees was significantly lower than that of control trees, but nitrogen and potassium concentrations in scion roots were significantly higher than those in control roots. CONCLUSION: Based on the results, we infer that growth of scion-rooted trees was very vigorous and the content of nitrogen in these roots was higher than that in the control tree roots. Thus, the carbon/nitrogen ratio of scion roots was significantly lower than that of the control roots.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.422-432
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• 2022

Soil and micro-climatic environmental monitoring was conducted to evaluate the factors causing tree growth impediments at the Baekdudaegan ecological axis restoration project site. As a result, it was found that the nutrient supply was insufficient in the restoration project site due to the lack of organic matter, total nitrogen and cation exchange capacity of the soil compared to the surrounding forest. After the completion of the restoration, the soil moisture in the autumn decreased more than 7 times faster than that of the surrounding forest, and it was evaluated that the soil moisture was significantly low due to the lack of silt and clay content. In the case of the restoration site, the annual potential evapotranspiration was analyzed to be 975mm, which is approximately two times higher than that of the surrounding forest. The soil moisture of the restoration site in the summer decreased rapidly during the daytime when the amount of insolation increased and this was found to be strongly influenced by the increase in potential evapotranspiration. In order to improve the above factors affecting the tree growth at the Baekdudaegan ecological axis restoration project site, it is necessary to induce the smooth supply of nutrients and water to plants by improving physical proprieties and cation exchange capacity, i.e., using litterfall, humus soil, soil conditioner and organic fertilizer. The results of this study are expected to serve as basic data for the design, construction, and management of ecological axis restoration projects in the future.