• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.148-154
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• 1994

As a vegetative propagation method for ash species, which is a dioecism and a long cycle of fructification, cut-stem was soaked in water to induce adventitious sprouts, and 2-year-old ash seedling was cut in a nursery to induce adventitious sprouts. We obtained the 1,019 adventitious sprouts from branches of 101 plus trees througout the country. The mean ortet-age is 48. There is not a correlation between ortet ages and production of adventitious sprouts. These sprouts were placed in a cutting bed for rooting. Root ability varied with environmental factors of cuttings. The best rooting(87%) resulted from cutting performed in a vinyl-plastic greenhouse. Rooting was better on perlite+peat moss(2 : 1) medium than other media tested. The rooting ability was generally higher in 2-year-old ortet than plus tree ortet. In the root development of cuttings the non-container cuttings was better than container cuttings.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.33-41
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• 1986

This experiment was conducted to determine the influence of weed competition in sesame and the periods for weed control. Competition periods (days), for which sesame was seeded under transparent polyethylene film at May 15, were 10, 15, 30, 45, 60, 75, 90, and full growth season of sesame. Weed control periods (days), for which sesame was seeded under black polyethylene film at June 15, were 10, 15, 30, 45, 60, and full growth season of sesame. Dominant weeds were Ponulaca oleracea, Digitaria sanguinalis, Acalypha australis, L. Cyperus arnuricus, Arenaria aesrphllifolia, Cardamine flexucosa, Mollugo Stricta and Digitaria eschaemum. The number of weeds was maximum at the 30 days after planting. Broad leaf weeds were dominant than grass weeds, and then decreased the total number of weeds by the reason of major decrease of broad leaf weeds. However, the weight of weeds increased continuously. No weeds appeared until the 15 days after planting and the weight of broad leaf weeds was heavier than that of grass weeds until 45 days after planting. However, grass weeds were heavier than broad leaf weeds after 60 days after planting. The hazards of weeds on the growth and development appeared seriously from the 60 to 75 days after planting, but main yield reduction appeared from 30 days after planting. Therefore once more hand weeding should be practiced within 30 days after planting to minimize yield decrease. Serious hazards by weed growing appeared by removing black PE film after 15 to 30 days after planting in growth characteristics and 30 days later in grain yield. Leaf growth showed maximum from 45 to 60 days after planting and then decreased as compared with the continuous increase of stem and root in optimum planting, transparent PE film mulch and hand weeding. Leaf growth didn't show reducing in PE film mulch and weedy check but total weight of weeds increased and growth of sesame decreased as compared to PE film mulch and hand weeding. Leaf, stem and root growth of sesame, and weed weight under black PE film mulch showed same tendancy and lower growth of sesame as compared with optimum planting, transparent PE film mulch. Correlation between sesame yield and weeds weight were r =$ -0.874^{**}$ in the optimum planting and r = $-0.712^{**}$ in the late planting, so that the more weeds increase, the lesser sesame yield.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.316-338
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• 1988

To identify the physiological phenomena on the sudden wilting of japonica/indica crossed varieties, Pot experiment was carried out under the heavy N application with various levels of potassium in Japan. The results obtained are as follows. 1. Sudden wilting was occurred in both varieties used, Yushin and Milyang 23. The former showed a higher degree than the latter. 2. Sudden wilting was occurred into two types, one at early ripening stage and the other at late ripening stage. The former type was found in the field with low potassium supply and the latter was seemed to be related to varietal wilting tolerence. 3. By the investigation of concerning the effective tillering rate and the change of dry weight of each organ at the heading stage, it was inferred that the growth status from young panicle formation stage to heading stage were related to sudden wilting tolerence. 4. Manganese content at heading stage, ratio of Fe/Mn and Fe. Fe/Mn in stern at late ripening stage and $K_2$ O/N ratio of stem at harvesting stage were recognized as the specific factors in connection with sudden wilting. Mn content in the sudden wilting rice plant was already in creased remarkably at heading stage. In relation to root age and absoption characteristics of Mn, the senility of root before heading stage was inferred as the cause of increase the value of Fe/Mn or Fe. Fe/Mn. 5. The $K_2$ O/N ratio of culm at harvesting stage was lower in upper node than lower node in relation to sudden wilting. And it was well accordance with the fact that the symptoms of sudden wilting proceeded from upper leaf to lower leaf. These phenomenon was different from the usual one that the effect of potassium deficiency was more remarkable in lower node than upper node. 6. All varieties which have a condition of potassium deficiency have a high degree of nitrogen content of leaves at heading stage and the $K_2$ O/N ratio of each organ was low, Especialy, $K_2$ O/N ratio is much lower in sheath and culm than leaves.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.57-67
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• 2020

Pinus densiflora is the most widely distributed tree species in South Korea. Its ecological and socio-cultural attributes makes it one of the most important tree species in S. Korea. In recent times however, the distribution of P. densiflora has been affected by dieback. This phenomenon has largely been attributed to climate change. This study was conducted to investigate the responses of growth and physiology of P. densiflora to drought and nitrogen fertiliz ation according to the RCP 8.5 scenario. A Temperature Gradient Chamber (TGC) and CO₂. Temperature Gradient Chamber (CTGC) were used to simulate climate change conditions. The treatments were established with temperature (control versus +3 and +5℃; aCeT) and CO₂ (control: aCaT versus x1.6 and x2.2; eCeT), watering(control versus drought), fertilization(control versus fertilized). Net photosynthesis (P_n), stomatal conductance (g_s), biomass and relative soil volumetric water content (VWC) were measured to examine physiological responses and growth. Relative soil VWC in aCeT significantly decreased after the onset of drought. P_n and g_s in both aCeT and eCeT with fertiliz ation were high before drought but decreased rapidly after 7 days under drought because nitrogen fertilization effect did not last long. The fastest mortality was 46 days in aCeT and the longest survival was 56 days in eCeT after the onset of drought. Total and partial biomass (leaf, stem and root) in both aCeT and eCeT with fertiliz ation were significantly high, but significantly low in aCeT. The results of the study are helpful in addressing P. densiflora vulnerability to climate change by highlighting physiological responses related to carbon allocation under differing simulated environmental stressors.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.155-164
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• 2012

The chemical components in different parts of Artemisia argyi was investigated to provide industrial possibilities as functional foods The analysis result of proximate composition in leaves, stems and roots of Artenisia argyi was substantially as follows. The crude protein contents were 19.87, 6.14 and 5.68%, the crude lipid contents were 4.56, 1.30 and 1.20%, the crude fiber contents were 16.80, 29.70 and 29.45%, respectively. The major mineral components in Artemisia argyi were potassium, calcium and magnesium. Contents of potassium and calcium in leaves were 4,270.24 and 617.64 mg/100 g, respectively, they were more than double the contents of root. Sucrose and glucose as main free sugars were detected in the leaves and roots. However, glucose and fructose were identified in the stem. Total amino acids showed 17 amino acids. Contents of total amino acid in the leaves was the highest as 4,864.11mg/100g, and the stems and roots showed 1,953.99 and 1,601.73mg/100g, respectively. The major amino acids in the leaves and stems were proline(963.91 and 407.52mg/100g) and aspartic acid(577.38 and 299.17mg/100g), respectively. Glutamic acid(206.34mg/100g) and arginine(193.23mg/100g) were main amino acids in the roots. The major fatty acids in all parts were linoleic acid($C_{18:2}$), behenic acid($C_{22:0}$), and palmitic acid($C_{16:0}$). Eupatilin(35.0mg/100g) and jaceosidin (107.63mg/100g) as physiological compounds contents were higher in leaves than other parts.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.791-798
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• 2009

The role of forest and soil carbon under global climate change is getting important as a carbon sink and it is necessary to research on applicable forest models as well as in the field for a study of these dynamics. On this study, historical annual litter dataset as a major input data for the forest soil carbon model, Yasso was established using a dendrochronological reconstruction method, and the soil carbon dynamics of a Pinus densiflora forest in Gwangneung, Korea was simulated using Yasso. The amount of litter (needle, branch, stem and fine root) production, which was estimated using the dendrochronological method, has increased continuously from 1971 to 2006. Furthermore, there was no significant error between estimated and measured values of litter production (needle and branch) in 2006. The average of simulated soil carbon stock up to 30 cm depth was $46.30{\pm}4.28tCha^{-1}$, which accounted for 53% of carbon stock in trees of the forest, and had no significant difference and error with measured soil carbon stock. Under the climate change trend in Korea according to IPCC A1B scenario, it was estimated that the simulated soil carbon stock in the region would increase continuously from 1971 to 2041 and then decreased until 2100. Compared to the result of the scenario that there is no climate change, the soil carbon stock could be decreased up to 7.58% at 2100. It was inferred the dendrochronological reconstruction method and simulation of Yasso model are useful to estimate soil carbon dynamics of the natural P. densiflora forest. Follow-up researches, such as improvement of the dendrochronological method and Yasso model and their application and validation in various environment, are needed to produce more reliable results.

• Korean Journal of Agricultural Science
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• v.26 no.1
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• pp.58-64
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• 1999

The chemical composition and ruminal dry matter digestibilities of leaves, stems and roots of Aralia cordata Thunberg were determined and compared each other as a roughage sources for ruminants. The crude protein contents were higher for leaves(12.4%) than for leaves+stems (9.7%), stem(5.1%) and roots (3.8%) (P<0.05). The crude fat contents were higher for leaves (3.7%) than for roots (2.1%) and stems (1.3%) (P<0.05). The crude fiber contents were lower for roots (12.3%) than for leaves (15.0%), leaves+stems (27.7%) and stems (40.3%) (P<0.05), respectively. The contents of neutral detergent fiber were lower for leaves (30.2%) than for leaves+stems (42.0%), roots (50.8%) and stems (60.0%) (P<0.05), respectively. The contents of acid detergent fiber were lower for root(18.3%) than for leaves(21.4%). leaves+stems (37.5%) and stems (49.6%) (P<0.05), respectively. The calcium content of leaves(2.4%) were higher than those of stems and roots (0.97% and 0.69%), however the phosphorus contents were similar among leaves, stems and roots(0.25%, 0.19% and 0.35%). Ruminal dry matter digestibilities for 12, 24, 48 and 72hr of leaves(38.9%, 65.9%, 79.8% and 82.4%) and roots(38.9%, 59.8%, 77.6% and 78.5%) were higher than stems(31.1%, 44.1%, 49.5% and 52.6%). Furthermore the digestibilities of leaves were higher than those of alfalfa hay(37.4%, 48.8%, 67.8% and 71.8%) and although the digestibilities of stems which were the lowest among the parts were higher than those of acasia wood chip(12.6%, 18.2%, 21.6% and 24.3%).

• Economic and Environmental Geology
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• v.45 no.3
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• pp.255-264
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• 2012

The stabilization using limestone ($CaCO_3$) and steel making slag as the immobilization amendments for Cu and Pb contaminated farmland soils was investigated by batch tests, continuous column experiments and the pilot scale feasibility study with 4 testing grounds at the contaminated site. From the results of batch experiment, the amendment with the mixture of 3% of limestone and 2% of steel making slag reduced more than 85% of Cu and Pb compared with the soil without amendment. The acryl column (1 m in length and 15 cm in diameter) equipped with valves, tubes and a sprinkler was used for the continuous column experiments. Without the amendment, the Pb concentration of the leachate from the column maintained higher than 0.1 mg/L (groundwater tolerance limit). However, the amendment with 3% limestone and 2% steel making slag reduced more than 60% of Pb leaching concentration within 1 year and the Pb concentration of leachate maintained below 0.04 mg/L. For the testing ground without the amendment, the Pb and Cu concentrations of soil water after 60 days incubation were 0.38 mg/L and 0.69 mg/l, respectively, suggesting that the continuous leaching of Cu and Pb may occur from the site. For the testing ground amended with mixture of 3% of limestone + 2% of steel making slag, no water soluble Pb and Cu were detected after 20 days incubation. For all testing grounds, the ratio of Pb and Cu transfer to plant showed as following: root > leaves(including stem) > rice grain. The amendment with limestone and steel making slag reduced more than 75% Pb and Cu transfer to plant comparing with no amendment. The results of this study showed that the amendment with mixture of limestone and steel making slag decreases not only the leaching of heavy metals but also the plant transfer from the soil.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.99-108
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• 1987

Half-sib seeds and one-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains (pH 2.0, pH 3.0, pH 4.0 and pH 5.0) to examine the effects of acid rain on seed germination and seedling growth. The seeds were sown in a pot ($4500cm^3$) containing one of three different soils (nursery soil, mixed soil and sandy soil) and the seedlings were grown in the same pots as the seeds. Simulated acid rain was made by diluting sulfuric and nitric acid solution ($H_2SO_4$: $HNO_3$ = 3:1, V/V) with tap water and tap water (pH6.4), and treated by 5mm each time for three minutes during the growing seasons (April to October 1985 and April to August 1986). Acid rain treatments were done three times per week to potted seeds and seedlings by spraying the solutions. The seed germination, seedling growth and physiological characteristics of potted seedlings were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows: 1. Seed germination of Ginkgo biloba decreased significantly at pH 2.0 level in the field test, and also at the levels of both pH 2.0 and pH 3.0 in the laboratory test, compared to that at control. 2. For two-year-old seedlings, total, top and root dry weights per seedling were significantly different among the three soil types and among the levels of pH, and shoot growth was different only among the levels of pH. 3. For one-year-old seedlings, height and total and stem-branch dry weights per seedling were significantly different among the levels of pH.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.178-186
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• 2015

This study was carried out to determine the effects of environment controls (temperature and shading level) on germination responses and early growth of Allium thunbergii. Germination experiment was performed by pre-treatment (with low temperature and wetting treatments for 0, 20, 40 and 60 days) and temperature controls (5, 10, 15, 20, 25 and 30). And growth experiment was performed by containers (128 and 200 cavities containers) and shading level (full sunlight (control), 35%, 50% and 75% shading). Germination rate of A. thunbergii seeds were, 20 days of seed pre-treatment, the highest at $10^{\circ}C$ (81.7%) and the more temperature went up, the more germination rate went down. As a result of surveying container and shading treatments, the height, leaf area, leaf length, leaf aspect ratio (L/W) were higher under 50% shading of 128 (24.2cm, $2.76cm^2$, 22.3cm and 223.4, respectively) and 200 (22.6cm, $2.29cm^2$, 19.4cm and 190.5, respectively) cavities container. The root was grown well under full sunlight. Specially, fresh weight of shoot (leaves+stem) was higher under 50% shading of 128 (0.241g) and 200 (0.212g) cavities container. As a result of surveying the whole experiment, A. thunbergii seeds need to pre-treatment (with low temperature and wetting treatments for 20~40 days) for high germination rate. And it is judged better growth and higher yield by maintaining 50% shading of 200 cavities container.