• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.319-325
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• 2013

This study describes the seasonal distribution of larvae, nymph, and adult life stages for 3 species of ixodid ticks collected by tick drag and sweep methods from various habitats in the Republic of Korea (ROK). Grasses less than 0.5 m in height, including herbaceous and crawling vegetation, and deciduous, conifer, and mixed forests with abundant leaf/needle litter were surveyed at United States (US) and ROK operated military training sites and privately owned lands near the demilitarized zone from April-October, 2004 and 2005. Haemaphysalis longicornis Neumann adults and nymphs were more frequently collected from April-August, while those of Haemaphysalis flava Neumann and Ixodes nipponensis Kitaoka and Saito were collected more frequently from April-July and again during October. H. longicornis was the most frequently collected tick in grass habitats (98.9%), while H. flava was more frequently collected in deciduous (60.2%) and conifer (57.4%) forest habitats. While more H. flava (54.1%) were collected in mixed forest habitats than H. longicornis (35.2%), the differences were not significant. I. nipponensis was more frequently collected from conifer (mean 8.8) compared to deciduous (3.2) and mixed (2.4) forests.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.1-10
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• 2007

This study was reviewed on the bioethanol production from biomass resources and feedstock supply in America. U.S. Department of Energy (USDE) and the u.s. Department of Agriculture USDA) are both strongly committed to expand the role of biomass as an energy source. They support biomass fuels and products as a way to reduce the need for oil and gas imports, to strengthen the nation's energy security and environmental quality. And it was envisioned a 20 percent replacement of the current U.S.transportation fuel consumption in 2030. Also it was reviewed policies to encourage the expanding of Bio-based fuel use to replace gasoline, such as Clean Air Act, Federal Clean Fuel Program and American Jobs Creation Act. In feedstock supply it was assumed forest biomass will be supplied in 368 million dry tons yearly and the agriculture derived biomass adopted by new technologies and land use change will be supplied in 998 million dry tons, including highly 818 million dry tons of lignocellulosic biomass such as perenial crops (hybrid trees, grasses) corn stover, other crop residues. This amount is 5 times to the amount from based current agricultural technology and crop land.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.187-194
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• 1985

This field experiment was carried out to determine the effects of thirteen different fertilizer levels of nitrogen(N), phosphorus($P_2O_5$) and potassium($K_2O$) on the content of crude protein, crude fiber, mineral constituents of product and tree growth forest pasture with 40-50% shading. The experiment was arranged as a randomized block design and performed in the suburban forest of Suweon in 1984. The results obtained are summarized as follows: 1. Crude protein content and total protein yield were higher in the plot of 28 and 42kg $N/_{10a}$, regardless of $P_2O_5\;and\;K_2O$ level, while those were the lowest in zero fertilizer and N-zero fertilizer plots. 2. The contents of lignin and silica were significantly low in the high N fertilizer level, and the contents of NDF, ADF, cellulose and hemicellulose were not affected by different fertilizer levels. However, the content of crude fiber tended to be low with high N, regardless of $P_2O_5\;and\;K_2O$. 3. The contents of N,K and $SiO_2$ of grasses were influenced by different fertilizer levels. However, those of P,Ca,Ma and Na showed little differences. 4. The recovery percentage of NPK was higher in the plot of standard fertilizer level with 28-20-24 kg/10a, and higher recovery percentage was observed in $K_2O$, followed by N and $P_2O_5$ in that order. 5. The growth of tree was increased as the level of N fertilizer was increased, but no such trend was noted by $P_2O_5\;and\;K_2O$ levels. 6. Crude protein, crude fiber, some mineral contituents of grasses, and growth of tree were influenced by N level, regardless of $P_2O_5\;and\;K_2O$. And the optimum fertilizer level of $N-P_2O_5-K_2O$ seemed to be 28-20-24 kg/10a for the production of grasses with higher quality and more yield in the forest.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.99-103
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• 2005

Actual vegetation map drown with the scale 1 to 100 and Alnus japonica population in Ja-neup and Woong-neup of the Mujechi moor were described in order to monitor long-termly and preserve permanently, where is a very rare Molinietea moor and a legally protected area. A total of 3036 plots of 5m $\times$ 5m were surveyed during summer 1996. Thiessen polygons of 1491 alder trees were derived from the plot data. Actual vegetation map was illustrated by 6 cover types such as needle spike-rush type, moor-grass type, alder-moor type, eulalia type, oak forest type, and exposed site. Molinia grasses native to the moor and Miscanthus grasses alien to the moor are reciprocally dominant. The area of Molinia grasslands was rapidly in decline and alder population size was dramatically in increase in the moor, particularly in Woong-neup. In Molinietea moor preservation more attention should be focused on the regulation of a nutrient rich soil from forest road and fire.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.55-61
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• 2013

This study was carried out to investigate the morphological and soil characteristics of Zoysia spp. native to South Korea. Samples [41 ecotypes of Zoysia japonica, 28 ecotypes of natural hybride between Z. japonica and Z. sinica (Junggi), 22 ecotypes of Z. sinica, and 8 ecotypes of Z. matrella] were collected in seashores, levee and summit of the rock in southern Korea. Variations in leaf width, plant height, leaf angle, length of leaf sheath, leaf trichome, stolon length, and seed shape were measured at collection sites and experimental plots. Among the entries, most of the measurements did not show any significant differences between natural and experimental plot except for leaf angle of Z. sinica and the number of seeds per spike of Z. matrella, which might be caused by different environmental conditions. Soil pH was 6.0 at the most of the collection sites. $Mg^+$ was 0.06-0.02 $cmol{_c}^+kg^{-1}$, $Mg^{2+}$ was 0.09-0.03 $cmol{_c}^+kg^{-1}$, and $K^+$ was 0.02-0.007 $cmol{_c}^+kg^{-1}$ at most zoysiagrasses growing soils.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.51-61
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• 2002

This study was conducted to investigate and compare species composition, stand structure, and growth pattern for two different sites in which silvopastoral system has been taking place. One site was the pasture area where a number of trees were removed and grasses were planted for cattle grazing, and the other site was the deciduous forest that has been established by ecological succession. The results were as follows: 1. Nine tree species were present equally in the pasture area and the deciduous forest. Of these species, seven tree species were growing in common for two sites. However, the species composition, including density and frequency, was varied by sites. 2. The number of stems per hectare in the pasture area was 71, and that in the deciduous forest was 1,433, having shown the big difference. It is estimated that, considering the growth rate, better grown trees were remained at the time of harvesting in 1996. 3. The growth of diameter, height, and basal area in the pasture area was superior to that in the nearby deciduous forest. In spite of higher values of diameter and height, the timber volume of pasture area per unit area was less than 15% of that in the deciduous forest. 4. Providing sufficient growing space, the pasture area supported higher values of diameter and height. The wider growing space also had influence on the expansion of crown of trees by the result of deliquescent growth pattern. From this point of view, more research would be needed to establish appropriate number of trees for silvopastoral system.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.347-359
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• 1996

This study was carried out to find the plant succession stage on highway cut-slopes. In order to analyze succession stage, plant survey with belt transect method was carried out in 1989 and 1995 at Joongbu-highway cut-slopes. The results could be summarized as follows ; The mean plant coverage of cut-slope was 78.3%. Plant coverage of Lower part area was higher than that of upper part area. Pioneer herb species on cut-slope were Miscanthus spp., Arundinella spp., Artemisia spp. etc., and pioneer woody species were Rubus crataegifolius, Robinia pseudoacacia, Pueraria thunbergiana, Pinus spp. etc. Also, among the introduced turf grasses, Eragrostis curvula is the pioneer species. Due to short of maintenance works, Zoysia japonica which has been planted by sodding work was found to decrease or diminish gradually. The ratio of pioneer stage plants, domestic and introduced herb species, seems to decrease, while the ratio of woody species which are advanced stage plants seems to increase. Maintenance works are needed to management and monitoring of plant succession on cut-slope, and use of herb and woody species will be effective.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.2
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• pp.79-86
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• 1987

This study was carried out to investigate the relationships and the variations of agronomic characteristics in the shoot and root part of grasses for the basic data of the development, the management and the utilization of pasture in the forest. This study was conducted with 0% (full sunlight), 25%, 50% and 75% of shading degrees after orchardgrass, timothy, perennial ryegrass, ladino clover and orchardgrass dominated mixture were planted on Aug. 25 in 1984. The results are summarized as follows: 1. Dry matter yield in 25% of shading was increased 3-1 7% compared with 0% (full sunlight), while 50 and 75% of shading were decreased 28-35% and 44-60%, respectively. Dry matter yield of timothy, perennial ryegrass and ladino clover were decreased 10, 8 and 33%, respectively, compared with orchardgrass, but there was little difference between orchard grass and mixture. 2. Root distribution by different shading degrees was the maximum at 25%, followed by 0, 50 and 75% of shading degrees. Root distribution among different species was the maximum at orchardgrass, followed by perennial ryegrass and timothy. Especially, root distribution of timothy was very little compared with different species. And significantly positive correlation was observed in the relationship between root weight and dry matter yield (r=0.8 102**). 3. The physiological activity of root by different shading degrees was declined by more shading. 4. The length and the percentage of blade by different shading degrees was an increase tendency by more shading. The length and the percentage of blade among different species was followed by timothy, perennial ryegrass and orchardgrass, in that order. And the correlation between the percentage of blade and dry matter yield was significantly negative.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.33-42
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• 1999

The objective of this study was to determine the optimal amount and the mixture ratio of seeds for revegetation species by investigating their growth characteristics. For the purpose of the experiments, 15 plants were chosen. In May of 1995 to September of 1998, the nursery seedbeds of the College of Agriculture and Life Sciences, Seoul National University were seeded with the mixtures of those species. Then, the nursery seedbeds were treated to investigate the effects of the amount of seeding, the amount of fertilizer, and the depth of soil on the growth characteristics. As the results of the experiments, it was found that the effects of all the treatments on growth of shoots and roots were significant in the early phase. For the expected number of seedlings more than 3,000 per square meter, many seedlings got withered to death while the survivors were suppressed to grow slow in the early stage due to the density problem.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.315-322
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• 2013

This study was carried out to establish a management program and soil restoration plan through analysis of soil properties and visitor questionnaires in Songrim in Hadong, Korea. Soil bulk density in Songrim was slightly higher in the closed-woodlands ($1.31g/cm^3$) than in the open-woodlands ($1.39g/cm^3$). Soil bulk density in the closed-woodlands was higher in walking trails ($1.74g/cm^3$) than in forest areas ($1.39g/cm^3$), while the rates of pore space were lower in walking trails (42.6%) than in forest areas (50.5%). The soil porosity were lower in the closed-woodlands (34.6%) than in the open-woodlands (42.6%). Soil strength in surface soil was slightly lower in the open-woodlands ($8.5kgf/cm^2$) than in the closed-woodlands ($10.5kgf/cm^2$). The content of organic matter, total nitrogen and exchangeable cations of the woodlands was low compared with the optimum nutrient content for tree growth in Korea forest soil. According to the survey, the objective of visiting in Songrim was to enjoy recreation and landscape views. To conserve pine forest ecosystems in Songrim, the respondents said that it needs to the implement of closed-woodland periods, the establishment of smoking free zone, and the prohibition of garbage throwing and alcohol including disciplinary rules and education. Also the respondents said that pine forest ecosystem in Songrim is relatively sound, but the woodlands require the intensive management to the ecosystem and the introduction of native understory vegetation, such as grasses under pine forest ecosystem. It is recommended to designate the rest-year forest for a proper period in all woodlands to restore the Songrim soil rather than the alternation application between the rest-year for three years or non-rest-year trails, and to open partially the walking trails across the woodlands after the period. In addition, the forest within the woodland is need to designate a long-term rest-year.