• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.327-334
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• 2014

Light intensity is one of the most important requirements for plant growth, affecting growth, development, survival, and crop productivity. Sunlight is the main energy source on Earth which is energy used by photosynthesis to convert light energy to chemical energy. In this study, the light use efficiency and photosynthetic characteristics of high-quality rice cultivars were evaluated after shading on ripening stage. For the study, we treated of three levels of shade (0, 50 and 70%) on rice at ripening stage and two levels of nitrogen (9 and 18 kg/10a) used three high yielding rice cultivars, such as Boramchan, Hopum, and Honong. The shade was given for the respective plots from heading up to harvesting. We were performed to determine growth survey, SPAD and chlorophyll fluorescence every 10 days interval after shading on ripening stage. At harvest stage, grain yield and yield components were determined. Results of analysis of the results representing the maximum photosynthetic efficiency of PSII, Fv/Fm, and SPAD were decreased by depending on the time at full sunlight. But shade treatments were not changed and a significant difference among cultivars did not appear. Compared with the full sunlight, shade treatments significantly delayed ripening rate and decreased rice quality of cultivated rice. Therefore, rice yield, can be reduced in proportion to the shading density is apparent, the rate of decrease was not observed difference between varieties, when protected from light 70%, and decreased to less than 50%. The adverse effects of low light intensity on the yield and yield components were not able to significantly minimize by the nitrogen level.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1421-1431
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• 2013

This study was conducted for clarifying distribution and characteristics of marshy Ericaceae plants on Mt. Changbai in China. The marshy Ericaceae plants in wetland of Mt. Changbai were investigated on about 1400 m altitude. This region is various developmental wetlands and vegetation mixture of needle-leaf trees and broad-leaf trees. This region also is start point of the coniferous forest zone in Mt. Changbai. As results of these researches, L. palustre var. diversipilosum and L. palustre var. decumbens populations were investigated in Larix olgensis var. amurensis community. R. lapponicum subsp. parvifolium var. parvifolium community appeared as a typical community. Environmental conditions of L. palustre var. diversipilosum and L. palustre var. decumbens populations' habitats are more soil humidity and shade condition. R. lapponicum subsp. parvifolium var. parvifolium community habitat, however, has more deposits and humidity condition. Therefore when the plants were cultivated, we should recognize the growth condition such as maintenance of humidity and control deposits. The flora of marshy Ericaceae species habitats was investigated as 28 families, 49 genera, 45 species, 14 variety, 1 forma, 1 sub-species, and total 61 taxa.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.207-211
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• 2008

We investigated the leaf demography of a temperate woody liana, Akebia trifoliata, in a temperate forest in Japan, Akebia is semi-evergreen: some leaves are shed before winter, while others remain through the winter. Previous studies of semi-evergreen species found that variation in leaf life span was caused by variation in the timing of leaf emergence, Leaves that appeared just before winter over-wintered, while leaves appearing earlier were shed, However, it is unclear whether leaves of the same cohort (i.e., leaves that appear at the same time within a single site) show variation in life span under the effect of strong seasonality. To separate variation in life span among the leaves in each cohort from variation among cohorts, we propose a new method - the single leaf diagram, which shows the emergence and death of each leaf. Using single leaf diagrams, our study revealed that Akebia leaves within a cohort showed substantial variation in life span, with some over-wintering and some not. In addition, leaves on small ramets in the understory showed great variation in life span, while leaves on large ramets, which typically reach higher positions in the forest canopy, have shorter lives, As a result, small ramets were semi-evergreen, whereas large ramets were deciduous, The longer lives of leaves on small ramets can be interpreted as a shade-adaptive strategy in understory plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.3
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• pp.73-77
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• 2004

The purpose of this study was to improve the ornamental value of Perilla frutescens var. acuta. The growth of Perilla frutescens var. acuta was significantly varied as according to light intensities. The plant height, crown width, petiole length, leaf length, leaf width, stem diameter, and chlorophyll content were the greatest with 30% shade treatment. All of growth characteristics decreased as increasing shading levels. The anthocyanin contents also decreased with 70% shading level. The leaf color turned from dark purplish red to deep yellowish green, and the growth rate and ornamental value were the lowest with 70% shading condition.

• Journal of Korean Society of Rural Planning
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• v.8 no.3 s.17
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• pp.49-57
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• 2002

The purpose of this study is to present a new orientation for the residential culture that can meet the shifting demands of modern people as their attitudes toward life change. One of the rural regions that has lately attracted considerable attention, Wonsam-myun, Yongin city, is selected as the residence zone to develop a housing complex. In this study, a new housing complex is designed to supplement the defects of existing housing complexes by making the utmost use of the merits that Wonsam-myun as a residential environment can offer. The major findings of this study can be summarized as follows: 1. To present a new Korean model, yellow soil houses and traditional trees were used to utilize Korea's traditional landscape beauty in the construction and landscape aspect, instead of imitating indiscreetly foreign styles in which most newly developed housing complexes were built. 2. To provide convenience to prospective residents, a package sales scheme covering from lot purchase to building permit was adopted. 3. As for the planting plan, existing plants was preserved as much as possible to keep harmony with new plants. In selecting plant types, a traditional method that emphasizes on the visual effects of aesthetic plants and shade trees with the change of seasons and plants various kinds of plants according to directions was adopted. 4. Each household was given the opportunity to design its own garden according to the family's preference and taste. 5. The advantages of a rural area that city does not offer were fully utilized to provide the residents with convenience and pleasure of living.

• The Korean Journal of Ecology
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• v.21 no.3
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• pp.187-193
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• 1998

Seasonal changes of nitrogen fixation and growth characteristics of Melilotus suaveolens population under different light conditions were quantitatively analyzed during growting period. Height growth of M. suaveolens population was promoted after April and the shade (site 2) showed 10-20% increase of height growth in compared with that of sunny (site 1). Seasonal changes of biomass were in creased after March, the biomass at site 1 attained 78.5% that of site 2 in May. Chlorophyll content was maintained high value from March to April but, Chlorophyll content of leaf at site 1 was decreased 11.7% compared to that of site 2 in May. The nitrogen content of each organ of M. suaveolens showed higher value in March and then decreased, the high nitrogen contents of reproductive organ were achieved at the flowering stage at site 1. The root nodule of M. suaveolens population appeared in March and showed maximum value in early June and decreased remarkably after July, the amount of nodule formation of M. suaveolens at site 2 showed higher than that of site 1. The nitrogen fixation activity of root nodule of M. suaveolens initiated with shoot growth and showed maximum value in mid April, and attained second peak in early June and then decreased after July. The total nitrogen fixation of the plant showed higher value at site 2 than that of site 1. From the overall results, M. suaveolens showed increased growth under half-shady, well ventilated barren soil than fertile sunny site.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.235-242
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• 2012

Mikania micrantha, a neo-tropical vine, is spreading rapidly in the tropical part of Nepal and is now threatening the rural ecosystem including biodiversity and rural livelihoods. However, no attempt has been made to control the spread of M. micrantha. As a result, the vines are spreading freely and rapidly. After a thorough literature review and assessment of forest management practices, we proposed a manual cutting method, as it suits the Nepalese situation for several reasons: required labor is readily available, as local communities are managing forest patches, and the method does not have any potential adverse effects on non-target native species. Experimental plots were laid out in August 2011 to examine the effectiveness of manual cutting. Two different site types based on canopy coverage were selected and divided into three blocks based on cutting strategy. Four treatments were assigned across the experimental plots following a complete block design. We harvested above-ground biomass according to the assigned treatment. The results suggested that there should be at least two consecutive cuttings within a 3-week interval before flowering, and that three consecutive cuttings resulted in 91% mortality of the vines. In addition, cutting promoted regeneration of native plant species. Employing regular cutting operations can modify understory shade enhancing regeneration of native species, which is a desirable condition to constrain proliferation of M. micrantha. Periodic cuttings reduced the competitiveness of M. micrantha regardless of canopy openness, but native ground cover should be retained.

• Asian Journal of Turfgrass Science
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• v.13 no.3
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• pp.159-170
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• 1999

Preference of chestnut brown chafer (CBC), Adoretus tenuimaculatus was examined from chestnut leaves which were treated with different light condition, temperature and nitrogen fertilization. More CBC was attracted to leaves which grown at $30^{\circ}C$ than grown at $20^{\circ}C$,$ 25^{\circ}C$ and in the field. When attracted number of CBC was compared among full sunlight-grown, cloth shaded-grown and dark-grown plants, 4.0 in full sunlight grown and 5.0 in dark-grown plants. Amount of nitrogen fertilizer did not influence CBC feeding. The attractiveness of undamaged leaves with non-feeding beetles, leaves with feeding damaged, and leaves with artificial damaged was compared in replicated laboratory trials by placing the treatments in the petri-dish and counted the number of beetles that landed on the plants after 6 hr treatment. The highest number of beetles was attracted to chestnut leaf with feeding damaged ($7.7\pm$0.6) than undamaged leaf with non-feeding beetles ($5.3\pm$0.6) and artificial damaged ($4.3\pm$0.6). Managnese content in the leaves of chestnut grown in shade cloth-grown condition was higher than that in the leaves of chestnut that had been exposed to full sunlight condition and dark condition, and feeding damaged leaf.

• Journal of Ginseng Research
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• v.15 no.1
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• pp.36-40
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• 1991

A field experiment was conducted to examine the growth of one and two year old American ginseng (Panax guinguefolium L.) in the arid interior of British Columbia, Canada. For both years of plants, early season growth was characterized by rapid stem and leaf dry matter production. Root growth commenced in early June and continued until early September. One year old roots had a dry weight of 0.1 to 0.2g at the end of the growing season. The two years old roots commenced the growing season at 0.Is and increased in dry matter by a factor of ten-fold. Dry to fresh weight ratios for both years were similar for root, leaf and stem samples at the end of the growing season. Leaf area index for both years showed similarities in progression over the growing season. As a consequence of the effectiveness of the microclimate modification employed to permit American ginseng cultivation (elevated shade cloth and surface mulch), plant growth and development was extremely good. This indicates the potential for the cultivation of American ginseng in dryland environments.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.719-725
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• 2004

Mesquite or Vilayati babul (Prosopis juliflora) is a drought resistant, evergreen, spiny tree with drooping branches and a deep laterally spreading root system. It grows in semi-arid and arid tracts of tropical and sub-tropical regions of the world and is spreading because the leaves are unpalatable and animals do not digest its seed. The mesquite has become a major nuisance; cutting or pruning its branches to form a canopy would provide shade for travelers, aid harvesting of pods, as well as make available wood for fuel. An average plant starts fruiting by 3-4 years of age and yields annually 10-50 kg pods/ tree, which can be collected from May-June and September-October. Availability of pods worldwide is estimated to be about 2-4 million metric tonnes. Ripe pods are highly palatable; on dry matter basis they contain 12% crude protein, 15% free sugar, a moderate level of digestible crude protein (7% DCP) with a high level of energy (75% TDN). The pods contain low tannin levels below those toxic to animals. Seeds contain 31-37% protein; pods should be finely ground before feeding to facilitate utilization of the seeds. Mesquite pods could replace costlier feed ingredients such as grain and bran contributing 10-50% of the diet. Phosphorus supplements need to be added when mesquite pod, exceeds 20% of animals' diet.