• Journal of Ecology and Environment
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• v.45 no.4
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• pp.163-169
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• 2021

Background: Understanding the habitat characteristics of the endangered Siberian flying squirrel Pteromys volans is the first step in conserving and managing the forests it requires for nesting, gliding, and feeding. Therefore, in the present study, we characterized the habitats of P. volans using GIS analysis of 411 forest sites in South Korea where fecal droppings were found. Results: Fecal signs of P. volans were found in various regions in South Korea, including the Baekdudaegan Mountains. GIS analysis with six environmental layers (vegetation type, wood-age class, diameter at breast height [DBH], crown density, elevation, and distance from stream) revealed that fecal signs of P. volans were more frequently found in broad-leaved deciduous forests (42%) located 200-399 m above sea level (43.1%) and 0-199 m from the nearest stream (53%), with 5th class wood-age (35.3%), middle size class DBH (51.1%), and high crown density (71%). Conclusions: The present study provides information on the biotic and abiotic characteristics of P. volans habitats. In South Korea, the fecal droppings of P. volans were found predominantly old deciduous broadleaf forests. Further studies are needed to reveal whether the more frequent occurrence of P. volans dropping in broadleaf forests may be due to a particular preference of this species for the forests or to a simple reflection of the area of the broadleaf forests occupying a much larger area than other forest types in Korea.

• Journal of Ecology and Environment
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• v.46 no.2
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• pp.111-125
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• 2022

Background: Zanthoxylum armatum is one of the 30 prioritized medicinal plants for economic development of Nepal with a high trade value. Understanding the ecology of individual species is important for conservation and cultivation purposes. However, relation of ecological factors on the distribution and populations of Z. armatum in Nepal remain unknown. To address this knowledge gap, an attempt has been made to study the population structure, distribution, and regeneration potentiality of Z. armatum. Vegetation sampling was conducted at six different localities of Salyan district along the elevation range of 1,000 m to 2,000 m. Results: Altogether 50 plant species belonging to 44 genera under 34 families were found to be associated with Z. armatum. Significantly higher species richness was found at Rim (1,400-1,700 m) and Chhatreshwori (1,800-2,000 m) and lower at Kupinde (1,600-1,800 m). The highest population density of Z. armatum was at Kupinde (1,600-1,800 m) with a total of 1,100 individuals/ha. and the lowest at Chhatreshwori (1,800-2,000 m) with 740 individuals/ha. Based on the A/F value (Whitford index), it can be said that Z. armatum has random distribution in the study area. The plants were categorized into seedlings, saplings and adults based on plant height and the status of natural regeneration category determined. The regeneration potentiality of Z. armatum in the study area was fair with the average seedlings and saplings densities of 150 and 100 individuals/ha. Respectively. A Shannon-Weinner index mean value of 2.8 was obtained suggesting high species diversity in the study area. Conclusions: The natural distribution and regeneration of Z. armatum is being affected in the recent years due to anthropogenic disturbances. Increasing market demand and unsustainable harvesting procedures are posing serious threat to Z. armatum. Thus, effective conservation and management initiatives are most important for conserving the natural population of Z. armatum in the study area.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.149-159
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• 2010

This paper analyzes data on the composition, status, diversity, and distribution pattern of invasive forest undergrowth in a protected area (Khadimnagar National Park) of Northeastern Bangladesh. Assessment was done by means of stratified random sampling to diversify the invasive forest undergrowth species. For vegetation survey, 45 plots were taken randomly in ($2m{\times}2m$) circular plot from three topographical regions namely top of the hill, middle slope and plain land (15 plots from each region) and a total of 715 individuals, 22 invasive species belonging to 17 families were recorded from the study site. Among invasive species, shrubs constitute 10 species, herbs 9 species, and vines 3 species respectively. Mass number of invasive undergrowth species was grows in plain land (45.45%) followed by middle slope (31.82%). Based on the survey, invasive undergrowth plants of study areas were also categorized into three degrees of invasiveness e.g., highly invasive, moderately invasive and potentially invasive. Herbs, shrubs, and vines constitute the highest density at Chromolaema odorata (Linn.) King. (1.09), relative density at Chromolaema odorata (Linn.) King. 6.85%; highest and lowest frequency was calculated at Cassia alata L. (64.44%) and Diplazium esculentum (24.44%); for relative frequency the highest was Cassia alata L., which occupies 6.64%. Determination of the abundance of the different species revealed that Cassia alata L., constitutes (3.36) followed by Pteris cretica Wilsonii (3.14) of the area. The presence of invasive undergrowth species always reduced the number of associated species. Therefore, an extensive in-depth long-term investigation, proper policy formulation and management interventions and further study and continuous monitoring on their impacts need to be triggered targeting the control of the invasive undergrowth species of this protected area. In this aspect, national and international organization could help to conserve its biodiversity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.1-28
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• 2019

This study analyzed the density and mortality rate of Korean fir at 9 sites where individuals of Korean firs were marked into the live and dead trees with coordinates on orthorectified aerial images by digital photogrammetric system. As a result of the analysis, Korean fir in each site showed considerable heterogeneity in density and mortality rate depending on the location within site. This make it possible to assume that death of Korean fir can occur by specific factors that vary depending on the location. Based on the analyzed densities and mortality rates of Korea fir, we investigated the correlation between topographic factors such as altitude, terrain slope, drainage network, solar radiation, aspect and the death of Korean fir. The density of Korean fir increases with altitude, and the mortality rate also increases. A negative correlation is found between the terrain slope and the mortality rate, and the mortality rate is higher in the gentle slope where the drainage network is less developed. In addition, it is recognized that depending on the aspect, the mortality rate varies greatly, and the mean solar radiation is higher in live Korean fir-dominant area than in dead Korean fir-dominant area. Overall, the mortality rate of Korean fir in Mt. Halla area is relatively higher in areas with relatively low terrain slope and low solar radiation. Considering the results of previous studies that the terrain slope has a strong negative correlation with soil moisture and the relationship between solar radiation and evaporation, these results lead us to infer that excess soil moisture is the cause of Korean fir mortality. These inferences are supported by a series of climate change phenomena such as precipitation increase, evaporation decrease, and reduced sunshine duration in the Korean peninsula including Jeju Island, increase in mortality rate along with increased precipitation according to the elevation of Mt. Halla and the vegetation change in the mountain. It is expected that the spatial patterns in the density and mortality rate of Korean fir, which are controlled by topography such as altitude, slope, aspect, solar radiation, drainage network, can be used as spatial variables in future numerical modeling studies on the death or decline of Korean fir. In addition, the method of forest distribution survey using the orthorectified aerial images can be widely used as a numerical monitoring technique in long - term vegetation change research.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.83-91
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• 2003

This study was conducted to clarify the characteristics of bird communities due to different habitat types on 3 sites in Han river area from May 2001 to January 2002. Water area was the most dominant habitat type in each site and also forest was dominant habitat type in site 1(Paldang area). Site 2(Bam island area) had various habitat types e.g. shrub field sandv plain, reed bed and grass field. Total 52 bird species were recorded on 3 sites in Han river. Ducks were the most dominant species, especially in January 2002. Density of individuals were higher in site 1 and 2, but lower in site 3(Nanjido area). In January 2002, dabbling ducks were dominant in site 2, and diving ducks were in site 1. Among diving ducks, common merganser Mergus merganser showed high density in site 2 and pochard Aythya ferina did in site 1. In site 1, coot Fulica atra showed also high density Diverse habitat types could be support foraging resources for dabbling ducks in site 2. High density of pochard and coot would be related to abundant aquatic plants and stable water depth in site 1. Manipulation of riparian zone in site 3 into natural vegetation would increase the bird species diversity. By the manipulation of habitat, habitat potentiality of birds would be increase in Han river area.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.94-99
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• 2011

This study was performed to investigate the effect of foliar feeding as the fertilization on creeping benrgrass green. Research results have showed that the visual quality of bentgrass as well as shoot density and chlorophyll index dramatically improved after foliar feeding. Shoot density of bent grass in foliar based fertilization was 2.8 ea/$cm^2$ higher than that of the liquid based fertilization during the experiment period, moreover that the foliar feeding is more effective to alleviate shoot density during the rainy season in summer. Results showed that foliar feeding was key role to achieve the stable visual quality, chlorophyll index and maintained Normalized Difference Vegetation Index (NDVI) throughout the year in addition to get fast recovery after aeration and dry spot. These were consistent with the previous research of foliar feeding which directly provided nutrient to the turfgrass leaf thus increased turfgrass growth within a short time. It is projected to be a especially adequate management program during the hot summer season in which the nutrition feeding is low. However, root growth was no significant difference between foliar based fertilization and liquid based fertilization. Golf Course managers also should consider about the number of frequent fertilizing. Lastly, it was no big change in chemical property by soil foliar based fertilization which is meaning of preventing the soil salinization, meanwhile, it is prone to reach the nutrient deficiency. It hopes to be settled as the general fertilization in golf course of Korea, since there are many advantages of foliar based fertilization program. It is suggested to study more practical process of foliar feeding through the further research.

• Korean Journal of Weed Science
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• v.18 no.4
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• pp.356-363
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• 1998

In general weed vegetation analysis has been applied to the study of weed population shift. However, it is a limited tool for understanding a problem region and a specific weed species in a certain area. Recently GIS may be used as an important tool to solve this target or to conduct specific field analysis which enables to introduce a reasonable management strategy. Thus, the GIS study was carried out to understand an integrated weed population changes between 1981 and 1992 in Korea. The nationwide weed survey was performed through the whole rice paddy fields in 1981 and 1992. Weed occurrence was totally different over whole country based on these data. In 1981 a region with high weed occurrence was at western and central areas of Korea in terms of weed population density but this was changed into western and southern area in 1992. In both years there were high weed population density at Taean, Seosan county of Chungnam province in Korea. Thus, this particular area may be needed to introduce a special strategy to reduce weed population density and/or to control problem weed species.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.74-82
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• 2003

This study was carried out to understand how the bird community would change in a stream ecosystem after implementation of close-to-nature river improvement techniques conducted on the Gwacheon, Seocho and Hakyeul reaches in the Yangiae Stream, 'Seoul. At the Gwacheon reach, the number of species and individuals tended to decline. However, at the Seocho reach, the number of species was increased while the number of individuals appeared to be not changed greatly. Especially, density of Dabbling Ducks were rapidly increased. At the Hakyeul reach was both the number of species and the number of individuals were increased. Density of Herons and Dabbling Ducks rose, while density of Wagtails was decreased suddenly. Except the Gwacheon reach, the survey areas were gradually improved in species richness and density after the construction of river improvement. We suggested that the naturally-formed meandering (channel) bar, restoration of riparian vegetation and artificial ponds were helpful for birds habitation, however bicycle path constructed in flood plain was negative.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.140-147
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• 2012

This study was conducted to investigate optimum planting density for apartment complex. The validity of Landscape Architecture Criteria of Korea was checked for it. We compared our field data with Landscape Architecture Criteria. In this step, the tree density of urban forest was regarded as standard. Field study was examined in 3 apartment complexes located in capital area, especially completed during these 10 years. 10 sites in each complex were selected and tree density per unit area were calculated. This field study data was divided standard size and large size which received weight. And, it was compared and analyzed. And crown projected area(CPA) was calculated considering proper growth of low vegetation and sufficient shade. The outcome shows that minimum size of Landscape Architecture Criteria is rational. But, in the case of planting large size tree received weight, tree density was short comparing with the tree density of urban forest and CPA was less than 50%. By the result of field study in 3 apartment complex, the tree density of apartment complex satisfied or exceeded Landscape Architecture Criteria. But, in the case of planting large size tree, tree density and CPA show high density due to addition planting for deficient landscape. Therefore, the revision of the Landscape Architecture Criteria was required such as deletion or minimization of the weighted clause about the large size tree and regulate the limit CPA not less than 50% and not more than 100%.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1087-1091
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• 2006

This paper describes the current spatial patterns of the net primary productivity (NPP) of the terrestrial vegetation and carbon emission (C) in the world due to the burning of fossil fuels in order to clarify the amount of expansion of human activity. The C/NPP value varies spatially from almost zero to several tens of thousand times the local NPP. C/NPP is higher under the condition of extensive human activities due to a high human population density or when the local NPP is extremely low in severe climatic zones. In contrast, the low C/NPP areas are distributed mainly in sparsely populated districts, loading to a low impact of human activity. Although the area where C/NPP is less than 10% accounts for about 70% of the entire land area, one-third of these areas cannot contribute to carbon absorption because of low NPP with a shortage of climatic resources. Since more than half of the areas of the remaining areas are agricultural land and forest ecosystems with high NPP, the possible afforestation area was evaluated to be maximum of $30{\times}10^{6}\;km^{2}$; here only sequestrate carbons that correspond to 2% of the global total NPP are present. These analyses revealed that presently most of the areas where the NPP is high are those exclusively used by humans and that it is difficult for large-scale forest plantations to absorb a substantial amount of the carbon emitted annually by humans.