• Title/Summary/Keyword: climatic factor

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Ecological Responses of Plants to Climate Change: Research Trends and Its Applicability in Korea (기후변화에 대한 식물의 생태적 반응: 연구동향과 한국에서의 적용가능성)

  • Kang, Hyesoon
    • Korean Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.319-331
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    • 2013
  • Recent climate change, which is mostly ascribed to anthropogenic activities, is believed to be a major factor leading to biodiversity decreases and ecosystem service deteriorations. I have reviewed recent studies on climate change effects for many ecological processes involved with plants, in order to improve our understanding of the nature of ecological complexity. Plants in general have better growth and productivity under high levels of $CO_2$, although the long term effects of such $CO_2$ fertilizers are still controversial. Over the last 30 years, the Earth has been greening, particularly at higher latitudes of the Northern Hemisphere, perhaps due to a relaxation of climatic constraints. Human appropriation of net primary productivity (NPP), which corresponds up to 1/3 of global NPP, is ultimately responsible for climate change and biodiversity decreases. Climate change causes phenological variations in plants, especially in regards to spring flowering and fall leaf coloring. Many plants migrate polewards and towards higher altitudes to seek more appropriate climates. On the other hand, tree mortality and population declines have recently been reported in many continents. Landscape disturbance not only hinders the plant migration, but also makes it difficult to predict the plants' potential habitats. Plant and animal population declines, as well as local extinctions, are largely due to the disruption of species interactions through temporal mismatching. Temperature and $CO_2$ increase rates in Korea are higher than global means. The degree of landscape disturbances is also relatively high. Furthermore, long-term data on individual species responses and species interactions are lacking or quite limited in Korea. This review emphasizes the complex nature of species responses to climate change at both global and local scales. In order to keep pace with the direction and speed of climate change, it is urgently necessary to observe and analyze the patterns of phenology, migration, and trophic interactions of plants and animals in Korea's landscape.

Development and Evaluation of Functional Lab Gowns in Point of Thermoregulation and Thermal Comfort (기능성 실험 가운의 개발 및 평가 -체온조절 및 온열 쾌적성을 중심으로-)

  • 최정화;이주영;김소영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.2
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    • pp.292-302
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    • 2004
  • The purpose of this study was to evaluate thermal properties of lab gowns developed from the point of safety and work efficiency. We evaluated thermal and subjective responses of subjects wearing functional new lab gowns (Type B, C, D) and a popular lab gown on the market (Type A). Type B was a new lab gown made of woven fabric with functional cuffs. Type C was a new apron made of woven fabric with arm protectors. Type D was a new lab gown made of non-woven material with functional cuffs and openings around the armpits. Temperature in the climatic chamber was set at 19$^{\circ}$C as an indoor temperature in winter and at 24$^{\circ}$C in summer. There were no significant differences in rectal temperature and heart rate among four types of gowns and between two air temperatures for 120 min. Mean skin temperature was much higher in the type A and B than in He type C and D (p .05). In the 19$^{\circ}$C air, clothing microclimate temperature on the back was the highest in the type B and was the lowest in the type C (p .05). Clothing microclimate humidity was not significant differences among gowns. In subjective .esponses, subjects perceived that Type B was the warmest gown in the 19$^{\circ}$C and the hottest and more humid in the 24$^{\circ}$C than other gowns. Inversely, type C was the coolest gown among four gowns. Both in the 19$^{\circ}$C and in the 24$^{\circ}$C, the Type D had gained most responses of being comfortable. In conclusion, the temperature difference of 5$^{\circ}$C was more of an influencing factor than the difference from four types of lab gowns. Secondly, we recommend the manufacturers to make lab gowns with functional cuffs for safety purposes. Thirdly, the spread of the type of apron with arm protector will contribute to increase of the frequency of wearing in summer. Fourthly, it is necessary to study continuously about lab gowns with non-woven materials for researchers exposed to toxic chemical and biological materials.

Insolation Modeling using Climate and Geo-Spatial Elements (기후요소와 지형 공간요소를 이용한 일사량 모델링)

  • Kim, Byung-Woo;Kang, In-Joon;Han, Ki-Bong
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.4
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    • pp.79-86
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    • 2010
  • This research is a thing about reverse operation about the solar power for location decision and increasing efficiency of the solar power generation equipments. The purpose of this research is reverse operation about the amount of sunshine using the climate and spatial elements. Following the result of correlation analysis, the wind-speed and cloud-amount factor are excluded, because the correlation and significance coefficients are out of value. Each outcome of regression analysis using the other four climate elements, and regression analysis using spatial elements is what the amount of sunshine and the solar altitude are the most influence to the insolation-modeling. Doing the regression analysis based on the precedent result make the result that climate elements have bigger coefficient of regression than spatial elements. This outcome means the climate elements are more influence than spatial elements.

Analysis of the Part Load Ratio Characteristics and Gas Energy Consumption of a Hot Water Boiler in a Residential Building under Korean Climatic Conditions (국내 기상조건하 주거용 건물 가스 보일러의 부분부하 특성과 에너지 사용량 분석)

  • Yu, Byeong Ho;Seo, Byeong-Mo;Moon, Jin-Woo;Lee, Kwang Ho
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.9
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    • pp.455-462
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    • 2015
  • Residential buildings account for a significant portion of the total building-energy usage in Korea, and a variety of research studies on the domestic boiler have therefore been carried out; however, most of these studies examined the boiler itself, whereby the part-load ratio characteristics and the corresponding gas-energy consumption patterns were not analyzed. In this study, the part-load ratio and operating characteristics of a domestic gas boiler were analyzed within a residential building equipped with a radiant floor-heating system; in addition, the energy consumption between condensing and conventional boilers was comparatively analyzed. Our results show that significant portions of the total operating hours, heating load, and energy consumption are in the part-load ratio range of 0 through 40%, whereby the energy consumption was significantly affected by the boiler efficiency under low part-load conditions. These results indicate that the part-load operation of a boiler is an important factor in residential buildings; furthermore, replacing a conventional boiler with a condensing boiler can reduce annual gas-energy usage by more than 20%.

Analysis of Heating Load Characteristics for Greenhouses Constructed in Reclaimed Lands (간척지 설치 온실의 난방부하 특성 분석)

  • Nam, Sang Woon;Shin, Hyun Ho
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.6
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    • pp.1-8
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    • 2017
  • The purpose of this study was to provide basic data for development of environmental design technology for greenhouses constructed in reclaimed lands. We analyzed the climatic conditions around seven major reclaimed land areas in Korea, which have a plan to install advanced horticultural complexes. The characteristics of heating load through the thermal environment measurement of the greenhouse in Saemangeum were analyzed. The part to be applied to the environmental design of the greenhouses in reclaimed lands were reviewed. The overall heat transfer coefficient of the experimental greenhouse with the aluminum screen and multi-layer thermal curtain averaged $3.79W/m^2^{\circ}C$. It represents a 44 % heat savings rate compared with plastic greenhouses with a single covering, which was significantly lower than that of the common greenhouses with 2-layer thermal curtains. This is because the experimental greenhouse was installed on reclaimed land and wind was stronger than the inland area. Among the total heating load, the transmission heat loss accounted for 96.4~99.9 %, and the infiltration loss and the ground heat exchange were low. Therefore, it is necessary to take countermeasures to minimize the transmission heat loss for greenhouses constructed in reclaimed lands. As the reclaimed land is located on the seaside, the wind is stronger than the inland area, and the fog is frequent. Especially, Saemangeum area has 2.6 times stronger wind speed and 3.4 times longer fog duration than the inland area. In designing the heating systems for greenhouses in reclaimed lands, it is considered that the maximum heating load should be calculated by applying the wind coefficient larger than the inland area. It is reasonable to estimate the operation cost of the heating system by applying the adjustment factor 10 % larger than the average in calculating the seasonal heating load.

Temperature Factor in Silvicultural View Point in Korea - Especially on Warmth- and Cold Index - (조림학적(造林學的)으로 본 온도인자(温度因子) - 온량지수(溫量指數)와 한량지수(寒量指數)를 중심(中心)으로 -)

  • Yim, Kyong-Bin;Lee, Soo-Wook
    • Journal of Korean Society of Forest Science
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    • v.25 no.1
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    • pp.1-12
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    • 1975
  • In this study, warmth and cold-indices were calculated from the climatic records for 30 year from 1931 to 1960 observed at the 80 weather stations as illustrated in Table 1 and Figs. 4 and 5. Iso-warmth index and iso-cold index lines were carefully tracked. However, subjectivity might be involved in this delimitation. The well recognized phenomena of phenology, the natural distribution of specified tree species and potentially cultivable zones of some species of economic importance were discussed with regard to these indices. It is seemed that the forest zones of Korea accepted commonly by foresters and researchers were more rationally matched with the cold indices rather than warmth indices. The forest improvement works by introduction, planting works and other related fields could be refered to these data.

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Spatio-temporal Dynamic Alteration of Forest Canopy Density based on Site Associated Factor: View from Tropical Forest of Nepal

  • Panta, Menaka;Kim, Kye-Hyun
    • Korean Journal of Remote Sensing
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    • v.22 no.5
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    • pp.313-323
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    • 2006
  • Forest Canopy Density is a dynamic process mediated by various natural and anthropogenic factors. It can be changed over time and locations in the same forest type and landscape. However, human dimensions are considered as the primary force of landscape change and subsequent forest canopy loss in tropical regions of the world. Many studies have been indicated that roads have a far greater impact on forests than simply allowing access for human use. Similarly, rivers have been used as means of transportation, hence illegal logging and felling further deplete forest canopy density. The main objective of this study was to investigate the spatio-temporal dynamic alterations of Forest Canopy Density (FCD) across with site associated factors such as biophysical, physical and human interferences in tropical region of Nepal from 1988 to 2001. Landsat TM and ETM+ of 1988 and 2001 were used to assess the spatial and temporal dynamic alterations of FCD. This analysis revealed that distance to human settlements at P=<0.01, rivers, human interferences (path and fire) and species composition had a statistically significance at P=<0.05 level. However, other factors did not show any significant relation. So, we concluded that understanding of dynamic alterations of FCD with respect to factors was quite complex phenomena. Other surrounding environment could also playa significant role. A comprehensive analysis could be required to understand such complexities. Therefore, additional factors such as climatic, biophysical, social, and institutional with respect to spatio-temporal variability should be considered for the better understanding of canopy dynamic.

Estimation of Future Land Cover Considering Shared Socioeconomic Pathways using Scenario Generators (Scenario Generator를 활용한 사회경제경로 시나리오 반영 미래 토지피복 추정)

  • Song, Cholho;Yoo, Somin;Kim, Moonil;Lim, Chul-Hee;Kim, Jiwon;Kim, Sea Jin;Kim, Gang Sun;Lee, Woo-Kyun
    • Journal of Climate Change Research
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    • v.9 no.3
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    • pp.223-234
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    • 2018
  • Estimation of future land cover based on climate change scenarios is an important factor in climate change impact assessment and adaptation policy. This study estimated future land cover considering Shared Socioeconomic Pathways (SSP) using Scenario Generators. Based on the storylines of SSP1-3, future population and estimated urban area were adopted for the transition matrix, which contains land cover change trends of each land cover class. In addition, limits of land cover change and proximity were applied as spatial data. According to the estimated land cover maps from SSP1-3 in 2030, 2050, and 2100, respectively, urban areas near a road were expanded, but agricultural areas and forests were gradually decreased. More drastic urban expansion was seen in SSP3 compared to SSP1 and SSP2. These trends are similar with previous research with regard to storyline, but the spatial results were different. Future land cover can be easily adjusted based on this approach, if econometric forecasts for each land cover class added. However, this requires determination of econometric forecasts for each land cover class.

Predicting the potential distribution of the subalpine broad-leaved tree species, Betula ermanii Cham. under climate change in South Korea

  • Shin, Sookyung;Dang, Ji-Hee;Kim, Jung-Hyun;Han, Jeong Eun
    • Journal of Species Research
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    • v.10 no.3
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    • pp.246-254
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    • 2021
  • Subalpine and alpine ecosystems are especially vulnerable to temperature increases. Betula ermanii Cham. (Betulaceae) is a dominant broad-leaved tree species in the subalpine zone and is designated as a 'Climate-sensitive Biological Indicator Species' in South Korea. This study aimed to predict the potential distribution of B. ermanii under current and future climate conditions in South Korea using the MaxEnt model. The species distribution models showed an excellent fit (AUC=0.99). Among the climatic variables, the most critical factors shaping B. ermanii distribution were identified as the maximum temperature of warmest month (Bio5; 64.8%) and annual mean temperature (Bio1; 20.3%). Current potential habitats were predicted in the Baekdudaegan mountain range and Mt. Hallasan, and the area of suitable habitat was 1531.52 km2, covering 1.57% of the Korean Peninsula. With global warming, future climate scenarios have predicted a decrease in the suitable habitats for B. ermanii. Under RCP8.5-2070s, in particular, habitat with high potential was predicted only in several small areas in Gangwon-do, and the total area suitable for the species decreased by up to 97.3% compared to the current range. We conclude that the dominant factor affecting the distribution of B. ermanii is temperature and that future temperature rises will increase the vulnerability of this species.

A Probability Modeling of the Crime Occurrence and Risk Probability Map Generation based on the Urban Spatial Information (도시공간정보 기반의 범죄발생 확률 모형 및 위험도 확률지도 생성)

  • Kim, Dong-Hyun;Park, Koo-Rack
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.10
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    • pp.207-215
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    • 2009
  • Recently, the research of the analysis of the crime spatial is increased by using the computer information technology and GIS (Geometric Information System) in order to prevent the urban crime so as to increase the urbanization rate. In this paper, a probability map formed by the raster is organized by the quantification of crime risk per the cell using the region property of the urban spatial information in the static environment. Also, a map of the risk probability is constructed based on the relative risk by the region property, the relative risk by the facility, the relative risk by the woody plant and the river, and so on. And, this integrated risk probability map is calculated by averaging the individual cell risk applied to the climatic influence and the seasonal factor. And, a probability map of the overall risk is generated by the interpretation key of the crime occurrence relative risk index, and so, this information is applied to the probability map quantifying the occurrence crime pattern. And so, in this paper, a methodology of the modeling and the simulation that this crime risk probability map is modified according to the passage of time are proposed.