• Title/Summary/Keyword: climatic variables

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Local Climate Mediates Spatial and Temporal Variation in Carabid Beetle Communities on Hyangnobong, Korea

  • Park, Yong Hwan;Jang, Tae Woong;Jeong, Jong Cheol;Chae, Hee Mun;Kim, Jong Kuk
    • Journal of Forest and Environmental Science
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    • v.33 no.3
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    • pp.161-171
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    • 2017
  • Global environmental changes have the capacity to make dramatic alterations to floral and faunal composition, and elucidation of the mechanism is important for predicting its outcomes. Studies on global climate change have traditionally focused on statistical summaries within relatively wide scales of spatial and temporal changes, and less attention has been paid to variability in microclimates across spatial and temporal scales. Microclimate is a suite of climatic conditions measured in local areas near the earth's surface. Environmental variables in microclimatic scale can be critical for the ecology of organisms inhabiting there. Here we examine the effect of spatial and temporal changes in microclimates on those of carabid beetle communities in Hyangnobong, Korea. We found that climatic variables and the patterns of annual changes in carabid beetle communities differed among sites even within the single mountain system. Our results indicate the importance of temporal survey of communities at local scales, which is expected to reveal an additional fraction of variation in communities and underlying processes that has been overlooked in studies of global community patterns and changes.

A New Sampling Method of Marine Climatic Data for Infrared Signature Analysis (적외선 신호 해석을 위한 해양 기상 표본 추출법)

  • Kim, Yoonsik;Vaitekunas, David A.
    • Journal of the Society of Naval Architects of Korea
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    • v.51 no.3
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    • pp.193-202
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    • 2014
  • This paper presents a new method of sampling the climatic data for infrared signature analysis. Historical hourly data from a stationary marine buoy of KMA(Korean Meteorological Administration) are used to select a small number of sample points (N=100) to adequately cover the range of statistics(PDF, CDF) displayed by the original data set (S=56,670). The method uses a coarse bin to subdivide the variable space ($3^5$=243 bins) to make sample points cover the original data range, and a single-point ranking system to select individual points so that uniform coverage (1/N = 0.01) is obtained for each variable. The principal component analysis is used to calculate a joint probability of the coupled climatic variables. The selected sample data show good agreement to the original data set in statistical distribution and they will be used for statistical analysis of infrared signature and susceptibility of naval ships.

Correlation Analysis between Climatic Factors and Radial Growth and Growth Prediction for Pinus densiflora and Larix kaempferi in South Korea (소나무와 일본잎갈나무의 연륜생장과 기후 요소와의 상관관계 분석 및 생장예측)

  • Chung, Junmo;Kim, Hyunseop;Kim, Meesook;Chun, Yongwoo
    • Journal of Korean Society of Forest Science
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    • v.106 no.1
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    • pp.77-86
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    • 2017
  • This study was conducted to analyze the relationship among climatic factors and radial growth of Pinus densiflora and Larix kaempferi in South Korea. To determine the climate-growth relationship, cluster analysis was applied to group surveyed regions by the climatical similarity, and a dendroclimatological model was developed to predict radial growth for each climate group under the RCP 4.5 and RCP 8.5 scenarios for greenhouse gases. The cluster analysis showed four climatic clusters (Cluster 1~4) from 10 regions for P. densiflora and L. kaempferi. The dendroclimatological model was developed through climatic variables and standardized residual chronology for each climatic cluster of P. densiflora and L. kaempferi. Four climatic variables were used in the models for P. densiflora ($R^2$ values between 0.38 to 0.58). Two to five climatic variables were used in the models for L. kaempferi ($R^2$ values between 0.31 to 0.43). The growth simulations with two RCP climate-change scenarios(RCP 4.5 and RCP 8.5) were used for growth prediction. The radial growth of the Cluster 4 of P. densiflora, the mountainous region at high elevation, tend to increase, while those of cluster 2 and 3 of P. densiflora, the region of the hightest average temperature, tends to decrease. The radial growth of the Cluster 1 of L. kaempferi the region of the lowest minimum temperature, while that of Cluster 2, the region of the highest average temperature, tends to decrease. The radial growth of Cluster 3 of L. kaempferi, the region in the east coast and Cluster 4, the region at high elevation, tends to hold steady. The results of this study are expected to provide valuable information necessary for predicting changes in radial growth of Pinus densiflora and Larix kaempferi caused by climate change.

Classification of Agro-Climatic Zones of the State of Mato Grosso in Brazil (브라질 마토그로소 지역의 농업기후지대 구분)

  • Jung, Myung-Pyo;Park, Hye-Jin;Hur, Jina;Shim, Kyo-Moon;Kim, Yongseok;Kang, Kee-Kyung;Ahn, Joong-Bae
    • Korean Journal of Environmental Agriculture
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    • v.38 no.1
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    • pp.34-37
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    • 2019
  • BACKGROUND: A region can be divided into agroclimatic zones based on homogeneity in weather variables that have greatest influence on crop growth and yield. The agro-climatic zone has been used to identify yield variability and limiting factors for crop growth. This study was conducted to classify agro-climatic zones in the state of Mato Grosso in Brazil for predicting crop productivity and assessing crop suitability etc. METHODS AND RESULTS: For agro-climatic zonation, monthly mean temperature, precipitation, and solar radiation data from Global Modeling and Assimilation Office (GMAO) of National Aeronautics and Space Administration (NASA, USA) between 1980 and 2010 were collected. Altitude and vegetation fraction of Brazil from Weather Research and Forecasting (WRF) were also used to classify them. The criteria of agro-climatic classification were temperature in the hottest month ($30^{\circ}C$), annual precipitation (600 mm and 1000 mm), and altitude (200 m and 500 m). The state of Mato Gross in Brazil was divided into 9 agro-climatic zones according to these criteria by using matrix classification method. CONCLUSION: The results could be useful as information for estimating agro-meteorological characteristics and predicting crop development and crop yield in the state of Mato Grosso in Brazil.

Effect of rearing season, host plants and their interaction on economical traits of tropical tasar silkworm, Antheraea mylitta Drury- an overview

  • Bhatia, Narendra Kumar;Yousuf, Mohammad
    • International Journal of Industrial Entomology and Biomaterials
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    • v.29 no.1
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    • pp.93-119
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    • 2014
  • Tropical tasar silkworm, Antheraea mylitta (Lepidoptera: Saturniidae) is a polyphagous silk producing forest silkworm of commercial importance in India. Forest dependent people rear its larvae on different forestry host plants twice or thrice in a year for small household income. Larvae of A. mylitta feeds on many forest tree species, but always show a great degree of selectivity as a function of its behavioural responses to physical structure and chemical features of the host plants. Cocoon crop of A. mylitta is influenced by heterogeneity of tasar food plants and climatic conditions of the habitat. The role of host plants, temperature, humidity, rainfall, photoperiod and climatic variables on the growth and development of insects have clearly been demonstrated. This article entails an in-depth analysis on ecological and nutritional aspects of A. mylitta, which may provide selective information to researcher and forest managers, who are particularly associated with livelihood improvement of the poor people in forested area through location specific forest insect industry.

Modeling the potential climate change-induced impacts on future genus Rhipicephalus (Acari: Ixodidae) tick distribution in semi-arid areas of Raya Azebo district, Northern Ethiopia

  • Hadgu, Meseret;Menghistu, Habtamu Taddele;Girma, Atkilt;Abrha, Haftu;Hagos, Haftom
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.427-437
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    • 2019
  • Background: Climate change is believed to be continuously affecting ticks by influencing their habitat suitability. However, we attempted to model the climate change-induced impacts on future genus Rhipicephalus distribution considering the major environmental factors that would influence the tick. Therefore, 50 tick occuance points were taken to model the potential distribution using maximum entropy (MaxEnt) software and 19 climatic variables, taking into account the ability for future climatic change under representative concentration pathways (RCPs) 4.5 and 8.5, were used. Results: MaxEnt model performance was tested and found with the AUC value of 0.99 which indicates excellent goodness-of-fit and predictive accuracy. Current models predict increased temperatures, both in the mid and end terms together with possible changes of other climatic factors like precipitation which may lead to higher tick-borne disease risks associated with expansion of the range of the targeted tick distribution. Distribution maps were constructed for the current, 2050, and 2070 for the two greenhouse gas scenarios and the most dramatic scenario; RCP 8.5 produced the highest increase probable distribution range. Conclusions: The future potential distribution of the genus Rhipicephalus show potential expansion to the new areas due to the future climatic suitability increase. These results indicate that the genus population of the targeted tick could emerge in areas in which they are currently lacking; increased incidence of tick-borne diseases poses further risk which can affect cattle production and productivity, thereby affecting the livelihood of smallholding farmers. Therefore, it is recommended to implement climate change adaptation practices to minimize the impacts.

Comparison of reference evapotranspiration estimation methods with limited data in South Korea

  • Jeon, Min-Gi;Nam, Won-Ho;Hong, Eun-Mi;Hwang, Seonah;Ok, Junghun;Cho, Heerae;Han, Kyung-Hwa;Jung, Kang-Ho;Zhang, Yong-Seon;Hong, Suk-Young
    • Korean Journal of Agricultural Science
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    • v.46 no.1
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    • pp.137-149
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    • 2019
  • Accurate estimation of reference evapotranspiration (RET) is important to quantify crop evapotranspiration for sustainable water resource management in hydrological, agricultural, and environmental fields. It is estimated by different methods from direct measurements with lysimeters, or by many empirical equations suggested by numerous modeling using local climatic variables. The potential to use some such equations depends on the availability of the necessary meteorological parameters for calculating the RET in specific climatic conditions. The objective of this study was to determine the proper RET equations using limited climatic data and to analyze the temporal and spatial trends of the RET in South Korea. We evaluated the FAO-56 Penman-Monteith equation (FAO-56 PM) by comparing several simple RET equations and observed small fan evaporation. In this study, the modified Penman equation, Hargreaves equation, and FAO Penman-Monteith equation with missing solar radiation (PM-Rs) data were tested to estimate the RET. Nine weather stations were considered with limited climatic data across South Korea from 1973 - 2017, and the RET equations were calculated for each weather station as well as the analysis of the mean error (ME), mean absolute error (MAE), and root mean square error (RMSE). The FAO-56 PM recommended by the Food Agriculture Organization (FAO) showed good performance even though missing solar radiation, relative humidity, and wind speed data and could still be adapted to the limited data conditions. As a result, the RET was increased, and the evapotranspiration rate was increased more in coastal areas than inland.

Development of Evaluation Model of Pumping and Drainage Station Using Performance Degradation Factors (농업기반시설물 양·배수장의 성능저하 요인분석 및 성능평가 모델 개발)

  • Lee, Jonghyuk;Lee, Sangik;Jeong, Youngjoon;Lee, Jemyung;Yoon, Seongsoo;Park, Jinseon;Lee, Byeongjoon;Lee, Joongu;Choi, Won
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.4
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    • pp.75-86
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    • 2019
  • Recently, natural disasters due to abnormal climates are frequently outbreaking, and there is rapid increase of damage to aged agricultural infrastructure. As agricultural infrastructure facilities are in contact with water throughout the year and the number of them is significant, it is important to build a maintenance management system. Especially, the current maintenance management system of pumping and drainage stations among the agricultural facilities has the limit of lack of objectivity and management personnel. The purpose of this study is to develop a performance evaluation model using the factors related to performance degradation of pumping and drainage facilities and to predict the performance of the facilities in response to climate change. In this study, we focused on the pumping and drainage stations belonging to each climatic zone separated by the Korea geographical climatic classification system. The performance evaluation model was developed using three different statistical models of POLS, RE, and LASSO. As the result of analysis of statistical models, LASSO was selected for the performance evaluation model as it solved the multicollinearity problem between variables, and showed the smallest MSE. To predict the performance degradation due to climate change, the climate change response variables were classified into three categories: climate exposure, sensitivity, and adaptive capacity. The performance degradation prediction was performed at each facility using the developed performance evaluation model and the climate change response variables.

Regional Diversity Pattern of Spring Moths and Climatic Effects on Moth Catches (봄 출현 나방의 지역별 종 다양성 양상과 출현에 미치는 기후영향 연구)

  • Noh, Dong-Ho;Kim, Sung-Soo;Choi, Sei-Woong
    • Korean Journal of Environmental Biology
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    • v.34 no.1
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    • pp.30-36
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    • 2016
  • We investigated the diversity pattern of spring moths across two regions of South Korea, Yongin city (middle part) and Muan gun (southern part) and the effects of climatic variables on moth species richness and abundance. Moths were weekly collected using UV light trap in April from 2013 to 2015. Climatic factors included growth degree day with base temperature 8 (GDD8), average temperature, precipitation, duration of sunshine, wind speed, and snow cover. The climatic effects on moth species richness and abundance were analyzed by short (0~3 weeks before collecting) and long (4~12 weeks before collecting) time periods, respectively. The diversity of spring moths showed the similar pattern of species composition at family level. However the dominant family differed depending on the region: Geometridae at middle part and Noctuidae at southern part. In addition the dominant species of Noctuidae occurred early in April and that of Geometridae moths occurred later in April. Three short-term climatic factors, GDD8, duration of sunshine, and precipitation one week before collecting were significant on moth species richness and abundance, while only one long-term climatic factor, temperature four weeks before collecting was significantly affected on moth species richness. We found that both Geometridae and Noctuidae were dominant in spring moth fauna across South Korea and they were different in the dominance and flying time in April. The occurrences of spring moths were largely affected by warmness and precipitation. The current global warming could affect the occurrence of spring moths and this should be monitored consistently.

Reference evapotranspiration estimates based on meteorological variables over Korean agro-climatic zones for rice field (남한지역의 논 농업기후지대에 대한 기상자료 기반의 기준 증발산량 추정)

  • Jung, Myung-Pyo;Hur, Jina;Shim, Kyo-Moon;Kim, Yongseok;Kang, Kee-Kyung;Choi, Soon-Kun;Lee, Byeong-Tae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.4
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    • pp.229-237
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    • 2019
  • This study was conducted to estimate annual reference evapotranspiration (ET0) for the agro-climatic zones for rice paddy fields in South Korea between 1980 and 2015. The daily ET0 was estimated by applying the Penman-Monteith method to meteorological data from 61 weather stations provided by Korean Meteorological Administration (KMA). The average of annual ET0 from 1980 to 2015 was 1334.1±33.89 mm. The ET0 was the highest at the Southern Coastal Zone due to their higher air temperature and lower relative humidity. The ET0 had significantly increased with 2.81 mm/yr for the whole zones over 36 years. However, the change rate of it was different among agro-climatic zones. The annual ET0 highly increased in central zones and eastern coastal zones. In terms of correlation coefficient, the temporal change of the annual ET0 was closely related to variations of four meteorological factors (i.e., mean, minimum temperatures, sunshine duration, and relative humidity). The results demonstrated that whole Korean agro-climatic zones have been undergoing a significant change in the annual ET0 for the last 36 years. Understanding the spatial pattern and the long-term variation of the annual ET0 associated with global warming would be useful to improve crop and water resource managements at each agro-climatic zone of South Korea.