• 한국산림과학회지
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• 제105권1호
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• pp.122-131
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• 2016

본 연구는 연륜기후학적 방법에 의해 기후인자가 우리나라에 분포하는 일본잎갈나무의 연륜생장에 미치는 영향을 구명하기 위해 수행하였다. 본 연구에서는 먼저 일본잎갈나무의 연도별 생장특성을 분석하기 위해 제5차 국가산림자원자료에서 수집된 일본잎갈나무의 연륜생장 자료를 정리하였다. 한편 일본잎갈나무의 연륜생장과 기후변수와의 관계를 구명하기 위해 1950년부터 2010년까지 정리된 월평균 기온과 월강수량 자료를 시군 단위로 정리하였다. 기후조건의 유사성에 근거하여 일본잎갈나무의 시군별 연륜생장 자료를 군집분석한 결과 6 개의 기후 군집으로 구분할 수 있었다. 이와 함께 연륜생장 자료에 대한 크로스데이팅과 표준화 절차를 통해 각 군집별 지표연대기를 제작하였다. 각 군집별 지표연대기의 적합성은 연륜생장의 평균민감도, 자기상관계수, 신호 대 잡음비, 신호강도와 같은 기초통계량 분석을 통해 점검하였다. 최종적으로 각 군집별 일본잎갈나무의 연륜생장과 기후변수 간의 관계를 구명하기 위해 반응함수 분석을 실시하였다. 본 연구에서 얻어진 결과는 일본잎갈나무의 지역별 생장특성의 추정뿐만 아니라 기후변화에 따른 생장패턴의 변화 예측에 필요한 유용한 정보로 활용될 수 있을 것으로 기대된다.

• 한국산림과학회지
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• 제99권6호
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• pp.908-913
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• 2010

본 연구는 한국 중부지방의 소나무와 참나무류의 생장에 기후와 지형인자가 미치는 영향을 분석하였다. 입목의 반경생장량과 기상 인자간의 관계를 규명하기 위해 수목의 목편을 채취하고 연년반경생장량을 측정하였다. 본 연구에서는 연년반경생장량이 기본적으로 수령에 영향을 받는다고 가정하여 수령을 독립변수로 하는 생장량을 추정하고 이를 기반으로 수령 30년 일때의 생장량을 표준생장량으로 정의하여 추정하였다. 표준생장량의 공간분석을 통해 소나무 생장의 공간적인 변이성을 발견하였으며, Generalized Additive Model(GAM) 통해 지형 및 기상인자와 표준 생장량간의 관계를 밝힐 수 있었다. 기온상승은 소나무 생장에는 부(-)의 영향을 참나무에는 양(+)의 영향을 주며, 강수량 증가는 두 수종 모두에게 부(-)의 영향을 주는 것으로 나타났다. 또한, 표준생장량과 지형 및 기상 인자간의 관계식을 GIS기반 임상도의 소나무와 참나무류 공간분포에 적용하여 기온상승에 대한 소나무와 참나무류의 공간분포변화를 예측하였다. 이를 통해 우리나라의 소나무는 참나무류에 비해 기후변화에 취약하며, 60년 이후에는 동해안 및 남부지역을 중심으로 대부분의 소나무림이 참나무류림으로 대체될 것으로 예측되었다.

• 대한토목학회논문집
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• 제12권2호
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• pp.77-85
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• 1992

아스팔트 콘크리트 포장체는 기후변화에 따라 각 층의 물성이 변화하는 특성을 갖고 있다. 따라서 아스팔트 콘크리트 포장체의 설계 및 해석에 있어서는 물성변화 특성을 고려한 대표적 기후조건에서 포장재료의 물성치를 적용하여, 포장체의 설계 또는 구조해석을 실시하여야 할 것이다. 본 연구에서는 아스팔트 콘크리트 포장체의 설계 및 해석과 관련하여 우리나라에 적합한 대표적 기후조건인 설계온도를 추정하기 위하여, damage effect 분석에 의한 설계온도 추정 알고리즘을 제안하고 이를 전산화하였다. 분석대상 지역은 서울, 대전, 부산 3지역으로 하고 각 지역의 기후특성자료와 정부, 호남, 남해고속도로의 6개 포장단면에 본 연구 제안의 알고리즘 해석과정을 적용하여 국내조건의 설계온도를 추정하였으며, 추정한 설계온도 조건에 적합한 아스팔트 콘크리트 포장체의 파괴기준식을 제안하였다. 연구결과 우리나라의 설계온도는 $17^{\circ}C$가 적합함이 밝혀졌다. 설계온도 $17^{\circ}C$는 아스팔트 콘크리트 표층온도 $23.6^{\circ}C$에 해당되기 때문에 현재 국내에서 사용되는 재료 온도 $20^{\circ}C$에서의 아스팔트 콘크리트 표층 재료의 물성치(AASHTO의 경우)는 과대 평가되고 있음을 알 수 있었다. 또한, 본 연구에서의 설계온도 추정치, $17^{\circ}C$는 SHELL Design Chart에 의한 결과와 유사함을 알 수 있었다.

• 수산경영론집
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• 제46권2호
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• pp.31-41
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• 2015

This study aimed to analyze the relationship between sea surface temperature as a climatic element and catch amount of offshore and coastal fisheries in Korea using annual time series data from 1970 to 2013. It also tried to predict the future changes in catch amount of fisheries by climate change. Time series data on variables were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation between variables was found from a cointegration test. The result of Granger causality test indicated that the sea surface temperature would cause directly changes in catch amount of offshore and coastal fisheries. The result of regression analysis on sea surface temperature and catch amount showed that the sea surface temperature would have negative impacts on the catch amount of offshore and coastal fisheries. Therefore, if the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch amount of offshore and coastal fisheries was predicted to decrease.

• Environmental Engineering Research
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• 제22권4호
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• pp.347-355
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• 2017

This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.481-501
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• 2007

Excessive rainfalls due to climatic changes can trigger an increase in rainfall-induced slope failures that pose real threats to both lives and properties. Many high slopes in residual soils could stand at a steep angle, but failed during or after rainfall. Commonly, these slopes have a deep groundwater table and negative pore-water pressures in the unsaturated zone above the groundwater table contribute to the shear strength of soil and consequently to factor of safety of the slope. Stability assessment of slope under rainfall requires information on rate of rainwater infiltration in the unsaturated zone and the resulting changes in pore-water pressure and shear strength of soil. This paper describes the application of unsaturated soil mechanics principles and theories in the assessment of rainfall effect on stability of slope through proper characterization of soil properties, measurement of negative pore-water pressures, seepage and slope stability analyses involving unsaturated and saturated soils. Factors controlling the rate of changes in factor of safety during rainfall and a preventive method to minimize infiltration are highlighted in this paper.

• 환경영향평가
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• 제15권1호
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• pp.67-78
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• 2006

Global warming brings about changes of diverse environmental, especially changes of plant distribution. The purpose of this paper is to examine the relationship between temperature rise and changes of northern limit of vegetation growth in Korea. Bamboos (Phyllostachys) and boundary between the northern type and southern type of garlic (Allium sativum L.) were selected. The data of the distributions of bamboos and garlic are collected by field survey and interviews. Temperature is analyzed from 1904 to 2000. The northern limit of Phyllostachys moves 60-100 km northward, for about 100 years, the period of 1907-2003 and mean temperature of Korea increases about $2^{\circ}C$ during the same period. It means that the northern limit moves 30-50 km northward, for each $1^{\circ}C$ rising of January mean temperature. The boundary between the northern type and southern types of garlic moves northward 40-140 km from 1980s to 2000. The moving width is broad in the west coastal region while the width is narrow in the inland and mountain regions. The mean moving width is about 100 km.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.33-33
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• 2023

In this article, the challenges of Iran and the world are compared to the management of available water resources. Especially in recent years, according to the climatic changes that have occurred all over the world and the changes in the rainfall patterns, and the corresponding changes in the management of water resources, the situation in Iran is being investigated. According to the available information, the amount of water on the planet is estimated to be about 1.36 billion cubic kilometers, which covers about 71% of the earth's surface. However, about 97.5% of the water in the world is salty ocean water and only 2.5% is fresh. Therefore, only 0.025% of the total water on the planet will be usable. According to United Nations statistics, 61% of the world's water consumption is in agriculture, 23% in industry, and 8% for drinking, household, and health purposes. Considering the large number of dams in Iran, only 6% of all dams are used to produce electric energy, which is a significant difference compared to the world (approximately 19%).

• Korean Journal of Acupuncture
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• 제31권3호
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• pp.117-124
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• 2014

Objectives : The purpose of this study is to understand the meaning and the yin-yang properties of the six qi and the three yin and three yang as well as to understand the relationship between the six qi and the three yin and three yang. Methods : As the concept of six qi is the six climatic influences after all, I tried to grasp the yin and yang properties of the six qi on the basis of the meteorology and Yun Qi theory. Based on this I studied the concept and properties of the three yin and three yang. Results and Conclusions: (1) Among the six qi, cold and heat refer to temperature, dryness and dampness to humidity, and wind and ministerial fire to atmospheric pressure. Wind is an ascending air current while ministerial fire is a descending air current. Therefore, wind, heat, and dampness are the yang, and ministerial fire, dryness, and cold are the yin. (2) Three yin and three yang represent changes of ying and yang of all things following six qi changes. Simple deviation of qi can be described by yin and yang, but consequent changes in form required further developed concepts of three yin and three yang. In other words, the changes of the form caused by wind, heat, and dampness are namely reverting yin, lesser yin, and greater yin respectively, while the changes of the form caused by ministerial fire, dryness, and cold are expressed as lesser yang, yang brightness, and greater yang respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제3권4호
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• pp.305-312
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• 1990

The seasonal changes in production, the systems of management and the seasonal climatic and feeding conditions are described for three farms representative of the major areas for growing fine-wool sheep in northern China. At all farms, summer and autumn were seasons of rapid liveweight gain and wool growth. In the winter and spring, during lactation, liveweight declined wool growth decreased by approximately 70%, and fibre diameter by 4 to 8 microns. The wool produced was characterized by a very low clean wool yield (39-51%). Greasy fleece weights ranged from 4.5 to 8.0 kg and average diameter of wool fibres from 20.5 to 23 microns. The number of lambs born per 100 ewes mated ranged from 79 to 95, lamb weights ranged from 3.8 to 4.5 kg, and weaning weights ranged from 17 to 25 kg. Overall, the patterns of sheep production were similar to those found in seasonally arid environments (such as in the mediterranean climatic zone). Yield of clean wool and therefore clean fleece weights were far below those in most other fine-wool producing areas of the world.