• Title/Summary/Keyword: matter change

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Characteristics of Macroinvertebrates Food Webs affected by Dry Channel in an Intermittent Stream System of the Echi River in Japan

  • Shin, Hyun-Seon;Nozomi, Amahashi;Na, Young-Eun;Park, Hong-Hyun;Cho, Kwang-Jin;Seo, Ye-Ji;Osamu, Mitamura
    • Journal of Climate Change Research
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    • v.6 no.3
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    • pp.167-173
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    • 2015
  • The purpose of study is to identify trophic pathways from organic matter to macroinvertebrates in terms of the consumer and to characterize the food webs in an intermittent stream system of the Echi River in Japan. The ${\delta}^{13}C$ values of macroinvertebrates and their potential food sources indicated the scraper (Psephenoides spp., Ecdyonurus levis) and collector-gatherer (Ephemera strigata, Paraleptonphlebia chocolata) feed on periphyton and POM (particulate organic matter) in situ. Davidius lunatus, and Hexatoma spp., which were identified as predators, may feed upon Ephemera strigata and Stenelmis larvae, respectively. At station characterized by seepage water, the ${\delta}^{15}N$ values of Ecdyonurus levis, Lymnaea auricularia, and Rhyacophila nigrocephala larva probably showed relatively lower values according to its diets. Even in homogenous species, the trophic pathways of macroinvertebrates in situ exhibited considerable variation; this reflected the trophic pathways from organic matter to the consumer depending on habitat characteristics in stream.

Change of Organic Matter Decomposition Rates and Greenhouse Gas Emission of the Soil of Gyeongan Stream under Different Environmental Conditions (환경 조건 차이에 의한 경안천 토양의 유기물 분해속도와 온실가스 발생 변화)

  • Choi, In Young;Kang, Min Kyoung;Choi, Jung Hyun
    • Korean Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.75-85
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    • 2013
  • This study investigated the effects of organic matter decomposition on the emission of greenhouse gas under the influence of environmental factors such as change of climate condition ($CO_2$ concentration and temperature), vegetation, and N concentration in the soil of Gyeongan stream in the laboratory. The experimental results showed that organic matter decomposition and $CH_4$, $CO_2$ flux were influenced by changes of complex environmental conditions. Organic matter decomposition rate was affected by changes of climate condition with N concentration and climate condition with vegetation. Through the results of $CH_4$, $CO_2$ flux, $CH_4$ flux was affected by change of climate condition with N concentration and climate condition with vegetation and affected by the presence of vegetation and N concentration. $CO_2$ flux was affected by change of climate condition with vegetation and vegetation with N concentration. According to results of the study, change of (1) climate conditions, (2) vegetation, and (3) N concentration, each have an effect on organic decomposition rate, that also influences emission of greenhouse gas. It is known that climate change is related to an increase in greenhouse gasses in the atmosphere However, additional study will be needed whether vegetation could remove positive effect of nitrogen addition in soil since this study shows opposite results of organic matter decomposition in response to the nitrogen addition.

Distinguishing the Effects of Environmental Stress and Forest Succession on Changes in the Forest Floor

  • Arthur, Mary A.;Ruth D. Yanai
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.83-88
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    • 2000
  • When interpreting change over time in forest ecosystems, distinguishing the effects of forest succession from the effects of environmental stress can be difficult. The result may be a simplistic interpretation. citing a specific successional or environmental cause of forest change when both types may be occurring. We present two case studies of changes in the forest floor in northern hardwoods. First, the belief that 50% of soil organic matter is lost in the first 20 years after logging was based on a study comparing northern hardwood stands of different ages. We resampled a series of 13 such stands after an interval of 15 years, and found that the young stands were not, in fact. losing organic matter as rapidly as predicted from the original chronosequence study. The pattern of higher organic matter content in the forest floors of older stands compared to young stands could be equally well explained by changes in logging practices over the last century as by the aging of the stand. The observed pattern of forest floor organic matter as a function of stand age was previously interpreted as a successional pattern, ignoring changes in treatment history. In the second case study, observed losses of base cations from the forest floor were attributed to cation depletion caused by acid rain and declining calcium deposition. We found that young stands were gaining base cations in the forest floor; losses of base cations were restricted to older stands. Differences in litter chemistry in stands of different ages may explain some of the pattern in cation gains and losses. In this case, the contribution of successional processes to cation loss had been overlooked in favor of environmental stress as the dominant mechanism behind the observed changes. Studies of environmental stress use repeated measures over time. but often don't consider stand age as a factor. Studies of successional change often assume that environmental factors remain constant. We were able to consider both forest succession and external factors because we repeatedly sampled stands of different ages.

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Analysis of Examples Categorized by Function in the 'States of Matter' Chapter of Third Grade Science Textbooks and Students' Conceptions (초등학교 3학년 '물질의 상태' 단원에 제시된 예의 기능별 유형 분석 및 학생들의 이해)

  • Paik, Seounghey;Choi, Jungin;Park, Eunju
    • Journal of The Korean Association For Science Education
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    • v.33 no.7
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    • pp.1273-1284
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    • 2013
  • The purpose of this study was to analyze the examples represented in school science textbooks by the function types for students' scientific conceptions. According to the framework of analysis, we selected lacking examples in the textbooks, and developed a questionnaire for students. The questionnaire was applied to 157 third grade students to survey their conceptions related to matter states and change of states. The ratio of students' scientific conceptions related to solid the state was high because distinct examples were represented in the textbook. However, the ratios of students' scientific conceptions related to the liquid and gas states were low because there were no distinct examples in the science textbook. Contrast examples and expansive examples of liquid and gas such as fog and steam need to be represented in science textbooks in order to help students construct scientific conceptions of matter states and change of states.

Legal Doctrines for the U.S. Federal Courts and the International Investment Arbitral Tribunals in Adjudicating the Climate Change Disputes

  • Shin, Seungnam
    • Journal of Arbitration Studies
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    • v.32 no.3
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    • pp.3-27
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    • 2022
  • Climate change is a man-made disaster that has become a major global concern today. With increasingly visible symptoms of climate change in recent years, it has become evident that climate action can no longer be dismissed as a mere matter of choice, but as a matter of survival for the human being. To address the impending climate change crisis in a collaborative and sustainable manner, the international community has been taking various measures including Kyoto protocol and the Paris Agreement. With respect to the private investor's project investment in line with international agreements on climate change, recently we have seen multiple legal judgments which clearly indicate the subject of judicial responsibility for investment in climate change related projects. However, in order to hold judicial responsibility occurring during the implementation of climate change related projects, a causal relationship between the responsible entities and clear responsibility must be demonstrated, and applicable institutional arrangements need to be arranged. It may be the right time for global community to consider shifting not only to human ethical obligations but also legal obligations. In this regard, concerned governments should consider legislating arbitration laws, regulations, and institutional arrangements in more specific and applicable manner.

MR Imaging and Histological Findings of Experimental Cerebral Fat Embolism in Cats

  • Park Byung-Rae;Ko Seong-Jin;Kim Hwa-Gon
    • Biomedical Science Letters
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    • v.10 no.3
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    • pp.285-291
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    • 2004
  • To determine the magnetic resonance (MR) imaging findings and natural history of cerebral fat embolism in a cat model, and to correlate the MR imaging and histologic fmdings. Intemel carotid artery of 11 cats was injected with 0.1 ml of triolein. T2-weighted, T1-weighted and Gd-enhanced T1-weighted images were obtained serially for 2 hours, 1 days, 4 days, 1 week, 2 weeks and 3 weeks after embolization. Any abnormal signal intensity was evaluated. After MR imaging at 3 weeks, brain tissue was obtained for light microscopic (LM) examination using hematoxylin-eosin (HE) and Luxol fast blue staining, and for electron microscopic examination. The LM examination with HE staining revealed normal histological findings in the greater part of an embolized lesion. Cystic change was observed in the gray matter of 8 cats, while in the gray and white matter of 3 cats. At LM examination, Luxol fast blue, staining demonstrated demyelination around the cystic change occurring in the white matter, and EM examination of the embolized cortex revealed sporadic intracapillary fat vacuoles (n=11) and disruption of the blood-brain barrier (n=4). Most lesions were normal, however, and perivascular interstitial edema and cellular swelling were mild compared with the control side. The greater part of an embolized lesion showed reversible findings at MR and histological examination. Irreversible focal necrosis was, however, observed in gray and white matter at weeks 3.

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A Study on the Development of a Modular Multimedia Instruction Materials for the 1.earning of Molecular Unit in Nature Instruction of Elementary School (초등학교 자연과의 분자 단원 학습을 위한 모듈식 멀티미디어 교수학습 자료 개발 연구)

  • 박종욱;김도욱
    • Journal of Korean Elementary Science Education
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    • v.19 no.1
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    • pp.101-112
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    • 2000
  • The purpose of this study was to develop the modular multimedia instructional materials emphasizing the particulate nature on the realm of matter in elementary science classes. Features of the material are as follows: 1 To be in focus on particulate model named 'phenomenal magnifying glasses' in order to change the student's belief system of continuous matter into the belief system of particulate matter . The 'phenomenal magnifying glasses' is a new instructional strategy designed to change into the view of particulate matter through facilitating the reflective thinking resulted from the simultaneous consideration of experimental phenomena(macroscopic world) and particulate model(microscopic world). 2. To introduce modular system into the instructional materials, which was consisted of 14 subunits according to the sequential instruction unit of 'molecule and molecular motion'. Each subunit was composed of 5 types of modules(module 1: motivation, module 2: experimental result, module 3: discussion, module 4: phenomenal magnifying glasses, module 5: related experiment) 3. The multimedia program was composed of 36 kinds of experimental animation and 59 kinds of computer animation materials combined with text resources, photographic materials and sounds.

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Regional Gray Matter Volume Reduction Associated with Major Depressive Disorder: A Voxel-Based Morphometry

  • Tae, Woo-Suk
    • Investigative Magnetic Resonance Imaging
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    • v.19 no.1
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    • pp.10-18
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    • 2015
  • Background and Purpose: The association between the low emotional regulation and the brain structural change of major depressive disorder (MDD) has been proposed, but the voxel-based morphometry (VBM) studies on female MDD are rare. The purpose of the present study was to show the regional volume changes of gray matter (GM) in female patients with MDD by optimized VBM. Methods: To control subjects homogeneity, twenty female MDD patients and age, sex matched 21 normal controls were included for the VBM analysis. To identify the change of regional gray matter volume (GMV), the optimized VBM was performed with T1 MRIs. The amounts of gray/white matter and intracranial cavity volumes (ICV) were measured. The analysis of covariance (ANCOVA) and partial correlation analyses covariate with age and ICV were applied for VBM. Results: The age and ICV distributions were similar between the two groups. In the ANCOVA, the total GMV of MDD was smaller than that of normal controls. In the VBM, regional GMV was relatively decreased in the limbic system (amygdalae, ambient gyri, hippocampi heads, subiculum, posterior parahippocampal gyri, pulvinar nuclei, dorsal posterior cingulate gyri, and left pregenual cingulate gyrus). The lingual gyri, short insular gyri, right fusiform gyrus, and right inferior frontal gyrus were also showed decreased regional GMV. Conclusion: The results of this study indicate that the female MDD is mainly associated with the structural deficits of the limbic system and limbic system related cortices, which were known to the center of emotions.

Space-time and The theory of Eumyang-ohaeng -way of thinking in the standpoint of Oriental Medicine- (시공(時空)과 음양오행(陰陽五行) -한의학의 사고체계-)

  • Back, Sang-Ryong
    • Korean Journal of Oriental Medicine
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    • v.9 no.2
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    • pp.17-27
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    • 2003
  • Eumyang-ohaeng[陰陽五行-Eumyang and five phases], as a standing rule that establishes the theory of Oriental medicine and origin of the oriental philosophy, it provides the perspective of the oriental medicine's outlook of the world. Without knowing the Eumyang-ohaeng, we cannot discuss Oriental medicine, nor can we understand the oriental way of thinking. Time and Space is what the human being created in order to explain the existence and change of matters. There is a common denominator between this universal concept of time and space and the theory of Eumyang-ohaeng. Consequently this paper investigates how characteristics of Eumyang-ohaeng and that of time and space matches Eumyang represents all matter and its characteristic, by comparison with each other space, and Ohaeng shows the change of matter with time gradually and sequancely. But this separation is only a separation by words, they really melt into one like two sides of a coin is actually just one coin. After all the theory of Eumyang-ohaeng is a theory that leads us to realize time and space, matter and power are all just one. So consequently, despite the difference in mass or size or longevity of matters, Eumyang-ohaeng pulls all matter into one body. It's why Eumyang-ohaeng is defined as the unified theory of time and space.

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Chemical Budgets in Intensive Carp Ponds

  • Peng Lei;Oh Sung-Yong;Jo Jae-Yoon
    • Fisheries and Aquatic Sciences
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    • v.6 no.4
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    • pp.194-202
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    • 2003
  • Budgets for water, nitrogen, and chemical oxygen demand (COD) were determined in two 0.012 ha earthy-bottom ponds stocked with Israeli strain common carp at an initial stocking density of $20\;fish/m^3$. Total ammonia nitrogen (TAN) concentrations increased continuously but later decreased in pond A as a consequence of high nitrification. COD concentrations increased during the experimental period due to the accumulation of feed input. Nutrient budgets showed that feed represented $94-95\%$ of nitrogen input and about 99% of organic matter input. Fish harvest accounted for $40\%$ of nitrogen and organic matter input. Seepage and water exchange removed $15-17\%$ of nitrogen input but only $1-2\%$ of organic matter. Draining of the ponds removed $20-26\%$ of input nitrogen, mostly in inorganic forms, but removed only minus organic matter. Fish and water column respiration accounted for $39\%$ of organic matter input, and benthic respiration accounted for $7-12\%$ of organic matter input. No significant change of nitrogen and organic matter in both pond bottoms were found during the three-month growth period. The unrecovered input nitrogen, about $6.3-13\%$, was lost through denitrification and ammonia volatilization. On a dry matter basis, fish growth removed $31\%$ of total feed input and left $69\%$ as metabolic wastes.