• 제목/요약/키워드: Forest decline

검색결과 141건 처리시간 0.025초

Atmospheric Quality, Soil Acidification and Tree Decline in Three Korean Red Pine Forests

  • Lee, Choong-Hwa;Lee, Seung-Woo;Kim, Young-Kul;Cho, Jae-Hyoung
    • The Korean Journal of Ecology
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    • 제26권2호
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    • pp.87-89
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    • 2003
  • Although a forest damage of large area due to air pollution has not yet been found in Korea, declines of Korean red pine (Pinus densiflora Sieb. et Zucc.), the most common coniferous species, have been locally reported. To evaluate the effect of air pollution and acid deposition on the forests, SO$_2$ concentration, acid load, soil pH and tree decline were monitored for 13 years from 1988 to 2001 in Namsan, Doowang and Gyebangsan with the gradient of air pollution. During the study period, annual mean SO$_2$ concentration in Namsan, Doowang and Gyebangsan were 14 ppb, 13 ppb and 6 ppb, respectively. Annual mean acid loads in Namsan and Doowang were three to four times more than that in Gyebangsan. As respected, forest surface soils in Namsan and Doowang were acidified to pH 4.1 and 4.3, whereas that in Gyebangsan showed normal value as pH 5.4. On the other hand, decline degrees of Korean red pines in Namsan and Doowang in both 1996 and 2001 were higher than those in Gyebangsan. It is reasonable that the severer tree declines in Namsan and Doowang could be closely related with the higher air pollution, acid load, and the effects (possibly Ca deficit and Al toxicity) of soil acidification.

Species diversity, relative abundance, and decline of flying insects in a fragmented forest in Futa Akure, Ondo State, Nigeria

  • Temitope A. Olatoye;Ohseok, Kwon;Kayode L. Akinwande
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제5권1호
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    • pp.10-20
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    • 2024
  • The study investigated species diversity, relative abundance, and decline of flying insects and plants within a fragmented forest in the Federal University of Technology Akure (FUTA), Ondo State, Nigeria. It is known that habitat fragmentation can reduce biodiversity. Thus, it is important to perform comprehensive assessments to understand implications of the habitat fragmentation for flora and fauna. Species richness and abundance of flying insects and plants across fragmented forest patches were quantified using field surveys and taxonomic identification. This study revealed shifts in species diversity, with fragmented areas exhibiting reduced biodiversity compared to contiguous forest ecosystems. Flying insects crucial for ecosystem functioning and pollination services demonstrated decreased species richness and relative abundance within fragmented habitats. This decline was attributed to habitat loss, altered microclimates, and limited movement pathways known to hinder insect dispersal. Similarly, plant species richness and abundance showed decline in fragmented forest due to disrupted mutualistic interactions with pollinators, altered nutrient cycling, and increased competition among plant species. This study underscores the importance of maintaining intact forest habitats to sustain healthy ecosystems and preserve biodiversity. Effective conservation strategies should focus on habitat connectivity, reforestation efforts, and protection of essential ecological corridors to mitigate effects of fragmentation. In conclusion, this investigation provides empirical evidence for effects of habitat fragmentation on flying insects and plants in a forest ecosystem in FUTA Akure, Nigeria. Findings emphasize an urgency of adopting conservation measures to safeguard these invaluable components of biodiversity and ecosystem stability in the face of ongoing habitat loss and fragmentation.

Effects of Strong Wind and Ozone on Localized Tree Decline in the Tanzawa Mountains of Japan

  • Suto, Hitoshi;Hattori, Yasuo;Tanaka, Nobukazu;Kohno, Yoshihisa
    • Asian Journal of Atmospheric Environment
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    • 제2권2호
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    • pp.81-89
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    • 2008
  • The numerical simulation of wind and ozone ($O_3$) transport in mountainous regions was performed with a computational fluid dynamics technique. A dry deposition model for $O_3$ was designed to estimate $O_3$ deposition in complex terrain, and the qualitative validity of the predicted $O_3$ concentration field was confirmed by comparison with observed data collected with passive samplers. The simulation revealed that wind velocity increases around ridge lines and peaks of mountains. The areas with strong wind corresponded well with the sites of tree decline at high altitudes, suggesting that it is an important factor in the localization of tree/forest decline. On the other hand, there is no direct relationship between forest decline and $O_3$ concentration. The $O_3$ concentration, however, tends to increase as wind velocity becomes higher, thus the $O_3$ concentration itself may be a potential secondary factor in the localized decline phenomena. While the diffusion flux of $O_3$ is not related to localized tree decline, the pattern of advection flux is related to those of high wind velocity and localized tree decline. These results suggest that strong wind with large advection flux of $O_3$ may play a key role in the promotion of tree/forest decline at high mountain ridges and peaks.

산성 강우에 의한 수목의 쇠퇴현상(II) - 양이온을 중심으로 - (Decline of Trees by Acid Rain - Especially Cation -)

  • 이총규;황진형;김종갑
    • The Korean Journal of Ecology
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    • 제28권6호
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    • pp.383-387
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    • 2005
  • 대기오염 및 산성비의 영향을 받고 있는 공단지역(온산공단)과 도시 근교 지역(진주), 농촌 지역(함안)으로 나누어 각 산림지역 내의 임외우와 수관통과우에 대한 강우의 이온 특성과 곰솔림의 쇠퇴와의 관계를 분석하였다. 임외우와 수관통과우의 $Ca^{2+}$은 공단 지역이 농촌지역에 비해 각각6배, 2배 이상 높게 나타났다 해송의 쇠퇴도와 강우의 양이온 성분간의 상관분석을 실시한 결과, 곰솔의 쇠퇴도와 강우의 pH(r = -0.84, p<0.01), $Ca^{2+}$ (r=-0.80, p<0.01) 이온 간에는 유의적인 부의 상관이 인정되었다.

Effects of the Forest Healing Program on Depression, Cognition, and the Autonomic Nervous System in the Elderly with Cognitive Decline

  • Lim, Young-suwn;Kim, Jaeuk;Khil, Taegyu;Yi, Jiyune;Kim, Dong-jun
    • 인간식물환경학회지
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    • 제24권1호
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    • pp.107-117
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    • 2021
  • Background and objective: The purpose of this study is to investigate the effect of a forest healing program in terms of depression, neuropsychological and physiological benefits for the elderly. Methods: For this purpose, we developed a forest therapy program for the elderly who are vulnerable to dementia and conducted a total of 11 sessions of forest therapy activities in a forest once a week. We measured the changes in depression, resting-state Electroencephalography(EEG) and heart rate variability (HRV) before and after the program. There were 60 subjects aged over 65 yesrs old. 30 subjects participated in the forest therapy program, and the other were in the control group. The Geriatric Depression Scale was used to measure the level of depression, neuroNicle FX2 (Laxtha, Korea) was used to measure the resting-state EEG, and photoplethymogram (ubpulse T1, Laxtha, Korea) was used to measure the HRV. Results: The results showed that the depression index of the experimental group improved with statistical significance after the program (experiment group = 3.267 decrease of the mean). In the EEG measurement, the alpha-peak frequency at rest (experimental group = 0.227 Hz increase of the mean) was improved (mean increase = 0.23 in the experimental group, p < .05). The high frequency of HRV, which represents the parasympathetic nerve activity of the body's autonomous response, was also significantly improved (mean increase = 0.396 in the experimental group, p < .05). Conclusion: The results suggest that the forest therapy program can reduce the cognitive, psychological and physical risk factors of dementia for the elderly at risk of cognitive decline. Therefore, forest therapy activities may be suitable for the prevention of dementia in the elderly.

서울시 소나무림의 생태적 특성에 따른 관리방안 연구 (Management Plan to Consider Ecological Characteristic of Pinus densiflora Community in Seoul)

  • 이수동;이경재;최진우
    • 한국환경생태학회지
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    • 제23권3호
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    • pp.258-271
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    • 2009
  • 외부환경 변화와 천이의 영향으로 쇠퇴현상이 나타나고 있는 서울시 소나무림의 식생환경을 개선하고자 교목층 우점종의 경쟁관계, 하층식생내 경쟁종 출현 유무, 관리정도 등에 근거하여 유형을 구분하고 생태적 관리방안을 제안하였다. 서울시 소나무림을 생태적 특성에 따라 분류하면 소나무순림에 속하는 토지극상림(26.1%)과 소나무순림(21.5%), 소나무와 타 수종이 경쟁하는 소나무-신갈나무림(28.0%), 소나무-리기다소나무림(13.1%), 소나무-상수리나무림(4.2%)등으로 구분되었다. 이들 유형에 대한 정밀한 식생조사 결과, 토지극상, 답압피해, 식생관리로 인해 교목층과 하층에 경쟁종이 출현하지 않아 소나무림 유지가 가능한 4개 군집은 하층식생 보완 등 소극적인 관리가 필요하였다. 반면 교목층과 하층에 소나무와 경쟁수종인 낙엽성 참나무류와 외래종이 출현하는 4개 군집은 생태적 지위가 동일한 경쟁종관리, 하층식생 도입 등 적극적인 관리기법을 적용해야 소나무군집을 유지할 수 있을 것이다.

MaxEnt 모형을 이용한 소나무 잠재분포 예측 및 환경변수와 관계 분석 (Predicting the Potential Distribution of Pinus densiflora and Analyzing the Relationship with Environmental Variable Using MaxEnt Model)

  • 조낭현;김은숙;이보라;임종환;강신규
    • 한국농림기상학회지
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    • 제22권2호
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    • pp.47-56
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    • 2020
  • 본 연구는 기후변화에 따른 소나무 잠재분포변화 예측 및 환경요인과의 관계를 파악하기 위한 목적으로 수행되었다. 입력자료인 종속변수는 1:5,000 임상도에서 추출한 소나무 출현자료를 사용하였으며, 독립변수는 RCP 시나리오 기후자료 및 임상도, 입지도에서 추출한 기후, 입지, 생육환경자료 등 총 14개의 환경요인 변수를 사용하였다. 이러한 입력자료를 바탕으로 생태적 지위 개념을 기반으로 한 종 분포 모형 중 하나인 MaxEnt (Maximum Entropy Modeling) 모형을 구동하여 미래의 소나무 잠재분포를 예측하였다. 분석결과 training AUC (Area Under Curve)가 0.79로 우수한 수준의 정확도를 보였으며 현존 소나무 분포 자료와 유사한 현재 잠재분포 결과를 보였다. RCP 시나리오를 적용한 결과 소나무 잠재분포지는 시간이 지남에 따라 지속적으로 감소할 것으로 나타났으며 RCP8.5 기준으로 2050년과 2070년에 각각 11.1%, 18.7%의 잠재분포지가 줄어들 것으로 예측되었다. 입력자료의 소나무 잠재분포 판단에 대한 기여도는 계절기온, 고도, 겨울철 기온 등이 높게 나타났다. 본 연구의 결과는 기후변화로 인한 소나무림 보전 및 대책 수립을 위한 기초자료로 활용될 것으로 판단된다.

Impacts of Close-to-nature Management Technology on the Korean Pine Soil Chemical Properties in Northeast China

  • Wu, Yao;Qin, Kailun;Zhang, Jinfu;Li, Fengri
    • Journal of Forest and Environmental Science
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    • 제29권4호
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    • pp.300-306
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    • 2013
  • Based on the guiding ideology of "Close-to-nature forestry", the soil chemical properties of Korean pine (Pinus koraiensis) plantation forest which was early done by canopy gap control were analyzed of Liangshui nature reserve in northeastern China. The results indicated that the nurture of forestry crevice diaphanous tended to improve the soil nutrient contents and significant differences of soil nutrients existed among different levels of soil for the same forest type of Korean pine. At 0< $H{\leq}20$ cm layer, the content of available nitrogen, available phosphorus, available potassium, total nitrogen and total phosphorus in artificial pure Korean pine forest are 640.28 $mg{\cdot}kg^{-1}$, 7.54 $mg{\cdot}kg^{-1}$, 275.91 $mg{\cdot}kg^{-1}$, 1.114% and 0.075%, they all higher than the other kinds of forests and for average 1.1 times, 1.4 times, 1.3 times, 1.6 times and 1.2 times. From the layer of $0<H{\leq}20$ cm to 20 cm < $H{\leq}40$ cm, soil nutrient indicators showed various degrees of decreasing in which organic matter had the greatest decline, decreasing by 170.64% while PH had the lowest decline, decreasing by 4.66%.