• 제목/요약/키워드: decreased forest

검색결과 1,698건 처리시간 0.029초

Phosphorus and Base Cation Inputs through Litterfall Components in Pine Forests after Tree Removal Due to Pine Wilt Disease Disturbance

  • Baek, Gyeongwon;Kim, Seongjun;Kim, Choonsig
    • 한국산림과학회지
    • /
    • 제108권3호
    • /
    • pp.296-301
    • /
    • 2019
  • This study was conducted to measure litterfall and nutrient (P, K, Ca, Mg) inputs under varying degrees of disturbance by pine wilt disease in pine forests in southern Korea. Litterfall was collected to evaluate nutrient responses at different intensities of disturbance (various levels of basal area) by pine wilt disease across 2 years. Phosphorus, Ca, and Mg concentrations in needle litterfall were positively correlated (p < 0.05) with decreased disturbance intensities (increased basal area) depending on the time of sampling, whereas the nutrient concentrations in other litterfall components (branches, bark, reproductive organs, and miscellaneous litterfall) were not significantly correlated (p > 0.05) with the intensity of pine wilt disease disturbance. Dry weight and nutrient inputs through litterfall components decreased linearly with increasing intensity of disturbance by pine wilt disease (p < 0.05), except for the nutrient inputs of branch (K, Ca, Mg) and reproductive organ (K, Ca) litterfall. These results indicate that decreased litterfall across different levels of disturbance may be related to the reduced soil nutrients in pine wilt disease forests.

Immunostimulatory Activity of Syneilesis palmata Leaves through Macrophage Activation and Macrophage Autophagy in Mouse Macrophages, RAW264.7 Cells

  • So Jung Park;Jeong Won Choi;Hyeok Jin Choi;Seung Woo Im;Jin Boo Jeong
    • Journal of Microbiology and Biotechnology
    • /
    • 제33권7호
    • /
    • pp.934-940
    • /
    • 2023
  • Syneilesis palmata (SP) is a traditional medicinal plant. SP has been reported to have anti-inflammatory, anticancer, and anti-human immunodeficiency virus (HIV) activities. However, there is currently no research available on the immunostimulatory activity of SP. Therefore, in this study, we report that S. palmata leaves (SPL) activate macrophages. Increased secretion of both immunostimulatory mediators and phagocytic activity was observed in SPL-treated RAW264.7 cells. However, this effect was reversed by the inhibition of TLR2/4. In addition, inhibition of p38 decreased the secretion of immunostimulatory mediators induced by SPL, and inhibition of TLR2/4 decreased the phosphorylation of p38 induced by SPL. SPL augmented p62/SQSTM1 and LC3-II expression. The increase in protein levels of p62/SQSTM1 and LC3-II induced by SPL was decreased by the inhibition of TLR2/4. The results obtained from this study suggest that SPL activates macrophages via TLR2/4-dependent p38 activation and induces autophagy in macrophages via TLR2/4 stimulation.

한반도의 몇 삼림형에 따른 임토육기물 축종량의 위도적차이에 대해서 (Latitudinal Differences in the Accumulation of Soil Organic Matter in Selected Kroean Forest Types)

  • 임양재
    • Journal of Plant Biology
    • /
    • 제14권1호
    • /
    • pp.5-13
    • /
    • 1971
  • Accumulation of soil organic matter and its vertical distribution at different latitudes in peninsular Korea were studied in the soil of four different forest types viz. Pinus densiflora forest, Castanea forest, Quercus acutissima forest and Carpinus laxiflora forest. Among them, accumulation of soil organic matter in Cheju sites, with a mean annual temperature of 15$^{\circ}C$, was maximum with increasing latitude, soil organic matter concentration decreased. Considering the relationship between concentration of soil organic matter and some climatic conditiions, it seems that concentrations of soil organic matter is a function of annual temperature, especially warmth index or cold index.

  • PDF

기후변화를 고려한 낙엽송 지위지수 추정 (Analysis of the Effect of Climate Change on the Site Index of Larix leptolepis)

  • 김동현;김의경;박상병;김현근;김형호
    • 한국산림과학회지
    • /
    • 제101권1호
    • /
    • pp.53-61
    • /
    • 2012
  • 이 연구는 기후변화를 고려한 낙엽송의 생장모형을 추정한 후 이에 따른 영향을 분석하는 데 있다. 이를 위해 종속변수는 지위지수, 독립변수는 입지, 기상, 토양인자를 설정하였으며, WLS 모형을 이용하여 잣나무의 생장모형을 추정하였다. 이를 토대로 한반도에 적용된 IPCC의 A1B 기후변화 시나리오 따라 $-3.3^{\circ}C$에서 $+3.3^{\circ}C$까지 시뮬레이션한 결과, $-0.8^{\circ}C$를 정점으로 지위지수는 감소하는 것으로 분석되었다. 이러한 결과를 바탕으로 각 시나리오에 따른 지역별 낙엽송 지위지수의 변화를 분석한 결과, 각 시나리오별 낙엽송의 지위지수는 전반적으로 감소하였으나 일부지역에서는 낙엽송의 지위지수가 증가하는 것으로 나타났다. 하지만 기온이 $3^{\circ}C$ 상승했을 때, 지위지수가 증가한 지역 또한 상대적으로 감소하는 것으로 분석되었다.

강원도 삼척 산불피해지역에서 피해목 제거 전과 후의 서식환경 및 설치류 개체군 특성 차이 (Differences in Characteristics of Habitat and Rodent Populations Between Before and After Damaged Tree Removals at Forest Fired Areas in Samcheok, Gangwon Province, Korea)

  • 이은재;이우신;이영근;이명보;임신재
    • 한국산림과학회지
    • /
    • 제97권1호
    • /
    • pp.113-117
    • /
    • 2008
  • 본 연구는 2000년도에 산불이 발생한 강원도 삼척의 침엽수림 지역에서 피해목 처리 전과 후의 서식환경 및 설치류 개체군 특성 차이를 구명하기 위해 실시되었다. 피해목 제거 후 고사목과 수목잔존물의 수는 감소한 반면, 천이 단계의 진행으로 인해 하층 피도량 및 관목의 본수는 증가하였다. 전체 설치류 개체군 밀도, 흰넓적다리붉은쥐 및 대륙밭쥐의 개체군 밀도는 피해목 제거 후 감소하는 경향을 보인 반면, 등줄쥐의 개체군 밀도는 증가하였다. 피해목의 제거로 인한 서식환경의 변화는 설치류의 종 구성을 변화시켰으며, 특히 산림성 설치류에게는 부정적인 영향을 미치는 것으로 판단된다.

The Impact of Program Improvement Using Forest Healing Resources on the Therapeutic Effect: Focused on Improving Index of Greenness for Adolescents

  • Hwang, Joo-Ho;Lee, Hyo-Jung;Park, Jin-Hwa;Kim, Dong-Min;Lee, Kyoung-Min
    • 인간식물환경학회지
    • /
    • 제22권6호
    • /
    • pp.691-698
    • /
    • 2019
  • This study is to examine the effect of improving the forest therapy program for adolescents using forest healing resources (focused on improving index of greenness for adolescents). The participants were 30 students from in the control group that participated in the 2018 program, and 51 students in experimental group that participated in the improved program in 2019. The questionnaire, developed by Korea Forest Welfare Institute, was comprised of items on general matters, index of greenness, restorative environment, positive emotion, negative emotion, facial expression and psychological assessment. The control group had 30 and the experimental group had 49 valid copies of the questionnaires. As a result of the paired sample t-test for each group, the control group showed a significant increase in all categories except restorative environment. In the experimental group, all categories significantly improved to a higher level (p <.01). An independent sample t-test (one-tailed test) was performed to test the effect of the forest therapy program with improved index of greenness. As a result, the index of greenness increased by 0.73 points(t=2.555, p <.01) and restorative environment by 1.01 points (t=2.567, p <.01), showing statistical significance. Negative emotion increased by 0.04 points (t=0.183, p >.05), which was not significant. On the other hand, positive emotion decreased by 0.42 points (t=-1.918, p <.05), facial expression by 0.57 points (t=-1.775, p <.05), and psychological assessment by 0.29 points (t=-0.981, p >.05), showing significance in positive emotion and facial expression. However, all the decreased items showed significant improvements between the pretest and posttest scores of the experimental group.

염포산 산림식생의 군락 구조 및 공간 분포의 경시적 변화 (Changes Over Time in the Community Structure and Spatial Distribution of Forest Vegetation on Mt. Yeompo, Ulsan City, South Korea)

  • 오정학;김준수;조현제
    • 한국산림과학회지
    • /
    • 제109권2호
    • /
    • pp.145-156
    • /
    • 2020
  • 울산광역시의 대표적인 고립된 도시숲인 염포산을 대상으로 2000년과 2018년에 산림식생에 대한 식물사회학적 식생조사를 수행하여 그 구조, 조성 및 공간 분포 변화 경향을 비교하였다. 분석 결과, 총피도(/100㎡)는 거의 변화가 없었으나 자연식생에서는 약 9%의 증가율을 보였다. 구성종의 중요치는 그 순위에 있어서는 다소간의 변화가 있었으며 난대성 수종인 비목나무와 오염내성이 강한 때죽나무가 각각 835%, 269%의 매우 높은 증가율을 보였다. 종풍부도(S)와 종다양도(H')는 각각 약 22%, 약 8%의 감소율을 보였는데 주로 하층 식생 발달에 따라 임상 식생 구성종이 자연 감소한 결과로 판단되며 모두 인공식생이 자연식생에 비해 다소 높은 감소율을 나타내었다. 생활형 조성 체계는 2000년과 2018년 모두 'MM-R5-D4-e'로 동일하게 나타났다. 전체 산림식생의 유사도(Jaccard 계수)는 약 75%로 종구성적 특성이 거의 동질적으로 나타났다. 지표종은 2000년 16종에서 2018년 7종으로 9종이 감소하였으며 대부분 교란에 민감한 반지중식물(H), 지중식물(G) 그리고 일년생식물(Th) 등 초본식물이었다. 상관식생 유형 간 공간 분포 면적은 큰 변화가 없었으며, 산림경관 요소인 패치(patch)의 개수는 2000년 537개에서 2018년 721개로 약 25%의 증가율을 보인 반면, 그 평균 크기는 2000년 1.28 ha에서 2018년 1.03 ha로 약 20%의 감소율을 보였다.

The Effects of Thinning on Fine Root Distribution and Litterfall in a Pinus koraiensis Plantation

  • Park, Byung-Bae;Lee, Im-Kyun;Yang, Hee-Moon
    • Journal of Ecology and Environment
    • /
    • 제32권3호
    • /
    • pp.159-165
    • /
    • 2009
  • The purpose of this study was to investigate the effects of thinning on fine root biomass and vertical distribution. and litterfall amount in a 50 year old Pinus koraiensis plantation in Chuncheon, Kangwon Province. Fine root (< 2 mm in diameter) biomass ($367\;g/m^2$) in the site 'OC_75', thinning once in 1975, was 68% of those in the site 'CON', no thinning after planting, and in the site 'TC_00', thinning twice in 1975 and 2000. There were no significant differences of dead roots among treatments. Diameter $0{\sim}1\;mm$ roots were vertically decreased only in the TC_00 site. The litterfall was very similar between OC_75 ($5.2\;Mg\;ha^{-1}\;yr^{-1}$) and TC_00 ($4.7\;Mg\;ha^{-1}\;yr^{-1}$), but the composition of litterfall was different: The proportion of leaves and branches was 80% and 13% in OC_75 and 56% and 36% in TC_00, respectively. Reduction of P. koraiensis density by thinning decreased leaf litter as well as fine roots of P. koraiensis, but increased fine roots production by neighboring understory plants offset the reduction of fine roots of P. koraiensis. We suggest that belowground as well as aboveground responses, including both over- and understory vegetation, should be considered to measure the responses of trees in thinned forest ecosystems.

임도 노선측량 작업의 작업분석 (Work analysis of route survey work on forest-road)

  • 권형근;이준우;최성민;염인환
    • 농업과학연구
    • /
    • 제40권3호
    • /
    • pp.209-214
    • /
    • 2013
  • This study examined the work time, work posture, and work intensity for the actual measurement step in forest road the design work that was being carried out. The measurement of the forest road was being carried by a team of three workers and a team of four workers. The examination of work time found that the measurement of 1km took about 8 hours for the four-worker team and 12 hours for the three-worker team. The examination of work intensity found that the energy metabolic rates of the three-worker team were lower than four-worker team. Because their energy consumption per minute decreased as their work time and rest time increased. Furthermore, when appropriate rest time was applied according to work time, the energy metabolic rate decreased and the work intensity became lower. The four-worker team was more advantageous from the time and cost aspects of the forest road measurement work. Furthermore, as the rest time was very low compared to the work time, more efficient forest road measurement work would be possible if the work intensity was lowered by considering the rest time when calculating the standard work time.

건우기에 산림토양의 화학성분의 변화 (THE CHANGES OF CHEMICAL PROPERTIES OF FOREST SOILS IN DRY AND WET SEASONS)

  • CHA, Jong Whan
    • Journal of Plant Biology
    • /
    • 제7권2호
    • /
    • pp.1-8
    • /
    • 1964
  • Cha, Jong Whan (Dept. of Biology, Graduate School, Dong Kuk Univ.) The changes of chemical properties of forest soils in dry and wet seasons. Kor. Jour. Bot. VII(2): 1-8, 1964. Soil selected for the present investigation was collected from a mountain of the Forestry Experiment Station of the vicinity of Seoul. The forest communities studied were three forest and a unplanted soils. The soil samples were obtained from each forest type during dry and wet seasons. And these samples were collected from four horizons of all communities respectively. It was showed that exchangeable hydrogen was increased by rainfall, and total exchangeable base decreased in the same way. The content of nitrogen is washed away by rainfall, especially ammonium nitrogen was highly significant between dry and wet season. On the contrary, organic matter and available phosphorus were of no significant difference between dry and wet seasons. The values of pH appeared a different response in dry and wet seasons according to the plant communities. The needle-leaved forest soils showed more acidity than the broad-leaved forest soils, and the least acidity in open places. All nutrients in soil studied gradually decreased down the profiles. According to statistical analyses of the soil components among all soil horizons, total exchangeable bases in wet season indicated only significant at 1%. Exchangeable hydrogen and organic matter of the soil in dry season was particularly very low with increased depth in the profile. The fertility level of most forested soils selected for the present investigation is low according to chemical tests for available nutrient elements.

  • PDF