• 제목/요약/키워드: R-trees

검색결과 481건 처리시간 0.023초

정금나무 열매의 총 페놀 함량 및 항산화활성 분석 (Analysis of Total Phenolic Content and Antioxidant Activity from Fruits of Vaccinium oldhamii Miq.)

  • 김혜수;김문섭;김세현;윤경원;송정호
    • 한국산림과학회지
    • /
    • 제102권4호
    • /
    • pp.566-570
    • /
    • 2013
  • 정금나무의 기능성 품종을 육성하기 위하여 정금나무 선발 5개체의 열매에 대한 항산화 활성을 측정하였으며, 항산화 성분인 총 페놀 함량을 측정하였다. 총 페놀 함량은 gallic acid를 기준물질로 하여 분석한 결과 15.8~19.9 mg/g 범위로 전체 평균 17.9 mg/g을 나타냈으며, DPPH free radical 소거활성은 400 ppm의 농도에서 69.1~91.4% 범위로 전체평균 84.2%를 나타내었다. 환원력은 0.56~0.96 범위로 전체 평균 0.79를 나타내었다. 상관분석 결과 DPPH free radical 소거활성과 환원력에서 상관계수가 0.969로 매우 높은 정의 상관관계를 나타내었다.

도심 녹음수의 체감온도지수(WBGT) 조절효과 (The Effect of Urban Shade Trees on the WBGT(Wet Bulb Globe Thermometer Index))

  • 주민진;이춘석;류남형
    • 한국조경학회지
    • /
    • 제32권3호
    • /
    • pp.51-59
    • /
    • 2004
  • Focusing on WBGT(Wet Bulb Globe Thermometer Index) according to the LAI(Leaf Area Index) variation of trees, this study verifies the effects of urban shade trees on the outdoor thermal environment. As for methodology, air$.$globe temperature, air humidity and WBGT were measured under three shade trees whose LAIs were 2.1, 4.0 and 8.2 respectively at midday(12:00-13:00) of 14 sunny days from the 4th through the 29th day of September 2003. Those factors were also measured at the unshaded areas and compared with the values of shaded areas. The measured site was paved with interlocking concrete bricks. The measurements were analyzed through the ANCOV A(Analysis of Covariance) and the regression routines of SPSS11 for windows (SPSS Inc., 2001). The major findings were as follows. 1. The direct correlation between WBGT and LAI was very low. On the contrary, the WBGT showed close correlation with air$.$globe temperature and air humidity, and the LAI also showed very close correlation with globe temperature. These results tell that dominant shading effect by the tree is on the screening of direct solar radiation which lower the globe temperature and WBGT consequently. 2. While the average globe temperatures and WBGT at unshadowed area were 40.4$^{\circ}C$ and 26.2$^{\circ}C$ respectively, the former under the shade tree with LAI 2.1, 4.0 and 8.2 were 34.5$^{\circ}C$, 32.6$^{\circ}C$ and 30.2$^{\circ}C$, and the latter were 24.6$^{\circ}C$, 24$^{\circ}C$ and 23.4$^{\circ}C$ respectively. 3. The relationship between LAI(x) and WBGT(y) can be presented with the following equation: y = 24.23+1.53 $e^{-x}$+0.36x $e^{-x}$+0.46 $x^2$ $e^{-x}$ ($R^2$ =.98) =.98)

Richness of Forest Stands and Atmospheric Carbon Dioxide Storage in Urban Institutional Lands of Bukavu, D.R. Congo

  • KADIATA, Bakach D.;NDAMIYEHE, J.B. Ncutirakiza
    • Journal of Forest and Environmental Science
    • /
    • 제33권2호
    • /
    • pp.79-90
    • /
    • 2017
  • Improving the urban environmental quality relies mainly on the increasing of urban forests capacity to store carbon dioxide. This study assesses the floristic diversity of urban institutional lands in Bukavu and their potential to reduce atmospheric $CO_2$. An exhaustive inventory over three sites ($Coll{\grave{e}}ge$ Alfajiri, $Cath{\acute{e}}drale$ Notre-Dame de la Paix and Institut $Sup{\acute{e}}rieur$ $P{\acute{e}}dagogique$) of Bukavu led to the identification of 1,113 trees of which the diameter at breast height (1.30 m) ranged from 4.9 to 161 cm. Results reveal a floristic diversity made up of 4 families of conifers with 4 species and 14 of broadleaves with 21 species. Average densities were of $54trees\;ha^{-1}$ and $5.21m^2\;ha^{-1}$ of basal area. Urban-based allometric equations used yielded up to 312.8 tons of carbon stored in trees aboveground biomass equivalent to 1,147.9 tons of $CO_2$ reduced from the atmosphere over the three sites. The rate of carbon storage reaches $15.1tons\;ha^{-1}$. Thus, trees of the three institutional sites in Bukavu play an important role in reducing atmospheric $CO_2$ and contribute, thereby, to mitigate global climate change effects. Given the current environmental challenge associated with high population growth rate in cities, the urban forest ecosystem in DRC requires to be extended and further investigation.

Individual Tree Growth Models for Natural Mixed Forests in Changbai Mountains, Northeast China

  • Lu, Jun;Li, Fengri
    • 한국산림과학회지
    • /
    • 제96권2호
    • /
    • pp.160-169
    • /
    • 2007
  • The data used to develop distance-independent individual models for natural mixed forests were collected from 712 remeasured permanent sample plots (25,526 trees) of 10-year periodic from 1990 to 2000 in Baihe Forest Bureau of Changbai Mountains, northeast China. Based on analyzing relationship between diameter increment of individual trees with tree size, competitive status, and site condition, the diameter growth models for individual trees of 15 species growing in mixed-species uneven-aged forest stands, that have simple form, good predicting precision, and easily applicable, were developed using stepwise regression method. The main variables influencing on diameter increment of individual trees were tree size and competition, however, the site conditions were not significantly related with diameter increment. The tree size variables (lnDBH and $DBH^2$) were the most significant and important predictors of diameter growth existing in all 15 growth models. The diameter increment was directly proportional to tree diameter for each species. For the competitive factors in growth model, the relative diameter (RD), canopy closure (P), and the ratio of diameter of subject tree with maximum diameter (DDM) were contributed to the diameter increment at a certain extent. Other measures of stand density, such as basal area of stand (G) and stand density index (SDI), were not significantly influenced on diameter increment. Site factors, such as site index, slope and aspect were not important to diameter increment and excluded in the final models. The total variance explained by the final models of squared diameter increment ($R^2$) for all 15 species ranged from 35% to 72% and these results compared quit closely with those of Wykoff (1990) for mixed conifer stands. Using independent data set, validation measures were evaluated for predicting models of diameter increment developed in this study. The result indicated that the estimated precision was all greater than 94% and the models were suitable to describe diameter increment.

Distribution of the Genetic Resource and the Biomass of Root Bark of Ulmaceae Species

  • Park, Dong Jin;Yong, Seong Hyeon;Yang, Woo Hyeong;Seol, Yuwon;Choi, Eunji;Kim, Hyeong Ho;Ahn, Mi-Jeong;Choi, Myung Suk
    • 농업생명과학연구
    • /
    • 제53권2호
    • /
    • pp.65-75
    • /
    • 2019
  • Stem and root of elm trees have used as traditional medical materials, but there is little information on the distribution and resources of habitats. Korean native growing Ulmus spp. (U. davidiana var. Japonica, U. parvifolia, U. davidiana, and U. macrocarpa) genetic resources studied through The National Forest Inventory of Korea data and field survey. The distributions of U. davidiana var. japonica according to elevation distributed evenly. Both U. parvifolia and U. davidiana were inhabited mostly at less than 200 m of altitude. Each Ulmaceae species widely were distributed nationwide, but a dominant species was different depending on locals. It observed that Ulmaceae inhabits mainly in steep slopes of 31-45 degrees. Most of the habitats regenerated by natural seeding and the most abundant species were a codominant tree. Distribution of trees in U davidiana var. japonica was 7 m-13 m, and in young U. parvifolia and U. macrocarpa, more than 25% of young trees less than 7 m observed. The distribution of the diameter of breast height of the U. davidiana var. japonica was 46.4% for 11-20 cm, 52.6% for 11-20 cm in U. parvifolia. The average T/R ratio was 0.83, and the mean weight ratio of root bark was 62%. As the results of this study, the domestic Ulmaceae biomassare very small. It is difficult to harvest in that the habitat on the slope. Thus, it is too hard to develop functional materials using biomass at present. Therefore, it is necessary to develop technology for the selection and propagation of elite trees of Ulmaceae.

18S Ribosomal DNA Sequences Provide Insight into the Phylogeny of Patellogastropod Limpets (Mollusca: Gastropoda)

  • Yoon, Sook Hee;Kim, Won
    • Molecules and Cells
    • /
    • 제23권1호
    • /
    • pp.64-71
    • /
    • 2007
  • To investigate the phylogeny of Patellogastropoda, the complete 18S rDNA sequences of nine patellogastropod limpets Cymbula canescens (Gmelin, 1791), Helcion dunkeri (Krauss, 1848), Patella rustica Linnaeus, 1758, Cellana toreuma (Reeve, 1855), Cellana nigrolineata (Reeve, 1854), Nacella magellanica Gmelin, 1791, Nipponacmea concinna (Lischke, 1870), Niveotectura pallida (Gould, 1859), and Lottia dorsuosa Gould, 1859 were determined. These sequences were then analyzed along with the published 18S rDNA sequences of 35 gastropods, one bivalve, and one chiton species. Phylogenetic trees were constructed by maximum parsimony, maximum likelihood, and Bayesian inference. The results of our 18S rDNA sequence analysis strongly support the monophyly of Patellogastropoda and the existence of three subgroups. Of these, two subgroups, the Patelloidea and Acmaeoidea, are closely related, with branching patterns that can be summarized as [(Cymbula + Helcion) + Patella] and [(Nipponacmea + Lottia) + Niveotectura]. The remaining subgroup, Nacelloidea, emerges as basal and paraphyletic, while its genus Cellana is monophyletic. Our analysis also indicates that the Patellogastropoda have a sister relationship with the order Cocculiniformia within the Gastropoda.

Molecular Phylogenetic Analyses of Three Synechococcus Strains Isolated from Seawater near the Ieodo Ocean Research Station

  • Choi, Dong-Han;Noh, Jae-Hoon
    • Ocean Science Journal
    • /
    • 제41권4호
    • /
    • pp.315-318
    • /
    • 2006
  • Three Synechococcus strains were isolated from seawater near the Ieodo Ocean Research Station (IORS), and their 16S rDNA genes and the internal transcribed spacer (ITS) between the 16S and 23S rRNA genes were sequenced to investigate their phylogenetic relationships. Phylogenetic trees based on the 16S rDNA and ITS sequences showed that they clustered in the main MC-A Synechococcus group (subcluster 5.1), but formed branches differentiating them from the described clades. As the IORS is located in an area affected by diverse water masses, high Synechococcus diversity is expected in the area. Therefore, the IORS might be a good site to study the diversity, physiology, and distribution of the Synechococcus group.

Phylogenetic study of trichaptum inferred from nuclear ribosomal DNA sequences

  • Ko, Kwon-Soo;Hong, Soon-Gyu;Jung, Hack-Sung
    • Journal of Microbiology
    • /
    • 제35권2호
    • /
    • pp.79-86
    • /
    • 1997
  • For the phylogenetic study of the genus Trichaptum, nuclear ribosomal DNA sequences from eight strains of four Trichaptium species were examined. Phylogenetic trees were constructed using molecular data on 18 rDNA and 5.8S rDNA and thei ITSs. Parsimony analyses of the Trichaptum species showed that T. biforme and T. laricinum made a monophyletic group respectively, suggesting that each species is phylogenetically independent. However, T. abietum represented a polyphyletic group and T. fusco-violaceum formed a polytomous group, suggesting that these species could be in the process of evolutionary differentiation. Examination of base substitutions of the 18S rRNA gene reveals that the C-T transition is most predominant and that there is a stronger transition bias between closely related organisms rather than between distantly related ones.

  • PDF

Molecular Phylogeny of Poecilostome Copepods Based on the 18S rDNA Sequences

  • Kim, Jihee;Kim, Won
    • Animal cells and systems
    • /
    • 제4권3호
    • /
    • pp.257-261
    • /
    • 2000
  • To elucidate phylogenetic relationships among poecilostome families 18S rDNA sequence data were generated for seven poecilostome and one cyclopoid copopods by PCR cloning and sequencing techmiques. Phylogenetic trees were constructed by maximum parsimony, neighbor joining, and maximum likelihood methods using cyclopoid sequence as an outgroup. The results from three different analyses showed that the seven poecilostome families were eiridel into two groups: Clausidiidae-Myicolidae-Synaptiphillidae-bomolochidae and Lichomologidae-Chondracanthidae-Ergasilidae. The molecular phylogenies were consistent with those from the morphological characters. Therefore, these analyses porvide further evidence for the utility of 18S rDNA sequences in addressing phylogenetic relationships among poecilostome families.

  • PDF

樹木의 胸高直經과 樹冠너비와의 關係로 본 樹冠競爭 (Crown Competition on the Relation of Crown Width to Diameter at Breast Height of Trees)

  • Park, Bong Kyu;Ok-Kyung Kim
    • The Korean Journal of Ecology
    • /
    • 제8권4호
    • /
    • pp.197-200
    • /
    • 1985
  • The relations of crown width and DBH for Pinus densiflora, Pinus rigida, Pinus koraiensis, and Ginkgo biloba were accomplished to estimate the level of crown competition. Measurements of the relations revealed that crown width and DBH were highly correlated for the same species. Also it seems that these relations are independent of age and site quality. The results of regression analysis were as follow: P. densiflora, Y=0.3477X+0.3828 r=0.95 p. rigida, Y=0.3537X+0.1645 r=0.95 P. koraiensis, Y=0.2895X+0.6310 r=0.92 G. biloba, Y=0.4360X+0.0995 r=0.90 The significant differences between G. biloba and pine species seems due to their structural differences of crown formation according to tree species. As results of computing Maximum Crown Area and Crown Competition Factor as indices of crown competition, they indicated that P. densiflora would grow better under the natural conditions.

  • PDF