• Title/Summary/Keyword: Dominant index

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Development of Site Index Equation and Curves for Site Quality Assessment of Pinus caribea Monoculture Plantations in Southwestern Nigeria

  • Oyebade, Bukola Amoo;Osho, Johnson Sunday Ajose;Adesoye, Peter Oluremi
    • Journal of Forest and Environmental Science
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    • v.30 no.4
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    • pp.315-321
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    • 2014
  • Forest timber production potential of any site is oftentimes measured quantitatively by site index, which is defined as dominant height of a particular stand at a specified age. A site index was developed for estimating site quality of monoculture Pinus caribaea plantations in southwestern Nigeria using a base age of 25 years. Dominant height data were collected from 60 Temporary Sample Plots (TSPs) of $20{\times}20m$ in plantations of 15 to 37 years. Linear and non-linear models as been widely applied in quantitative forest measurements were fitted to dominant height-age data and the best site index equation is : $SI=Exp^{(InHd-23.495(A^{-2}-0.04)}$. The site index curves constructed for the three sites (Omo Forest Reserve - OFR (J4), Oluwa Forest Reserve - OLFR and Shasha Forest Reserve - SFR) across the southwestern Nigeria using the chosen equation revealed that a 15 year old Pinus caribaea in the study area attained average dominant heights of 25, 22 and 21 m in OFR (J4), OLFR and SFR respectively. The site index equation and curves proffer veritable insight into better silvicultural options and management practices for the future plantations suitable sites.

Wetness or Warmth, Which is the Dominant Factor for Vegetation?

  • Suzuki, Rikie;Xu, Jianqing;Motoya, Ken
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.147-149
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    • 2003
  • The wetness, a function of precipitation and temperature etc, and the warmth, a function of temperature, are the dominant factor for global vegetation distribution. This paper employs the normalized difference vegetation index (NDVI), warmth index (WAI), and wetness index (WEI), and focuses on an essential climate-vegetation relationship at global scale. The NDVI was acquired from ‘Twenty-year global 4-minute AVHRR NDVI dataset.’ The WEI is defined as the fraction of the precipitation to the potential evaporation. The WAI was calculated by accumulating the monthly mean temperature of the portion exceeded 5$^{\circ}C$ throughout the year. Meteorological data for the WEI and WAI calculation were obtained from the ISLSCP CD-ROM. All analyses were conducted for 1 ${\times}$ 1 degree grid box on the terrestrial area of the Earth, and on annual value basis averaged in 1987 and 1988. The result of analyses demonstrated that there are two regimes in their relations, that is, a regime in which NDVIs vary depending on the WEI, and a regime in which NDVIs vary depending on the WAI. These two regimes appeared to correspond to the wetness dominant and warmth dominant vegetation, respectively. The geographical distributions of two regimes were mapped. Most of the world vegetation is categorized into wetness dominant, while warmth dominant vegetation is seen in the high-latitude area mainly to the north of 60$^{\circ}$N in the Northern Hemisphere and high-altitude areas.

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Ecological Attributes of Species Composition by Topographical Positions in the Natural Deciduous Forest

  • Kim, Ji-Hong;Lee, Hye-Seon;Hwang, Gwang-Mo
    • Journal of Forest and Environmental Science
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    • v.27 no.1
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    • pp.17-22
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    • 2011
  • Based upon the vegetation data of woody plants by plot sampling method in the natural deciduous forest of Mt. Jeombong, the study was carried out to examine importance value, rank abundance curve, and species abundance curve, and comparatively evaluate seven different species diversity indices for Shannon-Wiener index, Simpson index, McIntosh index, Log series, Margalef index, Berger-Parker index, and species richness, according to topographic positions. The minimal area which meant only few more species were increased was 3.48 ha in total. The dominant species of valley were Carpinus cordata, Acer pseudo-sieboldianum, Quercus mongolica, Acer mono, and Abies holophylla, and the dominant species of mid-slope were Quercus mongolica, Acer pseudo-sieboldianum, Carpinus cordata, Tilia amurensis, and Fraxinus rhynchophylla. Moreover, the dominant species of ridge were Quercus mongolica, Acer pseudo-sieboldianum, Tilia amurensis, Fraxinus rhynchophylla, and Acer mono. According to rank abundance curve and species abundance curve, species evenness was also low. All of Log series, species richness, Margalef, and Shannon-Wiener index discriminated that valley had the highest diversity, and ridge had the lowest diversity; but, Simpson index, McIntosh index, and Berger-Parker index represented that mid-slope had the highest diversity, and ridge had the lowest diversity. Uniquely, in Berger-Parker index, mid-slope was the higher value than total.

Distribution Characteristics of Fishes by a Bottom Trawl in the Jointly Controlled Waters of the East China Sea (동중국해 한일공동수역에서 저서 어획물의 분포특성)

  • Kim, Min-Seok;Kim, Dong-Su
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.3
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    • pp.330-340
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    • 2010
  • This study was investigated the species composition of demersal fishes by a bottom trawler GAYA, in order to be used basic data for resources management of fishery in the jointly controlled waters of the East China sea. We caught 52 species, 1,167 individuals and 186.171kg in biomass in summer, and 1,924 individuals and 200.871kg in biomass in winter The first dominant species in individuals in summer was Glossanodon semifasciatus, and in biomass was Dentex tumifrons. But that in winter was Ovalipes punctatus in both individuals and biomass. It was a special phenomenon that crustacea was to be the first dominant species compared with general offshore fishery in Korea. Catch per unit effort (kg/hr) of bottom trawl in winter was higher than that in summer. There was also big difference by station in the diversity index, the evenness index and the dominant index.

The Analysis of Phytoplankton Community Structure in the Middle-Lower Part of the Nakdong River (낙동강 중·하류의 식물플랑크톤 군집구조 분석)

  • Son, Hee-Jong
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.6
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    • pp.430-435
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    • 2013
  • A seasonal variation of phytoplankton community in the middle-lower part of the Nakdong River was studied in four sampling stations at monthly intervals from January to December 2012. We identified 40 genera 72 species of phytoplankton. Among these, diatoms were 36 species (50.0%), green algae 20 species (27.8%), blue-green algae 9 species (12.5%) and others 7 species (9.7%), respectively. The phytoplankton standing crops were recorded a maximum of 29,640 cells/mL at the Mulgeum (St. 4) in June and a minimum of 236 cells/mL at the Goryung (St. 1) in October. Also, Standing crops were increased with proceeding from middle part to lower part. Ecological important species were Stephanodiscus hantzschii, Cyclotella meneghiniana, Synedra acus, Aulacoseira granulata, Pediastrum sp. and Microcystis aeruginosa. Seasonal succession of phytoplankton represented that Stephanodiscus hantzschii was dominant species in winter, Cyclotella meneghiniana, Synedra acus was dominant species in spring, Microcystis aeruginosa, Cyclotella meneghiniana, Fragilaria crotonensis, Synedra acus, Aulacoseria granulata was dominant species in summer, and Aulacoseria granulata, Cyclotella meneghiniana, Fragilaria crotonensis was dominant species in autumn. In the community analysis, diversity index and dominant index were higher May~July and December~February, respectively. Also, diversity index and dominant index were decreased and increased with proceeding from middle part to lower part.

A Variation of Fishes Catched by the Bottom Trawl in the Boundary Zone between Busan and Tsushima (부산-대마도 경계수역에서 저층트롤 어획물의 변동)

  • Kim, Min-Seok;Kim, Dong-Su;Kim, Min-Son;Lee, Jong-Gun
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.3
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    • pp.341-353
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    • 2010
  • Authors investigated the species composition of fishes for about 13months in the boundary sea water between Busan and Tsushima. We caught 81 species, 1,603 individuals and 437.7kg in biomass. The first dominant species by seasons were common squid, angler, angler and Psenopsis anomala respectively. Angler was also the first dominant species in biomass for four seasons. Catch per unit effort (kg/hr) was the highest in winter and the lowest in summer. But there was a little difference in accordance with station compared with season. There was big difference by season in the diversity index, the evenness index and the dominant index. But there was little difference between above indexes. The total length of common squid was the tallest in autumn and winter, that of blackthroat seaperch was the tallest in autumn and the lowest in winter. But angler's total length was almost same all through the year.

A Study on the Ecological Characteristics and Management of Vegetation in Gudam Wetland (구담습지 식생의 생태적 특성 및 관리에 관한 연구)

  • Lee, Il Won;Kim, Kee Dae
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.133-143
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    • 2021
  • This study aims to classify the plant communities of the Gudam wetland, a riparian wetland in Nakdong River basin, and to identify the characteristics of the communities according to the veritical structure to prepare management plan. In the Gudam wetland, a total of 19 plant communities were found through physiognomical vegetation, and were analyzed by dividing into tree dominant community, shrub dominant community, and herbaceous dominant community according to the vertical structure. When examining the results of the community characteristics analysis, the species diversity index was the highest in the tree dominant communities but there was concern about a decrease in species diversity due to the influx of exotic plants such as Sicyos angulatus. The shrub dominant community tended to have a biased species diversity index on shrub plants. The herbaceous dominant communities ware divided into wetland herbaceous communities and dryland herbaceous communities according to the species diversity index, and measures were needed to reduce the species diversity index due to artificial disturbances. The importance value was the highest in the arboreal Salix genus in the tree dominant communities, and the exotic plants such as Amorpha fruticosa were the highest in the shrub dominant communities. In the herbaceous dominant communities, wetland herbaceous plants such as Phragmites japonicus were high. As a result of the analysis according to ordination the tree dominant communities and shrub dominant communities were differentiated by exotic plant factors, and the herbaceous dominant communities were differentiated by hierarchy number and slope.

B-spline Curve Approximation Based on Adaptive Selection of Dominant Points (특징점들의 적응적 선택에 근거한 B-spline 곡선근사)

  • Lee J.H.;Park H.J.
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.1
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    • pp.1-10
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    • 2006
  • This paper addresses B-spline curve approximation of a set of ordered points to a specified toterance. The important issue in this problem is to reduce the number of control points while keeping the desired accuracy in the resulting B-spline curve. In this paper we propose a new method for error-bounded B-spline curve approximation based on adaptive selection of dominant points. The method first selects from the given points initial dominant points that govern the overall shape of the point set. It then computes a knot vector using the dominant points and performs B-spline curve fitting to all the given points. If the fitted B-spline curve cannot approximate the points within the tolerance, the method selects more points as dominant points and repeats the curve fitting process. The knots are determined in each step by averaging the parameters of the dominant points. The resulting curve is a piecewise B-spline curve of order (degree+1) p with $C^{(p-2)}$ continuity at each knot. The shape index of a point set is introduced to facilitate the dominant point selection during the iterative curve fitting process. Compared with previous methods for error-bounded B-spline curve approximation, the proposed method requires much less control points to approximate the given point set with the desired shape fidelity. Some experimental results demonstrate its usefulness and quality.

Developing Dominant Tree Height Growth Curve and Site Index Curves for Pinus densiflora and Chamaecyparis obtusa Grown in Jeolla-do (전라도 지역 소나무와 편백에 대한 수고생장모델 및 지위지수곡선 개발)

  • Park, Hee-Jung;Lee, Sang-Hyun
    • Journal of Korean Society of Forest Science
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    • v.108 no.3
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    • pp.364-371
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    • 2019
  • This study was conducted to provide the basic information for a reasonable forest management plan and sustainable forest management by developing a dominant tree height growth model using diameter at breast height (DBH) and site index curves for Pinus densiflora and Chamaecyparis obtusa growing in Jeolla-do. The altitude, slope, orientation, soil type, height and DBH of a dominant tree, and the ages of trees were measured for 3055 Pinus densiflora trees (611 plots) and 3345 Chamaecyparis obtusa trees (699 plots), and these data were used to develop a customized afforestation map. In the dominant tree height growth model, the relationship to DBH was used in the Petterson, Michailow, and log equations. Also, a dominant tree height growth model in relationship to age used the Chapman-Richards, Schumacher, and Gompertz equations. The Petterson equation, which has a lower mean square error, was used to model dominant tree height growth in relationship to DBH. In the model of dominant tree height growth in relationship to age, three kinds of equations were considered to have little statistical difference. Therefore, the Chapman-Richards equation was chosen for modeling on the national level. Thirtyyears was used as the base age, which is an important factor for estimating the site index curves. In the results, a more varied range of site index family curves with 6-18 was developed for Pinus densiflora, and with 6-22 for Chamaecyparis obtusa. As the new site index curves indicated influences on growth of Pinus densiflora and Chamaecyparis obtusa, a reasonable forest management plan will be possible in the future for Jeolla-do.

The Effect of Changes in Young Women's Static Balance after Performing Walking Task with Different Carrying Bag Positions (젊은 성인 여성의 휴대 가방 위치가 보행 후 정적 균형 변화에 미치는 영향)

  • Kim, Jin-Seop;Kim, Kyoung;Jun, Deok-Hoon
    • Journal of the Korean Society of Physical Medicine
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    • v.6 no.1
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    • pp.51-58
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    • 2011
  • Purpose : This study was designed to identify the effects of carrying bag positions (None, left hand, right hand, left shoulder, right shoulder) on static balance. Methods : Fourteen healthy adult females participated in the this study. The exclusion criteria were orthopedic or neurologic disease, predominant left side. Measurements were performed initial effects. Results were evaluated by OSI, APSI, and MLSI in the biodex stability system. Results : There are among the three assessments (overall stability index(OSI), antero-posterior stability index (APSI), medio-lateral stability index(MLSI) significants difference for the carrying bags positions (None bag, left hand, right hand, left shoulder, right shoulder)(p<.05). The post-hoc test revealed a significant difference between none bag and both left hand and left shoulder in the OSI, APSI, MLSI (p<.05). Also, comparing the carrying positions significant difference between right hand and both left hand and left shoulder in the MLSI (p<.05). Conclusion : The results suggest that none dominant side with carrying bag improve more imbalance than none bag and right hand of dominant with carrying bag improve more balance than non dominant side. When comparing the four carrying bag conditions, right hand was more effective than another conditions in static balance.