• Title/Summary/Keyword: dominance value

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Tree Species Diversity and Its Population and Regeneration Status in Homegardens of Upper Assam, Northeast India

  • Saikia, P.;Khan, M.L.
    • Journal of Forest and Environmental Science
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    • v.32 no.2
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    • pp.129-139
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    • 2016
  • Study was conducted to investigate tree diversity and its population and regeneration status in homegardens of upper Assam, Northeast India through field study by quadrat method. A total of 154 tree species have been recorded from 135 studied homegardens under 109 genera 53 families. Most of these species (79%) are indigenous to our country, while the rest (21%) arealiens (naturalized and cultivated exotics) by origin. Tree species richness per homegarden varies greatly in different homegardens and is ranged from 5 to 52 tree species with a mean of 22 ($SE{\pm}0.58$). A. malaccensis is the most dominant tree species in the studied homegardens contributed 34% of the total tree density of the documented trees. The tree density is much higher with 4,259 individuals $ha^{-1}$ but, basal area ($36.32m^2ha^{-1}$) is very less. Based on the number of individuals present, very rare species is accounted for 10%, rare species 39%, common species 19%, dominants 14% and predominant species 18% in the present study. The population density of 154 tree species is 4,259 (individuals $ha^{-1}$) for adults (>3.18 cm DBH), 5,902 (individuals $ha^{-1}$) for saplings and 38,164 (individuals $ha^{-1}$) for seedlings. The density of seedlings>saplings>adults represents good regeneration status of tree species in studied homegardens. The population structure study showed that about 8% tree species have good regeneration status, 9% have fair regeneration status, 48% have poor regeneration status and 34% tree species have no regeneration. Study suggests that research and development action is needed to stimulate regeneration of those tree species which having high importance value indices but showing poor or no regeneration. Based on present observation, it can be conclude that homegarden can emerge as an effective means for both economic well-being and biodiversity conservation in upper Assam, Northeast India.

Correlation Analysis between Forest Community Structure and Environment Factor in Mt. Guryong, Gyeongsangbuk-Do Province (구룡산의 산림군집구조와 환경요인의 상관관계)

  • Lee, Seo-Hui;Kim, Hye-Jin;Yun, Chung-Weon
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.526-537
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    • 2012
  • The study was carried out to classify forest vegetation structure of Mt. Guryong which is located in Bonghwa-gun, Gyeongsangbuk-do province. 72 plots(quadrat) were investigated from July to August in 2010 using phytosociological analysis methodology of Z-M schools. The forest vegetation of the study area was classified as Quercus mongolica community group that was further divided into 5 communities; Pinus densiflora for. erecta community, Acer mono community, Quercus mongolica typical community, Larix leptolepis community and Pinus koraiensis community. Pinus densiflora for. erecta community was subdivided into Quercus variabilis group and Pinus densiflora for. erecta typical group. Acer mono community was also subdivided into Prunus maackii group and Deutzia glabrata group. The vegetation of the study areas could be described as 1 community group, 5 communities and 4 groups and 7 units in total. Classified vegetation units were highly correlated with altitude and topography. It was considered that forest tending operations for maintaining need to be continuously practiced for Quercus spp. with highly relative dominance value in the Pinus densiflora for. erecta community (vegetation units 1, 2).

SNP Detection of Carboxypeptidase E Gene and Its Association with Meat Quality and Carcass Traits in Korean Cattle

  • Shin, S.C.;Chung, E.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.328-333
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    • 2007
  • Carboxypeptidase E (CPE) plays an important role in the regulation of the body fat content. Therefore, it has been suggested as candidate gene for traits related to meat quality in beef cattle. This study was conducted to identify single nucleotide polymorphisms (SNPs) in the CPE gene and to investigate association of SNP marker with carcass and meat quality traits in Korean cattle. Three SNPs were identified in the intron 4 (A309G SNP and C445T SNP) and exon 5 (C601T SNP) of the CPE gene by sequence analyses of CPE cDNA and genomic DNA samples. The sequences have been deposited in GenBank database with accession numbers AY970664 and AY970663. Genotyping of the gene-specific SNP marker was carried out using the PCR-RFLP with restriction enzymes DdeI for C445T SNP and NlaIII for C601T SNP. The frequencies of C and T alleles were 0.43 and 0.57 for C445T SNP and 0.42 and 0.58 for C601T SNP, respectively. Statistical analysis indicated that the C445T SNP showed a significant effect (p<0.05) on marbling score (MS) and breeding value of backfat thickness (BF-EBV), respectively. Animals with the CT genotype showed higher marbling score and backfat thickness than those with the TT genotype. This marker also showed a significant dominance effect for the MS and BF-EBV (p<0.05). However, no significant associations were observed between C601T SNP genotypes and all traits examined. The results suggest that the CPE gene may be used as a marker for carcass traits in Korean cattle.

Weed Flora and Management Practices in Peach Orchard Fields in Korea

  • Jia, WeiQiang;Hwang, Ki Seon;Won, Ok Jae;Lee, In-Yong;Lee, Jeongran;Roh, Suk-Won;Park, Kee Woong
    • Weed & Turfgrass Science
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    • v.6 no.2
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    • pp.109-116
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    • 2017
  • This study was carried out two surveys in 2015 to monitor weed occurrence and determine the most troublesome weeds in peach orchards of Korea. The first survey identified 56 taxa belonging to 23 families including 27 annuals, 11 biennials, and 18 perennials. Based on importance values, Conyza canadensis (5.12%), Plantago asiatica (4.17%), and Trifolium repens (3.86%) were the dominant weeds in the first survey (from April to June). Seventeen exotic weeds were identified in the first survey, including Conyza canadensis, Trifolium repens, and Chenopodium ficifolium. The second survey (from September to October) identified 42 weeds belonging to 19 families including 23 annuals, 5 biennials, and 14 perennials. According to importance values, Digitaria ciliaris (8.00%) was the most dominant weed, followed by Echinochloa utilis (6.61%) and Rorippa palustris (6.48%). There were 12 exotic weeds, including Taraxacum officinale, Rumex crispus, and Trifolium repens. Additionally, according to Braun-Blanquet's scale showed that the dominance value was level 1 (41.98% and 46.43%, respectively) in two surveys. Currently, 40% of the total surveyed peach orchards applied herbicides for weed control. These results could provide basic data to assist orchardists in selecting the most suitable weed management methods; thereby, reducing labor inputs and effectively lowering costs while improving fruit yields in peach orchards of Korea.

Species Composition and Community Structure of Castanopsis cuspidata var. thunbergii Communities (모밀잣밤나무군락의 종 조성 및 군락구조)

  • Jung, Hye-Ran;Jeon, Kwon-Seok;Kim, Jong-Kab;Moon, Hyun-Shik
    • Korean Journal of Environmental Agriculture
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    • v.27 no.4
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    • pp.421-427
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    • 2008
  • This study was carried out to offer a basis data for application of effective management through species composition and community structure of Castanopsis cuspidata var. thunbergii stands (Bijindo and Yokjido). The upper, middle and lower layer in Bijindo and Yokjido consisted of 10, 11 and 27 species, and 9, 6 and 28 species, respectively. The importance value of Castanopsis cuspidata var. thunbergii were highest in upper and middle layer both two studied site. The herbaceous species were 33 and 47 species in Bijindo and Yokjido, respectively. The species diversity ranged from 0.523 to 1.280 in Bijindo and 0.699 to 1.364 in Yokjido. Dominance in Bijindo and Yokjido were 0.477 and 0.242 at upper layer, 0.231 and 0.102 at middle layer, and 0.106 and 0.057 at lower layer, which showed that Castanopsis cuspidata var. thunbergii stands are dominated by a large number of species at all layer. The distribution pattern by Morisita's index showed that Castanopsis cuspidata var. thunbergii was distributed randomly in upper layer both the studied sites.

GIS application on weed control of Eleocharis kuroguwai in lowland rice field in Korea (GIS를 이용한 논 잡초 올방개의 방제연구)

  • ;;S.P.Kam
    • Spatial Information Research
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    • v.3 no.1
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    • pp.47-53
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    • 1995
  • The weed survey in lowland rice fields through Korea was conducted in 1992 to determine a change of the weed communities based on different regions, soil types, planting methods, and cultural practices. GIS was applied to identify a spatial analysis of predominant weed species in specific region. On behalf of vegetatine analysis such as absolute and relative density, absolute and relative frequency, importance value, and summed dominance ratio(SDR), there was highly dominant with a perennial weed species, Eleocharis kuroguwai Ohwi over whole country. However, in particular it was most predominant at southem area of Gyunggi province in Korea. Thus, rice farmers of this area have to introduce a specific comperhensive control strategy against this predominant weed species.

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Syntaxonomy and Soil Condition of Mt. Nam nature park (남산자연공원의 식물군락분류와 토양환경)

  • 이호준;전영문;정흥락;길지현;홍문표;김용옥;장일도
    • The Korean Journal of Ecology
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    • v.21 no.5_3
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    • pp.633-648
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    • 1998
  • The forest vegetation of Mt. Nam Nature Park was investigated according to the phytosociological method. The vegetation in this study area was classified into 5 communities Quercus mongolica (Acer pseudo-sieboldianum subcommunity, Prunus sargentii subcommunity), P. sargentii, Pinus densiflora (Q. mongolica subcommunity, Stephanandra incisa subcommunity) and 5 afforestations Robinia pseudo-acacia, Populus tomentoglandulosa, P. koraiensis, P. rigida, Metasequoia glyptostroboides. Generally, were P. densiflora forest at the Southern slope and Q. mongolica forest at Northern slope dominant species from the top zone standing in Namsan tower. The dominance sequences on each stratum determined by the R-NCD (Relative net Contribution Degree) showed Q. mongolica and P. densiflora in tree-1 layer, Styrax japonica and Corbus alnifolia in tree-2 layer, S. incisa, S. japonica and rhododendron schlipenbachii in shrub layer, and Oplismenus undulatifolius, Eupatorium rugosum, Parthenocissus tricuspidata and Disporum smilacinum in herb layer. The soil was analyzed to investigate the soil conditions and fertility. The pHs of soil collected in each sites appeared strongly acidic with the range of 4.34 to 5.01 each community and especially, was the lowest value 4.34 in P. rigida afforestation. And Q. mongolica-P. sargentii subcommunity was distributed at the area with relative mesic conditions and high organic matters. Nitrogen was highest at P. sargentii community, phosphate at P. densiflora-S. incisa subcommunity, calcium, potasium and magnesium of exchangeble cation at R. pseudo-acacia afforestation. Especially, the level of calcium in R. pseudo-acacia afforestation, P. koraiensis afforestation and P. densiflora community was shown the highest (0.38-1.48 mg/100g) compared to other communities, because of the influence of lime fertilization used to improve acidic soil.

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Ecological Characteristics of Sub-Alpine Coniferous Forest on Banyabong in Mt. Jiri (지리산 반야봉 아고산 침엽수림의 생태적 특성)

  • Cho, Min-Gi;Chung, Jae-Min;Im, Hyo-In;Noh, Il;Kim, Tae-Woon;Kim, Chung-Yeol;Moon, Hyun-Shik
    • Journal of Climate Change Research
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    • v.7 no.4
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    • pp.465-476
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    • 2016
  • This study was conducted to elucidate the ecological characteristics of sub-alpine coniferous forest on Banyabong, Mt. Jiri. Soil pH was 4.20. The contents of organic matter, total N, available P and CEC were 14.15%, 0.43%, 10.1 ppm and $17.17cmol^+/kg$, respectively. Sub-alpine coniferous forest had a relatively soil moisture content with 22.9%. According to the results of importance value analysis, Picea jezoensis (42.7) and Abies koreana (34.0) for tree layer, Rhododendron schlippenbachii (25.5) for subtree layer and Tripterygium regelii (18.4) and Rhododendron mucronulatum (16.6) for shrub layer were high, respectively. Shannon's diversity ranged from 0.3560 to 1.050. Evenness and dominance ranged from 0.398 to 0.733 and 0.267 to 0.601, respectively. A. koreana population had a reverse J-shaped DBH distribution, while P. jezoensis population had a normal DBH distribution. Height growth according to DBH of A. koreana was higher than that of P. jezoensis, which indicate than A. koreana have more effective water use efficiency than P. jezoensis. Annual mean tree ring growth of P. jezoensis and A. koreana showed up 1.792, 1.652, 1.389 mm/yr and 2.081, 1.921, 1.576 mm/yr for small, middle and large diameter tree, respectively.

The Ecological Characteristics by Slope of an Abies koreana Forest in Seseok of Jirisan National Park (지리산 세석 구상나무림의 사면별 생태적 특성)

  • Noh, Il;Chung, Jae-Min;Kim, Tae-Woon;Tamirat, Solomon;Moon, Hyun-Shik
    • Journal of Climate Change Research
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    • v.9 no.3
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    • pp.293-302
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    • 2018
  • This study was carried out to provide basic information on efficient preservation and management of an Abies koreana forest through analyzing the ecological characteristics by slope in Seseok, Mt. Jirisan. Soil moisture content at southern and northern slopes was 29.9% and 21.7%, respectively, and there was no significant difference among soil properties between southern and northern slopes. The importance value of A. koreana in the southern and northern slopes was high for tree and subtree layers, respectively. It is noteworthy that many seedling and saplings of A. koreana were present on the southern slope. The species diversity was 0.413 for the tree layer, 0.632 for the subtree layer, and 0.609 for the shrub layer on the southern slope and 0.396 for the tree layer, 0.783 for the subtree layer, and 1.215 for the shrub layer on the northern slope. Evenness and dominance ranged from 0.371 to 0.609 and 0.629 to 0.391 on the southern slope and from 0.380 to 0.968 and 0.620 to 0.032 on the northern slope, respectively. The mortality of A. koreana was 9.6% on the southern slope and 24.4% on the northern slope, a distinct difference between the slopes. The mortality type at two slopes was the highest proportion of standing dead. Annual mean tree ring growth of A. koreana on the southern slope (1.76 mm/yr) was higher than that on the northern slope (1.64 mm/yr).

Diversity and Composition of Tree Species in Madhupur National Park, Tangail, Bangladesh

  • Rahman, Md. Rayhanur;Hossain, Mohammed Kamal;Hossain, Md. Akhter
    • Journal of Forest and Environmental Science
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    • v.35 no.3
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    • pp.159-172
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    • 2019
  • Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.