• Title/Summary/Keyword: Geographic variation

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Overview of Research Trends in Estimation of Forest Carbon Stocks Based on Remote Sensing and GIS (원격탐사와 GIS 기반의 산림탄소저장량 추정에 관한 주요국 연구동향 개관)

  • Kim, Kyoung-Min;Lee, Jung-Bin;Kim, Eun-Sook;Park, Hyun-Ju;Roh, Young-Hee;Lee, Seung-Ho;Park, Key-Ho;Shin, Hyu-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.3
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    • pp.236-256
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    • 2011
  • Forest carbon stocks change due to land use change is an important data required by UNFCCC(United Nations framework convention on climate change). Spatially explicit estimation of forest carbon stocks based on IPCC GPG(intergovernmental panel on climate change good practice guidance) tier 3 gives high reliability. But a current estimation which was aggregated from NFI data doesn't have detail forest carbon stocks by polygon or cell. In order to improve an estimation remote sensing and GIS have been used especially in Europe and North America. We divided research trends in main countries into 4 categories such as remote sensing, GIS, geostatistics and environmental modeling considering spatial heterogeneity. The easiest way to apply is combination NFI data with forest type map based on GIS. Considering especially complicated forest structure of Korea, geostatistics is useful to estimate local variation of forest carbon. In addition, fine scale image is good for verification of forest carbon stocks and determination of CDM site. Related domestic researches are still on initial status and forest carbon stocks are mainly estimated using k-nearest neighbor(k-NN). In order to select suitable method for forest in Korea, an applicability of diverse spatial data and algorithm must be considered. Also the comparison between methods is required.

Geographic Variations and DNA Polymorphisms in Gizzard-shad (Konosirus punctatus) (전어 (Konosirus punctatus)의 지리적 변이와 DNA 다형성)

  • Park, Su-Young;Kim, Jong-Yeon;Yoon, Jong-Man
    • Korean Journal of Ichthyology
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    • v.18 no.4
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    • pp.300-310
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    • 2006
  • Genomic DNA isolated from three geographical gizzard-shad (Konosirus punctatus) populations in Seocheon (SC), Busan (BS) and Gochang (GC) collected in the West Sea and the southern sea, respectively, off the Korean Peninsula, were PCR-amplified repeatedly. Eight selected decamer and 20-mer primers generated a total of 713 loci in the SC population, 791 in the BS population, and 732 in the GC population, with a DNA fragment size ranging from 100 bp to 2,800 bp. We identified 50 unique loci for the SC population, 70 unique loci for the BS population and 130 for the GC population: 120 shared loci for the three populations. There were 108 specific loci (15.1%) for the SC population, 74 (9.4%) for the BS population, and 67 (9.2%) for the GC population. Eight primers also generated 48 polymorphic loci (6.7%) for the SC population, 26 (3.3%) for the BS population, and 16 (2.2%) for the GC population. The similarity matrix ranged from 0.756 to 0.936 for the SC population, from 0.800 to 0.938 for the BS population, and from 0.731 to 0.959 for the GC population. The dendrogram obtained by the eight primers indicates three genetic clusters: cluster 1 (SEOCHEON 01~SEOCHEON 10), cluster 2 (BUSAN 11~BUSAN 20 and GOCHANG 23~GOCHANG 24), and cluster 3 (GOCHANG 21, 22, 25, 26, 27, 28, 29 and 30). As stated above, some individuals of the GC population appear to belong in BS population. When seeing this result, it was thought with the fact that some individuals of 2 populations seem to come and go partially. Thus, RAPD-PCR analysis revealed a significant genetic distance between the three geographical gizzard-shad populations. Using various decamer and 20-mer primers, RAPD-PCR may be applied to identify specific/polymorphic markers that are particular to a species and geographic population, and to define genetic diversity, polymorphisms, and similarities among geographical gizzard-shad populations.

A Study on the Variation of River Vegetation by Seasonal Precipitation Patterns (계절별 강수 패턴에 따른 하천 식생 변화 양상 연구)

  • Hee-Jeong JEONG;Seung-Yeon YU;Eun-Ji CHO;Yong-Joo JI;Yong-Suk KIM;Hyun-Kyung OH;Jong-Sung LEE;Hyun-Do JANG;Dong-Gil CHO
    • Journal of the Korean Association of Geographic Information Studies
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    • v.26 no.2
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    • pp.1-19
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    • 2023
  • In Korea, excessive vegetation in rivers made up of sand and gravel is emerging as a nationwide problem, which is attributed to increased spring precipitation and decreased annual precipitation. Therefore, this study was conducted for the purpose of identifying the effect of changes in precipitation patterns on river vegetation in Namcheon, Gyeongju, and analyzing the area of vegetation and ecological characteristics. As a result of the study, the amount of monthly precipitation in the summer of Namcheon decreased after 2007, and the area of vegetation increased continuously compared to the area of the sandbank. The proportion of naturalized plants increased steadily when precipitation continued to a level that did not cause flooding, but the area occupied by naturalized plants was small. Also, when the water level is maintained, the species diversity is low due to the dominance of a single species, and the dominant species was mainly native plants. Dominance of native plants inhibited the growth of naturalized plants, but the vegetation area increased even more. Therefore, it is necessary to manage the spread of vegetation itself rather than the division of native plants and naturalized plants in order to eliminate the active growth and prosperity of river vegetation. High water levels and continuous flooding caused by torrential rains in summer disturbed the plant communities, and vegetation formed afterwards was mainly native plants. Such flooding in river ecosystems is a positive factor for the emergence of native plants and over-formed vegetation communities, so it should be considered when establishing a vegetation management plan.

An Analysis of Morphological Variation in Abies koreana Wilson and A. nephrolepis (Traut.) Maxim. of Korea (Pinaceae) and Their Phylogenetic Problems (한국산(韓國産) 분비나무와 구상나무의 형질분석(形質分析)과 종간유연관계(種間類緣關係))

  • Chang, Chin-Sung;Jeon, Jeong Ill;Hyun, Jung Oh
    • Journal of Korean Society of Forest Science
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    • v.86 no.3
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    • pp.378-390
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    • 1997
  • Ten total populations of Korean fir (Abies koreana Wilson) and Manshurian fir [A. nephrolepis (Traut.) Maxim.] were sampled from south Korea to investigate patterns of intraspecific variation in these species and to evaluate a recognition of the two species. Principal components analysis and cluster analysis were performed both on seed-cone data and on needle morphology data. The characters that contributed most to the separation between A. koreana and A. nephrolepis along three principal components axis were leaf width, length of seed, width of seed wing, length of seed wing, cone width, width of scale, and length of bract tip, but these characters were not diagnostic because of overlap in reality. Therefore, all these characters were not reliable in distinguishing these two taxa including bract position (exerted and recurved vs. exerted and straight). The individuals of A. koreana from Mt. Chi-ri appeared quite unique probably on account of its larger cone size and longer scale tip, while those from Mt. Hal-la of A. koreana were generally distinct from others in terms of their larger seed and seed wing and longer scale width. The Mt. Duk-yu specimens of A. korecana appeared somewhat smaller but more data were needed due to the small sampling size. Generally, the gradual clinal geographic trends made evident by the position of resin ducts in leaves of A. koreana can be detected. The southern populations, Mt. Hal-la (an insular population) were generally distinct from the northern populations (Mt. Chi-ri, Mt. Ga-ya and Mt. Duk-yu) in terms of their position of resin duct (medial, within mesophyll vs marginal, close to epidermis : 100% vs 75 or 50%). Although no sharp boundary separating these two species could be detected based on cone and needle morphology, the observed clinal pattern was distinct in northern populations of A. koreana and southern population of A. nephrnlepis. In a preceding study of the flavonoids variation of 20 species in eastern Asia, flavanone (5-deoxyflavanone) was found to be characteristic of A. faxoniana Rehder et Wilson, A. georgei Orr of China and A. koreana of Korea. A. faxoniana, which is assumed to be primitive species, has position of resin duct relative to both the medial and the marginal, while A. georgei and A. koreana are identified by marginal position of resin duct. With respect of foliar flavonoids chemistry, A. koreana was distinct from A. nephrolepis : the southmost samples (Mt. Hal-la and Mt. Chi-ri) contained additional flavonoids derivatives (mainly flavanone) that were not found in the northmost samples of A. nephrolepis except a few individuals from Mts. Seo-rak and Tae-bak populations of Kwang-won province. The presence of A. koreana type flavonoids in two Chinese species suggested that position of resin duct may be a phyletic character. Abies koreana including two Chinese taxa, exhibited the most elaborate and specialized flavonoids profile within the Abies in eastern Asia. Contrary to our initial expectations, the apparent intermediates between A. nephrolepis and A. koreana in Duk-yu and Ga-ya mountains were found. The pattern of variation on position of resin duct and flavonoids chemistry in these populations of A. kareana suggested that genetic interchange or natural hybridization had occurred between these two species. The evidence needed to resolve the status of this taxon is still inconclusive in our opinion until intermediate individuals from Mts. Duk-yu and Ga-ya show indication of hybridization between the two species.

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Genetic Diversity and Structure of the Korean Endemic Species, Coreanomecon hylomeconoides Nakai, as Revealed by ISSR markers (한국 특산식물 매미꽃(Coreanomecon hylomeconoides Nakai) 집단의 유전다양성 및 구조)

  • Son, Sung-Won;Chung, Jae-Min;Kim, Eun-Hye;Choi, Kyoung-Su;Park, SeonJoo
    • Korean Journal of Plant Resources
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    • v.26 no.2
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    • pp.310-319
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    • 2013
  • The genetic diversity and structure of eight populations of Coreanomecon hylomeconoides Nakai, an endemic Korean plant, were investigated using 50 ISSR loci from eight primers. The average percentage of polymorphic loci was 47.3%. The Shannon's index (SI=0.218) and gene diversity (h=0.142) were relatively lower than those of other long-lived perennials. The Sancheong (SI=0.233, h=0153), Gwangyang (SI=0.263, h=0.171), and Suncheon (SI=0.241, h=0.159) populations showed greater genetic diversity than the Namhae and Gwangju populations, which are on the edge of the distribution. Analysis of molecular variance (AMOVA) showed that 18% of the total variation could be attributed to differences among populations, and 82% to differences within populations, indicating moderate gene flow among adjacent populations. These results were supported by value of Nm (2.184). The UPGMA conducted using the genetic distance and Bayesian cluster analysis showed a remarkable geographic trend structured into east and west regions. Overall, the results indicate that the Sancheong and Gwangyang populations, which had a large population size and higher degree of genetic diversity, should be the focus of in situ conservation.

Genetic Diversity and Population Structure of Codium fragile (SURINGAR) HARlOT in Korea Using Allozymes (알로자임을 이용한 청각의 유전적 다양성과 집단구조)

  • Lee Bok-Kyu;Park So-Hye;Heo Youn-Seong;Ju Mu-Teol;Choi Joo-Soo;Huh Man-Kyu
    • Journal of Life Science
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    • v.16 no.2 s.75
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    • pp.213-218
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    • 2006
  • The study of genetic diversity and population structure was carried out in the Codium fragile using allozyme analysis. Although this species has been regarded as a ecologically and economically important source, there is no report on population structure in Korea. Starch gel electrophoresis was used to investigate the allozyme variation and genetic structure of four Korean populations of this species. Of the 15 genetic loci surveyed, nine (60.0%) was polymorphic in at least one population. Genetic diversity was high at the species level ($H_{ES}$=0.144), and, that of the population level was relatively low ($H_{EP}$=0.128). Nearly 87% of the total genetic diversity in C. fragile was apportioned within populations. The predominant asexual reproduction, population fragmentation, low fecundity, geographic isolation and colonization process are proposed as possible factors contributing to low genetic diversity in this species. The indirect estimated of gene flow based on $G_{ST}$ was 1.69. The moderate level of gene flow in C. fragile populations is mainly caused by thallus developed from isolated utricles dispersal via sea current.

Observations on the Genetic Structure of Pinus densiflora Sieb. et Zucc(I) : The Young-il Population (소나무의 유전적(遺傳的) 구조(構造)에 관한 연구(硏究) (I) : 영일(迎日) 집단(集團)의 유전적(遺傳的) 구조(構造))

  • Chung, Min Sup
    • Journal of Korean Society of Forest Science
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    • v.80 no.2
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    • pp.246-254
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    • 1991
  • Genetic structure of a Pinus densiflora population consisting of two subpopulations on the north-and south-facing slopes of a mountain was studied by allozyme analysis. Allozyme variants in aspartate aminotransferase(AAT), glutmate dehydrogenase(GDH) and leucine aminopeptidase(LAP) systems are encoded, at least, by eight loci ; five for AAT, one for GDH and two for LAP. Average number of alleles examined over six loci was 3.33. Average heterozygosity and genetic diversity computed over six loci were, respectively, 0.19 and 2.76 for parental population, 0.17 and 2.22 for progeny population. Differences in allelic frequencies between maternal sources at many of the investigated loci were found and between subpopulations on the north- and south-facing slopes. Allele frequencies of maternal origin at some of the loci were significantly different from each other between the two subpopulations. Thus it appears that the matings within and between subpopulations were not random and the mountain ridge that divides the north-and south-facing slopes isolate the two suhpopulations reproductively to a great extent. Some of the genotypes both in parental and progeny(embryo) groups deviate significantly from the Hardy-Weinberg equilibrium state. It appears from the result that the pine population is originated from a few limited ancestral trees and thus consanguineous matings are prevalent in this pine population.

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Morphometric Analyses of Damaster(Coptolabrus) jankowskii from Korea(Coleoptera : Carabidae) (한국산(韓國産) 멋쟁이딱정벌레의 계량형태학적(計量形態學的) 분석(分析) (초시목(鞘翅目) : 딱정벌레과(科)))

  • Kwon, Yong Jung;Park, Jong Kyun
    • Current Research on Agriculture and Life Sciences
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    • v.7
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    • pp.127-151
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    • 1989
  • The ground beetles or carabids are essentially predaceous feeding on a wide variety of insects including forest pests, slugs and land snails containing those injurious to livestock or veterinary, thus many are predominantly beneficial and serve as natural enemies. In the present investigation, some morphometric multivariate analysis were done for 9 different populations in 5 subspecies of D. (C.) jankowskii, which are one of the most common ground beetles in Korea As the results, when the comparison was conducted between intraspecific groups regardless of subspecies in external morphological characters, the average group membership revealed 97.46% correct assignment For intersubspecific comparisons alone 96.3% were correctly classified. Between the groups of ssp. jankowskii an average of 100% individuals were classified in their known group. Thus the predict group membership was highly significant(P<0.001), exceeding so-called 'the 75% rule'. Whereas, the average group membership using the male genitalic characters represented less than the 75% assignment, except only in ssp. quelpartianus (85.6%). The population from Is. Chindo were described here as a new subspecies for qualitative as well as the resultant quantitative differences. Therefore, a total of 7 subspecies are represented in Korea. Among them, the nominate subspecies, ssp. jankowskii(sensu lato), revealed distinct intrasubspecific differences between different geographic populations. These differences can be as notable as intersubspecific variation which need substantial revision of the previous intuitional concepts on the infraspecific level.

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Effects of Areal Interpolation Methods on Environmental Equity Analysis (면내삽법이 환경적 형평성 분석에 미치는 영향)

  • Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
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    • v.14 no.6
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    • pp.736-751
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    • 2008
  • Although a growing number of studies have commonly used a simple areal weighting interpolation method to quantify demographic characteristics of impacted areas in environmental equity analysis, the results obtained are inevitably imprecise because of the method's unrealistic assumption that population is evenly distributed within a census enumeration unit. Two alternative areal interpolation methods such as intelligent areal weighting and regression methods can account for the distributional biases in the estimation of impacted populations by making use of additional information about the geographic distribution of population. This research explores five areal interpolation methods for estimating the population characteristics of impacted areas in environmental equity analysis and evaluates the sensitivity of the outcomes of environmental equity analysis to areal interpolation methods. This study used GIS techniques to allow areal interpolation to be informed by the distribution of land cover types, as inferred from a satellite image. in both the source and target units. Independent samples t-test statistics were measured to verify the environmental equity hypothesis while coefficients of variation were calculated to compare the relative variability and consistency in the socioeconomic characteristics of populations at risk over different areal interpolation methods. Results show that the outcomes of environmental equity analysis in the study area are not sensitive to the areal interpolation methods used in estimating affected populations, but the population estimates within the impacted areas are largely variable as different areal interpolation methods are used. This implies that the use of different areal interpolation methods may to some degree alter the statistical results of environmental equity analysis.

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Systematic Study on the Aconitum alboviolaceum Complex (Ranunculaceae) in Korea (한국산 줄바꽃 종집단의 분류학적 연구)

  • Lee, Soo-Rang;Park, Chong-Wook
    • Korean Journal of Plant Taxonomy
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    • v.37 no.4
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    • pp.477-502
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    • 2007
  • The Aconitum alboviolaceum Kom. complex includes four controversial species described from Korea; A. albouiolaceum, A. pseudolaeue, A. longecassidatum, and A. quelpaertense. The main objective of this study was to determine the taxonomic identities and systematic relationships among the species in the A. albouiolaceum complex based on morphology, numerical analyses and DNA sequence analysis. In the present study, variations in the principal morphological characters and chloroplast DNA noncoding region sequences (psbA-trnH IGS, trnL intron, and trnL-trnF IGS) were examined for 95 individuals from 20 populations. Also, neighbor-joining analysis was adopted to infer their relationships. Morphological variation appeared to be considerably high but not to be related to geographic distribution. These morphological results suggest that reevaluation of key morphological characters are needed for the proper taxonomic treatment of the complex. The length of psbA-trnH IGS region ranged from 241 to 250 bp, that of the trnL intron from 526 to 532 bp, and that of the trnL-trnF IGS region from 466 to 472 by in all taxa. Nine haplotypes were recognized from the analysis. Seven populations shared more than two haplotypes, while other thirteen populations shared only one haplotype. In the phylogenetic analysis, the nine haplotypes formed four groups, separated A. sibiricum, one of the sister groups of the complex. There also was no distinct grouping pattern supporting the species and populations observed. These results suggest that introgression or speciation might have been involved in the formation of taxa of A. alboviolaceum complex.