• Title/Summary/Keyword: slope (north, south)

Search Result 125, Processing Time 0.026 seconds

Estimation of R-factor for Universal Soil Loss Equation with Monthly Precipitation Data in North Korea (북한 지역의 월 강수량으로부터 토양 유실 예측 공식 적용을 위한 강수 인자 산출)

  • Jeong, Yeong-Sang;Park, Cheol-Soo;Jeong, Pil-Kyun;Im, Jung-Nam;Shin, Jae-Sung
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.35 no.2
    • /
    • pp.87-92
    • /
    • 2002
  • Soil erosion is detrimental to sustain soil productivity in north Korea, since agriculture of this country depends largely upon the slope land in mountainous area. Taking any measure for protection from erosion should be based on prediction of soil loss. Estimation of rainfall factor, R, in north Korea for the Universal Soil Loss Equation was attempted. The monthly precipitation data of the twenty six locations provided by the Korean Meteorological Adminstration were used. From the relationship between II_30 and the July-August precipitation concentration percents, the regional adjustment factor was obtained. The rainfall factor was calculated with the monthly precipitation data and the regional adjustment factor. The annual precipitation in north Korea ranged from 606 to 1,520mm, and the July-August precipitation concentration percents were 34.4 to 53.8. The regional adjustment factor ranged from 0.53 to 1.33 showing lower value in the highland and east coastal region than in the mid mountainous inland and west region. The R-factor value estimated from the monthly precipitation and the regional adjustment factor ranged from 107 to 483, which was lower than average value in south Korea.

Environmental Characteristics and Species Composition of Boehmeria platanifolia Habitat in South Korea (남한 개모시풀의 자생지 환경특성과 혼생식물종 분포)

  • Kim, Seong-Min;Shin, Dong-Il;Song, Hong-Seon;Yoon, Seong-Tak;Cho, Yong-Koo
    • Korean Journal of Medicinal Crop Science
    • /
    • v.16 no.5
    • /
    • pp.371-375
    • /
    • 2008
  • This study was conducted to evaluate geographical distribution patterns of natural habitats, soil properties, and plant species grown with native Boehmeria platanifolia in South Korea. The relative density and coverage of Boehmeria platanifolia were 7.0% and 25.6% respectively. Most Boehmeria platanifolia were growing below 200 m of altitude, and they were rarely found at the higher altitude. Over 80% of Boehmeria platanifolia's habitats were found at below $20^{\circ}$ and their habitats were concentrated at the west and the north face slope rather than the south face slope. Nearly 90% of Boehmeria platanifolia were grown at little and middle light condition's area, and 69.1% of them were natively growing in humid soil in their natural habitats. Soil texture of their habitats were mostly clay loam and the soil pH was 6.2. The contents of soil organic matter was $24\;g\;kg^{?1}$ and $P_2O_5$ was $31\;mg\;kg^{?1}$. Plant species grown with native Boehmeria platanifolia were 60 family, 125 genus and 171 species. Clematis apiifolia showed the highest relative density and coverage among plant species grown with native Boehmeria platanifolia.

Geographical distribution range and growth environmental characteristics of Deutzia paniculata Nakai, a Korean Endemic Plant (한반도 특산식물 꼬리말발도리의 분포와 생육환경특성)

  • Jung, Ji-young;An, Jong-Bin;Yun, Ho-Geun;Jung, Su-Young;Shin, Hyun-Tak;Son, Sung-won
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.23 no.2
    • /
    • pp.1-16
    • /
    • 2020
  • The current status of geographical distribution range of Deutzia paniculata, one of the korean endemic plants, was investigated based on the species distribution information. The information of the geographical range used for analysis includes all the published references to the distribution of D. paniculata, herbarium specimens in Korea National Arboretum (KH) including its online database: http://www.nature.go.kr, and field research. Although, D. paniculata was firstly recorded in Wonsan, Hamgyeongnam-do, North Korea, this research revelaved that D. paniculata is mainly distributed in Gyeongsangbuk-do and Gyeongsangnam-do, southern regions of the Korean Peninsula. According to the distribution map, this species was estimated on distribution edge of in Anyang region of Gyeonggi-do, Mt. Naejang of Jeollabuk-do and Mt. Taebaek of Gwangwon-do on the distribution edge. However, it was made use of intensive field survey to identify the natural population of the species in these regions. D. paniculata habitat was mainly distributed between 290 meters and 491 meters in altitude, but it was also found ranged from 936 to 959 meters in Gun-wi, Gyeongsangbuk-do, South Korea. The distribution slope was 5° to 35° and the north, N, NE and NW in the aspect. The flora of vascular plants in D. paniculata habitats was listed in 137 taxa: 54 families, 103 genera, 120 species, 2 subspecies, 12 varieties and 3 forms while Korean endemic plants were found in three taxa, Stewartia koreana, Weigela subsessilis and D. Paniculata. Based on a collection of non-biological environment and biological environment data, D. paniculata population were discussed to make strategy and basic research methods for sustainable preservation.

Forest Vegetation of the Jangtaesan, Haetaesan, Ahnpyoungsan and Gubongsan area in Daejeon Metropolitan City, Korea (대전 장태산, 해태산, 안평산과 구봉산 지역의 산림식생)

  • Kim, Hyo-Jeong;Lee, Mi-Jeong;Kwon, Oh-Won;Shin, Dong-Hoon;Lee, Kyoo-Seok;Seo, Byung-Key;Song, Ho-Kyung
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.7 no.5
    • /
    • pp.47-56
    • /
    • 2004
  • This study was carried out to analyze forest vegetation of the Jangtaesan, Haetaesan, Ahnpyoungsan and Gubongsan in Daejeon. Employing the releve method of Braun-Blanquet, 76 plots were sampled. The communities were classified into Quercus mongolica community, Quercus variabilis community, and Pinus densiflora community. Average coverage rate was 85% in tree layer, 44% in subtree layer, 37% in shrub layer, 25% in herb layer, respectively. The importance values were 58.76 in Pinus densiftora, 44.86 in Quercus monegolica, 44.06 in Quercus variabilis, 33.00 in Quercus serrata, 18.73 in Rhus trichocarpa, 18.07 in Prunus sargentii. DBH range of most Pinus densiflora, Quercus mongolica and Quercus variabilis was between 5cm and 20cm. Therefore, Pinus densiflora, Quercus mongolica and Quercus variabilis will be dominant species in the study area for several more decades. Quercus mongolica community was distributed mainly on the north and east slope in a high-altitude and relative good nutrition condition. Querucus variabilis community was distributed mainly on the south slope in a middle-altitude and medium nutrition condition. Pinus densiflora community was distributed mainly in a low-altitude and poor nutrition condition.

Evaluating Applicability of SRTM DEM (Shuttle Radar Topography Mission Digital Elevation Model) in Hydrologic Analysis: A Case Study of Geum River and Daedong River Areas (수문인자추출에서의 SRTM DEM (Shuttle Radar Topography Mission Digital Elevation Model) 적용성 평가: 대동강 및 금강 지역 사례연구)

  • Her, Younggu;Yoo, Seung-Hwan
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.6
    • /
    • pp.101-112
    • /
    • 2013
  • Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) offers opportunities to make advances in many research areas including hydrology by providing near-global scale elevation measurements at a uniform resolution. Its wide coverage and complimentary online access especially benefits researchers requiring topographic information of hard-to-access areas. However, SRTM DEM also contains inherent errors, which are subject to propagation with its manipulation into analysis outputs. Sensitivity of hydrologic analysis to the errors has not been fully understood yet. This study investigated their impact on estimation of hydrologic derivatives such as slope, stream network, and watershed boundary using Monte Carlo simulation and spatial moving average techniques. Different amount of the errors and their spatial auto-correlation structure were considered in the study. Two sub-watersheds of Geum and Deadong River areas located in South and North Korea, respectively, were selected as the study areas. The results demonstrated that the spatial presentations of stream networks and watershed boundaries and their length and area estimations could be greatly affected by the SRTM DEM errors, in particular relatively flat areas. In the Deadong River area, artifacts of the SRTM DEM created sinks even after the filling process and then closed drainage basin and short stream lines, which are not the case in the reality. These findings provided an evidence that SRTM DEM alone may not enough to accurately figure out the hydrologic feature of a watershed, suggesting need of local knowledge and complementary data.

Genetic Structure of Pinus rigida Mill. in an Expanding Population Originating from a Few Founder Trees (수본(數本)의 양친수(兩親樹)에 의해 전파증식(傳播増殖)중에 있는 리기다소나무 집단(集團)의 유전적(遺傳的) 구조(構造))

  • Chung, Min Sup
    • Journal of Korean Society of Forest Science
    • /
    • v.72 no.1
    • /
    • pp.16-26
    • /
    • 1986
  • Allozyme study on a small pitch pine stand originating and expanded rather rapidly from a few founder trees indicated that the colonization of the pitch pine population was made progressively from the place where the founder trees located to another by moving in cohorts of seeds from a limited number of family or genetically closely related family groups in line with the succeeding generations. This pattern of migration and colonization resulted marked differences in allelic and genotypic frequencies at many of the allozyme loci between the initially colonized subpopulation on the south-facing slope and the lately colonized subpopulation on north-facing slope of a hill. It appeared that gene fixation due to inbreeding and genetic drift occurred at some loci in the pitch pine population or subpopulations. However, even in t 1e inbreeding small pitch pine population or subpopulations, a comparatively large amount of genetic diversity or heterozygosity was maintained due to the high levels of gene recombination at many of the gene loci and natural selections favoring for heterozygotes.

  • PDF

Spatial Characteristics and Driving Forces of Cultivated Land Changes by Coupling Spatial Autocorrelation Model and Spatial-temporal Big Data

  • Hua, Wang;Yuxin, Zhu;Mengyu, Wang;Jiqiang, Niu;Xueye, Chen;Yang, Zhang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.15 no.2
    • /
    • pp.767-785
    • /
    • 2021
  • With the rapid development of information technology, it is now possible to analyze the spatial patterns of cultivated land and its evolution by combining GIS, geostatistical analysis models and spatiotemporal big data for the dynamic monitoring and management of cultivated land resources. The spatial pattern of cultivated land and its evolutionary patterns in Luoyang City, China from 2009 to 2019 were analyzed using spatial autocorrelation and spatial autoregressive models on the basis of GIS technology. It was found that: (1) the area of cultivated land in Luoyang decreased then increased between 2009 and 2019, with an overall increase of 0.43% in 2019 compared to 2009, with cultivated land being dominant in the overall landscape of Luoyang; (2) cultivated land holdings in Luoyang are highly spatially autocorrelated, with the 'high-high'-type area being concentrated in the border area directly north and northeast of Luoyang, while the 'low-low'-type area is concentrated in the south and in the municipal area of Luoyang, and being heavily influenced by topography and urbanization. The expansion determined during the study period mainly took place in the Luoyang City, with most of it being transferred from the 'high-low'-type area; (3) elevation, slope and industrial output values from analysis of the bivariate spatial autocorrelation and spatial autoregressive models of the drivers all had significant effects on the amount of cultivated land holdings, with elevation having a positive effect, and slope and industrial output having a negative effect.

Analysis of Heterogeneous Tree-Ring Growths of Pinus densiflora with Various Topographical Characteristics in Mt. Worak Using GIS (GIS 기법을 이용한 지형적 특성에 따른 월악산 소나무 연륜생장의 이질성 규명)

  • 서정욱;김재수;박원규
    • The Korean Journal of Ecology
    • /
    • v.23 no.1
    • /
    • pp.25-32
    • /
    • 2000
  • To analyze the relationship between climatic factors (monthly temperatures and precipitations) and the radial growths or Pinus densiflora with different topographical settings in Worak National Park, Korea, 20 stands were chosen and 10 trees were selected from each stand. After crossdating, each ring-width series was double detrended (standardized) by fitting first a negative exponential or straight regression line and secondly a 60-year cubic spline. The growth patterns coud be categorized by four groups using cluster analysis. Cluster Ⅰ stand has north aspect, but others have south or southwest aspects. Cluster Ⅰ (one), cluster Ⅱ (ten), and cluster Ⅲ (two) stands are located in lower. elevation (305∼580 m), however, cluster Ⅳ (seven) stands are located in higher elevation, mostly in 560~870 m. Cluster Ⅱ and Ⅲ stands are located at similar elevation with the same aspect, however, cluster Ⅱ stands are located on more rocky and stiff slope with shallow soil depth. The response functions were used to examine the difference in the relationships between climatic factors and tree growths among the 4 cluster chronologies. The climatic factors are not limiting the growth in the cluster Ⅰ stand as highly as in other cluster plots because of rather mesic conditions in the north slope. The precipitation in the spring appears to be the main limiting factor in the cluster Ⅱ stands. The topographical characteristics of the sites of cluster Ⅱ, shallow soil depths on the rocky slope in the south aspect at lower elevation, may enhance the sensitivity of growth to moisture stress. In cluster Ⅲ and cluster Ⅳ, winter and spring temperature prior to the growth become more important than for cluster Ⅱ. This pattern is com-mon for Pinus densiflora trees growing in higher. elevation (equation omitted 800 m) in South Korea. It nay be re-lated with preconditioning effects of temperature as the temperature decreases with increasing elevation (cluster Ⅳ) or in the valley (cluster Ⅲ). The results obtained by tree-ring analysis were digitalized by GIS and spatio-temporal information on tree-ring data and topographic setting were analyzed and displayed simultaneously. The results of this study can be used to predict the future change of Pinus densiflora ecosystem to climate change expected in central Korea.

  • PDF

Characteristics of Wind Direction Shear and Momentum Fluxes within Roughness Sublayer over Sloping Terrain (경사가 있는 지형의 거칠기 아층에서 풍향시어와 운동량 플럭스의 특성)

  • Lee, Young-Hee
    • Atmosphere
    • /
    • v.25 no.4
    • /
    • pp.591-600
    • /
    • 2015
  • We have analyzed wind and eddy covariance data collected within roughness sublayer over sloping terrain. The study site is located on non-flat terrain with slopes in both south-north and east-west directions. The surface elevation change is smaller than the height of roughness element such as building and tree. This study examines the directional wind shear for data collected at three levels in the lowest 10 m in the roughness sublayer. The wind direction shear is caused by drag of roughness element and terrain-induced motions at this site. Small directional shear occurs when wind speed at 10 m is strong and wind direction at 10 m is southerly which is the same direction as upslope flow near surface at this site during daytime. Correlation between vertical shear of lateral momentum and lateral momentum flux is smaller over steeply sloped surface compared to mildly sloped surface and lateral momentum flux is not down-gradient over steeply sloped surface. Quadrant analysis shows that the relative contribution of four quadrants to momentum flux depends on both surface slope and wind direction shear.

Assessing forest net primary productivity based on a process-based model: Focusing on pine and oak forest stands in South and North Korea (과정기반 모형을 활용한 산림의 순일차생산성 평가: 남북한 소나무 및 참나무 임분을 중심으로)

  • Cholho Song;Hyun-Ah Choi;Jiwon Son;Youngjin Ko;Stephan A. Pietsch;Woo-Kyun Lee
    • Korean Journal of Environmental Biology
    • /
    • v.41 no.4
    • /
    • pp.400-412
    • /
    • 2023
  • In this study, the biogeochemistry management (BGC-MAN) model was applied to North and South Korea pine and oak forest stands to evaluate the Net Primary Productivity (NPP), an indicator of forest ecosystem productivity. For meteorological information, historical records and East Asian climate scenario data of Shared Socioeconomic Pathways (SSPs) were used. For vegetation information, pine (Pinus densiflora) and oak(Quercus spp.) forest stands were selected at the Gwangneung and Seolmacheon in South Korea and Sariwon, Sohung, Haeju, Jongju, and Wonsan, which are known to have tree nurseries in North Korea. Among the biophysical information, we used the elevation model for topographic data such as longitude, altitude, and slope direction, and the global soil database for soil data. For management factors, we considered the destruction of forests in North and South Korea due to the Korean War in 1950 and the subsequent reforestation process. The overall mean value of simulated NPP from 1991 to 2100 was 5.17 Mg C ha-1, with a range of 3.30-8.19 Mg C ha-1. In addition, increased variability in climate scenarios resulted in variations in forest productivity, with a notable decline in the growth of pine forests. The applicability of the BGC-MAN model to the Korean Peninsula was examined at a time when the ecosystem process-based models were becoming increasingly important due to climate change. In this study, the data on the effects of climate change disturbances on forest ecosystems that was analyzed was limited; therefore, future modeling methods should be improved to simulate more precise ecosystem changes across the Korean Peninsula through process-based models.