• Title/Summary/Keyword: Lowland

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The Post-glacial Vegetation History of the Lowland in Korean Peninsula (한반도 후빙기의 저지대 식생사)

  • 최기룡
    • The Korean Journal of Ecology
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    • v.21 no.2
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    • pp.169-174
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    • 1998
  • This is the review of vegetational history of the post-glacial period in Korea. most of studies for vegetational changes are located in the lowland alluvial plain, especially below the hilly zone of western and eastern coastal regions of Korea. A couple of methods, pollen analysis and radiocarbon dating, have been employed in these studies. These results lead us to establish the pollen zonation in Korea as the followings. Yasuda et al.(1980) classified six period in Yongrang lake of sokcho. These are as follow I. 17,000-15,000yr B.P.: Picea, Abies, Pinus(Haploxylon), Larix stage, II.15,000-10,000yr B.P:Herb, Pteridophyta stage, III.10.000-6,700yr BP.:Quercus stage, IV.6,700-4,500yr B.P.:Pinus, Quercus, Carpinus stage, V.4,500-1,400yr B.P.:Quercus. Pinus stage, VI.1,400yr B.P.-present: Pinus, Herbs stage. Jo(1979) also divided the period into two stages from the outcomes of analysis done in Jumoonjin and other sites I.10,000-6,000yr B.P.:Quercus stage, II.6,000-present: Pinus-Quercus stage, and three substages: IIa.6,000-3,400 yr B.P.:lower Pinus stage, IIb.3,400-2,000yr B.P.:Pinus-Quercus stage, IIc.2,000-present: Pinus stage. Choi(1993, 1996) divided the period into three stages: I.6,000-5,000yr B.P.:Alnus, Quercus stage, II.5,000-4,000yr B.P.: Alnus, Quercus, Pinus stage, III.4,500-2,600yr B.P.: Alnus, Pinus stage. In the period around 6,000yr B.P. distinct dominant species clearly occupied the lowland of the eastern and western coasts. Thus, this strongly supports the fact that even if Korea experienced its warm and wet climate after the lateglacial, it underwent a different environmental change, dry climate, compared to the regions of Japan.

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Carbon stocks and its variations with topography in an intact lowland mixed dipterocarp forest in Brunei

  • Lee, Sohye;Lee, Dongho;Yoon, Tae Kyung;Salim, Kamariah Abu;Han, Saerom;Yun, Hyeon Min;Yoon, Mihae;Kim, Eunji;Lee, Woo-Kyun;Davies, Stuart James;Son, Yowhan
    • Journal of Ecology and Environment
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    • v.38 no.1
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    • pp.75-84
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    • 2015
  • Tropical forests play a critical role in mitigating climate change, and therefore, an accurate and precise estimation of tropical forest carbon (C) is needed. However, there are many uncertainties associated with C stock estimation in a tropical forest, mainly due to its large variations in biomass. Hence, we quantified C stocks in an intact lowland mixed dipterocarp forest (MDF) in Brunei, and investigated variations in biomass and topography. Tree, deadwood, and soil C stocks were estimated by using the allometric equation method, the line intersect method, and the sampling method, respectively. Understory vegetation and litter were also sampled. We then analyzed spatial variations in tree and deadwood biomass in relation to topography. The total C stock was 321.4 Mg C $ha^{-1}$, and living biomass, dead organic matter, and soil C stocks accounted for 67%, 11%, and 23%, respectively, of the total. The results reveal that there was a relatively high C stock, even compared to other tropical forests, and that there was no significant relationship between biomass and topography. Our results provide useful reference data and a greater understanding of biomass variations in lowland MDFs, which could be used for greenhouse gas emission-reduction projects.

Nutritive Evaluation of Forage Plants Grown in South Sulawesi, Indonesia II. Mineral Composition

  • Nasrullah, Nasrullah;Niimi, Mitsuhiro;Akashi, Ryo;Kawamura, Osamu
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.1
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    • pp.63-67
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    • 2004
  • In order to evaluate the nutritive value of the forage plants in South Sulawesi, Indonesia, 266 samples (61 grasses and 65 legumes grown in the dry season, 60 grasses and 80 legumes grown in the rainy season) were collected from the highland and the lowland in 1998 to 2000, and were subjected to the determination of mineral composition. The mean contents of Ca, Mg, P, Na and K in grasses were 0.6, 0.3, 0.5, 0.1 and 2.3%, respectively, and in legumes were 1.8, 0.5, 0.8, 0.1 and 1.7%, respectively. The least-squares analysis of variance demonstrated as follows; For the grasses, Ca content was significantly affected by the year${\times}$season, year${\times}$altitude, and the season${\times}$altitude interactions. Mg content was significantly affected by year and season and P content was significantly affected by altitude, year and by the year${\times}$altitude interaction. For the legumes, Ca content was significantly affected by altitude and the year${\times}$season, season${\times}$altitude and the year${\times}$altitude interactions and Mg content was significantly affected by season or altitude and by the year${\times}$season interaction. These results indicate that Ca content of forage plants grown at the lowland in rainy season was higher than at the highland in dry season. Mg content of forage plants grown at the lowland in dry season was higher than at the highland in rainy season and P content of forage plants grown in the highland was higher than in the lowland.

Classification of the Damaged Areas in the DMZ (Demilitarized zone) by Location Environments (입지 환경 인자를 이용한 DMZ 남측 철책선 주변 훼손지 유형화)

  • Bak, Gi-Ppeum;Kim, Sang-Jun;Lee, Ah-Young;Kim, Dong-Hak;Yu, Seung-Bong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.2
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    • pp.71-84
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    • 2021
  • Restoration of DMZ has come up with the discussion on the peaceful use of the DMZ and the conservation plan of the army. In this study, we aim to identify soil characteristics of 108 sites to figure out environmental conditions around the iron fence of DMZ where vegetation has been removed repeatedly. Based on the soil characteristics and climate variables, hierarchy clustering was performed to categorize sites. As a result, we categorized 108 sites into 4 types: middle elevation region, lowland, East coast lowland, other areas. Group of 'other area' is only high in nutrient and clay proportion. Others are in igneous rock and metamorphic rocks with a high proportion of sand and lower nutrients than the optimum range of growth in Korean forest soil. The middle elevation region has a high altitude, low temperature. The east coast lowland has a high temperature in January and low precipitation. The lowland has a low altitude and high temperature. This category provides the environmental condition around the DMZ fence and can be used to select plants for restoration. The restoration project around the DMZ iron fence should satisfy the security of military plans, which means that functional restoration is prior to ecological restoration such as vegetation management under a power line. Additionally, improvement of soil quality and surface stability through restoration projects is required to enhance the resilience of the ecosystem in DMZ.

Classification of Korean Benthic Macroinvertebrate Types Using the TWINSPAN Clustering and Discriminant Analysis of Environmental Factors Affecting the Distribution of the Types (TWINSPAN 기법을 이용한 한국의 저서성 대형무척추동물의 유형분류 및 유형분포에 영향을 미치는 환경요인에 대한 판별분석)

  • Min, Jeong-Ki;Kim, Dong-Hee;Moon, Jeong-Suk;Kim, Jin-Young;Kong, Dongsoo
    • Journal of Korean Society on Water Environment
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    • v.34 no.6
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    • pp.602-620
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    • 2018
  • Korean benthic macroinvertebrate community from 959 sites and 14 environmental factors that could affect the biological distribution were surveyed and analyzed. The 438 taxa were divided into six groups according to TWINSPAN. Based on the environmental factor values corresponding to each taxon, the average and range of environmental factors for each biological group tended to increase or decrease in eight environmental factors (altitude, slope, current velocity, fraction of fine particles in substrates, turbidity, $BOD_5$, T-N and T-P). As a result of discriminant analysis (hit ratio: 69.6 %), environmental factors that significantly influence the distribution of each biological group were $BOD_5$, altitude, catchment area, T-N, T-P and fraction of fine particles in substrates. The discriminant functions 1 and 2 classified the existing six biological groups (clustered by TWINSPAN) into five (group 1: highland highly sensitive group; group 2: lowland sensitive group, group; 3 and 4: lowland slightly tolerant group; group 5: lowland tolerant group; group 6: lowland highly tolerant group). Most of the benthic macroinvertebrates were identified in the species level. However, a few others were identified in genus or family level, too. Even the organisms belonging to the same genus or family may prefer different environmental factors in the species level, the identification of characteristic of the habitat environment preferred by organism and species level identification of these organisms are utmost. The results of this study may be used as basic information on environmental factors which can be considered in preservation and restoration research for biodiversity.

Degradation of Lowland Forest Landscape and Management Strategy to Improve Ecological Quality in Mt. Baekja and Its Surroundings

  • Cho, Hyun-Je;Cho, Yong-Chan;Lee, Chang-Seok
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.445-452
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    • 2006
  • The number of species and forest area has decreased as urbanization is progressed. The landscape degradation was examined by analyzing vegetation map, satellite image and characteristics of actual vegetation. The study was conducted in Mt. Baekja and its surroundings located on Gyeongsan city, southeastern Korea. As the result of landscape analysis, agricultural field was a characteristic attribute of the study area. Lowlands of this study area were occupied by agricultural field and various plantations. For 15 years from 1987 to 2002, forest area decreased from 2,072.9 ha to 1,853.2 ha, and shape index and fractal dimension of vegetation patches increased from 1.32 to 1.65 and from 1.05 to 1.09, respectively. Pinus densiflora Siebold & Zucco. community showed the highest species diversity, whereas Larix kaempferi (Lamb.) Carriere community showed the lowest species abundance. As forest management implications, monitoring of endangered plant species (Jeffersonia dubia (Maxim.) Benth. & Hook.f. ex Baker & S.Moore), and restoration of lowland forest from plantation to natural forest were discussed. Further, establishment of greenways utilizing existing streams, roadside, and public facilities were recommended.

Development of a Grid Based Two-Dimensional Numerical Method for Flood Inundation Modeling Using Globally-Available DEM Data (범용 DEM 데이터를 이용한 2차원 홍수범람 모형의 개발)

  • Lee, Seung-Soo;Lee, Gi-Ha;Jung, Kwan-Sue
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.659-663
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    • 2010
  • In recent, flood inundation damages by hydraulic structure failures have increased drastically and thus a variety of countermeasures were needed to minimize such damages. A real-time flood inundation prediction technique is essential to protect and mitigate flood inundation damages. In the context of real time flood inundation modeling, this study aims to develop a grid based two-dimensional numerical method for flood inundation modeling using globally-available DEM data: SRTM with $90m{\times}90m$ spatial resolution. The newly-developed model guarantees computational efficiency in terms of geometric data processing by direct application of DEM for flood inundation modeling and also have good compatibility with various types of raster data when compared to a commercial model such as FLUMEN. The model, which employed the leap-frog algorithm to solve shallow water and continuity equations, can simulate inundating flow from channel to lowland and also returning flow from lowland to channel by comparing water levels between channel and lowland in real time. We applied the model to simulate the BaekSan levee break in the Nam river during a flood period from August 10 to 13, 2002. The simulation results had good agreements with the field-surveyed data in terms of inundated area and also showed physically-acceptable velocity vector maps with respect to inundating and returning flows.

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Herbicidal Phytotoxicity in Relation to the Korean Soil Properties (한국(韓國) 경지토양특성(耕地土壤特性)에 관련(關聯)된 제초제(除草劑) 약해(藥害))

  • Ryang, Hwan-Seung;Chun, Jae-Chul
    • Korean Journal of Weed Science
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    • v.2 no.2
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    • pp.122-128
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    • 1982
  • This paper deals with herbicidal phytotoxicity which may occur because of unique properties of the Korean soils. Analysis of the Korean lowland and upland soils reveals that about 50% of the total area belongs to sandy loam and sandy gravel soils and most of both lowland and upland soils consists of kaolinite clay mineral. The chemical properties such as organic matter, pH, and cation exchange capacity show very low values by which there have been several instances of the herbicidal phytotoxicity occurred throughout the country. In addition, the paper emphasizes the need for selection and use of herbicides in the Korean soils.

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Stability Analysis for Grain Yield of Lowland Rice for the Largest Rice-Growing Region of Eastern india

  • Bose, L.K.;Mohanty, A.;Kar, M.K.;Nagaraju, M.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.2
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    • pp.136-140
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    • 2004
  • Twenty-one lowland rice genotypes were evaluated for their stability parameters with respect to grain yield in a multi locational trial at five different sites of Eastern India viz. CRRI, Cuttack (Orissa); OUAT, Bhubaneswar (Orissa); CRS, Masodha (UP); RAU, Pusa (Bihar) and RARS, North Lakhimpur (Assam). Pooled analysis of variance reflects existence of genotype x environment interactions and contribution of both linear and nonlinear components to genotype (G) x environment (E) interactions. Through stability parameter analysis it was found that Rayda $\textrm{B}_3$, CR 778-95 and CR 661-236 were suitable for over all environments where as Sabita, OR 1334-16 and OR 1358-RGA-4 were suitable for rich environments. PSR 1209-2-3-2, CR 780-1937, Ambika, OR 877-ST-4-2 and CR 662-2211 were identified for poor environments.