• Title/Summary/Keyword: Soil Geography

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Spatial assessment of soil contamination by heavy metals from informal electronic waste recycling in Agbogbloshie, Ghana

  • Kyere, Vincent Nartey;Greve, Klaus;Atiemo, Sampson M.
    • Environmental Analysis Health and Toxicology
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    • v.31
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    • pp.6.1-6.10
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    • 2016
  • Objectives This study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana. Methods A total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination ($C_{deg}$), we analyzed the individual contribution of each heavy metal contamination and the overall $C_{deg}$. We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination. Results Results from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall $C_{deg}$. Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas. Conclusions Our results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and $C_{deg}$, indicating soil contamination in AEPS with the nine heavy metals studied.

Development of an urban forest management system based on information of topography, soil and forest type (지형, 토양 및 임상정보에 기초한 도시림 관리시스템 개발)

  • Lee, Woo-Kyun;Son, Yo-Whan;Song, Chul-Chul;Chung, Kee-Hyun;Kim, Yoon-Kyoung;Ryu, Soung-Ryoul;Kim, Hyun-Sup
    • Journal of Environmental Impact Assessment
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    • v.8 no.3
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    • pp.61-76
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    • 1999
  • For the effective management of urban forest, a variety of informations on urban forest needs to be accurately measured and effectively used in decision-making processes. This study aims at developing an urban forest management system with reference to GIS and making it possible to effectively manage urban forests. A detailed forest type map were constructed with the help of aerial photograph and terrestrial inventory. A geographical map in terms of slope, aspect and altitude were also prepared by Digital Elevation Model(DEM). A soil type map containing chemical characteristics were also made through soil analysis. These thematic maps which contain informations on forest type, geography and soil were digitalized with reference to GIS, and an urban forest management system of user interface were developed. With the help of this urban forest management system, various spatial and attribute informations which need for urban forest management could be easily used in decision-making processes in relation to urban forest.

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SOIL ORGANIC CARBON APPRAISAL IN A SEMI-EVERGREEN FOREST, EASTERN GHATS OF INDIA AS A RESULT OF DEGRADATION - A GEOSPATIAL STUDY

  • Jayakumar, S.;Ramachandran, A.;Bhaskaran, G.;Cho, Hyoung-Sig;Heo, Joon
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.98-100
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    • 2007
  • Tropical forests have variety of biodiversity values, which provide invaluable services to the living being on earth. In the recent years, tropical forests are regarded as valuable global resources that act as sink for carbon dioxide in order to mitigate global climatic change. In many parts of the world, tropical forests are being rapidly cleared by various means. Soil organic carbon (SOC) is concentrated in the upper 12 inches of the soil. So it is readily depleted owing to the degradation activities. In the present study, it was aimed to assess the magnitude of disturbance in the availability of SOC in a semi- evergreen forest, situated in the Eastern Ghats of Tamil Nadu, India. The forest density of this region was mapped with QuickBird satellite data. Intensive field soil sampling and floristic study were conducted to estimate the SOC status in different density classes and to identify the species availability. The SOC density ranged from 274.06 t/ha to 147.84 t/ha in the very dense and degraded semi-evergreen forest respectively. The SOC content was also varied from 3.70 to 1.83 % in the very dense semi-evergreen and medium semi-evergreen forests respectively. The species composition in different density classes was also varied considerably. As a result of this study, it was identified that the disturbance to forests by various means not only affect the density of forests but also affect the below ground SOC status proportionately.

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Numerical Modeling of Water Transfer among Precipitation, Surface Water, Soil Moisture and Groundwater

  • Chen, Xi;Zhang, Zhicai;Chen, Yongqin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2006.05a
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    • pp.2-11
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    • 2006
  • In the processes of hydrological cycle, when precipitation reaches the ground surface, water may become surface runoff or infiltrate into soil and then possibly further percolate into groundwater aquifer. A part of the water is returned to the atmosphere through evaporation and transpiration. Soil moisture dynamics driven climate fluctuations plays a key role in the simulation of water transfer among ground surface, unsaturated zone and aquifer. In this study, a one-layer canopy and a four-layer soil representation is used for a coupled soil-vegetation modeling scheme. A non-zero hydraulic diffusivity between the deepest soil layer modeled and groundwater table is used to couple the numerical equations of soil moisture and groundwater dynamics. Simulation of runoff generation is based on the mechanism of both infiltration excess overland flow and saturation overland flow nested in a numerical model of soil moisture dynamics. Thus, a comprehensive hydrological model integrating canopy, soil zone and aquifer has been developed to evaluate water resources in the plain region of Huaihe River basin in East China and simulate water transfer among precipitation, surface water, soil moisture and groundwater. The newly developed model is capable of calculating hydrological components of surface runoff, evapotranpiration from soil and aquifer, and groundwater recharge from precipitation and discharge into rivers. Regional parameterization is made by using two approaches. One is to determine most parameters representing specific physical values on the basis of characterization of soil properties in unsaturated zone and aquifer, and vegetations. The other is to calibrate the remaining few parameters on the basis of comparison between measured and simulated streamflow and groundwater tables. The integrated modeling system was successfully used in the Linhuanji catchment of Huaihe plain region. Study results demonstrate that (1) on the average 14.2% of precipitation becomes surface runoff and baseflow during a ten-year period from 1986 to 1995 and this figure fluctuates between only 3.0% in drought years of 1986, 1988, 1993 and 1994 to 24.0% in wet year of 1991; (2) groundwater directly deriving from precipitation recharge is about 15.0% t of the precipitation amount, and (3) about half of the groundwater recharge flows into rivers and loses through evaporation.

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Remote Sensing Applications for Malaria Research : Emerging Agenda of Medical Geography (원격탐사 자료를 이용한 말라리아 연구 : 보건지리학적 과제와 전망)

  • Park, Sunyurp
    • Journal of the Korean association of regional geographers
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    • v.18 no.4
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    • pp.473-493
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    • 2012
  • Malaria infection is sensitively influenced by regional meteorological conditions along with global climate change. Remote sensing techniques have become an important tool for extraction of climatic and environmental factors, including rainfall, temperature, surface water, soil moisture, and land use, which are directly linked to the habitat qualities of malaria mosquitoes. Improvement of sensor fidelity with higher spatial and spectral resolution, new multinational sensor development, and decreased data cost have nurtured diverse remote sensing applications in malaria research. In 1984, eradication of endemic malaria was declared in Korea, but reemergence of malaria was reported in mid-1990s. Considering constant changes in malaria cases since 2000, the epidemiological management of the disease needs careful monitoring. Geographically, northmost counties neighboring North Korea have been ranked high in the number of malaria cases. High infection rates in these areas drew special attention and led to a hypothesis that malaria dispersion in these border counties might be caused by north-origin, malaria-bearing adult mosquitoes. Habitat conditions of malaria mosquitoes are important parameters for prediction of the vector abundance. However, it should be realized that malaria infection and transmission is a complex mechanism, where non-environmental factors, including human behavior, demographic structure, landscape structure, and spatial relationships between human residence and the vector habitats, are also significant considerations in the framework of medical geography.

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A Reinvestigation on Key Issues Associated with the Yimjin(1712) Boundary Making and Demarcation: The Distribution of Soil Piles and the Location of 'Suchul(水出)' written on the Mukedeng's Map (임진정계 경계표지 토퇴의 분포와 목극등 지도에 표시된 '수출(水出)'의 위치)

  • Lee, Kang-Won
    • Journal of the Korean Geographical Society
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    • v.52 no.1
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    • pp.73-103
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    • 2017
  • This paper reports the distribution of soil piles set up during the Yimjin(1712) Boundary Making and Demarcation(YBMD). Through the survey on the distribution of soil piles the location of 'Suchul'(水出: seepage zone) could be identified. The endpoint soil pile set up on the east-south bank of Heishigou(黑石溝) stream locates on $42^{\circ}04^{\prime}20.09^{{\prime}{\prime}}N$, $128^{\circ}16^{\prime}08.42^{{\prime}{\prime}}E$. The west beginning point of soil piles distributed in the south side of Tuhexian road locates on $42^{\circ}02^{\prime}20.14^{{\prime}{\prime}}N$, $128^{\circ}18^{\prime}53.40^{{\prime}{\prime}}E$. And the east endpoint of them locates $42^{\circ}01^{\prime}32.97^{{\prime}{\prime}}N$, $128^{\circ}21^{\prime}24.59^{{\prime}{\prime}}E$. From the west beginning point to the soil pile located in 2.1km distance from the beginning point, the distribution direction is west-east. The direction of soil piles after them is northwest-southeast. The total real length of soil piles distributed in the south side of Tuhexian(圖和線) road is about 4.2km more or less. The location of 'Suchul' written on the Mukedeng's map locates on $42^{\circ}01^{\prime}30.36^{{\prime}{\prime}}N$, $128^{\circ}21^{\prime}3.62^{{\prime}{\prime}}E$, The point locates in southeastward 222m distance from the soil piles endpoint of the south side of Tuhexian road. In reference of these reports this paper develops some reinterpretation on the YBMD.

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Sulfur Cycle in the Rehabilitated Forest Catchment in Tanakami Mountain, Kansai District, Japan (일본 칸사이 지방 타나카미 산지의 황폐지 복구 산림유역 내 황(黃)순환에 관한 연구)

  • Kim, Su-Jin;Ohte, Nobuhito;Park, Jong-Kwan
    • Journal of the Korean Geographical Society
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    • v.44 no.4
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    • pp.429-446
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    • 2009
  • To understand the sulfur flux and cycle in the forest catchment, the hydrological processes and chemical variation of soil solution, groundwater and stream water were analyzed at the Matsuzawa catchment located in the Kiryu Experimental Basin, Shiga Prefecture, central Japan. Unsaturated soil layer at the upper slope of catchment was the source area of ${SO_4}^{2-}$, and deep soil layer and groundwater were the sink zone of ${SO_4}^{2-}$. The vertical distribution of ${SO_4}^{2-}$ concentrations in groundwater affected seasonal variation of ${SO_4}^{2-}$ concentrations in stream water, as groundwater level changed. It is reasonable to assume that each hydrological processes in the forest catchment play an important roles in the retention and discharge of ${SO_4}^{2-}$.

GIS Based Analysis of Landslide Factor Effect in Inje Area Using the Theory of Quantification II (수량화 2종법을 이용한 GIS 기반의 인제지역 산사태 영향인자 분석)

  • Kim, Gi-Hong;Lee, Hwan-Gil
    • Spatial Information Research
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    • v.20 no.3
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    • pp.57-66
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    • 2012
  • Gangwon-do has been suffering extensive landslide dam age, because its geography consists mainly of mountains. Analyzing the related factors is crucial for landslide prediction. We digitized the landslide and non-landslide spots on an aerial photo obtained right after a disaster in Inje, Gangwon-do. Three landslide factors-topographic, forest type, and soil factors-w ere statistically analyzed through GIS overlap analysis between topographic map, forest type map, and soil map. The analysis showed that landslides occurred mainly between the inclination of $20^{\circ}$ and $35^{\circ}$, and needleleaf tree area is more vulnerable to a landslide. About soil properties, an area with shallow effective soil depth and parent material of acidic rock has a greater chance of landslide.

Processes of Thufur Disintegration Mt. Halla (한라산 유상 구조토의 붕괴 프로세스와 요인)

  • Kim, Tae-Ho
    • Journal of the Korean association of regional geographers
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    • v.12 no.4
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    • pp.437-448
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    • 2006
  • Bare-topped thufur is called as frost scars, implying the rupturing stage of vegetated mounds, Field observations and measurements provide empirical information on the process and factors of thufur disintegration in Mt. Halla, Initial bare patches on mound apexes are scaled up by continuous removal of soil and vegetation, resulting in the formation of crater-like thufur, Frost action plays a primary role in thufur disintegration, In particular, pipkrake loosens soil particles within the bare patches and subsequently accelerates the degradation of vegetated mounds during periods with frequent diurnal freeze-thaw cycle and high soil moisture, Deflation also has an impact on thufur breakup in that the bare patches usually lack upper dark brown soil and are covered with granules, Withered shrubs such as Juniperus chinensis var. sargentii are frequently observed in frost scars and disrupted mounds, indicating that thufur disintegration has been probably influenced by global warming.

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Some Proposed Indices of Structural Regeneration of Secondary Forests and Their Relation to Soil Properties

  • Aweto, Albert Orodena
    • Journal of Forest and Environmental Science
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    • v.37 no.4
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    • pp.292-303
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    • 2021
  • Studies that relate the structure of tropical regrowth vegetation to soil properties are generally lacking in the literature. This study proposes three indices for assessing the structural regeneration of secondary forests. They are: (1) the tree diameter class, (2) the plant life form and (3) the woody/herbaceous plants ratio indices. They were applied to assess the regeneration status of forest regrowth vegetation (aged 1-10 years), derived savanna regrowth vegetation in south western Nigeria, and to secondary forests in different stages of succession in Columbia and Venezuela, Bolivia, Mexico in South and Central America and semi-arid savanna in Ethiopia and seasonal deciduous forest successional stages in India. In all the cases, the indices increased with increasing age of regrowth vegetation and hence, with increasing structural complexity of regenerating vegetation. The tree diameter class index increased from 32.1% in a 9-year secondary forest to 69.0% in an 80-year-old secondary forest in Columbia and Venezuela and from 0.4% in a 1-year fallow to 20.9% in 10-year regrowth vegetation in southwestern Nigeria. In semi-arid savanna in northern Ethiopia, the woody/herbaceous plants ratio index increased from 18.1% in a 5-year protected grazing enclosure to 75.1% in 15-year protected enclosure, relative to the status of 20-year enclosure. The indices generally had correlations of 0.6-0.90 with species richness and Simpson's/Margalef's species diversity, implying that they are appropriate measures of ecosystem development over time. The proposed indices also had strong and positive correlations with soil organic carbon and nutrients. They are therefore, significant indicators of fertility status.