• Title/Summary/Keyword: forest cover

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Kansas Vegetation Mapping Using Multi-Temporal Remote Sensing Data: A Hybrid Approach (계절별 위성자료를 이용한 미국 캔자스주 식생 분류 - 하이브리드 접근방식의 적용 -)

  • ;Stephen Egbert;Dana Peterson;Aimee Stewart;Chris Lauver;Kevin Price;Clayton Blodgett;Jack Cully, Jr,;Glennis Kaufman
    • Journal of the Korean Geographical Society
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    • v.38 no.5
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    • pp.667-685
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    • 2003
  • To address the requirements of gap analysis for species protection, as well as the needs of state and federal agencies for detailed digital land cover, a 43-class map at the vegetation alliance level was created for the state of Kansas using multi-temporal Thematic Mapper imagery. The mapping approach included the use of three-date multi-seasonal imagery, a two-stage classification approach that first masked out cropland areas using unsupervised classification and then mapped natural vegetation with supervised classification, visualization techniques utilizing a map of small multiples and field experts, and extensive use of ancillary data in post-hoc processing. Accuracy assessment was conducted at three levels of generalization (Anderson Level I, vegetation formation, and vegetation alliance) and three cross-tabulation approaches. Overall accuracy ranged from 51.7% to 89.4%, depending on level of generalization, while accuracy figures for individual alliance classes varied by area covered and level of sampling.

Simulation of the Reduction Effect of Soil Loss Using SWAT Model (SWAT 모형을 이용한 토양유실량 저감효과 모의)

  • Jeong, Jin-Kweon;Kim, Hwan-Gi
    • Journal of Environmental Impact Assessment
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    • v.17 no.4
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    • pp.243-253
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    • 2008
  • The purpose of this study was to simulate the reduction effect of soil loss in the Yongdam reservoir watershed using SWAT model. To evaluate accuracy for flow and sediment yield of SWAT model, calibration was performed for the period from Jan. 2002 to Dec. 2003, and the verification for Jan. 2005 to Dec. 2005. The calibration and the verification were carried out using data observed at the Cheoncheon gaging station. The $R^2$ and EI values in terms of a flow were 0.8 and 0.78 respectively for calibration, whereas they for verification were 0.88 and 0.86 respectively. In terms of a sediment yield, they were 0.7 and 0.48 respectively for calibration, whereas for verification were 0.64 and 0.54 respectively. As a results from model simulation, annual mean soil loss rates in terms of forest, paddy and upland were 0.02 ton/ha/yr, 0.15 ton/ha/yr and 7.58 ton/ha/yr, respectively. The results show that the land use type of a upland has more significant impact on a total soil loss as well as a sediment yield than other types of land use. The sediment delivery ratio was determined to be about 0.35. In this study 2 land cover change scenarios for upland area were considered. These scenarios were used an input to SWAT model in order to evaluate their impact on soil loss and sediment delivery. The results show that a reduction of the upland area would reduce the soil loss and sediment yield.

Study on the Classification of Gyeonggi-Do's Conservation Areas by Improvement of National Land Environmental Assessment (국토환경성평가 개선을 통한 경기도지역의 보전지역 구분에 관한 연구)

  • Lee, Dong-Kun;Sung, Hyun-Chan;Jeon, Seong-Woo;Lee, Sang-Dae;Kim, Kwi-Gon;Kim, Jae-Uk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.4
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    • pp.43-51
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    • 2005
  • Due to rapid and reckless economic development, natural resources of the national land have been damaged and polluted. Accordingly, the necessity for environment-friendly development has been on the rise and many have made efforts to assess the environmental value of the national land. This study divides the conservation areas by means of using relative elevation, slope, and development of housing land based on environmental evaluation of the national land. The relative elevation is obtained by the difference of altitude at the edge of the forest patch extracted from the land cover classification map based on the ridgeline, and the slope is obtained by environment-oriented land suitability analysis. The development of housing land is classified in accordance with the progress of each project. Twenty-six evaluation criteria are divided into five different grades using the minimal indicator approach and then sub-divided into ten grades by means of using the following two scenarios. The first one uses the weight of input materials while the second one relies on the size of patches that are emphasized in landscape ecology. Consequently, such a study demonstrated the following results. The method relying on the weight of input materials revealed the limitation of emphasizing input materials excessively, whereas the method of considering the size of patches resulted in the division of conservation areas that embody regional characteristics. This study is meaningful in that it classifies the conservation areas by reflecting the regional characteristics and the ecological values of animals and plants.

Predicting the Potential Distributions of Invasive Species Using the Landsat Imagery and Maxent : Focused on "Ambrosia trifida L. var. trifida" in Korean Demilitarized Zone (위성영상과 Maxent를 활용한 생태계교란생물 분포지역 예측 : DMZ의 단풍잎돼지풀을 대상으로)

  • Park, Hyun-Chul;Lim, Jeong-Cheol;Lee, Jung-Hwan;Lee, Gwan-Gyu
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.20 no.1
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    • pp.1-12
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    • 2017
  • This study has been carried out for the purpose of predicting the potential habitat sites of invasive alien plants in the DMZ and providing the basic data for decision-making in managing the future DMZ natural environment. From 2007 to 2015, this study collected the data for the advent of Ambrosia trifida var. trifida through fieldwork around the DMZ area, and simulated the potential distribution area of Ambrosia trifida var. trifida using Maxent model among the models of species distributions. As a result, it showed that the potential distribution area of the Ambrosia trifida var. trifida was concentrated in the western DMZ with relatively low altitude and scanty in the central east regions with relatively high elevation and forest cover rate. Because the invasive alien vegetation is a significant threatening factor in the agriculture and restoration of ecology and it costs a lot to restore the area already invaded by invasive alien vegetation, advance precautions are necessary to prevent biological invasions. It is expected that it is possible to predict the disturbed ecosystems through this study for the efficient land use within DMZ in the future and to apply this study in setting up the areas for the development and conservation within the DMZ.

Evaluation of Runoff Prediction from Managed Golf Course using WEPP Watershed Model (WEPP 모형을 이용한 골프장 잔디 관리에 따른 유출특성 모의)

  • Choi, Jaewan;Shin, Min Hwan;Ryu, Ji Chul;Kum, Donghyuk;Kang, Hyunwoo;Cheon, Se Uk;Shin, Dong Seok;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.28 no.1
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    • pp.1-9
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    • 2012
  • It has been known that Golf course could impose negative impacts on water-ecosystem if pollutant-laden runoff is not treated well. It is important to control non-point source and re-use treated wastewater from the golf course to secure water quality of receiving waterbodies. At golf courses, the rainfall-runoff is affected by various practices to manage grasses. In many hydrological modelings, especially in simple rainfall-runoff modeling, effects on runoff of plant growth and cutting are not considered. In the study, the water erosion prediction project (WEPP), capable of simulating plant growth and various management, was evaluated for its runoff prediction from golf course under grass cutting and irrigation. The %Difference, $R^2$ and the NSE for runoff comparisons were 1.15%, 0.93 and 0.92 for calibration, and 18.12%, 0.82 and 0.88 for validation period, respectively. In grass cutting scenario, grass height was managed to be 18~25 mm. The estimated runoff was decreased by 27%. The difference in estimated total runoff was 11.8% depending on irrigation. As shown in this study, if grass management and irrigation are well-controlled, water quality of downstream areas could be obtained.

The Influence on the Runoff Charateristics by the Land Use in Small Watersheds (II) (소유역의 토지이용이 유출특성에 미치는 영향 (II))

  • Choi, Ye-Hwan;Choi, Joong-Dae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.178-182
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    • 2005
  • In the forthcoming 21C, the development of cultural lives depends on that the water demand will increase or not. On the opposite site of that circumstance, many factors of the small watersheds will influence directly on how to cover the surface of watersheds with land use, no planning developing watersheds, and the rearrangement of small rivers. Especially as the extraordinary climatic Phenomena, exhaust of $CO_2$ and destruction of 03 layer, water resource and water foresting content of the small watersheds will be decreased by confusing on the malting a plan of water resources. For example, those are Typhoon Rusa in 2002, Typhoon Maemi in 2003 and heavy storms in 2004. This study area has three group and one of them having three small watersheds, total five small watersheds. That is, Sabukmyeon small watersheds in Chuncheon, Three small watersheds in Wonju(Jeoncheon, Jupocheon and Hasunamcheon), and Suipcheon in Yanggu-Gun which are located far away each other three group and different precipitation data. According to the land use such as dry field(or farm), rice field, forest land. building site and others in small watersheds, the amount of runoff will be impacted by monthly precipitation. The comparison between the runoff was getting from Kajiyama Formula and calculated runoff from multi-linear regressed equations by land use Percentage was performed with different precipitation data and different small watersheds. Its correlations which are estimated by coefficient of correlation will be accepted or not, as approached 1.0000 values. As the monthly water resources amount is estimated by multi-linear regressed equations with different precipitation data and different small watersheds having no gauging station, we make a plan in order to demand and supply the water quantity from small river watersheds during return periods.

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ANALYSIS OF SPATIAL FACTORS AFFECTING DENGUE EPIDEMICS USING GIS IN THAILAND

  • Nakhapakorn Kanchana;Tripatht Nitin;Nualchawee Kaew;Kusanagt Michiro;Pakpien Preeda
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.774-777
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    • 2005
  • Dengue Fever(DF) and Dengue haemorrhagic fever(DHF) has become a major international public health concern. Dengue Fever(DF) and Dengue haemorrhagic Fever (DHF) is also still the major health problem of Thailand, although many campaigns against it have been conducted throughout the country. GIS and Remotely Sensed data are used to evaluate the relationships between socio-spatial, environmental factors/indicators and the incidences of viral diseases. The aim of the study is to identify the spatial risk factors in Dengue and Dengue Haemorrhagic Fever in Sukhothai province, Thailand using statistical, spatial and GIS Modelling. Preliminary results demonstrated that physical factors derived from remotely sensed data could indicate variation in physical risk factors affecting DF and DHF. The present study emphasizes the potential of remotely sensed data and GIS in spatial factors affecting Dengue Risk Zone analysis. The relationship between land cover and the cases of incidence of DF and DHF by information value method revaluated that highest information value is obtained for Built-up area. A negative relationship was observed for the forest area. The relations between climate data and cases of incidence have shown high correlation with rainfall factors in rainy season but poor correlation with temperature and relative humidity. The present study explores the potential of remotely sensed data and GIS in spatial analysis of factors affecting Dengue epidemic, strong spatial analysis tools of GIS. The capabilities of GIS for analyst spatial factors influencing risk zone has made it possible to apply spatial statistical analysis in Disease risk zone.

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Late Pleistocene Paleovegetation and Paleoclimate of the Uiwang Area Based on Pollen Analysis (화분 분석을 통한 의왕시 지역의 후기 플라이스토세 고식생 및 고기후 연구)

  • Chung, Chull-Hwan;Lim, Hyoun-Soo;Yoon, Ho-Il
    • Journal of the Korean earth science society
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    • v.31 no.7
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    • pp.698-707
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    • 2010
  • The Late Pleistocene pollen record from the Poil-dong, Uiwang, Kyunggi-do, reveals that mixed coniferous and deciduous broadleaved forests were spread along with herb and fern understory. Palynofloral changes reflect climate fluctuations. From ca. 43,100 to 41,900 cal. yr BP, a mixed coniferous and deciduous broadleaved forest combined with open grassland occupied the study area, which indicates cooler condition than today. During the period of ca. 41,900-41,200 cal. yr BP, along with fern understory a decrease in subalpine conifers and an increase in temperate deciduous broadleaved trees suggest a climatic amelioration. A climatic deterioration, as evidenced by an increase in subalpine conifers and a decrease in the density of vegetation cover, occurred from ca. 41,200 to 39,700 cal. yr BP.

Characteristics of the Home Range and Habitat Use of the Greater Horseshoe Bat (Rhinolophus ferrumequinum) in an Urban Landscape (도심 경관에 서식하는 관박쥐의 행동권 및 서식지 이용 특성)

  • Jeon, Young Shin;Kim, Sung Chul;Han, Sang Hoon;Chung, Chul Un
    • Journal of Environmental Science International
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    • v.27 no.8
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    • pp.665-675
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    • 2018
  • The purpose of this study was to identify the characteristics of the home range and habitat use of Rhinolophus ferrumequinum individuals that inhabit urban areas. The bats were tracked using GPS tags. For analysis of the home rage, Minimum Convex Polygon (MCP) and Kernel Home Range (KHR) methods were used. The landscape types of all positional information were analyzed using ArcGIS 9.3.1 (ESRI Inc.). The average home range of 16 R. ferrumequinum individuals was $68.63{\pm}25.23ha$, and the size of the overall home range for the females ($85.49{\pm}25.40ha$) was larger than that for the males ($51.76{\pm}8.30ha$). The highest average home range for the males was found in August ($61.21{\pm}0.01ha$), whereas that for the females was found in September ($112.27{\pm}5.94ha$). The size of 50% KHR ranged from a minimum of 13.26 ha to a maximum of 31.00 for the males and a minimum of 8.02 ha to a maxinum of 42.16 ha for the females, showing no significant differences between the two sexes. In addition, males and females showed no differences in the size of 50% KHR in the monthly comparisons. However, the females showed differences in the size of their core area between periods before and after giving birth. The comparisons between 100% MCP and 50% KHR showed that the types of habitats used by R. ferrumequinum were mostly forest areas, including some farmlands. In addition, comparisons with a land cover map showed that the proportion of broad-leaved forests was the highest, followed by that of mixed forests.

Management Strategies to Conserve Soil and Water Qualities in the Sloping Uplands in Korea (한국의 경사지 밭의 토양 및 물의 보전 관리 전략)

  • Yang, Jae-E.;Ryu, Jin-Hee;Kim, Si-Joo;Chung, Doug-Young
    • Korean Journal of Agricultural Science
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    • v.37 no.3
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    • pp.435-449
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    • 2010
  • Soils in the sloping uplands in Korea are subject to intensive land use with high input of agrochemicals and are vulnerable to soil erosion. Development of the environmentally sound land management strategy is essential for a sustainable production system in the sloping upland. This report addresses the status of upland agriculture and the best management practices for the uplands toward the sustainable agriculture. More than 60% of Korean lands are forest and only 21% are cultivating paddy and upland. Uplands are about 7% of the total lands and about 62% of the uplands are in the slopes higher than 7%. Due to the site-specificity of the upland, many managerial and environmental problems are occurring, such as severe erosion, shallow surface soils with rocky fragments, and loadings of non-point source (NPS) contaminants into the watershed. Based on the field trials, most of the sloping uplands were classified as Suitability Class III-V and the major limiting factor was slope and rock fragments. Due to this, soils were over-applied with N fertilizer, even though N rate was the recommendation. This resulted in decreases in yield, degradation of soil quality and increases in N loading to the leachate. Various case studies drew management practices toward sustainable production systems. The suggested BMP on the managerial, vegetative, and structural options were to practice buffer strips along the edges of fields and streams, winter cover crop, contour and mulching farming, detention weir, diversion drains, grassed waterway, and slope arrangement. With these options, conservation effects such as reductions in raindrop impact, flow velocity, runoff and sediment loss, and rill and gully erosion were observed. The proper management practice is a key element of the conservation of the soil and water in the sloping upland.