• Title/Summary/Keyword: landuse changes

Search Result 65, Processing Time 0.025 seconds

Development of lumped model to analyze the hydrological effects landuse change (토지이용 변화에 따른 수문 특성의 변화를 추적하기 위한 Lumped모형의 개발)

  • Son, Ill
    • Journal of the Korean Geographical Society
    • /
    • v.29 no.3
    • /
    • pp.233-252
    • /
    • 1994
  • One of major advantages of Lumped model is its ability to simulate extended flows. A further advantage is that it requires only conventional, readily available hydrological data (rainfall, evaporation and runoff). These two advantages commend the use of this type of model for the analysis of the hydrological effects of landuse change. Experimental Catchment(K11) of Kimakia site in Kenga experienced three phases of landuse change for sixteen and half years. The Institute of Hydrology offered the hydrological data from the catchment for this research. On basis of Blackie's(l972) 9-parameter model, a new model(R1131) was reorganized in consideration of the following aspects to reflect the hydrological characteristics of the catchment: 1) The evapotranspiration necessary for the landuse hydrology, 2) high permeable soils, 3) small catchment, 4) input option for initial soil moisture deficit, and 5) othel modules for water budget analysis. The new model is constructed as a 11-parameter, 3-storage, 1-input option model. Using a number of initial conditions, the model was optimized to the data of three landuse phases. The model efficiencies were 96.78%, 97.20%, 94.62% and the errors of total flow were -1.78%, -3.36%, -5.32%. The bias of the optimized models were tested by several techniques, The extended flows were simulated in the prediction mode using the optimized model and the data set of the whole series of experimental periods. They are used to analyse the change of daily high and low-flow caused by landuse change. The relative water use ratio of the clearing and seedling phase was 60.21%, but that of the next two phases were 81.23% and 83.78% respectively. The annual peak flows of second and third phase at a 1.5-year return period were decreased by 31.3% and 31.2% compared to that of the first phase. The annual peak flow at a 50-year return period in the second phase was an increase of only 4.8%, and that in the third phase was an increase of 12.9%. The annual minimum flow at a 1.5-year return period was decreased by 34.2% in the second phase, and 34.3% in the third phase. The changes in the annual minimum flows were decreased for the larger return periods; a 20.2% decrease in the second phase and 20.9% decrease in the third phase at a 50-year return period. From the results above, two aspects could be concluded. Firstly, the flow regime in Catchment K11 was changed due to the landuse conversion from the clearing and seedling phade to the intermediate stage of pine plantation. But, The flow regime was little affected after the pine trees reached a certain height. Secondly, the effects of the pine plantation on the daily high- and low-flow were reduced with the increase in flood size and the severity of drought.

  • PDF

Analysis of LANDSAT Images of Estimated Vegetation Index and Paddy Area (수도경작지 식생변화 추정을 위한 여주, 양평, 광주 LANDSAT 데이터 분석)

  • Jung, Won-Kyo;Rim, Sang-Kyu;Shin, Jae-Sung
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.30 no.2
    • /
    • pp.135-139
    • /
    • 1997
  • Vegetation indices were analyzed from the LANDSAT images of Yeoju, Kwangju and Yangpyong Gun of Kyunggi Province, obtained on September 22, 1983 and September 12, 1994, to evaluate the changes in landuses. It was found that there were notable changes in the landuses in the observed area over 11 years. Particularly, in Choweol Myun of Kwanju Gun, in Yangpyong Eup of Yangpyong Gun, and in Heungcheon Myun of Yeoju Gun, decrease in the area under vegetatin was most remarkable. These changes in the area under vegetatin are considered as the results of the construction of highways and the expansion of urban areas. The LANDSAT images overestimated the area under rice cultivation, when compared to the official statistic year book. However, it was found that the areas of the land under rice cultivation estimated by LANDSAT images for each Myun were close enough to those from the official statistics suggesting that the LANDSAT images can be used for the estimation of landuse status.

  • PDF

The Analysis of Landscape Structure due to the Landcover Change - Case Study in Kyongsan City - (토지이용변화에 따른 경산시의 경관구조 분석)

  • Jeong, Seong-Gwan;Oh, Jeong-Hak;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.5 no.3
    • /
    • pp.9-18
    • /
    • 2002
  • Landscape, the land mosaics, is combined with human and natural environment. Landuse and landcover changes are an important factor that changes structure and function of regional landscape. In this study, the changes of landcover and landscape structures are examined in Kyongsan between 1985 and 1997, using Landsat TM images and landscape indices. The results of this study are as follows; First, according to the classification of landcover, forest and agriculture areas have decreased as a result of urban expansion. Second, forest fragmentation has been brought by development; So forest healthiness has weakened. It is proved that urban expansion has happened in agriculture land. Third, a variety of landuse types around forest have changed from agriculture-oriented types to the ones mixed with urban and agriculture areas between 1985 and 1997.

  • PDF

An Impact Assessment of Climate and Landuse Change on Water Resources in the Han River (기후변화와 토지피복변화를 고려한 한강 유역의 수자원 영향 평가)

  • Kim, Byung-Sik;Kim, Soo-Jun;Kim, Hung-Soo;Jun, Hwan-Don
    • Journal of Korea Water Resources Association
    • /
    • v.43 no.3
    • /
    • pp.309-323
    • /
    • 2010
  • As climate changes and abnormal climates have drawn research interest recently, many countries utilize the GCM, which is based on SRES suggested by IPCC, to obtain more accurate forecast for future climate changes. Especially, many research attempts have been made to simulate localized geographical characteristics by using RCM with the high resolution data globally. To evaluate the impacts of climate and landuse change on water resources in the Han-river basin, we carried out the procedure consisting of the CA-Markov Chain, the Multi-Regression equation using two independent variables of temperature and rainfall, the downscaling technique based on the RegCM3 RCM, and SLURP. From the CA-Markov Chain, the future landuse change is forecasted and the future NDVI is predicted by the Multi-Regression equation. Also, RegCM3 RCM 50 sets were generated by the downscaling technique based on the RegCM3 RCM provided by KMA. With them, 90 year runoff scenarios whose period is from 2001 to 2090 are simulated for the Han-river basin by SLURP. Finally, the 90-year simulated monthly runoffs are compared with the historical monthly runoffs for each dam in the basin. At Paldang dam, the runoffs in September show higher increase than the ones in August which is due to the change of rainfall pattern in future. Additionally, after exploring the impact of the climate change on the structure of water circulation, we find that water management will become more difficult by the changes in the water circulation factors such as precipitation, evaporation, transpiration, and runoff in the Han-river basin.

Analysis of Land Use Change within Four Major River Areas Using High-Resolution Air-Photographs: The Case of the Nakdong River Basin (고해상도 항공사진을 이용한 4대강 하천구역 내 토지이용변화 분석 - 낙동강 유역을 사례로)

  • Park, Soo-Kuk;Kim, Jin;Lee, Kil-Jae;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.16 no.4
    • /
    • pp.171-188
    • /
    • 2013
  • Landuse changes and cadastral information error categories in the four major river areas were analyzed for the use of policy data as cadastral re-arrangement of national and public lands would be required, using high-resolution air-photographs and cadastral maps before and after the river development. The study sites were the river areas of 40km around four dams of the Nakdong river where their landuses were changed most. As the results, national and public lands reached 79.9% of land parcels and 93.3% of land areas of the study sites similar with those of the four river areas, 84.3% of land parcels and 85.5% of land areas. The landuse classification of the study sites before the four river development was consisted most of 'river'(71.6%) and 'rice field'(12.3%), but after the development the 'river' was reduced to 42.7% and 'park area'(19.6%) including sport fields and 'mixed lots'(20.8%) were increased. Also, 86.7% of land parcels before the development could be reduced after the development if administrative districts and land ownerships were not considered. Cadastral information error categories can be found as cadastral polygon missing, polygon overlap, location and boundary non-coincidence, small polygon generation, and non-coincidence between cadastral boundary and river boundary. Landuse change monitoring method using air-photographs will be useful to analyze landuse state through fast information aquisition and to manage properties of national and public lands such as river areas.

Changes in Rural Settlement Development System and its Effects on the facilities & houses of Village settlements in Rural area (농촌마을 개발제도의 변천과 농촌마을에 대한 영향)

  • Cho, Joon-Beom;Choi, Chan-Hwan
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.1 no.2
    • /
    • pp.109-117
    • /
    • 1999
  • The purpose of the study is to evaluate the Rural Settlement Development(RSD) driven by government in historical view, and its effects on the facilities and houses of rural village in the country. Through the study, we have come to the results that the major concerns of the RSD projects since 1950s has been transferred to as following. First, the reformation of inter-facility; dressing room, kitchen, bath-house, etc of rural houses, from that of outer facility; roof, fence and etc. Secondly, the substantial objects of the projects of village settlement improvement have been changed from partial reformation of individual houses, public facilities, etc early, to comprehensive reformation by master plan for village settlement recently. Lastly, those have been established that the process of planning village settlement available to carry out landuse division and the various program for village improvement, based on its inherent circumstances.

  • PDF

Evaluation of Applicability and Hydrologic Parameter Calibration for HSPF Model using Expert System for HSPF (매개변수 보정 전문가시스템을 이용한 HSPF 모형의 수문 매개변수 보정 및 적용성 평가)

  • Kim, Sung Min;Kim, Sang Min
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.4
    • /
    • pp.13-20
    • /
    • 2013
  • The purpose of this study was to evaluate the applicability of the HSPEXP expert system for the calibration of the Hydrological Simulation Program - Fortran (HSPF) for the study watershed. HSPEXP offers advice to the modeler, suggesting parameter changes that might result in better representation of a river basin and provides explanations supporting the recommended parameter changes. The study watershed, Sancheong, is located within the Nakdong River Basin and having the size of $1,072.4km^2$. Input data for the HSPF model were obtained from the landuse map, digital elevation map, meteorological data and others. Water flow data from 2006 to 2008 were used for calibration and from 2009 to 2010 were for validation. Using the HSPEXP expert system, hydrological parameters were adjusted based on total volume, then low flows, storm flows, and finally seasonal flows. For the calibration and validation period, all the HSPEXP model performance criteria were satisfied.

Analysis of Watershed Runoff and Sediment Characteristics due to Spatio-Temporal Change in Land Uses Using SWAT Model (SWAT 모형을 이용한 시.공간적 토지 이용변화에 따른 유량 및 유사량 특성분석)

  • Shin, Yong-Chul;Lim, Kyoung-Jae;Kim, Ki-Sung;Choi, Joong-Dae
    • KCID journal
    • /
    • v.14 no.1
    • /
    • pp.50-56
    • /
    • 2007
  • In this study, the Soil and Water Assessment Tool (SWAT) model was used to assess spatiotemporal effects on watershed runoff and sediment characteristics due to land uses changes from 1999 to 2002 at the small watershed, located in Chuncheon-si, Gangwon province. The annual average flow rate of Scenario I (long-term simulation using land use of 1990), II (long-term simulation using land use of 1996), III(long-term simulation using land use of 200) and IV(simulation using land use of 1990, 1995, and 2000) in long-term simulation) using the SWAT model were 29,997,043 m3, 29,992,628 m3, 29,811,191 m3 and 29,931,238 m3, respectively. It was shown that there was no significant changes in estimated flow rate because no significant changes in land uses between 1990 and 2000 were observed. The annual average sediment loads of Scenarios I, II, III and IV for 15 year period were 36,643 kg/ha, 45,340 kg/ha , 27,195 kg/ha and 35,545 kg/ha, respectively. The estimated annual sediment loads from Scenarios I, II, and III, were different from that from the scenario IV, considering spatio-temporal changes in land use and meterological changes over the years, by 10%, 127%, and temporal changes in land use and meterological changes over the years, by 10%, 127%, and 77%. This can be explained in land use changes in high soil erosion potential areas, such as upland areas, within the study watershed. The comparison indicates that changes in land uses upland areas, within the study watershed. The comparison indicates that changes in land uses can affect on sediment yields by more than 10%, which could exceed the safety factor of 10% in Total Maximum Daily Loads (TMDLs). It is, therefore, recommended that not only the temporal analysis with the weather input data but also spatial one with different land uses need to be considered in long-term hydrology and sediment simulating using the SWAT model

  • PDF

Urbanized land-use / landscape patterns in the city's countryside (도시근교농촌의 토지이용 및 경관의 변화)

  • 김유일;이애란
    • Journal of Korean Society of Rural Planning
    • /
    • v.3 no.2
    • /
    • pp.71-80
    • /
    • 1997
  • The city's countryside is adjusting to change by urbanization. The recent changes in rural landuse and damages of local landscape characteristics are very serious. But, few studies address the relationship between land-use and quality of landscape for these area. The aim of this study is to clarify causes and problems of the change through investigating changes of landscape as a function of land-use. The results are as follows 1) The change of landscape can be seen as a functional of land-use. Landscapes are characterized by changes of regional environments. These are the urban-rural fringe area which need special consideration for urban development and also for rural landscape quality. 2) 11 types of landscape patterns are found for landscape management. these are Regional commercial area, Apartment development, Recreation & seisure, Golfs, Housing complex, Industrial complex, Vinyl house, Rural village, Evaded facilities, Rivers, Cultural heritages. These landscape types are explained as 'stimuli-responses model'in Bryant's Forces of urbanization. 3) The policy implications of these study are as follows : First is the necessity of landscape management in Grown Management Zone and Natural Reserved Zone in the Metropolitan level, Second is the necessity of development control in semi- agricultural area. The last is the necessary of long range management plan in the urban-rural fringe area.

  • PDF

Estimation of Regional Water Balance in Various Climate Change Scenarios (기후변화 시나리오에 따른 지역 물수지 추정)

  • 김만규
    • The Korean Journal of Quaternary Research
    • /
    • v.13 no.1
    • /
    • pp.53-65
    • /
    • 1999
  • It is only possible by Physical based Water Balance Models such as $BROOK_{TOP}$ developed by me to estimate regional water balances caused by changes of regional ecosystem, which result in climate change, change of vegetation due to climate change, artificial landuse change, etc. This study estimates regional water balances of mid-north agricultural and forest regions in Germany using $BROOK_{TOP}$-Water Balance Model with climate change scenarios developed by PIK in Germany and GCM Scenarios developed by Praha University in Czech. Developing Water Resource Change Estimation System such as this study for global warming with considering climate, surface and underground conditions provides the basis of system development for surface-, groundwater-, cultivation-, ecosystem-, natural emergency-management, landuse and regional planing.

  • PDF