Maps, Aerial Photos and Maps, Aerial Photos and Satellite Images on Satellite Images on

Environment ChangeEnvironment Change- A Case Study of the - A Case Study of the

Chenyoulan Chenyoulan River Watershed, Taiwan River Watershed, Taiwan

I-Chun FanResearch FellowResearch Fellow, Institute of History and Philology, , Institute of History and Philology,

Executive OfficerExecutive Officer, Center for Geographic Information Science,, Center for Geographic Information Science,

Research Center for Humanities and Social Sciences, Research Center for Humanities and Social Sciences,

Academia SinicaAcademia Sinica

OverviewOverview

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Archiving Maps, Remote Sensing ImageryArchiving Maps, Remote Sensing Imagery at GIS Center, Academia Sinicaat GIS Center, Academia Sinica

What the Maps and Remote Sensing Imagery can What the Maps and Remote Sensing Imagery can Help on the Studies of Enviroment ChangesHelp on the Studies of Enviroment Changes

Case study of Landscape Changes in the Case study of Landscape Changes in the Chenyoulan River Watershed, TaiwanChenyoulan River Watershed, Taiwan

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Digital Archives of Maps and Remote Digital Archives of Maps and Remote Sensing Imagery at GIS CenterSensing Imagery at GIS Center URL: http://gis.rchss.sinica.edu.tw/mapdapURL: http://gis.rchss.sinica.edu.tw/mapdap

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Topographic Map of Taiwan (1882)

Formoza Island(1845) Aerial Photo (1946)

WebGIS-based Remote Sensing Imagery Management System

Query System

Digitizing Process

Remote Sensing Aerial Photos33,892 aerial photos of Taiwan during the 1940s. 25,788 aerial photos of China during the 1950s. More tahn15,000 rolls of aerial photo negatives total, (c. 2,000,000 sheets)Historical MapsAround 100,000 maps of China.Around 30,000 maps of Taiwan.

Remote Sensing Aerial Photos33,892 aerial photos of Taiwan during the 1940s. 25,788 aerial photos of China during the 1950s. More tahn15,000 rolls of aerial photo negatives total, (c. 2,000,000 sheets)Historical MapsAround 100,000 maps of China.Around 30,000 maps of Taiwan.

Content Management SystemsContent Management Systems

Issues Clarified through Maps, Issues Clarified through Maps,

Aerial Photos and Satellite Aerial Photos and Satellite Images Images in Historical Perspectivein Historical Perspective

Issues of Land Use and Socio-economic Issues of Land Use and Socio-economic DevelopmentsDevelopments

(Deforestation, Cultivation, Roads)(Deforestation, Cultivation, Roads)

Hillside Disasters Hillside Disasters (Landslides, Deris (Landslides, Deris

Flows) Flows)

Long Time Long Time ScaleScale

Settlement DistributionSettlement Distribution

Geomorphological Change Geomorphological Change and River Rehabilitationand River Rehabilitation

Environmental Conservation IssuesEnvironmental Conservation Issues

Historical transitionHistorical transition

Short Time Short Time

ScaleScale

Spatio-temporal GIS Platform

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Study AreaStudy Area- The Chenyoulan River - The Chenyoulan River Watershed Watershed Area: 448 km2Area: 448 km2

Length: 42.4 kmLength: 42.4 km With Steep SlopeWith Steep Slope Many River Many River

TerracesTerraces High Turbidity High Turbidity

Stream FlowStream Flow Many Landslides Many Landslides

& Debris Flows & Debris Flows occurred occurred

National Forest National Forest Area & Aboriginal Area & Aboriginal Reserved landsReserved lands

Rectification & Georeferencing Rectification & Georeferencing of Maps, Aerial Photos and of Maps, Aerial Photos and Satellite Images Satellite Images

Using Watershed boundaries as Ground Control Points

Application of the High Resolution Application of the High Resolution DTMs DTMs to Generate Precise Watershed to Generate Precise Watershed Boundaries Boundaries 5m 10m 20m 30m 40m

2D Images of the2D Images of theChenyoulan River WatershedChenyoulan River Watershed

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3D-Platform of the3D-Platform of theChenyoulan River WatershedChenyoulan River Watershed

Geomorphological Changes of Geomorphological Changes of

the River Terrace and the River Terrace and Landslides (3D)Landslides (3D)

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The Spatio-temporal The Spatio-temporal Framework of the Chenyoulan Framework of the Chenyoulan River Watershed,River Watershed,1946~2010- Extended Issues1946~2010- Extended Issues

Spatial correlation Spatial correlation between between deforestation, deforestation, cultivation, roads cultivation, roads and landslidesand landslides

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Land Use Land Use of the of the Chenyoulan River Chenyoulan River WatershedWatershed from 1946-2002from 1946-2002

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Reserved Area of the Indigenous Reserved Area of the Indigenous People in the Chenyoulan River People in the Chenyoulan River WatershedWatershed -Restricted Stages (1946)-Restricted Stages (1946)--Green: Deforestation areaGreen: Deforestation area; ; Red: Cultivation Red: Cultivation ; ; Pink: Landslides Pink: Landslides

Reserved Area of the Indigenous Reserved Area of the Indigenous Peoples in the Chenyoulan River Peoples in the Chenyoulan River WatershedWatershed - Interim between Restricted and Developed Stages (1971)- Interim between Restricted and Developed Stages (1971) - -Green: Deforestation areaGreen: Deforestation area; ; Red: CultivationRed: Cultivation; ; Pink: Landslides Pink: Landslides

Reserved Area of the Indigenous Reserved Area of the Indigenous People in the Chenyoulan River People in the Chenyoulan River WatershedWatershed - Contemporary Situation(2011)- Contemporary Situation(2011)--Green: Deforestation areaGreen: Deforestation area; ; Red: CultivationRed: Cultivation; ; Pink: Landslides Pink: Landslides

Spatial Correlation between Spatial Correlation between Deforestation, Cultivation, Roads Deforestation, Cultivation, Roads and Landslides by 1946and Landslides by 1946Large deforestation areasLarge deforestation areasFew landsilde occurred in deforestation area Few landsilde occurred in deforestation area

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Spatial Correlation between Spatial Correlation between Deforestation, Cultivation, Roads Deforestation, Cultivation, Roads and Landslides by1971and Landslides by1971Deforestation area reduced and fragmentedDeforestation area reduced and fragmentedIncrease of cultivation and roadsIncrease of cultivation and roadsSmall landslides increased Small landslides increased

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Spatial Correlation between Spatial Correlation between Deforestation, Cultivation, Roads Deforestation, Cultivation, Roads and Landslides by 2002and Landslides by 2002Deforestation area was fully recoveredDeforestation area was fully recoveredLand cultivation grew with road developmentLand cultivation grew with road developmentMany new landsildes occurred along roadsMany new landsildes occurred along roads

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ConclusionConclusion Visualization of Landscape Changes. Visualization of Landscape Changes.

Spatial Qualitative to Quantitative Spatial Qualitative to Quantitative Analysis.Analysis.

Building A Spatio-temporal Platform Building A Spatio-temporal Platform Serves for Interdisciplinary Approach to Serves for Interdisciplinary Approach to the Environmental Issues the Environmental Issues

Thank you for your attention !