Key Words: Remote Sensing , Geographic Information Systems
Abstract
It always follows a huge lost after the disaster happens. It's more serious in Yushan National Park cause its wide area. It always takes a lot of people, goods and materials to relieve the victims of a disaster. If we can find out the affect carried by those disaster immediately, we can make better policy decision to rebuild and recovery plan. Our study use Remote Sensing technology and Geographic Information System to analysis the Environments Transition in Yushan National Park after earthquake happened in September 21 in 1999 and the typhoon happened in August 1 in 1996.and find out if any facilities damaged on these two disasters. We attempt to offer a powerful suggestion for National park management organization and will be helpful when they want to rebuild the facilities broken in the disasters.
I.Introduction
It always follows a huge lost after the disaster happens. It's more serious in National Park cause its wide area. It's more important to distribute the succor resource before we send the People, goods and materials to relieve the victims of a disaster. Our study trying to use remote sensing technology monitor the transitions of land cover after the disasters. And we also analyze the effect of the disaster with the assistance of Geographic information systems. For this purpose, we choice Yushan National Park to deliberate the earthquake happened in September 21 in 1999 and the typhoon happened in August 1 in 1996 effects. We hope our research can offer a powerful suggestion for National park management organization and will be helpful when they want to rebuild the facilities broken in the disasters.
II.Methodology
Our research wants to find out the relationship between disaster and transitions of land cover. For this purpose we used Remote sensing technology, Geographic Information Systems, land cover classification theory and environmentally sensitive area correlation studies. First we choose the National park in middle part of Taiwan - Yusan National Park. The central region of Yusan National Park takes 10 hectare, which covered Nanto, Kaohsiung, Hualien and Jangyi four counties. There are four rivers and 100 mountains inside. Just like the other National Park in Taiwan the land cover monitor and management become the biggest problem for the management organization. This problem especially effects after two huge disasters in middle part of Taiwan. Typhoon Hobo effects at August 1, 1996 and the earthquake happened at September 21, 1999.
We Use three SPOT images that pictured in 1993,1996 and 1999. Last two images are pictured just after typhoon and earthquake. And all three images are level 10 standard images. Classify images to four classes to see if anything changes during the disasters. And respectively compare the land cover situation between two images to see what changes since 1993 to 1999 in Yusan National Park. At last, we respectively overlay the land cover map, geologic map, topographic map and stature map to find out the relationship between these land factor and different disasters. According to some reference collected from R.O.C. we also delimit the environment sensitivity area at Yusan National Park.
III.Research Topics
This research aims at the land cover of Yusan National Park after hazard. The research topics are as follows:
- An analysis of land cover after disaster in Yusan National Park.
- Land covers transition of Yusan National Park since 1993 to 1999.
- Bare ground distribution analysis.
- Disasters Sensitivity analysis.
To do these research topics in traditional methods always takes lots of time. Our research offers a fast and worthy method for environment monitoring and analysis of National Park disaster.
1.Land Cover Analysis
First, We make an image enhancement for classification reference. Than we simply used supervise and Unsupervised methods on classification progress. Caring about mountainous region always have lots of shadow, we separate the image to Shadow part and the other in progress. And we also use air photos and rainy records to modify the misconstruction between real water area and temporary water cause by the big rain during image pictured. After Classification procedure, we progress the image to four classes. They are bare, wood, grass and water. The distribution Area and percentage at 1993,1996 and 1999 are given in table 1.
