The Effect of rbanization in the surfacewater runoff城市化对地表径流的影响.pptVIP

The Effect of Urbanization to the surface-water runoff The comparison between the urbanized and undeveloped zones * Outline Objective/Study area Data Sources Backgrounds Map Creation Analysis Question Build a Basemap of the City of Austin Apply the precipitation data (time-series) on the study areas Compare the flow pattern in regards to the land cover Objective Study Areas The Shoal Creek The Barton Creek 1. Aerial Photo: Texas Natural Resources Information http://www.tnris.state.tx.us/update3.cfm?Tx_County_Name=Travis 2. Land Cover: National Land Cover Institute 3. Digital Elevation Model: USGS Dataset 4. Gage station data: USGS Dataset /GIS/metadata/usgswrd/XML/streamgages.xml 5. Stream Network data: City of Austin GIS Data Sets ftp://coageoid01.ci.austin.tx.us/GIS-Data/Regional/coa_gis.html 6. Precipitation Data: Hourly/Daily Rain Data from NOAA’s Forecast Systems /hourly_precip.html Data Sources Background The sources of flooding in Austin area Unique geographic and atmospheric condition Creeks Urban flooding Hurricane and tropical storms The Land Cover of Austin, Texas Building a Basemap Watershed of both creeks The completed Basemap Gathering discharge and precipitation data USGS Streamgage data Precipitation data Analysis Sep. 7, 2002 81.00 7.60 2.49 6.70 0.01 7 0.00 5.60 2.44 5.40 0.00 6 Discharge (cfs) Day Shoal Barton Lost Barton Spring SH71 Loop 360 Sep. 2002 Analysis 212.00 14.00 2.52 20.00 0.00 8 81.00 7.60 2.49 6.70 0.01 7 Discharge (cfs) Day Shoal Barton Lost Barton Spring SH71 Loop 360 Sep. 2002 Sep. 8, 2002 Analysis 9.10 33.00 2.53 32.00 0.00 9 212.00 14.00 2.52 20.00 0.00 8 Discharge (cfs) Day Shoal Barton Lost Barton Spring SH71 Loop 360 Sep. 2002 Sep. 9, 2002 Analysis Conclusion The land cover largely influences the discharge rate and time to reach the peak point. Soil layer runoff runoff impermeable layer Question ? * * * *