Chapter 11 Grid Exercises INTRODUCTION In this chapter, you can test your understanding of GIS tools for application of problcm- solving in the Grid GIS world. The following table summarizes the Grid GIS tools that were covered in Chapter 8. Grid Arithmetic 0 erators: + Addition. - Subtraction. * Multiplication. / Division. Selection Tools: TEST Returns 1 /0 based on loqical query SELECT Returns original / NODATA based on loqical query. CON Returns user-specified values based on loqical query. Groupin!l Tools: RECLASS Chanqe cell values based on remap table assiqnments REGIONGROUP Groups cells of the same value that touch each other. Distance Tools: EXPAND Expands user-specified cell values (analoqous to BUFFER ). EUCDISTANCE Computes the distance to closest non-NODATA cell for each cell. I Optimal Path Tools: COSTDISTANCE Estimates the minimum accumulative cost to resource cells. COSTPATH Estimates the least cost path from source to destination cells. TOPo!lraphic Tools: SLOPE Estimates rate of maximum slope chanqe for each cell. ASPECT Estimates the slope direction for each cell. 183 © 2002 Taylor & Francis 184 PRACTICAL GIS ANALYSIS REAL ESTATE APPLICATION You have grids of elevation, roads, and ownership. You want to find land owned by the Fairbanks Northstar Borough that is above 500 feet elevation (out of the ice fog), on a easterly, southerly, or westerly slope, and within 100 meters of a road. Your elevation values is in meters. Fill in the following flowchart with the appropriate Grid tools: I ELEVATION I OWNERSHIP ROADS FBKSNSB NEAR_ROAD 1= owned by FBKSNSB 1= within 100 meters O=owned by other O=too far from road NO-ICEFOG 1= elevation> 500 ft I ASPECT I O=too low in elevation I FBKNS-RD WARM_SLOPE 1= owned by FBKS and 1=Aspect from 90 to 270 within 100 m of road O=Aspect from northerly slope O=other SITES 1=Aspect from 90 to 270 . above 500 ft elevation owned by FBKSNSB and within 100 m of road © 2002 Taylor & Francis GRID EXERCISES 185 WATERSHED APPLICATION You have a grid of vegetation types, and a grid of watersheds. You want a table showing the area of each watershed and the area of black spruce in each watershed. Each grid cell is 25 by 25 meters. Fill in the following flowchart with the appropriate grid operations to solve your GIS problem: VEG BLK_SPRUCE 1=White Spruce 0= No 2= Black Spruce 1= Yes, a black 3= Aspen/Birch spruce cell WATERSHEDS 1= Rock Creek 2= Glade Creek 3= Moose Creek 1 BLKSPR SHEDS lumn called Ha 1= Blk. Spruce in-Rock Creek Ie 2= Blk. Spruce in Glade Creek cell area into hectares 3= Blk. Spruce in Moose Creek Tables Module Add column called Ha Get table Convert cell area into hectares Tables Module Add co Get tab ___ Convert © 2002 Taylor & Francis 186 PRACTICAL GIS ANALYSIS WATERFOWL HABITAT ANALYSIS You have grids of lakes. One grid is from early summer and the other grid is from late summer. You want to create a grid of the best lakes for waterfowl habitat lakes that had at least 1 hectare of exposed mudflats in late summer due to drawdown of the lake water level. The cell size of each grid is 10 meters. Fill in the following flowchart to solve your GIS problem. EARLY 0= nonlake cells 1=Iakes in early summer DRAWDOWN O=Not 1= Cells that are dry in late LATE summer but were 0= nonlake cells water in early summer 1=lakes in late summer GROUPS Groups of drawdown cells BIG_AREAS Drawdown areas exceeding 1 hectare 1100 cells) © 2002 Taylor & Francis GRID EXERCISES 187 GROUNDWATER APPLICATION You have a grid of well locations, gas station locations, soils, and parcel ownership that contains the address of the owner of each parcel. Outline what tools you would use to develop a text file of all well owners that have wells on sandy textured soils within a kilometer of a gas station. SOILS 1=Sand 2= Loamy sand 8= Silty clay 9=Clay STATIONS O=Not gas station 1=Gas station cells Text file of addresses of well owners within 1 km of a gas station with well on sandy texture soils SANDY O=Not sandy texture 1=Sandy textures STATION_1KM O=Not near gas station 1=Within 1 km of gas station WELLS O=Not a well cell 1=Well cells CONTACTS Grid of owners with wells within 1 km of a gas station on sandy texture soils SANDY_KM O=Not 1=Sandy texture and within 1 km of station , SITES O=Not 1=Wells on sandy texture and within 1km of station PARCELS Grid of parcel IDs and owner addresses © 2002 Taylor & Francis 188 PRACTICAL GIS ANALYSIS MOOSE HABITAT ANALYSIS You have grids of moose locations, random locations and vegetation types. You want to estimate the mean distance of moose and random locations to the nearest willow cell. All grid cells are 10 meters in size. Fill in the following flowchart with the appropriate grid operations to solve your GIS problem: VEG Vegetation type grid WILLOW Willow grid DIST_WILLOW Distance to nearest willow cell MOOSE O=Not a moose cell 1=Moose location cell MOOSE_DIST For each moose location, distance to nearest willow cell MOOSE_DIST.TBL Table containing mean distance to nearest willow cell for moose locations RANDOM O=Not a random location 1=Random location cells RAND_DIST For each random location, distance to nearest willow cell RAND_DIST.TBL Table containing mean distance to nearest willow cell for random locations © 2002 Taylor & Francis . Chapter 11 Grid Exercises INTRODUCTION In this chapter, you can test your understanding of GIS tools for application of problcm- solving in the Grid GIS world. The following. hectares Tables Module Add co Get tab ___ Convert © 2002 Taylor & Francis 186 PRACTICAL GIS ANALYSIS WATERFOWL HABITAT ANALYSIS You have grids of lakes. One grid is from early summer and the other. 1km of station PARCELS Grid of parcel IDs and owner addresses © 2002 Taylor & Francis 188 PRACTICAL GIS ANALYSIS MOOSE HABITAT ANALYSIS You have grids of moose locations, random locations and vegetation types.