Date post: | 03-Jan-2016 |
Category: |
Documents |
Upload: | helen-myra-lester |
View: | 217 times |
Download: | 0 times |
Are People Ready for Raster Digital Soil Survey Data?
Janis BoettingerAmy Rohman
Utah State University
Suzann Kienast-BrownUSDA-NRCS, Utah
Rationale
• Publicly available soil survey maps– Vector Polygon– Digital• USA - True• World - True
– Review of Global Digital Soil Spatial Data» James Thompson, West Virginia University, in
Grunwald et al. (accepted) SSSAJ
Rationale
• If soil survey maps were available in alternate forms…– Raster (pixel) digital
…what would people’s perceptions & preferences be?
Are People Ready for Raster Digital Data?
Hypotheses
• People ARE ready for raster digital data• Perceptions & preferences of map influenced
by factors– Age– Area of work/study– Prior experience with soil survey maps
Methods & Materials• Developed interview questionnaire– Demographic information• Age groups• Education• Areas of Work/Study
– Assessed experience with soil survey• Establish baseline of experience
– Custom Soil Survey Report of Part of Cache Valley, Utah
– 3 Maps: UT602, Bear River Migratory Bird Refuge• 3 Qualities rated High, Medium, or Low
Map Qualities
• Visual appeal• Conveying information about the spatial
distribution of soils• Determining the soil type(s) mapped at a
specific location– High– Medium– Low
Methods & Materials• 65 Interviews – conducted in person, one-on-one– Suzann Kienast-Brown
• NRCS Soil Scientist & RS-GIS Specialist, Utah• About 15 interviews
– NRCS, USFS, Arts community in northern Utah
– Amy Rohman • Undergraduate Research Assistant• Natural Resources major
– Summer and fall following freshman year
• About 50 interviews– Diverse sample of USU students & faculty, family, friends
• Opportunity to educate people about soil survey
Methods & Materials• Results summarized – Histograms, descriptive statistics– Categories High, Medium, Low
• Ranked 1, 2, 3, respectively
• Statistical analysis– Kolmogorov-Smirnov Test (K-S Test)
• Non-parametric – No assumptions regarding normality
• Compares cumulative distribution functions of two samples– D-statistic = Maximum distance between cumulative distribution
functions
• Significantly different at P=0.05
Visual Appearance
D = 0.446, P<0.001
D = 0.431, P<0.001
Color pixel maps (B and C) rated higher for visual appearance than B&W polygon map.No other statistically significant differences
Work/Study: Ag/NR vs. Other
No significant differences (at P=0.05) between groups for all 3 map qualities
Prior SS Use vs. No Prior SS Use
D = 0.349, P=0.048*; Polygon lines over air photo: Conveying info on soil spatial distribution
Prior SS Use vs. No Prior SS Use
D = 0.349, P=0.048*; Color pixel map over air photo: Visual Appearance
Prior SS Use vs. No Prior SS Use
Prior SS Use: No significant differences (at P=0.05) between maps for all qualities
Prior SS Use vs. No Prior SS Use
Prior SS Use: No significant differences (at P=0.05) between maps for all qualities
D=0.580, P<0.001
Prior SS Use vs. No Prior SS Use
Prior SS Use: No significant differences (at P=0.05) between maps for all qualities
D=0.568, P<0.001
D=0.500, P<0.001
Summary
• Overall (N=65) – Color pixel maps (both) rated higher for visual
appearance that B&W polygon maps– No significant differences in rating B&W poygon
vs. color pixel maps for• Conveying info on spatial distribution of soils• Determining soil type(s) mapped for specific location
Summary
• B&W polygon map rated higher: Conveying information on spatial distribution of soils– Prior soil survey experience (N=21)
• Color pixel over air photo base map rated higher: Visual appearance– No prior soil survey experience (N=44)
Summary
• Prior soil survey use– No significant differences in ratings of map
qualities for all maps
• No prior soil survey use– Color pixel maps (both) rated higher for visual
appeal
Conclusions
• Prior soil survey use influenced ratings – Visual appeal of B&W polygon vs. color pixel– B&W polygon for conveying information on spatial
distribution of soils
Conclusions
• Prior soil survey use influenced ratings – Visual appeal of B&W polygon vs. color pixel– B&W polygon for conveying information on spatial
distribution of soils
• No differences between maps for gaining information, regardless of prior soil survey use– Spatial distribution of soils– Determining soil (s) mapped at specific location