GIS for Environmental Science

1. GIS for Environmental Science ENSC 3603 Class 18 3/12/09

2. Topics for Today • GIS Implementation Phases continued • Soil Survey • Soil Analysis

3. GIS Implementation Phases • Assessment and evaluation of the current situation; • Development of a business concept; • Identification and specification of user requirements; • Identification and acquisition of data; • Benefit-cost analysis; • Devising a strategic plan; • Choice of hardware and software; • Defining and obtaining the necessary expertise; • Choosing a GIS supplier; • System implementation; • Operation and maintenance of the system • (Bernhardsen, 1999)

4. Benefit-cost analysis • Justification usually begins with an effort to identify and assign a price to the benefits and cost of adopting a GIS. • What are the Costs of using current methods? • Will using a GIS improve efficiency enough to justify the cost of implementation and maintenance.

5. Devising a strategic plan • Business management consists of two general categories: strategic and tactical. • Strategic management is laying out the overall long-term course of an enterprise. • Tactical management is taking the short-term actions that keep the enterprise on the course provided by the strategic plan (Kay and Edwards).

6. Strategic plan Examples Arkansas Division of Agriculture http://division.uaex.edu/news_publications/strategic_plan/strategic_plan.pdf Tucson, AZ Water http://www.terrasw.com/tucwater/statplan/default.htm Ontario, CA City Plan http://www.ci.ontario.ca.us/index.cfm/3306

7. Choice of hardware and software • The right choices are essential. • Can be easy in that technical characteristics and prices can be compared. • Can be difficult because future applications are unknown and computer technologies change continuously. (Bernhardsen)

8. Defining and obtaining the necessary expertise • Will you train “in house” or hire someone with experience? • If you train current employees, how long will that take and will their GIS duties compete with other work duties on the job? • Consultants are not essential. If needed they can guide the process.

9. Choosing a GIS supplier • Factors that will affect GIS acquisition: • Procedural requirements of your organization • The characteristics of the planned system • System Acquisition Steps: • Request for Qualifications • Request for Information • Request for Proposals • Receipt and evaluation of proposals • Benchmark Test • Negotiation and contract • Site preparation • Hardware and software installation • Acceptance testing (Tomlinson)

10. Choosing a GIS supplier • Selection Criteria • Functionality – will it perform required functions • Cost • Training Availability and quality • System capacity/ scalability • System speed • System support • Vendor reliability (stability, market share, references from other users) (Tomlinson)

11. System implementation • Site Preparation: are the servers and network connections available for system installation? • Hardware and software installation: The complexity of the system will determine if the vendor will provide this service. Often, the vendor and the client are involved. • Acceptance testing: Does the installed system meet the criteria bid.

12. Operation and maintenance of the system • Continue to provide training support and upgrades to the system.

13. Soil Survey • Soil Survey is “a systematic examination, description, classification, and mapping of the soils in a given area.” • Brady and Weil. 1996

14. Soil Survey • Cooperative effort between the NRCS, Land Grant Universities and Counties where Survey is being conducted. • You can get print versions if available at: USDA/NRCS and Cooperative extension service • NRCS Web Soil Survey http://websoilsurvey.nrcs.usda.gov/app/

15. Soil Survey Components • Mapping of the soils • Characterization of the Mapping Units • Classification of the Mapping Units • Correlation to other Soil Surveys • Interpretation of the soil suitability for various land uses

16. Soil Survey Components • Map Units: a collection of the areas which have similar defined soil properties. Due to these similar soil properties, interpretations can be made for use and management of the soils in the Mapping Unit • Map Units have a two letter code that is Capital then lower case, this is usually followed by a slope class code ( a Capital letter form A to F) • Example: CaB = Captina silt loam, 1 to 3 percent slopes Le = Leaf silt loam

18. Information Provided by Soil Survey 1. Properties of Soil Map Units color permeability stoniness depth to bedrock pH structure salinity texture slope H2O availability horizon thickness engineering properties erosion hazard and other physical and chemical properties 2. Position on the Landscape 3. Percent Area in the Landscape 4. Capacities Yield for crop, pasture and vegetable Suitability for silviculture or forestry, floriculture or flowering plants, recreation, wildlife and water infrastructure Engineering potentials and hazards

19. Captina • Captina Series - Missouri Distribution • The Captina series consists of deep, moderately well drained soils on uplands. These soils formed in a thin layer of loess and in cherty sediments. They have a fragipan. Permeability is moderate in the upper part of the profile and slow in the fragipan. Slopes range from 2 to 9 percent. • Typical pedon of Captina silt loam, 2 to 5 percent slopes, 2,200 feet south and 800 feet west of the northeast corner of sec. 22, T. 26 N., R. 3 E. • A—0 to 5 inches; brown (10YR 4/3) silt loam, light yellowish brown (10YR 6/4) dry; weak fine granular structure; very friable; many fine and medium roots; common fine pores; common worm channels and casts; very strongly acid; clear wavy boundary. BE—5 to 12 inches; yellowish brown (10YR 5/4 and 5/6) silt loam; weak fine subangular blocky structure; friable in the E part, firm in the B part; common fine and medium roots; common fine pores; common worm channels; few fine pieces of carbonized material; very strongly acid; gradual smooth boundary.

20. Bt—12 to 26 inches; strong brown (7.5YR 5/6) silty clay loam; moderate medium subangular blocky structure; firm; common fine and medium roots; few faint clay films on faces of peds; common fine pores; few worm channels and casts; very pale brown (10YR 7/3) silt loam in old root channels; extremely acid; clear wavy boundary.Bx1—26 to 30 inches; light yellowish brown (10YR 6/4) and strong brown (7.5YR 5/6) silty clay loam; moderate fine subangular blocky structure; brittle in place; firm; few fine roots; few fine pores; about 10 percent chert fragments; extremely acid; abrupt wavy boundary.Bx2—30 to 36 inches; mottled brownish yellow (10YR 6/8), strong brown (7.5YR 5/6), and light brownish gray (10YR 6/2) very cherty silty clay loam; moderate fine subangular blocky structure; brittle in place; firm; about 60 percent chert fragments; extremely acid; clear wavy boundary.Bx3—36 to 60 inches; mottled light olive brown (2.5Y 5/6), strong brown (7.5YR 4/6), and grayish brown (10YR 5/2) very cherty silty clay loam; brittle in place; chert-controlled structure; firm; thick clay flows along polygonal structure lines; about 60 percent chert fragments; extremely acid.

21. Depth to the fragipan ranges from 16 to 28 inches. In uncultivated areas the A horizon has chroma of 2 or 3. The content of chert in this horizon ranges from 0 to 5 percent. The BE horizon has hue of 10YR or 7.5YR and chroma of 4 to 6. It is silt loam or silty clay loam. The Bt horizon has hue of 10YR or 7.5YR and chroma of 4 to 8. The Bx horizon is mottled with hue of 7.5YR to 2.5YR and chroma of 2 or 8 and shades of gray and yellowish red. It is silt loam, silty clay loam, or the cherty or very cherty analogs of those textures. The content of chert in this horizon ranges from 10 to 60 percent.

24. Generalized Landscape Positions 1: Summit 2 and 3: Shoulder Slope 4 and 5: Backslope 6: Footslope 7: Toeslope Position helps understand relative Alluvial vs. Colluvial material deposition.

25. Slope Classes • 0 – 2% or 0 – 3% sometimes 0 – 6% A • 2 – 8% or 3 – 8% sometimes 2 – 6% B • 8 – 15% C • 15 – 25% sometimes 12 – 20% D • 25 – 35% sometimes 20 – 45% E • 35 – 60% F Designated by a A, B, C, D, E or F at the end of the Map Unit Symbol

26. Drainage Classes

27. Redox Features and Mottling in Relation to Drainage Classes • 0 – 6 in. very poorly drained • 6 – 12 in. poorly drained • 12 – 20 in. somewhat poorly drained • 20 – 32 in. moderately well drained • 32 – 42 in. well drained • 42 – 52 in. somewhat excessively well drained • > 52 in. excessively well drained

30. Soil Analysis • Physical analysis • Particle size • Moisture content • Bulk density • Available water capacity • Chemical analysis • Electrical conductivity • pH • Available NPK • Organic matter content

31. Physical Soil Analysis • Soil Particle size Analysis • Soil consists of discrete particles of various shapes and sizes. The object of a particle size analysis is to group these particles into separate ranges of sizes and so determine the relative proportion by weight of each size range. • The method employs sieving and sedimentation of a soil/water/dispersant suspension to separate the particles. The sedimentation technique is based on an application of Stokes‘ law to a soil/water suspension and periodic measurement of the density of the suspension. • Uses a soil hydrometer, graduated cylinders, a sieve, timer.

32. Physical Soil Analysis Soil texture – relative proportion of different grain sizes Of mineral particles in the soil. Sand, Silt, Clay

33. Physical Soil Analysis • Soil moisture content measurements (partial list) • Gravimetric. This involves collecting a sample, weighing it, drying it, and then reweighing it. • Porous resistance blocks. Can be calibrated to measure either content or potential. Their performance is only acceptable in relatively dry soil where the q - y relation is more or less linear. They are easy to use once calibrated, but are not particularly accurate • Neutron probes. Provide high accuracy and non-destructive testing, by measuring water content surrounding an access tube installed in the soil. Use is declining because of the health risk and legal reporting requirements. • Theta Probe -

34. Physical Soil Analysis • Bulk Density • The weight of a volume of bulk soil. Water is the standard by which other densities are compared. For water: 1 g/cc = 1 Mg/m3 = 1 kg/L http://soil.gsfc.nasa.gov/pvg/6-1inst.jpg

35. Physical Soil Analysis • Available water capacity • The range of available water that can be stored in soil and be available for growing crops.

36. Chemical Soil Analysis • 1954 to 1986 • NH4 Acetate by sequential Atomic Adsorption (AA) • K • CA • Mg • Na • Bray P1 by Spec 20 • P04 -P

37. Soil Analysis • 1997 to present • Mehlich-3 by simultaneous Inductively Coupled Argon Plasma Spectrophotometry (ICP-AE) • Ca, Mg, K, Na • Fe, Mn, Zn, Cu • B • PO4-P • SO4-S • 11 analyses every 60s

38. Soil Analysis • What is a good extractant? • Mimics a plant root. • Plant available nutrients released form the soil during the growing season • Good Procedure • Rapid • Inexpensive • Analysis are well correlated to crop nutrient response

39. Soil Analysis • Extactants • NH4 Acetate • Major nutrients • DTPA • Minor nutrients • Bray P1 • Phosphorus • Mehlich-3 (used in Arkansas soil testing lab) • All the above

40. Soil Analysis • Analytical Instrumentation • Spectrophotometer (Spec 20) • PO4-P • Bray P1 • Walkley-Black soil organic matter (Chromic Acid)

41. Soil Analysis • Analytical Instrumentation • Flame Atomic Adsorption (AA) • Ca, Mg, K, Na (NH4 Acetate) • Fe, Mn, Zn, Cu, (DTPA) • Acetylene flame

42. Soil Analysis • Analytical Instrumentation • Inductively Coupled Argon Plasma Spectrophotometry (ICP-AE) • Ca, Mg, K, Fe, Mn, Zn, Cu, B, P, S, (Mehlich-3) • Argon Carrier

43. Soil Analysis • Analytical Instrumentation • pH & Ionic Strength • Soils can be difficult • Buffer solution… high • Sample… low • Selective Ion Electrodes • 1:2 pH • NO3-N

44. Soil Analysis • Soil pH • Soil pH is a measure of hydrogen-ion (H+) activity in a soil suspension. This property influences the many aspects of crop production and soil chemistry, including availability of nutrients and toxic substances, activity and diversity of microbial populations, and activity of certain pesticides. Soil pH is defined as the negative logarithm (base 10) of the H+ activity (moles per liter) in the soil solution. As the activity of H+ in the soil solution increases, the soil pH value decreases. Soils with pH values below 7 are referred to as “acid”; pH values above 7 are referred to as “alkaline”; soils at pH 7 are referred to as “neutral”.  • Saturated paste used for testing pH • 1:1 • 1:2** • 1:5 • 1:10 • 0.01M CaCl2 • 1.0M KCl

45. Soil Analysis • Soil electrical conductivity • The purpose: To determine the concentrations of soluble salts. All soil has some water soluble salts which include essential nutrients for plants to grow. If the water soluble salts exceed an certain level then harmful effects on plant growth occur. The common unit of measurement for electrical conductivity is microsiemens/centimeter formerly micromhos/cm.

46. Soil Analysis • Soil Organic Matter • Total Organic Carbon • 900oC • Walkley-Black (Old) • Low heat chromic acid digest • Loss on Ignition (Old) • 450oC

47. Chemical Soil Analysis • Factors that Affect Analysis • Temperature • Extractant* • Shaking Time • Extraction Ratio* • Instrumentation* • Sample partial size • Technique • (The Soil Analysis information is from Bill Baker)

48. Soil Analysis • Arkansas Soil testing Lab • http://www.uark.edu/depts/soiltest/ • Understanding your soil test report • http://www.uaex.edu/Other_Areas/publications/PDF/FSA-2118.pdf

49. Example Exam Questions Other Example Quiz questions 1. What is the first GIS implementation Phase? 2. A _______ _______ defines a organizations purpose and forms the basis for defining tasks to be implemented by the organization 3. Name two examples of how you might identify and specify GIS user requirements. 4. Define Data Quality. 5. The ”level of data quality” should be balanced against the ________________________________. 6. _________ is the degree to which data agree with the values of the real-world features that they represent. 7. ___________ is a measure of “how exact data are measured and stored.”

50. Example Exam Questions 8. T of F. High precision always means high accuracy 9. List three types of errors. 10. What type of error refers to “mistakes”. They can be detected and avoided via well-designed and careful data collection. 11. What implies the lack of confidence in the use of the data due to incomplete knowledge of the data. 12. Name the five data quality components and be able to define them. 13. List and be able to describe Geographic Data Standards.