This slide covers general topic of methodology of soil survey, soil evaluation and soil classification.

1. CHAPTER 4: Soil Survey,
classification and evaluation
4.1 SOIL SURVEY
•Introduction of Soil Survey
•Stages in Soil Survey Program
•Types of Soil Survey
•Steps in Soil Survey
•Land Capability Classification
4.2 SOIL CLASSIFACTION
•Soil Classification Systems
•Soil Classification Scheme
4.3 LAND EVALUATION

2. 4.1 SOIL SURVEY
Introduction to Soil Survey
• Soil Survey = the process of classifying soil
types and other soil properties in a given area
and geo-encoding such information
• published results of soil survey activities

3. Steps in Soil Survey Program
Stage 1: Pre-Field Activities
Stage 2: Field Survey
1. Soil Mapping
2. Evaluation and Field activities
Stage 3: Post-Field
Activities

4. Kinds of Soil Survey
• Reconnaissance Surveys
• Detailed Special Surveys
• Special Purpose Surveys

6. Step 1: Delineating Soil Unit
• Delineating soil unit with respect to
topography
• determination of texture
• Determination of slope – Erosion phases
• Vegetation

7. - video

10. Step 2: Soil Sampling
• 2 types:
• a) Free Survey
- As many as necessary samples are taken within
the boundaries
b) Grid Survey
- Transverses and transect s are laid out in a grid
pattern, samples are taken at every intersect.
Distance between lines: 50 meter
Draw both types of Surveys Maps

11. 3. Profile Sampling
• Profile pit is dug to C or R horizon
• 120 to 200 cm if regolith extend beyond 200
cm
• Pit size is enough for a person to go down and
turn around
• Expensive & Labour Intensive

13. • Use Core sampler
• Cheaper and easier

15. • Fill the profile description form

16. • Expressing the physical phases of soil
- Soil Texture
- Soil Structure
- Soil Consistence/Soil Strength
- Soil Color
- Soil Permeability
- Soil Temperature

17. Step 4: Plotting the Soil Mapping
Unit
• Collaborating analytical data are coded in
term of soil types, phases (stoniness and
erosion) and slope.

18. Step 5: Correlation
• Previous profile study
• if the profile under study indicates very close
similarities with an established profile existing
in another place the soil under study is name
after the other soil

19. Step 6: Soil Mapping
• Preparing scaled map showing all soil unit investigated

20. Step 7: Soil Survey Report
• The report embodies all items in the soil
survey program

21. Step 8: Land Capability Classification
• refers to the productive capacity of the soil for
intensive as influence by soil fertility, moisture
supply and depth of solum
• 2 main points land capability
a) soil limitation -soil physical aspect that restrict
crop production
b) climatic limitation - adverse climatic problem

24. QUESTIONS AND DISCUSSION?

25. 4.2 SOIL CLASSIFICATION
Introduction to Soil Classification
• grouping soils by their intrinsic property (soil
morphology), behavior, or genesis, results in classes
that can be interpreted for many diverse uses.
• No universally accepted classification system
• Based on field: Agriculture, Engineering, OSHA
• Lead to confusion
Most common for Agriculture :
US Soil Taxonomy (1975)
FAO/UNESCO Soil Classification (1974)

26. FAO Soil Classification
• first published in form of the UNESCO Soil
Map of the World (1974)
• Many of the names offered in that
classification are known in many countries
and do have similar meanings.
• Many countries modified this system to fit
their particular needs.
• Soil Units form 26 World Classes.
• intended for mapping soils at a continental
scale but not at local scale.

27. 26 Classes of Soil (FAO/UNESCO)
• Acrisols
• Andosols
• Arenosols
• Cambisols
• Chernozems
• Ferralsols
• Fluvisols
• Gleysols
• Greyzems
• Gypsisols
• Histosols
• Kastanozems
• Lithosols
• Luvisols
• Nitosols
• Phaeozems
• Planosols
• Podzols
• Podzoluvisols
• Rankers
• Regosols
• Rendzinas
• Solonchaks
• Solonetz
• Vertisols
• Yermosols

29. USDA Soil Taxonomy
• developed by United States Department of
Agriculture and the National Cooperative
Soil Survey provides an elaborate
classification of soil types according to
several parameters (most commonly their
properties) and in 7 levels; Order >>
Suborder >> Great Group >> Subgroup >>
Family >> Series.
• 12 orders

30. 12 Orders of Soils (USDA)
• alfisols
• aridisols
• gelisols
• inceptisols
• oxisols
• ultisols
• andisols
• entisols
• histosols
• mollisols
• spodosols
• vertisols

33. Example of USDA Taxonomy

35. 4.3 LAND EVALUATION
Introduction to Land Evaluation
• the process of valuing real property (usually
market value).
• requires appraisals because they occur
infrequently and every property is unique
(especially their location, a key factor in
valuation)
• Land Appraisal consists 2 phases: a) land
characterization b) socio-economy aspect

37. The End