PedometricPedometric mappingmapping bridging the gaps between conventional and pedometric approaches SAMPLING - The chapter demonstrates how allocation of points in (a) N (b) the feature space influences the efficiency of prediction. It suggests how to represent spatial multivariate soil forming N environment; how to optimise sampling design for environmental DEM API correlation and which sampling strategies should be used for a SLOPE general soil survey purposes. EDOMETRIC PROFC PRE-PROCESSING - In this chapter, systematic methods for PLANC LAND USE reduction of errors (artefacts and outliers) in digital terrain CTI MAPPING parameters are suggested. These methods ensure more natural SINS (c) and more complete representation of the terrain morphology, AP bridging the gaps between conventional which then also reflects on the success of spatial prediction. AP_STD and pedometric approaches PHOTO-INTERPRETATION - This chapter suggests a semi-automated NDVI N method for extrapolating photo-interpretation from a limited number 0 2.5 km of study sub-areas to the whole area. The intention was to enhance and not to replace the mapper’s knowledge and expertise. Fig. 3. Multi-source predictors: (a) auxiliary predictors terrain parameters and remote sensing data; (b) aerial photo-interpreta- INTERPOLATION - This chapter considers the development of a tion map (API) and land use map and (c) location of the 59 soil flexible statistical framework for spatial prediction that should be profile observations. DEM – elevation; SLOPE – slope gradient in able to adopt both continuous and categorical soil variables. It %; PROFC – profile curvature; PLANC – plan curvature; CTI – suggests methods for dealing with non-normality of input data wetness index; SINS – slope insolation; AP – intensity of the and multicollinearity of predictors. aerial photo; AP_STD – standard deviation of the AP map and NDVI map derived from the Landsat 7 image. VISUALISATION - In this chapter, an algorithm is suggested to T. Hengl (a) SMU1 - CM_ce (67%), RG_ce (33%) visualize multiple memberships and to analyse geographical and SMU2 - CM_ce (50%), RG_ce (28%), CL_s (22%) thematic confusion. Multiple memberships are visualized using the SMU3 - CM_gc (83%), GL_ce (17%) Hue-Saturation-Intensity model and GIS calculations on colours. SMU4 - KS_cs (100%) SMU5 - KS_cs (100%) SMU6 - RG_ce (100%) The technological and theoretical advances in ORGANIZATION - This chapter collates methods from previous SMU7 - CM_ce (82%), GL_ce (9%), CL_s (9%) the last 20 years have lead to a number of new chapters and describes organizational structure of a hybrid grid- SMU8 - CM_ce (55%), KS_cs (27%), RG_ce (18%) SMU9 - CM_gc (50%), GL_ce (50%) methodological improvements in the field of based soil information system (SIS). It shows how to select a suitable soil mapping. Most of these belong to the grid size, how to aggregate and disaggregate soil information and (b)d) domain of the new emerging discipline – what are the advantages and disadvantages of a grid-based SIS. The CL_s pedometrics. Pedometric mapping is generally prediction maps were produced using both photo-interpretation and CM_ce characterised as a quantitative, (geo)statistical auxiliary maps, which ensures both continuous and crisp transitions. CM_gc production of soil geoinformation, also referred GL_ce to as the predictive or digital soil mapping. QUALITY CONTROL - In this chapter, systematic steps are KS_cs suggested to assess the effective scale, accuracy of soil bound- RG_ce Many new pedometric techniques such as sampling optimisation aries, accuracy of map legends, thematic purity of mapped (c) N entities and overlap among the adjacent entities. This assess- GL_ce algorithms, new interpolation techniques, fuzzy or continuous soil CM_gc maps are, however, still not fully applied in soil mapping at smaller, ment was based on a number of control surveys including control i.e. regional scales. The polygon-based soil maps with crisp profile observations and photo-interpretations. definition of soil classes are still used as the ‘state of the art’ KNOWLEDGE BANK KS_cs DESCRIBED AND (pedo-transfer functions, RG_ce MEASURED SOIL CLASSIFICATION PARAMETERS methodology. For a long time, the term pedometrics has been used classification systems - VARIABLES - class definitions (centers) soil types or suitability CL_s (profile data) as a challenge or contradiction of soil taxonomies, i.e. traditional classes) CM_ce systems. This thesis is an attempt to bridge the gaps between the 0 2.5 km INTERPOLATION PARAMETERS INTERPOLATE INTERPOLATED CLASSIFY USING SOIL CATEGORIES SOIL VARIABLES SOIL VARIABLES CONTINUOUS - regression coefficients (membership maps) empirical and automated methods and improve the practice of soil ON FINE GRID (raster maps) CLASSIFICATION - semivariogram parameters Fig. 4. Comparison of (a) the conventional soil map with mapping by designing an integrative pedometric methodology. The PREDICTORS: compound composition of mapping units, (b) defuzzified (highest) API, ENVIRONMENTAL thesis covers seven research papers/topics. VARIABLES, REMOTE SENSING IMAGES membership map from the supervised fuzzy k-means classifica- (raster maps) INFERENCE PARAMETERS RETRIEVE CLASIFFY - attribute tables tion with freely selected colours; (c) the continuous soil map with QUERY - parameters of the pedo-transfer TRANSFORM functions - suitability factor thresholds a circular legend and (d) down-scaled map to 100 m grid. CL_s – SAMPLING PRE-PROCESSING Siltic, Calcisols; CM_ce – Calcari-Eutric Cambisols; CM_gc – SOIL GEOINFORMATION (soil types, land Gleyi-Calcaric Cambisols; GL_ce – Calcari-Eutric Gleysols; KS_cs qualities, spatial PHOTO- queries) INTERPRETATION – Calci-Siltic Kastanozems and RG_ce – Calcari-Eutric Regosols. ? QUALITY c CONTROL a Fig. 2. Schematic flow of methodological steps used "A richly illustrated enthusiastic exposition of digital b within the hybrid grid-based Soil Information System. soil mapping... The author suffuses pedometrics in The proposed pedometric mapping methodology can be used to every syllable... Some of the non-idiomatic uses of a c b enhance the practice of soil mapping making the soil maps more English are very creative. 1.00 ORGANIZATION INTERPOLATION objective, detailed and more compatible for integration with other The particular strength of this thesis is that it defines 0.00 environmental geo-data. There is no need to use the concept of soil most or all of the aspects of pedometric mapping VISUALISATION mapping units or use double-crisp soil maps anymore. On the other EDOMETRIC Fig. 1. Schematic outline of the topics discussed in the hand, instead of abandoning photo-interpretation, soil classification that require attention... and tackles them!" thesis. Note the circular structure, which symbolizes that or empirical knowledge on soils, these methods can be successfully Alex B. McBratney, University of Sydney the soil maps need to be periodically updated. integrated with pedometric techniques. MAPPING Hengl, T. 2003. Pedometric mapping: bridging the gaps between For more information: the conventional and pedometric approaches. PhD thesis, bridging the gaps between conventional Wageningen University. Tomislav Hengl and pedometric approaches AGIS centre ITC Dissertation number 101, ITC, P.O. Box 6, 7500 AA Enschede, Faculty of Agriculture The Netherlands. Parts of the thesis are available on-line via the Trg Sv. Trojstva 3, ITC’s library website www.itc.nl/library/ 31000 Osijek, Croatia E-mail: [email protected] Home Page: http://www.pfos.hr/~hengl/ INTERNATIONAL INSTITUTE FOR GEO-INFORMATION SCIENCE AND EARTH OBSERVATION T. Hengl.