"DIFFERENT RELEVANT PROPERTIES AND FUNCTIONS OF SOIL, AS WELL AS PROCESSES THAT TAKE PLACE IN SOIL, ARE MAINLY DETERMINED BY ITS STRUCTURE. PARTICLE SIZE DISTRIBUTION (PSD) AND THE GEOMETRICAL CONFIGURATION OF THE PORE SPACE PLAY A CRUCIAL ROLE IN THE STRUCTURAL DEFINITION OF SOILS. OUR FORMER RESEARCH PROJECTS HAVE BEEN CONCERNED WITH THE MODELLING AND MATHEMATICAL ANALYSIS OF THOSE TWO ATTRIBUTES OF SOILS. WE HAVE MADE USE OF NOVEL MATHEMATICAL TECHNIQUES AND ALSO OF STATE-OF-THE-ART TECHNOLOGY, AS CONFOCAL MICROSCOPY, X-RAY COMPUTER TOMOGRAPHY OR LASER DIFFRACTION, TO PROGRESS IN THE ANALYSIS AND SIMULATION OF THE STRUCTURE AND GEOMETRY OF SOILS. IN THE SAME SPIRIT, THIS RESEARCH PROPOSAL INTRODUCES NEW OBJECTIVES AND TECHNIQUES TO APPROACH THE QUESTION DESCRIBED ABOVE. ALSO, IT CONSIDERS A SIMILAR ANALYSIS OF OTHER FUNDAMENTAL FACTORS THAT DETERMINE THE FORMATION OF SOIL, NAMELY TOPOGRAPHY, LITHOLOGY, OR DRAINAGE NETWORK ARCHITECTURE THAT ARE RELATED WITH THE FORMER ONES. THE SPECIFIC OBJECTIVES OF THIS RESEARCH PROPOSAL ARE DESCRIBED NEXT WITHIN THE CORRESPONDING DIFFERENT LINES: 1) TO BUILD NEW DISTRIBUTIONAL MODELS THAT PROVIDE A BETTER APPROXIMATION OF PSD WITHIN DIFFERENT �FUNCTIONAL� SIZE RANGES, THAT IS, SIZE RANGES THAT ARE MOSTLY RESPONSIBE OF CERTAIN SOIL FUNCTIONS. IN PARTICULAR, THIS ENTAILS THE STUDY AND ANALYSIS OF PEDOTRANSFER FUNCTONS THAT ARE OBTAINED FROM THE PSD VIA NOVEL METHODS OF DATA MINING. 2) TO DESIGN AND IMPLEMENT GEOMETRIC MODELS OF SOILS AS A GRANULAR POROUS MEDIA IN ORDER TO DESCRIBE AND QUANTIFY THE INTERGRANULAR SPACE VIA PARTICLE PACKING ALGORITHMS WITH PSD AS AN INPUT. GENERATION OF MODELS ABLE OF PRODUCING SYNTHETIC REPLICAS OF A SOIL�S POROUS SPACE FROM PREDEFINED MORPHOLOGICAL FEATURES (POROSITY, SPHERICAL SURFACE OF THE PORE/SOLID INTEFACER, CONNECTIVITY, ETC.) 3) TO CHARACTERIZE THE HETEROGENEITY AND OTHER SCALING PROPERTIES OF THE DRAINAGE BASIN, TOPOGRAPHY, AND LITHOLOGY OF A SPECIFIC REGION, AND ALSO THE HORIZONTAL AND VERTICAL VARIABILITY/HETEROGENEITY OF SOIL PROPERTIES. IN PARTICULAR, THIS ENCOMPRISES THE STUDY OF THE INTERSCALE AND INTERPHASE SURROGATION/INTERACTION OF SIGNIFICANT HETEROGENEITY PARAMETERS. THIS IS ALSO RELATED WITH A METHODOLOGICAL STUDY OF SOIL FROM THE POINT OF VIEW OF THE SO-CALLED COMPLEX SYSTEMS. 4) TO STUDY HOW DIFFERENT FORMS OF SOIL TILLAGE AFFECT THE THE GEOMETRIC STRUCTURE OF SOIL POROUS SPACE. THIS REQUIRES THE ANALYSIS OF TOMOGRAPHY IMAGES OF SOIL AS WELL AS THE USE OF TECHNIQUES OF MATHEMATICAL MORPHOLOGY. "