VISUAL SOIL EVALUATION
1 DESCRIBING SOIL STRUCTURES, ROOTING AND BIOLOGICAL ACTIVITY AND RECOGNIZING TILLAGE EFFECTS, DAMAGE AND RECOVERY IN CLAYEY AND SANDY SOILS 11 EVALUATION OF SOIL STRUCTURE 111 EVALUATION OF THE STRUCTURE OF CLAYEY SOILS 112 EVALUATION OF THE STRUCTURE OF SANDY SOILS 113 OBSERVATION OF THE STRUCTURE IN THE ENTIRE 06 OR 1 M OF THE PROFILE 114 SOILS WITH NATURAL STRUCTURAL LIMITATION 12 OBSERVATION OF ROOTS: DENSITY, DEFORMATION, CONCENTRATION IN CRACKS OR BETWEEN LAYERS 121 ROOT DEVELOPMENT IN CLAYEY SOILS 122 ROOT DEVELOPMENT IN SANDY SOILS 13 OTHER CRITERIA FOR RECOGNIZING COMPACTION 131 EVALUATION OF SOIL AERATION USING SOIL COLOUR 132 EVALUATION OF BIOLOGICAL ACTIVITY 14 CONCLUSIONS 2 ASSESSING STRUCTURAL QUALITY FOR CROP PERFORMANCE AND FOR AGRONOMY (VESS, VSA, SOILPAK, PROFIL CULTURAL, SUBVESS) 21 INTRODUCTION 22 VISUAL EVALUATION OF SOIL STRUCTURE (VESS) FOR TOPSOIL 23 VISUAL SOIL ASSESSMENT (VSA) FOR TOPSOIL 24 SOILPAK METHOD FOR TOPSOIL AND SUBSOIL 241 VALIDATION AND FUTURE DEVELOPMENT 25 ‘LE PROFIL CULTURAL’ OR AGRONOMIC PROFILE METHOD 251 LE PROFIL CULTURAL – EVALUATION AND LIMITATIONS CONTENTS 26 THE NUMERIC VISUAL EVALUATION OF SUBSOIL STRUCTURE (SUBVESS) 27 RECOMMENDATIONS 28 CONCLUSIONS 3 REDUCTION OF YIELD GAPS AND IMPROVEMENT OF ECOLOGICAL FUNCTION THROUGH LOCAL-TO-GLOBAL APPLICATIONS OF VISUAL SOIL ASSESSMENT 31 INTRODUCTION 32 YIELD GAP ANALYSIS 33 SOIL STRUCTURE ASSESSMENT USING VSE 34 SOIL STRUCTURE – ITS RELATIONSHIP WITH SOIL WATER STATUS AND HYDROLOGICAL CYCLES 35 LAND MANAGEMENT FRAMEWORKS RELATED TO SOIL PRODUCTIVITY, YIELD GAP ASSESSMENT AND ECOLOGICAL FUNCTION 351 FRAMEWORKS FOR AGRICULTURAL LAND MANAGEMENT LINKED WITH VSE TECHNIQUES AT FIELD SCALE 352 PACKAGES FOR LAND MANAGEMENT AT THE LANDSCAPE SCALE WITH POTENTIAL TO BE MORE EFFECTIVE IF INTER-LINKED WITH VSE TECHNIQUES 353 A POSSIBLE NEW AND BROAD CONCEPTUAL APPROACH FOR YIELD GAP REDUCTION AND ECOLOGICAL IMPROVEMENT BASED ON VSE TECHNIQUES 36 RELATING VISUALLY ASSESSED SOIL CONDITIONS TO CROP GROWTH AND SELECTION OF SOIL MANAGEMENT INPUTS 37 TRAINING OF PRACTITIONERS 38 CONCLUSIONS 4 VISUAL EVALUATION OF GRASSLAND AND ARABLE MANAGEMENT IMPACTS ON SOIL QUALITY 41 INTRODUCTION 42 EVALUATION OF ARABLE MANAGEMENT IMPACT 421 BIOLOGICAL FACTORS 422 MECHANICAL FACTORS 43 EVALUATION OF GRASSLAND MANAGEMENT IMPACT 431 BIOLOGICAL FACTORS 432 MECHANICAL IMPACTS 433 DRAINAGE/WATER STATUS 434 MANAGEMENT INTENSITY 44 ASPECTS REQUIRING FURTHER DEVELOPMENT 441 ASSESSMENT OF PORES 442 TAKING ACCOUNT OF SOIL LAYERING 443 EXTRACTION AND SEPARATION OF SOIL BLOCKS FOR ASSESSMENT 444 FAUNAL ACTIVITY 445 NEED FOR SPECIFIC METHODS OR INTERPRETATIONS FOR GRASSLAND SOILS 45 CONCLUSIONS 5 CHOOSING AND EVALUATING SOIL IMPROVEMENTS BY SUBSOILING AND COMPACTION CONTROL 51 INTRODUCTION 52 IDENTIFICATION OF COMPACTION PROBLEMS AND ALLEVIATION REQUIREMENTS 53 BASIC ACTION OF SOIL LOOSENING AND MOLE DRAINAGE EQUIPMENT 531 NARROW TINE DISTURBANCE AND CRITICAL DEPTH 532 WINGED TINE DISTURBANCE 533 LEG DISTURBANCE FOR SUBSOILING VS MOLING 54 SOIL DISTURBANCE WITH MULTIPLE TINE ARRANGEMENTS 55 DRAUGHT FORCES AND POWER REQUIREMENTS 56 IMPLEMENT SELECTION, ADJUSTMENT AND IN-FIELD EVALUATION 561 IMPLEMENT SELECTION 562 IMPLEMENT ADJUSTMENT 563 IN-FIELD EVALUATION 57 MINIMIZING AND ALLEVIATING RECOMPACTION 571 REDUCED WEIGHT AND INFLATION PRESSURE 572 CONTROLLED TRAFFIC FARMING 58 CONCLUSIONS 6 VALUING THE NEGLECTED: LESSONS AND METHODS FROM AN ORGANIC, ANTHROPIC SOIL SYSTEM IN THE OUTER HEBRIDES 61 INTRODUCTION 62 BACKGROUND 621 GEOLOGY, SLOPE AND RAINFALL 622 PHYSICAL STRUCTURE 623 MICROBIOLOGICAL PROCESSES 624 CULTIVATION 625 CROFTING: AN AGRICULTURAL AND SOCIAL SYSTEM 626 MAINTAINING SOIL FERTILITY WITHIN A MIXED SYSTEM 627 CURRENT SITUATION 63 TOOLS FOR VISUAL EVALUATION 631 METHODS 632 BLACKLAND INDEX 633 BLACKLAND VEGETATION SCORING (BVS) 634 VON POST HUMIFICATION SCALE 635 EVALUATION 64 RETURN TO USE 65 CONCLUSION 7 EVALUATING LAND QUALITY FOR CARBON STORAGE, GREENHOUSE GAS EMISSIONS AND NUTRIENT LEACHING 71 INTRODUCTION 72 SOIL PROPERTIES REGULATING CARBON STORAGE, GREENHOUSE GAS EMISSIONS AND NUTRIENT LEACHING AND THEIR RELATIONSHIP WITH SOIL STRUCTURE 721 SOIL CARBON STORAGE AND SOIL STRUCTURE 722 SOIL GREENHOUSE GAS EXCHANGE AND SOIL STRUCTURE 723 SOIL NUTRIENT LEACHING AND SOIL STRUCTURE 73 ESTIMATION OF SOIL C STORAGE, GHG EMISSIONS AND NUTRIENT LEACHING USING VISUAL TECHNIQUES 731 SOIL C STORAGE 732 GHG EMISSIONS 733 NUTRIENT LEACHING 74 FUTURE DIRECTIONS 75 CONCLUSIONS 8 SOIL STRUCTURE UNDER ADVERSE WEATHER/CLIMATE CONDITIONS 81 INTRODUCTION 82 CLIMATE CHANGE 83 SOIL STRUCTURE UNDER INTENSIVE RAINFALL 831 EROSION AND SOIL QUALITY SCREENING TOOLKIT 84 WET WEATHER CONDITIONS AND SOIL COMPACTION 85 PERIODS OF DROUGHTS 86 EXTREME TEMPERATURE 87 THE FURTHER ROLE OF VSE 88 CONCLUSION 9 THE EXPANDING DISCIPLINE AND ROLE OF VISUAL SOIL EVALUATION 91 INTRODUCTION 92 THE SCALE AND SCOPE OF VSE AND THE RELATIONSHIP WITH CROP YIELD 93 IMPROVING AND HARMONIZING VSE METHODS 94 EXPANDING THE ROLE OF VSE 941 SUSTAINABILITY, ENVIRONMENTAL CONSERVATION AND CLIMATE CHANGE 942 SOIL MONITORING AND RESILIENCE 943 IMPROVEMENT OF ARABLE AND GRASSLAND SOILS 944 IMPROVEMENT OF MARGINAL AND URBAN SOILS 945 SOIL SCIENCE 95 CONCLUSIONS SOIL COMPACTION AND EROSION HAVE EMERGED AS MAJOR THREATS TO GLOBAL AGRICULTURE AS THEY NEGA- TIVELY AFFECT PLANT PRODUCTION AND HAVE DETRIMEN- TAL IMPACTS ON THE ENVIRONMENT SOIL COMPACTION IS RESPONSIBLE FOR DECREASED CROP YIELD AND QUAL- ITY, EMISSIONS OF GREENHOUSE GASES AND INCREASED WATER RUNOFF (HAMZA AND ANDERSON, 2005; BALL ET AL, 2008) UNLESS SEVERE, IT IS OFTEN UNRECOG- NIZED BECAUSE PLANT GROWTH CAN APPEAR NORMAL, ESPECIALLY WHEN MINERAL FERTILIZERS ARE USED LIBER- ALLY THE MAJOR CROPPING FACTORS AFFECTING SOIL COMPACTION ARE THE WEIGHT OF MACHINERY, POOR TIMING OF FIELD OPERATIONS WITH RESPECT TO SOIL WATER CONTENT AND INTENSIFICATION OF CROP PRODUC- TION SOIL EROSION IS RESPONSIBLE FOR LOSSES OF SOIL PARTICLES, NUTRIENTS AND AGROCHEMICALS RESULTING IN DECREASED SOIL FERTILITY AS WELL AS EUTROPHICA- TION OF RIVERS AND LAKES (RASOULI ET AL, 2014) SITE CHARACTERISTICS (RAINFALL QUANTITY AND INTENSITY, SLOPE AND SOIL TEXTURE) HAVE STRONG EFFECTS ON SOIL EROSION; IN ADDITION, IMPORTANT CROPPING FACTORS RELATED TO SOIL EROSION ARE CROP ROTATION, PERCENTAGE SOIL COVER AND MANAGEMENT PRACTICES AFFECTING SOIL STRUCTURE AND COMPACTION (PIMENTEL ET AL, 1995; MORGAN, 2005) EROSION DEPOSITS ARE MOSTLY SILT AND FINE SAND WITH LITTLE STRUCTURE AND POROSITY AND THUS RESEMBLE SOIL DAMAGED BY COM- PACTION BECAUSE COMPACTION PLAYS A CENTRAL ROLE IN SOIL DEGRADATION AND YIELD LOSSES, IT HAS TO BE PROPERLY DIAGNOSED IN THE FIELD THIS CAN BE DONE BY OBSERVING SOIL STRUCTURE, ROOT DEVELOPMENT, AERATION AND EVIDENCE OF BIOLOGICAL ACTIVITY THIS CHAPTER WILL THEREFORE FOCUS ON DESCRIB- ING AND ILLUSTRATING IMPORTANT SOIL STRUCTURAL FEATURES ASSOCIATED WITH COMPACTION AND ANAER- OBIC CONDITIONS IT WILL COVER THE EVALUATION OF SOIL STRUCTURE AND COMPACTION STATUS FOR BOTH CLAYEY AND SANDY SOILS SINCE TILLAGE IS OFTEN RE- SPONSIBLE FOR THE CREATION OF A NUMBER OF AN- THROPIC LAYERS, EACH HAVING A DIFFERENT STRUCTURE, THE IDENTIFICATION OF THE DIFFERENT SOIL LAYERS WILL BE EXPLAINED THE USE OF OTHER INDICATORS OF SOIL COMPACTION SUCH AS ROOT DEVELOPMENT (DENSITY, DEFORMATION, CONCENTRATION IN CRACKS OR BETWEEN LAYERS), AERATION (SOIL COLOUR) AND BIOLOGICAL AC- TIVITY (SOIL MACROPOROSITY OF BIOLOGICAL ORIGIN, RAP- IDITY OF RESIDUE TURNOVER, PRESENCE OF EARTHWORMS) WILL ALSO BE COVERED 1 DESCRIBING SOIL STRUCTURES, ROOTING AND BIOLOGICAL ACTIVITY AND RECOGNIZING TILLAGE EFFECTS, DAMAGE AND RECOVERY IN CLAYEY AND SANDY SOILS