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Course:
NATURE,
PROPERTIES
ECOSYSTEMS
AND
CONSERVATION
OF
SOIL
Credits: 6 CFU
Professor: Fabrizio De Cesare
COURSE PROGRAMME
PART 1
SOIL AS AN INTEGRATED SYSTEM
 Soil as a continuously evolving heterogeneous system: definitions and concepts
 Soil components
 Solid fraction (mineral and organic): Mineral fraction (composition and features).
Organic fraction (origin of soil organic matter, biotic and abiotic components,
macromolecular and molecular constituents). Humic substances and their features.
Pedogenesis and its factors. Mineral weathering: causes of weathering; mineral
stability; products of mineral weathering; neogenesis; theories and processes of
mineral weathering. Humification: abiotic and biotic processes driving
transformation of organic matter; degradation, mineralisation and immobilisation;
reactions involved in humification; theories of humification processes.
 Water fraction: Soil-Water relationships: interactions between water and soil
constituents, influence on the biotic components and on the biotic and abiotic
processes in soil. Soil water potential and its components; soil water content;
water infiltration and retention; leaching; evaporation; runoff; field capacity;
wilting point; ionic composition of the soil solution.
 Gaseous fraction: Components of the gaseous fraction; influence on the metabolic
activity of various soil organisms and on soil redox potential.
 Biotic fraction: Soil animals (pedofauna): mega-, macro-, meso- and microfauna.
Soil flora (pedoflora): macro- (plant organisms - roots) and microflora. Soil
microorganisms: characteristics and localisation.
PART II
SOIL PROPERTIES
 Physical properties: soil texture; density; porosity; colour; temperature.
 Physicochemical properties: Permanent and variable charge; charge density and
electric double layer theories; ion exchange reactions and isotherms (adsorption);
cation exchange capacity; soil base saturation; anionic adsorption (negative,
positive, unspecific, phosphate adsorption – chemisorption).
 Chemical properties: Acidic soils: origin of acidity; the chemistry of Al;
processes of soil acidification; factors affecting plant growth in acidic soils;
phosphate and microelements availability in acidic soils; correction of soil acidity.
Alkaline soils (saline, saline-sodic, sodic): determination of salinity; alkalinisation
processes; physicochemical properties; influence on plant growth; correction of
alkaline soils. Soil pH: definition, measurement, actual and potential acidity. Soil as
a buffer system. Soil redox potential: oxidation reduction reactions; values of
redox potential in soil; examples of reactions in soil; redox potential and pH;
effect on nutrient availability and living organisms.
 Biological properties: The biogeochemical cycles; fluxes of nutrients and food
web and food chain; Interactions among microbial populations and other soil
organisms. Soil-plant ecosystem: the rhizosphere, its features and dynamics
(rhizosphere vs. bulk soil). Soil enzymes: origin, localisation, stability and kinetic
properties; role of soil enzymes in microbial and plant nutrition and in the global
nutrient cycles. Effects of soil organisms on soil formation (pedogenesis) and its
physical, chemical and physicochemical properties.
 Soil as an aggregate system (structure): Soil colloids. Relationship between
mineral and organic fractions. Soil structure formation and various levels of
structure (micro- and macroaggregates). Morphological classification of
aggregates. Role of soil oragnisms in soil structure.
PART III
ALTERATION AND CONSERVATION OF SOIL ECOSYSTEMS
 Alteration of soil ecosystems: Natural and anthropic perturbations: evolution of
soil management over centuries (intensive farming: intensive agricultural practices
and intensive animal farming practices – livestock), soil exploitation, degradation,
contamination and soil erosion. Soil as destination for municipal and industrial
waste disposal.
 Soil contamination and pollution: Contamination vs. pollution. Features of soil
pollution. Sources of soil contamination and pollution: industrial and agricultural
activities and waste disposal (landfill). Classes of soil contaminants and pollutants:
heavy metals, organic xenobiotics, acid rains. Properties of contaminants:
chemical, physical and physicochemical features; availability and toxicity. Fate of
contaminants in soil: physical, chemical, physicochemical and biological-biochemical
processes; degradation and persistence.
 Soil erosion: wind erosion and runoff; physical, chemical and biological factors of
erosion; consequence of erosion.
 Soil status monitoring and conservation: Soil quality, health and resilience and
soil management sustainability. Indicators of soil quality and health: soil erosion,
bioindicators and indices of quality and health. Recycling of biomasses and
remediation of polluted soils.
 Recycling biomasses in soil: Recycling and reuse of biomasses in agriculture
(compost, sludges, digestate, municipal wastes, etc.) and possible harmful
consequences.
 Remediation of polluted soils: Principles, techniques and technologies of
remediation (in situ and ex situ). Containment of polluted sites. Physical, chemical,
physicochemical and biological remediation processes (thermo-destruction,
thermal and chemical desorption, soil washing, vapour extraction, permeable
reactive barriers, immobilisation, dahalogenation, bioremediation, bioventing,
phytoremediation, etc.), and integrated approaches.
 Environmental monitoring: Monitoring of perturbed soil ecosystems through
various approaches: indirect and direct indicators; qualitative and quantitative
approaches; bioindicators (metabolic activity, biodiversity, fertility, etc.). Sensing
systems and devices.