Soil Science and Carbon Sequestration

Soil Science and Carbon Sequestration is a critical field that investigates the capacity of soils to capture and store atmospheric carbon, thereby mitigating climate change. This discipline examines how agricultural and land management practices—such as no-till farming, cover cropping, and agroforestry—can enhance the amount of carbon stored as soil organic matter, effectively turning soils into a significant carbon sink. By studying the complex biogeochemical processes that govern the flow of carbon between the atmosphere, plants, and the ground, researchers in this area aim to develop strategies that not only reduce greenhouse gas concentrations but also improve soil health, fertility, and resilience within the broader Earth system.

1. Foundations of Soil Science
   1. Definition and Functions of Soil
      1. Definition of Soil
         1. Scientific Definition
         2. Soil as a Natural Body
         3. Distinction from Regolith and Sediment
      2. Medium for Plant Growth
         1. Physical Support for Roots
            1. Root Anchorage
            2. Structural Stability
         2. Supply of Water and Nutrients
            1. Water Availability
            2. Nutrient Storage and Release
            3. Ion Exchange Processes
         3. Gas Exchange for Roots
            1. Oxygen Supply
            2. Carbon Dioxide Removal
            3. Root Respiration Requirements
      3. Water Supply and Purification
         1. Water Retention and Movement
            1. Infiltration Processes
            2. Percolation and Drainage
            3. Capillary Action
         2. Filtration of Contaminants
            1. Physical Filtration
            2. Chemical Adsorption
            3. Biological Degradation
         3. Groundwater Recharge
            1. Aquifer Replenishment
            2. Water Table Dynamics
      4. Habitat for Organisms
         1. Diversity of Soil Organisms
            1. Species Richness
            2. Functional Diversity
            3. Spatial Distribution
         2. Soil Food Web Structure
            1. Primary Producers
            2. Primary Consumers
            3. Secondary Consumers
            4. Decomposers
      5. Engineering Medium
         1. Soil as a Construction Material
            1. Foundation Support
            2. Road Base Material
            3. Embankment Construction
         2. Soil Stability and Load-Bearing Capacity
            1. Shear Strength
            2. Compressibility
            3. Settlement Characteristics
      6. Modifier of the Atmosphere
         1. Gas Exchange Processes
            1. Soil-Atmosphere Interface
            2. Diffusion Mechanisms
         2. Influence on Greenhouse Gases
            1. Carbon Dioxide Flux
            2. Methane Production and Oxidation
            3. Nitrous Oxide Emissions
   2. Soil Formation (Pedogenesis)
      1. Factors of Soil Formation (CLORPT)
         1. Climate
            1. Temperature Effects
               1. Weathering Rates
               2. Biological Activity
               3. Freeze-Thaw Cycles
            2. Precipitation Patterns
               1. Leaching Intensity
               2. Seasonal Distribution
               3. Drought Stress
         2. Organisms (Biota)
            1. Influence of Plants
               1. Root Systems
               2. Litter Production
               3. Rhizosphere Effects
            2. Influence of Animals
               1. Burrowing Activities
               2. Organic Matter Mixing
               3. Nutrient Redistribution
            3. Microbial Activity
               1. Decomposition Processes
               2. Mineral Weathering
               3. Soil Aggregate Formation
         3. Relief (Topography)
            1. Slope and Aspect
               1. Erosion and Deposition
               2. Solar Radiation Exposure
               3. Water Flow Patterns
            2. Drainage Patterns
               1. Surface Runoff
               2. Subsurface Flow
               3. Waterlogging Conditions
         4. Parent Material
            1. Types of Parent Material
               1. Igneous Rocks
               2. Sedimentary Rocks
               3. Metamorphic Rocks
               4. Unconsolidated Sediments
            2. Weathering Processes
               1. Physical Weathering
               2. Chemical Weathering
               3. Biological Weathering
         5. Time
            1. Soil Development Stages
               1. Initial Stages
               2. Intermediate Development
               3. Mature Soils
            2. Rates of Soil Formation
               1. Factors Affecting Rate
               2. Chronosequence Studies
      2. Basic Soil Forming Processes
         1. Additions
            1. Organic Matter Inputs
               1. Plant Residues
               2. Animal Waste
               3. Microbial Biomass
            2. Deposition of Sediments
               1. Wind Deposition
               2. Water Deposition
               3. Gravitational Deposition
         2. Losses
            1. Erosion
               1. Surface Erosion
               2. Mass Wasting
               3. Chemical Erosion
            2. Leaching of Nutrients
               1. Cation Leaching
               2. Anion Movement
               3. Organic Matter Loss
         3. Translocations
            1. Movement of Clay, Salts, and Organic Matter
               1. Vertical Movement
               2. Lateral Movement
            2. Illuviation and Eluviation
               1. Clay Translocation
               2. Iron and Aluminum Movement
               3. Organic Matter Migration
         4. Transformations
            1. Weathering of Minerals
               1. Primary to Secondary Minerals
               2. Clay Mineral Formation
            2. Decomposition of Organic Matter
               1. Humification Processes
               2. Mineralization
   3. Soil Composition
      1. Mineral Matter
         1. Primary Minerals
            1. Quartz
            2. Feldspars
            3. Micas
            4. Ferromagnesian Minerals
         2. Secondary Minerals
            1. Clay Minerals
            2. Iron and Aluminum Oxides
            3. Carbonates
            4. Sulfates
      2. Organic Matter
         1. Living Biomass
            1. Plant Roots
            2. Soil Fauna
            3. Microorganisms
         2. Decomposed Residues
            1. Fresh Organic Matter
            2. Partially Decomposed Material
            3. Humus
      3. Water
         1. Soil Water Content
            1. Gravimetric Water Content
            2. Volumetric Water Content
         2. Water Holding Capacity
            1. Field Capacity
            2. Permanent Wilting Point
            3. Available Water Capacity
      4. Air
         1. Soil Aeration
            1. Air-Filled Porosity
            2. Gas Composition
         2. Gas Exchange
            1. Diffusion Rates
            2. Convective Flow
   4. Soil Physical Properties
      1. Soil Texture
         1. Sand
            1. Particle Size Range
            2. Types of Sand
         2. Silt
            1. Particle Size Range
            2. Properties and Behavior
         3. Clay
            1. Particle Size Range
            2. Surface Area and Activity
         4. Textural Classes
            1. Textural Triangle
            2. Field Determination Methods
      2. Soil Structure
         1. Types of Soil Aggregates
            1. Granular Structure
            2. Blocky Structure
            3. Platy Structure
            4. Prismatic Structure
         2. Aggregate Stability
            1. Wet Stability
            2. Dry Stability
            3. Factors Affecting Stability
      3. Bulk Density and Porosity
         1. Measurement of Bulk Density
            1. Core Method
            2. Excavation Method
         2. Total and Pore Space
            1. Calculation Methods
            2. Typical Values
         3. Macropores and Micropores
            1. Size Classifications
            2. Functional Differences
      4. Soil Color
         1. Munsell Color System
            1. Hue, Value, and Chroma
            2. Color Notation
         2. Indicators of Soil Processes
            1. Organic Matter Content
            2. Iron Oxidation States
            3. Drainage Conditions
      5. Soil Temperature
         1. Factors Affecting Soil Temperature
            1. Solar Radiation
            2. Air Temperature
            3. Soil Properties
         2. Effects on Biological Activity
            1. Microbial Activity
            2. Root Growth
            3. Nutrient Availability
   5. Soil Chemical Properties
      1. Soil pH
         1. Measurement and Scale
            1. pH Scale
            2. Measurement Methods
         2. Effects on Nutrient Availability
            1. Nutrient Solubility
            2. Microbial Activity
            3. Toxic Element Availability
      2. Cation Exchange Capacity (CEC)
         1. Definition and Importance
            1. Exchange Sites
            2. Nutrient Retention
         2. Factors Affecting CEC
            1. Clay Content
            2. Organic Matter
            3. pH Effects
      3. Nutrient Availability
         1. Macronutrients
            1. Nitrogen
            2. Phosphorus
            3. Potassium
            4. Calcium
            5. Magnesium
            6. Sulfur
         2. Micronutrients
            1. Iron
            2. Manganese
            3. Zinc
            4. Copper
            5. Boron
            6. Molybdenum
         3. Nutrient Cycling
            1. Mineralization
            2. Immobilization
            3. Plant Uptake
      4. Salinity and Sodicity
         1. Causes and Effects
            1. Salt Accumulation
            2. Sodium Effects
            3. Plant Responses
         2. Management Strategies
            1. Leaching
            2. Amendments
            3. Drainage Improvement
   6. Soil Biological Properties
      1. Soil Biota
         1. Macrofauna
            1. Earthworms
               1. Types and Distribution
               2. Ecological Functions
            2. Arthropods
               1. Insects
               2. Spiders
               3. Crustaceans
         2. Mesofauna
            1. Nematodes
               1. Feeding Groups
               2. Population Dynamics
            2. Microarthropods
               1. Collembola
               2. Mites
         3. Microfauna
            1. Protozoa
               1. Flagellates
               2. Amoebae
               3. Ciliates
         4. Microflora
            1. Bacteria
               1. Heterotrophic Bacteria
               2. Autotrophic Bacteria
            2. Fungi
               1. Saprophytic Fungi
               2. Mycorrhizal Fungi
            3. Actinomycetes
               1. Characteristics
               2. Functions
      2. Role of Soil Organisms in Nutrient Cycling
         1. Decomposition of Organic Matter
            1. Fragmentation
            2. Chemical Breakdown
            3. Mineralization
         2. Nitrogen Fixation
            1. Symbiotic Fixation
            2. Free-Living Fixers
         3. Mycorrhizal Associations
            1. Arbuscular Mycorrhizae
            2. Ectomycorrhizae
            3. Nutrient Exchange
         4. Disease Suppression
            1. Antagonistic Relationships
            2. Competition for Resources