Soil Science Module 1

Soil Science Module 1

• Soil components: Mineral matter, air, water, microorganisms, and organic matter
• Ideal soil proportions: 25% air, 25% water, 5% organic matter (SOM), 45% mineral matter
• Core soil properties: Texture, mineralogy, and organic matter
• Rock vs. mineral definitions: Minerals are solid, crystalline materials; rocks are naturally occurring mixtures of 2+ minerals
• Mechanical weathering: Breakdown of rocks into smaller pieces without changing chemical composition
• Biogeochemical weathering: Breakdown of rocks that changes chemical composition
• Soil separates and sizes: Sand (0.2-0.05mm), silt (0.05-0.002mm), clay(<0.002mm)
• Soil texture: The amount of each separate in a soil
• Soil texture impact: Influences water holding, decomposition rates, permeability, and the types of organisms that can live in the soil
• Specific surface area: Surface area per unit mass of soil particles
• Primary vs. secondary minerals: Primary minerals have little to no change in composition, secondary minerals form from breakdown and weathering of other minerals

Soil Science Module 2

• Common soil minerals: Iron oxides, calcium carbonates, sodium carbonates, clay minerals
• Importance of clay's negative charge: Attracts positive molecules, thus increasing water-holding capacity
• Soil organic matter formation: Breakdown of plant and animal matter by decomposers
• Soil organic matter impact: Influences water-holding capacity, plasticity, infiltration rate, nutrient content, soil fertility, diversity of organisms, and energy levels
• Agricultural management impact on SOM: Practices like tilling can decrease soil organic matter
• Physical soil characteristics impacting water: Soil texture and structure affect infiltration, permeability, and water holding capacity
• Soil structure types: Granular, blocky, prismatic, platy, massive
• Benefits of good soil structure: Reduced erosion, improved root penetration, increased water infiltration, and retention
• Bulk density: Mass of a unit volume of dry soil
• Soil porosity: Volume percentage of pores in a soil
• Relationship between bulk density and porosity: Inverse; higher density=lower porosity

Soil Science Module 3

• Soil formation factors: Parent material, topography, time, organisms, climate
• Parent material transport modes: Water (alluvial, lacustrine, marine), ice (glacial fluvial, glacial lacustrine, glacial till), wind (loess), gravity (colluvium)
• Soil textures of parent materials: Glacial advance (mix of sand, silt, and clay), glacial till (gravel and rock), glacial lacustrine (silt and clay), alluvium (sand, silt, and clay)
• Pedogenesis: Process of soil formation
• Pedogenic processes: Transformations (physical or chemical modification), translocations (lateral movement of materials), additions (inputs to soil), losses (loss from soil profile)
• Eluviation: Removal of dissolved or suspended material from soil layers by water movement

Soil Science Module 4

• Trophic levels in soil: Groups of organisms in an ecosystem that occupy the same level in a food web
• Metabolic strategies: Autotrophs (obtain carbon directly from CO2), heterotrophs (obtain carbon from preformed organic compounds), phototrophs (obtain energy from the sun), chemotrophs (obtain energy from inorganic elements or food)
• Major microorganisms: Bacteria, archaea, eukaryotes (animals, plants, protists, fungi)
• Rhizosphere: Soil zone influenced by plant roots
• Biological diversity: Different species present in the soil
• Functional diversity: Diversity of roles played by the soil community
• Soil functions delivered by soil biota: Decomposition, nutrient cycling, soil structure maintenance, primary producers/consumers

Soil Science Module 5

• Legume-rhizobium symbiosis: Biological nitrogen fixation (conversion of N2 to NH3)
• Arbuscular mycorrhizal-plant symbiosis: Fungi form a symbiotic relationship, increasing surface area for plants in exchange for carbon and nutrients
• Plant growth-promoting rhizobacteria (PGPR): Microorganisms that colonize the rhizosphere to enhance plant performance
• Essential nutrients: Macro- and micronutrients (C, H, O, N, K, Fe, Mn, Zn, etc.)—17 in total
• Criteria for essential nutrients: Necessary for a plant's life cycle, specific deficiencies, and directly involved in plant growth or metabolism
• Plant nutrient forms: N (NO3 and NH4), P (H2PO4, HPO4, and PO4), K (K)

Soil Science Module 6

• Nutrient uptake mechanisms: Diffusion, mass flow, root interception
• Liebig's Law of the Minimum: Crop growth is limited by the most scarce nutrient
• Nutrient cycling: Movement of elements within and between living and non-living parts of the ecosystem (driven by photosynthesis)
• N processes (inputs, transformations, losses): Nitrogen fixation, mineralization, immobilization, nitrification, denitrification, volatilization, leaching
• P processes (inputs, transformations, losses): Fixation, organic P mineralization, crop removal
• Importance of nutrient replenishment; Soil reserves and fertilizers

Soil Science Module 7

• Fertilizer definition: Natural or artificial substance containing nutrient elements to enhance plant growth
• Fertilizer grade: Analysis of chemical fertilizer expressed as percentages of total N, available P2O5, and soluble K2O
• 4Rs of nutrient management: Right source, right rate, right time, right place

Explore the foundational concepts of soil science in this quiz covering soil components, properties, and weathering processes. Test your understanding of soil texture, composition, and the differences between rocks and minerals. Ideal for students delving into soil studies and environmental science.