Lecture 1 Introduction to Soils and Soil Ecosystem Services — Vocabulary Flashcards

Vocabulary flashcards covering key terms from the lecture on soils and ecosystem services, including soil definitions, soil profiles, soil functions, ecosystem services categories, and common forms of soil degradation.

Soil

The natural, unconsolidated mineral and organic material on Earth's surface that supports plant growth and hosts living organisms, formed by interaction of parent material, climate, organisms, and landscape.

Soil profile

A vertical section of soil through all horizons down to the parent material.

Soil horizon

A distinct layer within a soil profile formed by soil-forming processes.

Weathering

The breakdown of rocks, minerals, and organic matter that drives soil formation.

Soil formation

The slow, complex set of processes that transform parent material into soil, including destructive and synthetic steps.

Destructive processes (soil formation)

Soil-forming processes that break down materials (e.g., weathering, organic matter decomposition).

Synthetic processes (soil formation)

Soil-forming processes that create new minerals/organic matter and develop horizons.

Soils are _____ systems

Living

Soil biota

The living organisms in soil, from bacteria and fungi to earthworms and arthropods.

Ecosystem services

Benefits humans obtain from ecosystems, grouped into provisioning, regulating, cultural, and supporting services.

Provisioning services

Tangible products from ecosystems, e.g., food, water, fuel, fibre, biochemicals, and genetic resources.

Regulating services

Regulation of climate, floods, diseases, water quality, and pollination.

Cultural services

Non-material benefits from ecosystems, including recreation, aesthetics, inspiration, education, and sense of place.

Supporting services

Foundational ecological processes (e.g., soil formation, nutrient cycling, primary production) that enable other services.

Soil functions

Roles soils perform to support life, such as growth medium, water regulation, habitat, recycling, energy balance, and construction.

Global function: plant growth medium

Soil provides anchorage for roots and supplies water and nutrients to support plant growth.

Global function: regulate water supply

Soil absorbs, stores, and releases water, helping regulate river flows and water availability.

Global function: habitat for soil organisms

A tiny portion of soil hosts billions of microorganisms; many are ecosystem engineers.

Global function: nature’s recycling system

Soils and organisms recycle elements like carbon, nitrogen, and phosphorus from waste and dead matter for reuse.

Global function: global energy cycle

Soil modulates solar energy interactions and can store and re-radiate heat.

Global function: influences atmospheric conditions

Soils exchange gases (CO2, O2), drive evaporation, and influence dust and heat transfer.

Global function: engineering medium

Soils serve as construction materials for roads, dams, and foundations.

Soil degradation

Deterioration of soil quality or function due to pressures and processes, reducing ecosystem services.

Loss of topsoil

Removal or loss of fertile surface soil through water, wind, tillage, or overgrazing, increasing erosion risk.

Soil compaction

Compression from heavy use that reduces pore space, raises runoff, and limits root growth.

Nutrient mining

Removal of nutrients via harvest without replenishment, lowering soil fertility.

Loss of organic matter

Depletion of soil organic matter, reducing soil health and structure.

Salinization

Accumulation of soluble salts in soil that can cause plant toxicity and reduce productivity.

Contamination

Pollutants entering soil from spills or leaching, causing toxicity.

Soil health

The capacity of soil to function as a living system and support system services.

Soil complexity

Variation in soil properties across locations due to formation factors, with place-specific vulnerability.

Ecosystem

A dynamic network of plant, animal, and microbial communities interacting with the non-living environment.

3-D soil

Soil is three-dimensional; properties vary vertically and horizontally.