module 26, p1

Annual disturbance

Yearly plowing reverses succession and disrupts natural patterns.

Monocropping

Growing one crop species, reducing biodiversity and fragmenting habitats.

Plowing action

Deep soil turning that breaks structure and brings buried material to the surface.

A horizon turnover

Typical 15-20 cm soil layer flipped during plowing.

Row spacing

Even planting distances that reduce competition but are unnatural in ecosystems.

Tilling purpose

Soil preparation involving stirring, digging, and cultivating to manage weeds.

Rototilling

Walk-behind power tilling used in small gardens or small farms.

Soil aeration

Increased oxygen exposure from plowing and tilling that boosts nutrient availability.

Horizon mixing

Movement of organic matter downward and deeper nutrients upward.

CEC increase

Improved nutrient-holding ability due to mixing and organic matter relocation.

Base saturation rise

Greater presence of essential cations after soil turnover.

Wind erosion

Loss of loose soil and organic matter, raising particulate pollution.

Water erosion

Sediments washed into waterways, increasing turbidity and harming aquatic oxygen uptake.

CO₂ release

Decomposition of surface-exposed organic matter contributing greenhouse gases.

Plow layer

Human-created compacted horizon (Ap) from repeated disturbance.

Soil compaction

Reduced pore space from machinery or trampling, limiting infiltration and root growth.

Slash-and-burn

Clearing and burning forest vegetation to temporarily enrich nutrient-poor soils.

Shifting agriculture

Farming a plot for a few years before moving on due to nutrient depletion.

Ash nutrients

Potassium, calcium, and magnesium released during burning, raising soil fertility briefly.

Tropical leaching

Rapid rainfall removing nutrients and soil shortly after clearing.

Overuse pressure

Lack of recovery time causing long-term soil degradation and reduced productivity.

Fire emissions

Burning vegetation creating CO and particulates that worsen air quality.

Carbon spike

Net CO₂ increase when forests burn and trees no longer absorb carbon.

Brushland clearing

Historical burning in semiarid regions like California leading to permanent soil loss.

NPK ratio

Fertilizer labeling showing percent nitrogen, phosphorus, and potassium.

Synthetic fertilizer

Concentrated nutrients absorbed quickly by plants but prone to runoff pollution.

Organic fertilizer

Nutrient source containing decomposed matter that enhances soil CEC.

Nitrous oxide

Potent greenhouse gas released during nitrogen fertilizer production and use.

Eutrophication risk

Water nutrient overload from fertilizer runoff causing algal blooms and oxygen loss.