The Phosphorous Cycle | AQA A-Level Environmental Science Revision | Primrose Kitten

Phosphorous cycle

The movement of phosphorous through the lithosphere, hydrosphere, and biosphere, involving processes such as erosion, absorption by plants, and decomposition.

Phosphate ions

Dissolved phosphorous found in the hydrosphere, essential for biological molecules and susceptible to leaching into water bodies. Inorganic.

Lithosphere

The Earth's crust and upper mantle, where phosphates are found in rocks and soil, with low solubility in water.

Biosphere

The regions of the Earth occupied by living organisms, where phosphorous is present in bones, DNA, and cell membranes.

Limiting factor

The element in shortest supply, with phosphorous being the most likely limiting factor for plant growth in soil due to its slow cycle and low solubility.

Erosion and weathering

Processes that release phosphorous from rocks and cause leaching into water bodies, contributing to the slow phosphorous cycle.

Sedimentation

The process of phosphorous sinking to the bottom of the ocean, forming new rocks, and potentially being released through uplift and erosion.

Leaching

The process of phosphorous moving from soil into water bodies.

Soil biota

Microorganisms like bacteria and fungi that decompose waste, releasing phosphorous back into the soil for plant re-absorption.

Soil pH

The acidity or alkalinity of soil, impacting the solubility of phosphate ions and the availability of phosphorous for plant absorption.

Eutrophication

The excessive growth of aquatic plants due to high phosphorous levels from human activities like fertilizer use, leading to oxygen depletion and negative environmental impacts.

Guano

Accumulation of seabird droppings rich in phosphorous, mined for the manufacture of inorganic fertilizers, contributing to accelerated phosphorous mobilization.

Mycorrhizal fungi

Fungi forming a symbiotic relationship with plant roots, enhancing phosphorous absorption and reducing the need for inorganic fertilizers.

Circular economy model

A sustainability concept promoting the recycling and reuse of products to reduce the need for mining and growth, inspired by biogeochemical cycles like phosphorous.