Lecture 13 Soil Fertility and Essential Nutrients

These flashcards cover key concepts related to soil fertility, essential nutrients, their functions, mechanisms of uptake, and the principles of nutrient cycling.

Soil fertility

The ability of the soil to supply essential nutrients to support plant growth and reproduction.

Essential nutrients

Nutrients necessary for plants to complete the vegetative or reproductive stages of their life cycle.

Liebig’s Law of the Minimum

Crop growth is dictated by the most limiting nutrient, not by the total amount available.

Nutrient cycling

The movement of elements within and between living (biotic) and non-living (abiotic) parts of the ecosystem.

Macronutrients

Nutrients required in relatively large quantities that make up the bulk of plant structural and protoplasmic tissue.

Micronutrients

Nutrients required in small amounts for enzymatic processes and other reactions.

Diffusion

A mechanism of nutrient uptake where nutrient concentration gradient drives nutrient movement.

Mass Flow

A mechanism of nutrient uptake where nutrients move with water driven by transpiration.

Root Interception

A mechanism of nutrient uptake where roots come into direct contact with nutrients in the soil.

Photosynthesis

The process by which plants harness solar energy to produce carbohydrates.

Deficiency symptoms of Nitrogen

Yellowing of older leaves, stunted growth, less tillering in cereals.

Deficiency symptoms of Phosphorus

Stunted growth, limited root development, purplish coloration of stems and leaves.

Deficiency symptoms of Potassium

Dull green leaves, yellowing of leaf edges.

Forms of Nitrogen used by plants

Nitrate (NO3-) and Ammonium (NH4+).

Energetic source of nutrient cycles

Photosynthesis is the energy source that drives nutrient cycling.