CHAPTER 30.1Plant Nutrients and Availability in SoilAP BiologySpring 2011

THE REQUIRED NUTRIENTS

Sixteen essential elements are required for plant growth and survival

Macronutrients: used in significant quantities Nine elements C, H, O, N, K, Ca, Mg, P, S

Micronutrients: used in trace quantities Seven elements Cl, Fe, B, Mn, Z, Cu, Mb

THE REQUIRED NUTRIENTS

Deficiencies in any nutrient can visibly impact a plants health

PROPERTIES OF SOIL

Soil consists of particles of minerals mixed with humus Humus: dead organisms and their litter

Particles come in 3 sizes: Sand Silt Clay

PROPERTIES OF SOIL

Clay: the smallest, holds onto nutrients as water percolates through the soil

Loams: soils with nearly equal proportions of the three particle types Plants do best in loams

PROPERTIES OF SOIL

Layers of soil can be classified by profile properties Topsoil's: the

uppermost, is he most essential layer for plant growth

LEACHING AND EROSION

Leaching: removal of some nutrients from soil as water percolates through it

Erosion: movement of land under the force of wind, running water, and ice

The loss of topsoil can have a huge economic impact due to inability to grow crops