SOIL TEXTURE

Soil texture is the finess or coarseness of the soil

It is determined by the proportion of different sized minerals.

Farmer soil texture is directly related to the workability of how easy it is to plough.

soils are classified according to their behavior of how light and heavy the soil it is.

SOIL STRUCTURE

Refers to the arrangements of soil particles and spaces between them.

Importance of soil structure

Root growth- better access to nutrients and water

Water movements-affects how water moves through the soil.

Soil erosion-well structured soil and less to prone erosion.

Types of aggregates

Blocky

Columnar

Factors affecting aggregate formation

Climate-it can wet,dry and freeze

Activity of soil organisms-fungal cement the soil particles together.

Organic matter-humas has a binding effects

Tillage operation-farmers carry out ploughing,manuring and liming

Chemicals properties of soil

Plants required 17 essential nutrients elements

Macro nutrients- needed in large quantities

Micro nutrients-needed in small quantities.

Soil particle/soil nutrients

Ions that are positively charged are called cations.

Ions that are negatively charged are called anions.

Leaching -the process where water or another liquid dissolves.

Soil ph, measure of how alkaline a soil is on a scale from 0 to 14.

Most plants grows best in the form of 5.5

Soil acidity can be reduced by liming.

Availablity of soil water for crop use.

Soil water from rainfall or irrigation is needed for soil organisms.

Hydroscopic water is absorbed into the soil from atmosphere.

Gravitational water is temporary soil water results from prolonged infiltration from heavy rain.

Soil saturation water holding capacity reached its maximum.

Field capacity the optimum level of soil for plant growth.

Capillary water is water that is available to plant.

Temporary wilting-crops begin wilting in the day but regain at night.

Permanently wilting-where crops does not recover at night and can result in death.

Algae-simple photosynthesis organisms-blue,green algae can fix atmospheric nitrogen

Fungi-forming visible structure-important in human formation.

Photosynthesis-plants take carbon dioxide from the atmosphere and use it to manufacture sugar