Introduction

In this unit we will focus on:

• agricultural crops and their residues, and
• animal waste from livestock.

In farming communities, the main source of biomass is crops. The agricultural residue tends to be whatever is left on the fields after the crops have been harvested — for example, rice straw, wheat straw, rice husk and corn stalks and cobs. This residue can be used for fodder, as fill-up material in landfills (with a view to using the landfill for other purposes after it has been decommissioned) or as a heating fuel.

Forestry residue consists of branches, leaves, bark and other pieces of wood. This residue can be converted into fuel and fertiliser pellets.

The conversion of residues into useful products is an example of total biomass use.

Outcomes

Upon completion of this unit you will be able to:

• explain the link between human habitat, natural resources and optimal use of natural resources through total or near total biomass use.

Terminology

Manure:  Animal dung and waste used as fertiliser.

Livestock:  Domestic animals raised in farm settings to provide milk, eggs, meat, fur and leather for human consumption and use.

Fodder:  Food, especially dried hay or straw, for cattle and other livestock.

Fermentation:  The chemical breakdown of a substance by bacteria, yeasts or other micro-organisms.

Renewable energy:  Energy that comes from a source that can be reused indefinitely — for example, solar energy (from the sun), wind energy and geothermal heat.

Optimisation:  Making the best or most effective use of a resource.

By-products:  Something that is produced as a result of making something else — for example, buttermilk is a by-product of butter production.