Grade 6 Agriculture Study Notes

Conservation of Resources

Soil, water, and wild animals are natural resources — things found in nature that all living things depend on. When these resources are lost or damaged, farming becomes harder and food becomes scarce.

Conservation means using and protecting resources carefully so they stay useful for us and for future generations.

What this strand covers

• Controlling soil erosion — stopping soil from being carried away by water
• Conserving water through seedbeds — using smart planting methods to hold moisture in the soil
• Conserving wild animals — keeping wild animals away from crops without harming them

What is Soil Erosion?

Soil is one of the most important natural resources. It supports the life of plants and animals and must be well conserved to increase food production and promote food security.

Soil erosion is the process by which soil is removed and carried away — mainly by water. The soil most at risk is the topsoil, the upper layer of the ground that holds the nutrients plants need to grow.

When rain falls on bare ground — ground with no plants or cover on it — water picks up loose soil particles and carries them away. Protecting topsoil is important because once it is lost, the land becomes less fertile and harder to farm.

The Four Types of Soil Erosion

There are four main types of soil erosion caused by water. Each type has its own appearance and conditions.

(a) Splash erosion, also known as raindrop erosion, occurs when raindrops fall on bare ground, removing soil particles and creating small depressions. It may not be easily noticed unless observed closely.

(b) Sheet erosion occurs when flowing water washes away loose topsoil in a thin, uniform layer. It is common in areas with little or no vegetation cover.

(c) Rill erosion occurs when water flows over a gentle slope, carrying away loose topsoil and leaving shallow and narrow channels. Rill erosion, if not controlled, can lead to gully erosion.

(d) Gully erosion occurs when moving water flows on the ground surface, leaving deep and wide channels. It occurs mostly on steep slopes where water flows at high speed.

Observing Erosion in Your Locality

Soil erosion is not just a textbook topic — it happens in real places around you. When you visit your school compound or neighbourhood, look carefully for signs of each type.

Signs to look for

• Splash erosion: small holes or scattered soil near building walls or under roof edges
• Sheet erosion: bare ground where the surface looks smoothed or paler — with no visible channels
• Rill erosion: narrow, shallow grooves running down a gentle slope
• Gully erosion: deep, wide trenches cutting through steep ground

Recording your observations

Take photographs of erosion you find. Print or share them with your teacher, then stick them into your portfolio with a short note describing: the location, what the ground looks like, and the type of erosion you think it is.

A portfolio is a personal collection of your photographs and notes. It helps you track your learning and share your findings with the class.

What is Splash Erosion?

Splash erosion, also known as raindrop erosion, occurs when raindrops fall on bare ground, removing soil particles and creating small depressions.

Three key facts about splash erosion:

• It may not be easily noticed unless observed closely — this makes it easy to overlook.
• It also occurs near buildings, where raindrops fall from iron sheet roofs and hit the bare ground directly below.
• It is the first stage in the erosion process — if not stopped, it leads to sheet, rill, and eventually gully erosion.

What is Rill Erosion?

Rill erosion occurs when water flows over a gentle slope, carrying away loose topsoil and leaving shallow and narrow channels called rills.

Two important facts about rill erosion:

• Rills are small channels formed as water flows down a hill slope.
• Rill erosion can develop into gully erosion if not controlled early enough. Gully erosion is common where heavy rainfall causes run-off to flow very fast, carrying heavy objects like rocks and trees.

Small rills can be repaired early by returning soil back into the channels using a spade or jembe — but only if caught in time.

What is Sheet Erosion?

Sheet erosion occurs when flowing water washes away loose topsoil in a thin, uniform layer across the surface. It is common in areas with little or no vegetation cover.

Two key facts to remember:

• It occurs on bare ground where there is no vegetation cover.
• It cannot be noticed easily — because soil is removed evenly with no channels or holes, a farmer may not realise it is happening until much topsoil is already gone.