What does the land lose as a result of soil erosion?

In desert and semi desert regions which of the following causes soil erosion?

Which of the following washes the soil off the hill slopes?

What is falling of trees in large numbers called?

Which of the following affected by soil erosion cannot produce enough to feed all the living beings who dwell on it?

Which is the upper most layer of earth?

Ploughing of which one of the following is yet another human factor that leads to soil erosion?

Which of the following causes flood?

The protection of soil against soil erosion is called:

The condition of  carrying away of soil by the action of water or wind is known as: