Step 1: Recall the hazard groups.
Hazards are sorted by their cause into geological, water and climatic, biological, and environmental hazards.
Step 2: Place a few examples.
Earthquakes and landslides are geological, floods and cyclones are water and climatic, and epidemics are biological.
Step 3: Look at deforestation.
Cutting down forests damages the natural surroundings and the balance of the environment over time.
Step 4: Pick its group.
Such damage to the surroundings is classed as an environmental hazard.
Step 5: Rule out the others.
It is not a sudden earth movement, not a weather event, and not a disease outbreak.
Step 6: Conclude.
Deforestation comes under environmental hazards.
\[ \boxed{\text{Environmental hazards}} \]