Tropical forest are very dense. (Give geographical reason)
Answers
Because existing tropical forests contains low density of species and and huge density of trees
The reason why the tropical forest are very dense:
You would probably have heard that most of the farmers failed to raise good yield while they cut down the trees and use the land that belongs to a tropical rain-forest once. This is not because of the poor soil; actually, tropical forest is certainly so dense because the soil is acidic and the trees and their roots are a little bit fond of acidity.
Apart from the soil the temperature in the tropical region and the moisture helps disintegrate the dead plants and animals in 8x speed than other regions. This helps the trees to have enough nutrients just above the soil thus restrict the tree routes to search for nutrients for a long time.
Frequent rain washes the decayed and decaying plants and animals more frequently. The forest floor has no vegetation except tall and dense trees because of less sunlight falling on the ground and more water clearing the ground.