Dense forests are areas where trees grow very close together, creating a thick canopy that blocks sunlight from reaching the ground. These forests are often rich in biodiversity, providing habitats for many species of plants and animals. The layers of vegetation, including shrubs and underbrush, contribute to the complexity of the ecosystem. In dense forests, the variety of trees can include evergreens, deciduous trees, and tropical species, depending on the climate. These forests play a crucial role in regulating the Earth's climate, absorbing carbon dioxide and producing oxygen. They also help prevent soil erosion and maintain water cycles in the environment.