Deforestation is primarily caused by a combination of human activities and natural factors. Human activities, particularly agriculture, account for about 80% of global deforestation. The expansion of agricultural land, including subsistence farming and commercial agriculture, contributes significantly to deforestation. Other human-caused factors include infrastructure development (such as roads and dams), mining activities, and urbanization.

The effects of deforestation are far-reaching and have serious consequences for the environment and society. Here are some major effects:

1. Loss of Biodiversity: Deforestation leads to the destruction of natural habitats, resulting in the loss of numerous plant and animal species. Forests are incredibly biodiverse ecosystems, and their destruction threatens the survival of many species.

2. Climate Change: Trees absorb carbon dioxide, a greenhouse gas that contributes to climate change. Deforestation reduces the Earth's capacity for carbon sequestration, leading to increased greenhouse gas emissions and exacerbating global warming.

3. Disruption of Water Cycle: Forests play a crucial role in regulating the water cycle by absorbing rainfall and releasing it slowly into streams, rivers, and groundwater. Deforestation disrupts this cycle, leading to decreased water availability, increased soil erosion, and changes in local weather patterns.

4. Soil Erosion: The roots of trees help to bind and stabilize the soil, preventing erosion. When forests are cleared, the exposed soil is vulnerable to erosion by wind and rain, leading to nutrient depletion, decreased agricultural productivity, and sedimentation in water bodies.

5. Loss of Livelihoods: Forests provide livelihood opportunities for millions of people, including indigenous communities and local populations. Deforestation can result in the displacement and loss of livelihoods for these communities, leading to social and economic challenges.

6. Increased Flooding and Landslides: Forests act as natural buffers against floods and landslides by absorbing and retaining excess water. Deforestation reduces this capacity, increasing the risk of flooding and landslides in affected areas.

To address the causes and effects of deforestation, solutions like sustainable land management practices, reforestation and afforestation initiatives, responsible agriculture practices, and stricter regulations on logging and mining activities can be implemented. It is crucial to promote the conservation and sustainable use of forests to mitigate the adverse impacts of deforestation.