The main reason is logging in Thailand. The most logging is for business. For example, There are making paper, building houses, and illegal logging for sale. People who smuggle wood because they need to sell the wood to benefit themselves. Without planting by themselves. It is causing form flooding, landslides problems due to soil erosion. When the rain is coming. The water may come down from many mountains. Because the trees have absorbed water, It held the topsoil. It was like a weir to slow down. Before the water is reaching the community area. The trees are falling. It makes the wood expensive. People turned to smuggle wood because they do not pay to buy the logging of business for any purpose (Allen, 2017). It is a factor that causes a decline in the number of forests and creates a lot of intelligence.