The human activities the no. 1 factor that can affect the ecosystem. The cleaning out of trees in the forest. "Deforestation"As a result of landslide, flood, lose of habitat , erosion, . The fish killing distract the organisms living in the water. Human activities such as dynamite fishing, and moro ami fishing will be lead to the destruction of coral reefs, the presence of pollutants caused by human activities such as global warming the temperature of the earth rise caused by green house effect because of too much accumulating of carbon dioxide , and especially the over population greatest factor that affect the environment result of shortage of food, space, water and fossil fuel ....