There are two other reasons for preserving biodiversity, both connected to global warming. First, when tropical rainforests are burned or cut, large amounts of carbon dioxide are released. This makes global warming worse. We need to keep biodiverse areas to keep our climate in balance. Second, as a result of climate change in the future caused by global warming, many food species will die. Food species diversity will be important for human food production in a changing environment. In fact, biodiversity may be crucial for providing plant species that can grow in different climates.