The last chapter of Lakes and Ponds deals with how human activities affect the natural ecosystems and their function through eutrophication, contamination, acidification, brownification and increases in UV radiation, and how such anthropogenic disturbances may affect biodiversity and the ability of organisms to utilize a specific habitat. In addition, the chapter addresses novel environmental threats, such as global climate change and effects from our everyday chemicals, such as contraceptives, nanoparticles and antidepressant drugs. However, also possibilities and signs of improvement are discussed, providing hope for coming generations.