An ecological or environmental crises occurs when changes to the environment of a species or population destabilizes its continued survival. Some of the important causes include: Degradation of an abiotic ecological factor (for example, increase of temperature, less significant rainfalls) Increased pressures from predation Rise in the number of individuals (i.e. overpopulation) The evolutionary theory of punctuated equilibrium sees infrequent ecological crises as a potential driver of rapid evolution. Because of the impact of humans on the natural environment in the recent geological period, the term ecological crisis is often applied to environmental issues caused by human civilizations such as: the climate crisis, biodiversity loss and plastic pollution which have emerged as major global challenges during the first few decades of the 21st century. Climate change is starting to have major impacts on ecosystems. With global temperature rising, there is a decrease in snow-fall, and sea levels are rising. Ecosystems will change or evolve to cope with the increase in temperature. Consequently, many species are being driven out of their habitats. Polar bears are being threatened. They need ice for hunting seals, their primary prey. However, the ice caps are melting, making their hunting periods shorter each year. As a result, the polar bears are not developing enough fat for the winter; therefore, they are not able to reproduce at a healthy rate. Fresh water and wetland ecosystems are dealing with extreme effects of the increase of temperature. The climate change could be devastating to salmon and trout and to other aquatic life. The increase in temperature will disrupt the current life patterns of the salmon and trout. The cold-water fish will eventually leave their natural geographical range to live in cooler waters by migrating to higher elevations. While many species have been able to adapt to the new conditions by moving their range further towards the poles, other species are not as fortunate.
Paola Viganò, Sylvie Tram Nguyen, Qinyi Zhang
Paola Viganò, Elena Cogato Lanza, Anna Karla De Almeida Milani