Native and non native species

This section connects to exercise 2 resistant trees, 4 it all starts from a seed, 7 Web of life, 10 habitat map, 13 (non)-native species

A habitat is the place or environment where a plant or animal naturally or normally lives and thrives. It provides the animal with food, water and shelter. There are many different sorts of habitats around the world from forests to grasslands and from mountain slopes to deserts all with their own distinctive characteristics. A city is a habitat that is home to many different animals, plants and people. A lot of them live very close to each other making the city a very special, always changing habitat. Some species do well in the altered and human managed habitats, while others are threatened due to decreased space, increased competition from other species, and changed water and sunlight conditions.

Not all trees are equally resistant to the changing environment. Some native species are experiencing difficulties to survive due to the changes in the climate they have been thriving in. At the same time, non-native species better suited for the new temperatures are finding their way into new territories often due to human activities (travelling, escaping from gardens…) and then thriving in new latitudes. This creates a threat to native forests as non-native species become invasive and start to overpower the competition for space. The forest’s character changes.

So why should we promote the native species if some non-native species do much better in the changing climate? Native species are less invasive, and therefore more conducive to biodiversity. Mostly they do better, i.e., are more resilient in the ecosystem in which they evolved in. They also add greater wildlife benefits, i.e., play a bigger role for the wildlife in the ecosystem for the other animals in it, be it through bearing fruit and nuts which can be eaten by species living in the same ecosystem, offering nesting spaces, etc.

Securing a diverse mix of species will maximise the benefits of trees. It will also help with conservation efforts such as insect and wildlife initiatives by providing more diverse habitats for more diverse species. In addition, species diversity ensures that an ecosystem, e.g., an urban forest, will be better prepared for pests and diseases which could wipe out an entire species of trees in one area and therefore cause severe changes in the wellbeing of all species within the ecosystem.