2. Member States shall ensure that their contribution to fulfilling the commitment set out in paragraph 1 is achieved in full respect of ecological principles, including by ensuring species diversity and age-structure diversity, prioritising native tree species except for, in very specific cases and conditions, non-native species adapted to the local soil, climatic and ecological context and habitat conditions that play a role in fostering increased resilience to climate change. The measures to achieve that commitment shall aim to increase ecological connectivity and be based on sustainable afforestation, reforestation and tree planting and the increase of urban green space.