ISA Certified Arborist Practice Exam

What is the impact of urbanization on tree populations?

1. It leads to increased biodiversity

2. It causes habitat loss and increased stress for trees

3. It has no impact on tree populations

4. It promotes tree planting initiatives

The correct answer is: It causes habitat loss and increased stress for trees

Urbanization significantly impacts tree populations primarily by causing habitat loss and increasing stress for trees. As cities expand, natural habitats are often cleared to make way for infrastructure, housing, and commercial development. This alteration drastically reduces the available space for trees to grow, thereby impacting not just their population density but also the overall biodiversity of the area. Moreover, urban environments present various stress factors for trees, such as soil compaction, pollution, limited root space, and altered water drainage patterns. These conditions can hinder tree growth, making them more susceptible to diseases, pests, and environmental stresses like drought or flooding. The cumulative effect of these stressors can lead to a decline in health and survival rates among urban tree populations. Urbanization does not typically lead to increased biodiversity due to the fragmentation of habitats and the dominance of non-native species, nor does it have no impact on tree populations. While some urban areas may undertake tree planting initiatives, these efforts are often insufficient to offset the overall negative impacts of urban development on existing tree populations.