What is a primary threat to tundra ecosystems?

The primary threat to tundra ecosystems is oil exploration and pollution. Tundra regions, characterized by their low temperatures, short growing seasons, and delicate ecosystems, are particularly vulnerable to human activities such as oil extraction. This kind of exploitation can lead to habitat destruction, soil degradation, and pollution from spills and waste byproducts.

Oil exploration not only disrupts the physical landscape but also risks contaminating the surrounding water bodies and soil, which can have devastating effects on the flora and fauna that rely on these habitats. The harsh conditions of the tundra mean that recovery from such pollution is often slow, further compounding the detrimental effects on this sensitive environment.

In contrast, rapid growth of plant species and increased rainfall do not typically threaten tundra ecosystems; in fact, the extreme conditions often limit plant growth and rainfall in these areas. Additionally, complex food chains exist as part of the ecological framework and are not inherently a threat; rather, they demonstrate the interdependence of species within the ecosystem. Thus, it's the invasive nature of oil exploration and the resultant pollution that pose the most significant risks to tundra ecosystems.