Final answer:
Humans could not survive without soil due to its critical role in agriculture, water retention, and supporting helpful bacteria and other lifeforms. Soil also moderates environmental extremes, aiding in the survivability of ecosystems. Thus, soil is indispensable for sustained human existence.
Step-by-step explanation:
Humans have developed intricate dependencies on the soil for survival. Soil is essential for agriculture, which in turn provides the bulk of human food. Plants rely on soil not just for the physical support of their roots but also for water retention, nutrients, and a home to a vast community of helpful bacteria and other organisms that facilitate numerous ecological processes.
Soils store great quantities of water, thus extending the availability of this critical resource beyond periods of rainfall, and support a diversity of lifeforms. Without soil, ecosystems would not be as robust and food production would be severely limited. Such a scenario would force humans to find alternative means of survival that might not exist or be sustainable, further straining the planet's resources. Furthermore, soil acts as a buffer against erosion and flooding, mitigating environmental extremes. Without soil's moderating presence, living conditions on Earth would be vastly different and likely much harsher, posing significant challenges to human survival. Essentially, the well-being of human civilization has been inherently linked with our ability to preserve and appropriately manage the health of soils across the globe.