What is the first stage of primary succession often characterized by?

The first stage of primary succession is characterized by a barren landscape with no soil. This occurs in environments where there has been a significant disturbance, such as a volcanic eruption or glacial retreat, which results in exposed rock and sediment. In such conditions, the initial colonizers are typically pioneer species, such as lichens and mosses, which can survive in harsh environments and contribute to soil formation by breaking down the rock and accumulating organic material over time. This gradual process helps to create a more hospitable environment for subsequent stages of succession, where more complex plant species can eventually establish themselves.

The other options refer to later stages or scenarios that do not accurately describe the beginning of primary succession. Thus, the defining characteristic of primary succession's first stage as a barren landscape devoid of soil is essential for understanding ecological recovery processes.