Final answer:
Vernal pools are seasonal wetlands that form in the spring and often dry up by summer. They lack fish, allowing for specialized amphibians and invertebrates to thrive, and feature hydrophytic vegetation and hydric soils. These pools are critical for biodiversity and contribute to the ecological health of the region.
Step-by-step explanation:
Vernal pools are a type of wetland characterized by being temporary, seasonal bodies of water. They typically form in the spring from melting snow and rainfall, and often dry up by summer. What is unique about vernal pools is that they lack fish, which allows for the development and survival of certain amphibian and invertebrate species that would otherwise fall prey to fish. The temporary nature of vernal pools means that many plants and animals have adapted to the unique seasonal cycle of flooding and drying.
For example, species such as the wood frog, spotted salamander, and fairy shrimp have highly specialized life cycles that coincide with the presence of these pools. Vernal pools are also known for their hydrophytic vegetation, which are plants adapted to grow in water-saturated soil. The soil of vernal pools is often hydric, meaning it is typically saturated and low in oxygen, influencing the types of plant life that can survive there.
The characteristics of vernal pools are essential for biodiversity, providing critical breeding habitats for many species. These pools contribute to the ecological health of the overall region, including nearby wetlands such as freshwater marshes, swamps, bogs, mudflats, and salt marshes. All these types of wetlands share hydrology, hydrophytic vegetation, and hydric soils as common features, but each has distinct characteristics and roles in the environment.