A sand dune ecosystem is a unique environment formed by the accumulation of sand, typically found along coastlines and in deserts. These ecosystems are characterized by shifting sands, which create a dynamic landscape that supports specialized plant and animal species. Common vegetation includes grasses and shrubs that have adapted to withstand harsh conditions, such as strong winds and limited water. The fauna in sand dune ecosystems includes various insects, birds, and small mammals that have evolved to thrive in this habitat. These organisms play essential roles in maintaining the ecosystem's balance, contributing to processes like pollination and seed dispersal. Overall, sand dune ecosystems are vital for biodiversity and serve as natural barriers against coastal erosion.