This document summarizes different types of terrestrial and aquatic ecosystems. Terrestrial ecosystems include forests, grasslands, and deserts. Forests are classified as Atlantic or Mediterranean based on climate. Grasslands are located in mountainous humid areas. Deserts and steppes are found in dry, extreme climate regions. Aquatic ecosystems can be marine or freshwater. Marine ecosystems include sandy beaches, rocky shores, and open sea, and are classified based on their salinity. Freshwater ecosystems include rivers and lagoons. The document also discusses threats to these ecosystems and ways governments protect the environment.