Title FO Unit 18 corrected.pdf ✅

determine the substrate composition (e.g., boulders, gravel, sand) and the morphology of the channel (e.g., pools, riffles). These physical characteristics create a diverse array of microhabitats that support specialized fauna. Lotic systems are home to numerous species of insects adapted to high-flow conditions, such as mayflies and stoneflies, as well as fish species like trout, eel, and minnow that possess streamlined bodies and behavioral adaptations to maintain their position in the current. Mammals such as beavers and otters are also integral components of these ecosystems. Wetlands Wetlands are distinct semi-aquatic ecosystems where the soil is saturated or inundated with water, either permanently or seasonally. This prolonged saturation results in oxygen-poor (anoxic) soil processes, which defines the unique vegetation and animal life found within them. Wetlands, which include marshes, swamps, and bogs, are recognized for their exceptionally high biodiversity and productivity, serving as critical habitats for a wide variety of plants, animals, and microbes. Marine Ecosystems Marine ecosystems are the largest of Earth's aquatic systems, covering approximately two-thirds of the planet's surface and existing in waters with a high salt content. Their vastness and complexity necessitate a classification based on depth and proximity to the shoreline. Zonation Marine habitats can be divided into several distinct zones. The oceanic zone represents the vast open part of the ocean, which is home to large, migratory species such as whales, sharks, and tuna. The benthic zone consists of the substrate below the water column, from the shallow continental shelves to the abyssal plains, and supports a diverse community of invertebrates. The intertidal zone is the dynamic area between high and low tides, subject to extreme fluctuations in temperature, salinity, and moisture. Coastal Ecosystems Where the land meets the ocean, marine coastal ecosystems form. These habitats, extending to the margins of the continental shelves, are characterized by exceptionally high levels of biodiversity and productivity. They encompass a wide array of distinct habitat types, each with its own species composition. Key coastal habitats include: ● Mangrove forests and salt marshes: These vegetated intertidal habitats provide critical nursery grounds and shelter for juvenile fish and invertebrates. ● Seagrass meadows and kelp forests: These underwater "forests" are highly productive and provide complex three-dimensional structures that serve as food and shelter for a multitude of species.