One of the most interesting features seen in the study of the coastal environment is the wide variety of marine habitats. It is vital to examine both the physical and biological characteristics of a habitat to understand the presence and distribution of life forms there. The plants and animals that make their homes in any part of the ocean have special requirements for their survival and sustainability. In fact they often change their own habitats, modifying them in ways that affect themselves and other species.
From sandy beaches to rocky shores to mudflats to salt marshes, coastal marine habitats have very special and unique parameters that define them. Some of the most significant and measurable characteristics include the range of temperature, salinity, and dissolved oxygen. These in turn can be affected by the slope of the beach, the particle size of the sediments, and the exposure to waves and currents. In shallow areas such as bogs and estuaries an algae population bloom can have an important impact on dissolved oxygen (DO) levels, causing a sharp decrease in DO during decomposition and resulting in fish, mollusk, and crab declines.
Breaking waves can also have a major effect on the distribution of organisms. The weight of the water as it strikes the substrate will remove the smaller and lighter particles which can affect the amount of oxygen present. In order for animals to survive this dynamic and shifting environment they need to burrow deep into the ground or locate an object for attachment. Such turbulence along the shore can result in an eroded and constantly changing habitat.
Marine habitats on Cape Cod are also affected by nutrient loading, particularly nitrogen. Sources of nitrogen include septic systems, road runoff, lawn fertilizers, and atmospheric fallout from the burning of fossil fuels. This can lead to accelerated eutrophication of a shallow system and the algae blooms mentioned earlier.
Cape Cod is blessed with this diversity of marine habitats. There are several barrier beach systems in which salt marshes, estuaries, mud flats, sandy beaches, rocky shorelines, sand dunes, and salt ponds are present. Each of these microhabitats contains a specific assemblage of plants and animals interacting with one another and their physical environment. To fully understand the ecology of the shoreline one must carefully examine each of these habitats and discover the full range of species interactions.
Copyright Gil Newton 2009 Thanks to Chris Dumas for logo image.