Crane beach is the first sandy habitat we visited, we chose this location because of its view of sand dunes. Crane's Beach is very large and plateau-like, with very little debris thanks to constant maintenance.
The sandy beach is one of the most rigorous habitats for organisms on Earth. The main reason is that the constantly shifting sand lacks any type of stability.
Sandy habitats are made up of loose rock particles of materials such as sand, gravel, shingle, pebbles or cobblestones or sometimes shells.
The movement of the ocean continually takes sand away from the beach and deposits it somewhere else. Winds move the sand around, and dunes act as a buffer between the ocean, the beach, and the inland areas.
In sandy habitats, like crane beach, sand is always changing. The wind causes ripples and waves in the sand causing constant movement.
Many people perceive the seafloor to be a smooth blanket of sand similar to a sandy beach. For some areas of the sea floor this is true.
Just as the sandy beach is flanked by rocky headland and muddy wetland, so are the smooth sandy plains of the sea floor flanked by various different substrates.
The sandy sea floor offers a habitat for a variety of species which include Giant Spider Crab, Atlantic Wolffish Pair, Fangtooth Fish, Six-Gill Shark, Giant Tube Worms, Vampire Squid, Pacific Viper fish.
The seafloor is often coated with several layers of sand, offering a variety of nutrients, minerals and potential habitats for creatures like this sand dollar.
Currents are generated by density differences in water masses caused by temperature and salinity variations. These currents move water masses through the deep ocean, taking nutrients, oxygen, and heat with them. This causes the sand on the sea floor to have trenches.
In physical geography, a dune is a hill of loose sand built by wind or the flow of water. Dunes occur in different shapes and sizes. Most dunes are formed by interaction with the flow of air or water.
Coastal dunes make up roughly one third of the Cape Cod National Seashore, covering approximately 8,500 acres from Chatham to Provincetown.
Plants near beaches need varying degrees of protection from wind and salt spray. If multiple dune ridges form, a maritime forest may grow. Under natural conditions, the types and density of vegetation are indicators of the age and length of stability of the dunes.
Sand dunes often contain plants and plant roots which help to keep its structure intact. They are part of the natural cycle of shore protection and the plants and animals that live on them contribute to this dynamic process.
The Dunes at crane beach had trails for the public to walk on so the class was able to walk through them and see different views of the dunes, and how the vegitation shifts.
Salt marshes serve as important nursery grounds and wildlife habitat. Animals and plants living beyond salt marsh borders also benefit from their productivity as tides carry nutrients and decayed plant materials from the marsh to surrounding areas, fueling other marine food webs.
Salt marshes are coastal wetlands that are flooded and drained by salt water. These low-lying vegetated wetlands are subject to the tides, with a distinct low marsh area and a high marsh area.
Much of the vegetation in salt marshes experiences periodic tidal flooding. Low and mid marsh areas can be submerged for hours, and high marshes can experience storm surge that can affect more upland vegetation.
Because salt marshes are frequently submerged by the tides and contain a lot of decomposing plant material, oxygen levels in the peat can be extremely low, know as hypoxia. This is caused by the growth of bacteria which produce the sulfurous rotten-egg smell that is often associated with marshes and mud flats.
Salt marshes also protect shorelines from erosion by buffering wave action and trapping sediments. They reduce flooding by slowing and absorbing rainwater and protect water quality by filtering runoff, and by metabolizing excess nutrients.