Thank you for viewing this post as it is about to be full of interesting tidbits.
To start off, all ecosystems are important in a variety of ways from the microscopic detritus communities to the expansive and diverse coral reef. Their function as a community varies as much as the settings they are found in. This complements the ongoing list of organisms that live there and the vital role that they play.
Detritus
In detritus communities usually found in areas with high organic material make home for a multitude of microscopic organisms that specialize in decomposing materials. Near mangrove communities for example, their role is to break down harder to eat substrates such as leaves and twigs in order to facilitate easier digestion for higher organisms. You can even find leaves in every stage of the decomposition process where color and texture can change dramatically from green to black and smooth to leathery. Not only do they assist in providing digestable vegetation, they themselves are eaten along with it for added nutrition. By examining even a small amount of detritus it is very clear that there is more that lives underfoot than anyone would care to think about. These areas are also important for a certain kinds of organisms called nitrogen fixers. The organisms break down the naturally produced ammonia in the form of urea and through many chemical processes turn it into usable nitrogen for all the plant communities to thrive on. Without these organisms there would not be enough usable nitrogen (which is a limiting nutrient for marine plants) for aquatic plants to survive in such numbers.
Open Oceans
How i see it the open ocean is entirely different than any of the other ecosystems, can you guess why? If you said because there are not any trees then you're right. So, where does the beginning of the food chain start if you have a lack of vegetation? Plankton, small and simple. There is a massive variety of smelly, microscopic plankton out there (Trust us it smells....pretty bad too.), and these organisms are responsible for almost all of the primary production of the open ocean. There are some seaweeds and floating alga that are out there but the majority of that bottom block of the food web is plankton. From there smaller fish eat the plankton and bigger fish eat them. In the open ocean there is no place to hide, so organisms that live there have adapted by various forms of morphology and pattern. The most prominent adaptation is coloring and specifically countershading. Animals that exhibit countershading are usually darker on their dorsal side so predators are less likely to see them from above and lighter on their ventral side to blend in more to predators in the deep. Their morphologies are based on who is the fastest. Fish in the open ocean tend to become more streamlined and aquadynamic to allow them to chase down their prey since adaptations are more likely to focus on the ability to outrun predators.
Sea Grass Beds
Seagrasses are a vital part of shallow water communities because of their functions. First they provide shelter to juvenilles that live there. Second, they can increase water clarity. They do this mainly by growing and blocking particles of sediment that are passing by which accounts for the fact they are usually surrounded by soft substrate mounds. They are also the main primary producers of their ecosystem which makes them the building block of the food web. Unfortunately, sea grasses are not very good at surviving deeper water or very turbid waters. This is because they need more sunlight than algae or corals, so typically you will find them where they can be seen from the surface. One of the problems that comes with sea grass is that boats can tear them up and disturb those ecosystems. Sea grass does not grow very fast and once damage has been done it takes a long time to rebuild. They also provide (unwillingly) habitat to epiphytes which grow on the surface of their blades and with enough of them can smother and kill the sea grass. Mind you that sea grass is the favorite food of some turtles and manatee, and you don't want to see them all die, so don't destroy the sea grass beds!
Coral Reefs
Coral reefs are the most diverse ecosystem of our adventures. Their zooxanthellae are the primary producers of the ecostystem and provide the color for the coral . The corals polyps make calcium carbonate skeletons that become the structure of the colony. They feed by harvesting energy from the zooxanthellae's photosynthesis or by using their tentacles to gather drifting food particles. They are very delicate and take a long time to grow. As they grow they provide shelter for a plethora of fishes, rays, sharks, and more. That makes coral one of the most important ecosystem engineers. It's because these organisms have such an effect on their ecosystem that every organism flocks to it. This includes people who want to see and touch the reefs and then take some with them. There are also other functions that coral reefs provide such as wave breakers which during a storm they take some of the energy out of the waves before they reach the shore. They are also key components of water clarity, as they block floating particles from out of the water column.
Overall this has been an amazing experience that I feel we will all remember as we were the first to partake in this class. Thank you all who gave us an opportunity to explore so many places and learn so much in five weeks. I can't wait to see how it will be done next year!
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