Sebastian's+Ecosystem+Project

=Marine Biome= toc

A biome is a large geographical land with many similar ecosystems in it. The Marine biome covers about three-fourths of the Earth's surface which includes oceans, coral reefs, and estuaries. The plants in the biome such as algae supply much of the world's oxygen supply and take in a huge amount of carbon dioxide. The ocean is the largest of all the ecosystems. The ocean is separated into 4 different zones: intertidal, pelagic, abyssal, and benthic. All four zones have a great diversity of species.

The first zone, the intertidal zone, is where the ocean meets the land. Because of the area, the communities are constantly changing. Where only the highest tides reach, there are only a few species of algae and mollusks. In those areas usually submerged during high tide, there is a more diverse array of algae and small animals, such as herbivorous snails, crabs, sea stars, and small fishes. At the bottom of the intertidal zone, many invertebrates, fishes, and seaweed can be found. The fauna is worms, clams, predatory crustaceans, crabs, and shorebirds.

The second zone, the pelagic zone is the open ocean. The pelagic zone is generally cold though it is hard to give a general temperature. The flora in the pelagic zone includes surface seaweeds. The fauna include many species of fish and some mammals, such as whales and dolphins. They all feed on the great amount of plankton.

The third zone, the benthic zone, is the area below the pelagic zone. The bottom of the zone has a lot of sand and dead organisms. The temperature decreases as depth increases. The flora is mainly seaweed while the fauna is mostly bacteria, fungi, sponges, sea anemones, worms, sea stars, and fishes.

The last zone is the abyssal zone. The water in this region is very cold usually around 3° C. The abyssal zone supports many species of invertebrates and fishes. Special parts of the ocean are the coral reefs which are widely distributed in warm shallow waters. They can be found as barriers along continents such as the great barrier reef. The dominant organisms in coral reefs are corals. The fauna is mainly several species of microorganisms, invertebrates, fishes, sea urchins, and octopuses.

Estuaries are areas where freshwater streams or rivers merge with the ocean. This mixing of waters with different salt amounts creates a very interesting ecosystem. Micro flora like algae, and macro flora, such as seaweeds, and marsh grasses can be found here. Estuaries support a variety fauna such as worms, oysters, crabs, and waterfowl. =**Lake Muskoka**= Lake Muskoka is found in between Gravenhurst and Port Carling, Ontario. The lake water mostly comes from Lake Rosseau, the Muskoka River and Lake Joseph. There are many cottages that surround the lake because it is a good vacation destination. Bala, the town, is located at the southwest shores of the lake and Gravenhurst is Southeast corner. The vegetation that covers the shoreline is mostly trees and some ferns. The fauna in the lake consists of many cold water fish species such as the lake trout, brook trout, loon, small mouth bass, many other kinds of trout, northern pike, small mouth bass and many other fish. =Threats=

Lake Muskoka is threatened by some common threats like most lakes. These threats are motor boats, septic tanks, docks, boat waves, beaches and clearing the shoreline. Motor boats leak oil which in the water reduces the oxygen level and it affects the health of the lakes organisms. The septic tanks can leak and increase the nitrogen content in the water which harms the biodiversity. When docks are built it disturbs the fish breeding area and the aquatic plants. Boat waves disturb the nesting sites of some animals and they also disturb the plants. When beaches are made or the shoreline is cleared for a reason this removes the fish's shade and cover it also destroys the habitat for some animals. All of these threats affect the biodiversity of the lake.

A bigger threat that is really affecting Lake Muskoka is phosphorus. Phosphorus is a chemical that has high reactivity and causes an algae bloom. It is found in soaps, cleaners, fertilizers and sewage. Storm water and erosion may also bring it to the lake. When there is too much phosphorus in the water it speeds up eutrophication and lowers the oxygen level in the water which can cause a severe reduction in fish and other animal populations. If nothing is done the excess nutrient in the water might allow an invasive species to come in the water and compete with the other inhabitants.

Eutrophication is another problem that is really affecting Lake Muskoka. Eutrophication occurs when a lot of excess nutrients are put into an ecosystem. Many human activities are the causes of these excess nutrients being put into ecosystems. Some of these activities are runoff from farming, pollution from septic tanks and many other activities. Phosphorus is a main cause of eutrophication in most lakes. Luckily, some policies are being made to have a better control over Eutrophication.

=Ways to stop and prevent threats=

To prevent some of the common and basic threats many things can be done. If people replace their old septic tanks with newer versions, and then replace those when they start to go bad the leaks can be prevented. We observe the lake and build the docks in better places where the fish wont be affected as much. Since, not much can be done about boat waves we can at least use boats that wont leak oil and try to not use them as much. Also, before clearing part of a shoreline on a lake you should have to consult an expert, and have him examine the area to make sure it won't affect the lake ecosystem a lot.

To prevent phosphorus people could try and buy cleaners, soaps and fertilizers that don't contain it or a law could be made that doesn't allow the use of phosphorus in cleaning ingredients. To prevent the erosion people should not clear much of the shoreline, but if they do clear some they should consult somebody to make sure the part they cleared isn't going to affect the environment greatly. Some farmers are now using the minimum amount of fertilizer on their crops to prevent the amount of runoff. Since they don't use as much fertilizer they are loosing less money while the environment remains cleaner.

Since eutrophication is a main threat many things are being done to prevent it. Many clean up measures are being taken to get rid of the phosphorus and other nutrients which can cause it. Most of these measures have been successful, but some have not. In Finland, during the 1970s they started targeting polluted lakes and rivers to get rid of the runoff which brings the nutrients into the water. Most targeted points were successfully cleaned but some did not show a decrease in runoff. In some places, many laws have been placed on the treatment of sewage. These laws led to a great reduction of nutrients in many ecosystems. The public must be aware for us to prevent and stop these threats. Policies don't have any effects if the public doesn't know about them and what they can do to contribute. If we want to prevent pollution and other threats in places cooperation is also very important. Since many of these threats affect more than one place we can work together with the other people being affected and fix these problems.

=Conclusion=

I learned a lot during this assignment about the threats affecting lake ecosystems and what we can do to stop it. I hope it also made you aware about the threats that ecosystems are faced with and what we can do to stop them. Lake Muskoka is very important to some people and it is a big part of the lives of many animals. Lakes are very important because they give us a lot of the water we drink so it is vital that we preserve this great ecosystem. If we preserve ecosystems like Lake Muskoka future generation can enjoy it and many animals will still have a home and will not become endangered or threaten.

=Sources= [] [] [] [] [] http://en.wikipedia.org/wiki/Lake_Muskoka