Marine Food Web

Marine Food Web

Friday, May 21, 2010

Endangered Animals in the Ocean Biome

A baby hawskbill turtle.
A humpback whale meandering aimlessly in the water.

A tiger-tailed seahorse searches for food at the depths of the ocean.

Saturday, May 15, 2010

Carbon Source, Carbon Sinks, Release Agents

A carbon sink is anything that removes the carbon from the air. For example, some plants in the ocean uses photosynthesis to take in the carbon. The plants then give out oxygen for fishes to breathe. Also, the phytoplankton in the ocean also takes in the carbon. Some carbon sinks on the land include long -lived trees, limestone, and shells. You can think of carbon sinks as incinerators. The carbon sinks take out the carbon, and the carbon disappears.

A carbon source is anything that gives out carbon. For example, burning fossil fuels is a carbon source. The burning releases carbon, which joins with oxygen to become CO2. The oxygen we breathe has two molecules, representing the two in CO2. Carbon is C, and there is only one molecule of carbon in each piece. Carbon sources can vary from a train running on coal to people breathing and sticking their tongue out. Just as how a mother gives milk to her baby, the carbon source gives out carbon.

A release agent is anything that releases out carbon. Unlike carbon sources, release agents are natural. For example, a volcano has to blow off its top sometime. Volcanic activity could release carbon into the air as a billowing ash cloud. Maybe, a thunderstorm may occur and lightning may strike. Some trees could get on fire. Burning of trees releases carbon as well. But this cause is natural. Some of other examples of release agents include peace signs and people jumping rope.

Food Web Vs. Food Chain

Before learning about the food chain, you need to understand what the difference is between a food chain and a food web. A food chain consists of six items: the energy source, the producer, the primary consumer, the secondary consumer, the scavenger, and the decomposer. Each of these items play a role in the food chain and are needed for the balance of life. Even though helpless animals may be sacrificed, everything plays its role in the food chain. A food web consists of many interlocked food chains in an area called a biome. A biome is an area of the world that has different characteristics such as temperature, humidity, and rainfall from other biomes. A food web has only one energy source, but many producers, consumers, scavengers, and decomposers are involved.

Energy Source

The energy source (the sun in this case) is vital for the food chain to start. The sun gives energy for the producers to make their own food. Because of this, the food chain is able to flow along smoothly and undisturbed. However, if the sun is taken out of the food chain, the consumers would become carnivores, feasting upon each other because producers are taken out of the food chain. Also, scavengers wouldn't have anything to eat, and the decomposers wouldn't have anything to decompose too. Soon the decomposers and the scavengers would become extinct.


A producer is an organism that produces its own food from the sun. For example, in an ocean biome, a type of producer is kelp. This plant makes its own food from the energy of the sun. Kelp makes chlorophyll, a pigment that makes this plant green. As you can see in the picture over here, the kelp forest is all green from chlorophyll. Through a process called photosynthesis, kelp takes energy from the sun and CO2. Using those items, kelp makes glucose, a type of sugar which it feeds on. Plankton is also a producer. Plankton also takes energy from the sun and converts it into its own food. To sum it up, seaweed is also a producer in the ocean biome. A primary consumer is an animal that eats a producer. Producers are important to the food chain. If there were no producers, all consumers would become carnivores, or meat-eating animals. When all the consumers eat meat, they would have to reproduce fast enough in order for the food chain to stay in place. Scavengers would have to work more, and decomposers would have to decompose the dead animals, making them into rich soil. But what is the use of good, rich soil without any producers to take in the rich nutrients and humus?

Primary Consumer

In one of the examples before, we had kelp as a producer. The kelp is eaten by fish such as the halfmoon fish, a fish called the opalaye, and clown fish. Therefore, the opaleye fish, the halfmoon fish, and the clown fish are all primary consumers. Plankton is eaten by whales, which filter the plankton by its teeth. Whales are then a primary consumer. Seaweed is also eaten by crabs, making them a primary consumer. IF primary consumers were taken out of the food chain, the food chain would not be able to manage along. Instead of energy source<-- producer<-- primary consumer<-- secondary consumer<-- scavenger<-- and decomposer, the food chain would become energy source<-- producer<-- secondary consumer<-- scavenger<-- and decomposer. With this layout of the food chain, four main problems would happen. First, the secondary consumers' food would disappear. The secondary consumer would have to eat its own kind to survive, so the secondary consumer has to reproduce more often in order to keep it in balance. Even though reproducing faster could be a solution, most secondary consumers today don't reproduce fast enough. One other problem is that all the producers alive would suck up the rich nutrients and humus from the soil. Later on, there would be no nutrients in the soil, because the decomposer has fewer carcasses to decompose. Then the producers would die out. The next problem is that there wouldn’t be enough carcasses for the scavenger to feast on. Once all the consumers die out, the scavenger wouldn’t have any food and would soon decline in number. Finally, the decomposer would decompose the dead scavengers. The decomposer wouldn't have anything to eat, and would soon become extinct.

Secondary Consumer

A secondary consumer is a consumer that eats a primary consumer. Even though a secondary consumer eats a primary one, a secondary consumer is usually an omnivore. An omnivore is an animal that eats both plants and animals. Other bigger fish would probably eat the clown, halfmoon, and the opaleye fish. Thus, these predators are secondary consumers. Whales could be eaten by killer whales, so killer whales are a secondary consumer. Since sea gulls eat crabs, you can probably guess what sea gulls are: secondary consumers. If there aren't any secondary consumers in the food chain, many problems would happen. First of all, the amount of primary consumers would increase, and would be unregulated. Because of this, overgrazing would occur to the producers. Overgrazing is when producers are eaten to an extent that the producer would not be able to grow again. Once overgrazing happens, the primary consumers would slowly decline and would be feasted upon by the scavengers. The scavengers then would start to diminish in number, and would become extinct. The carcasses are then decomposed by the decomposer. Soon enough, the carcasses to be decomposed would run out, and the decomposers would soon die and become extinct.