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The Ocean Coastal Zone Essay Research Paper

INTRODUCTION

Ecology is the study of living things interacting with its environment, other species,

and its own kind. It?s a study of all external condition and factors, both biotic ( living ) and

a-biotic ( nonliving ), that affect an organism. To carry out this study, scientists observe

different ecosystems: forests, deserts, grasslands, oceans, or any kind of interaction

between organisms and their surroundings, or with each other, which are called ecosystem

effects.

There are four components within an ecosystem. The a-biotic component, which

determines the types of organisms found there, the producers, the consumers, and the

decomposers. These components cause continual change within the system; the exchange

of materials between the living and nonliving. All organisms living within an ecosystem are

dependent on other living and nonliving organisms for survival and continued growth.

Two basic kinds of processes must occur in an ecosystem: a cycling of chemical

elements and a flow of energy. The flow of energy is from the external environment

through a series of organisms and back to the external environment. To preserve the

system, we must try to conserve the specie or manage the natural resources so that they

are sustainable.

THE OCEAN

The ocean is the great body of water that surrounds each continent. Covering more

than 70 percent of the earth?s surface, it contains 97 percent of all the water on the earth

and is recognized as the earth?s greatest single unifying system.

Studies say that the sea was formed due in part of the continental drift. This theory

states that the continents were once a single great mass of land surrounded with one body

of ocean. The mass broke off into separate continents, slowly drifting apart. That explains

why these continents can perfectly fit together like a jigsaw puzzle. The continental drift

theory was questioned, and later scientist formed a new theory called sea-floor spreading,

which explained the forces that caused the continents to move. And even later, another

theory was formed, called plate tectonics, which combined the two theories together.

The coast is the edge of the land, the beginning of the sea, the brink of the beach, the

rim of the ocean. It?s the conflict between human activities and natural forces that is

widespread along the open shoreline. Humans have begun to inhabit the coastline area.

They find the ocean breeze to be so overwhelming that now, many live in houses along the

coast. It disrupts a delicately balanced environment and imperils the lives and property of

coastal dwellers.

The continental shelf belongs to the land and to the sea. It is the submerged land at

the edge of the continents; the thin strip at the edge of land and the surface of the sea. The

shelf begins at the shoreline and gently slopes underwater to an average depth of 430 feet,

having a width averaging 47 miles. In the Arctic region it extends 750 miles, while in the

Pacific region it measures only 1 mile. It encounters the land, air, bright sunlight, grasses

and trees, rain and snow, rivers and glaciers. The shelf supports every class of creature

from bacteria to mammals, both inland and in the sea.

The sea absorbs all changes and the sea creatures would always find regions of

stability and abundance. It experiences only light, sudden extinction and replacements. The

ocean has gradually accepted new types of life, but also maintained many of the old ones.

All over the world sea levels rise and fall, causing disruptive changes that greatly effects its

surroundings. Nothing can really be done to stop these changes, for its all part of nature.

CLIMATE

The surface temperature of the sea varies depending on where it is located. It?s

about 28 degrees Fahrenheit near the North and 86 degrees near the equator. In the polar

regions the surface seawater freezes and the water in the western tropical pacific is the

warmest of them all. As the currents move in the ocean, they carry warm tropical water

toward the poles. Other ocean movements bring colder, deeper water up to the surface,

which lowers the surface water temperature. The water temperature also varies with

depth. The temperature falls as the depth increases.

Oceans also affect the global cycling of chemical elements. They are a major

storehouse of carbon. It exchanges carbon dioxide with the atmosphere, therefore, playing

a major role in the rate of global warming.

LIFE IN THE SEA

There is an incredible variety of living things living in the ocean. Life in the oceans is

so diverse and abundant that you could find anything from a one-celled organism to the

largest animal that has ever lived – the blue whale. All ocean life can be divided into

groups.

THE PLANKTON

The plankton consists of plantlike organisms and animals that drift with the ocean

currents. They are formed into two groups: the phytoplankton, and the zooplankton. The

phytoplankton consists of several kinds of plantlike organisms. Algae are found mostly

anywhere in the ocean. Certain types have the ability to make their own food by

photosynthesis, and others absorb nutrients from their surroundings. Algae may

reproduce in more than one way. Some split into two or more parts, each part becoming a

new, separate plant. Others produce spores and some reproduce sexually -cells from two

different plants unite to create a new plant. Green plants are mostly found in protected

areas of the continental shelf where their roots can find soil and nutrients. Diatoms and

dinofllagellates are also numerous members. Both are one-celled but the diatom lives in

the colder regions while the dinoflagellate lives in the tropical regions.

The zooplankton consists of many kinds of animal, ranging from one-celled

organisms to jellyfish up to 6 feet wide. These animals live in surface and deep waters of

the sea and must maintain a balance in body fluids and salt levels in their blood. Majority

of zooplanktons are larva?s, copepods and hydromedusa?s. They depend primarily on the

food supply, so the lack of sudden temperature changes in the water does not effect them

greatly. In fact they find the change in their environment rather comfortable.

MARINE ANIMALS

Marine animals are classified as microorganisms, vertebrates, and invertebrates.

Bacteria, a form of microorganism is found throughout the ocean and make up much of

the dissolved matter in the waters. They also help decompose the dead bodies of larger

organisms. It obtains food and oxygen by means of chemosynthesis; a process in which the

organism creates food using chemical nutrients as the energy source instead of sunlight.

The bacteria live in cooperation with animals unique to this region, providing them with

important nutrients.

Animals without backbones are called invertebrates. Lobsters and clams are probably

the most numerous and diverse group. Invertebrates in the ocean range from jellyfish to

worms and crabs.

Vertebrates are animals with backbones. Reptiles, fish, dolphins, whales, shark, and

seabirds can all be found in the sea. The body temperature of reptiles changes with the

temperature of their surroundings. Two kinds found in the ocean are the sea turtle, and the

sea snake. At least 15 species of snakes are found in the tropic. There are more than 350

species of shark found in the sea. Most of these live in coastal waters and only six species

favor the mid-ocean. They are most abundant in tropical and subtropical waters. But still

the three most important mammals that are truly marine are whales, porpoises, and sea

cows because they must remain in the water at all times.

BIOLOGICAL DIVERSITY

Biological diversity can be understood as the variety of life on the Earth, but it

consists of three components. The first component is genetic diversity, the total number of

genetic characteristics. The last two are species diversity and habitat or ecosystem

diversity. The most familiar level of biological diversity is species diversity, or the number

of species living in a particular habitat. It includes three concepts: species richness,

evenness, and dominance. The most species-diverse marine habitats occur in the tropical

waters, and among the tropical areas. We don?t know how many marine species are

around exactly, but we do know that there are far more species on land than in the seas.

THE IMPORTANCE OF THE OCEAN

The ocean is far more useful than just a place for swimming, boating, surfing, and

other fun activities. It serves as a source of food, energy, and minerals, and also as the

transportation route of shipping cargo. Not just that, but it also helps keep the earth?s

climate healthful by regulating the air temperature and by supplying the moisture for

rainfall. If there was no ocean, life would not even exist on our planet.

RESOURCES

Humans have depended on the oceans for food, primarily fish. Humans eat about 60

percent of the fish and the rest is used for livestock feed, and processed into pet food.

Seaweed is eaten because it is high in vitamins and minerals. Algae is used to thicken ice

creams and puddings. Sea salt is another food item taken from the ocean. The crystals are

collected, processed, and packaged. Sea water is also desalted and used by some desert

countries for drinking and irrigation.

The most valuable energy resources from the ocean are petroleum and natural gas, in

which 25 percent of the world?s oil and gas are deposited beneath the sea. Ocean tides

also provide energy. Tidal power facilities use the energy in the rise and fall of the tides to

produce electricity.

Minerals recovered in the ocean include sand, bromide, manganese, and salt.

Copper, iron and zinc can be found deeper in the sea. These minerals are used in creating

medicines and are used in vitamin pills.

POLLUTION

The ocean plays an important role in our global environment. Although we do not

live in the ocean environment, we are the ones who cause the pollution in the waters. And

if pollution constantly occurs, what would become of these great masses of water?

Because of it?s great size and natural chemical processes, the ocean can absorb some

pollutants, but it will not absorb it all. Each type of marine waste- synthetic chemicals, oil,

marine debris, exotic species, sewage- behaves in different ways and present different

threats to ocean resources. Little is known about what happens to these chemicals when

they enter the water stream. But we do know that some accumulate into the tissues and

organs of aquatic animals, others may be excreted. Oil spills are major factors of water

pollution. These spills seriously disrupt marine ecosystems, and the effect of these

disruptions can be long-lasting. These spills are disastrous towards the water and

coastlines; killing both sea and land organisms. The deliberate dumping of waste products

also play a major role. It consists of everything from left over food to chemicals. Plastics

dumped into the sea don?t easily break down. Organisms in the sea either eat the plastic,

which blocks their digestive system, and causes starvation. They can also become

entangled with them, causing them to drown. With all these problems, how do we keep

the marine animals and plants from becoming extinct? What kind of future will the seas

have?

THE FUTURE OF OUR SEAS

The ocean has a huge impact in our lives, and it should continue being that way. But

we do need to make some changes in protecting and keeping the ocean clean. In the past

some marine animals have been thought as pests so they were eliminated. It is also human

use of the coastal zone that is the most serious threat to these animals. Our coasts and

nearshore islands play a vital role in their lives, and new strategies are being processed in

protecting the endangered species.

Steps have been taken in preserving the coastal zones, but we will have to make

difficult choices. Should public access to some beaches be restricted to allow seals and sea

lions an area for hauling out water and breeding? Should fishermen be required to provide

protection for dolphins caught in nets? These are just a few questions that involve hard

decision making. Effects of pollution on these endangered species are also taken into

consideration. New laws came up with the Endangered Species Act, and the Coastal Zone

Management Act. But the problem is that little is done to follow through with them. I feel

that the dumping of anything, either harmless or harmful, into the sea should be forbidden.

This way the ocean has a better chance of staying clean.




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