CHAPTER 12
12.1
FRESHWATER ENVIRONMENTS

Freshwater environments can have up to deep oceans with oceans that move quite fast and then some that have really soft, wet grounds. Many animals don't change their habitat of water. Many animals have to live in freshwater and saltwater in order to survive. For example, salmon(fish) swim in an open ocean area, they then come back to the freshwater to lay their eggs. There are many plants and animals living in the ocean. In order for them to grow and have different types of creatures in the ocean, it depends on how far down into the water the light of the Sun reaches, how healthy the water is, how fast the water is moving and what is the oxygen level. Stickleback fish can stay in many types of water and they will still survive.

LIFE IN LAKES AND PONDS

Many creatures that live in a lake or a pond live at the edge of the water, close to the land. The reason for that is because the water near the shores is shallow and there is a lot of healthy food there for them to eat and survive. In the center of the lakes or ponds live very tiny organisms called plankton. There are two types of plankton: Phytoplankton and Zooplankton. Phytoplankton are plants that produce healthy food by going through the process called photosynthesis. Zooplankton are very small animals which eat other planktons as their food. These planktons are first on the food chain because they produce food for the other living things. Many amphibians that live in ponds or lakes are frogs, salamanders and large fish which live in the deep ends. Mammals and birds have their own homes built too on the shorelines near the lakes and ponds. Two examples in British Columbia are beavers and muskrats. Lakes and ponds are very important to the environment because they make the run-off flow to the oceans and rivers. Freshwater environments provide a home for plants and animals and root cleaning the water by their process.

LIFE IN WETLANDS

There is at least one quarter of wetlands in British Columbia. Wetlands are places where creatures breed, 90 percent of wetlands are destroyed because of construction. Wetlands help in the world in a lot of ways. They help get rid of pollution in the water by vegetation, they keep the floods from happening on the Earth and a lot of fish of British Columbia lay their eggs on wetlands. Many animals make their home as the wetlands. Thick vegetation makes shorelines get rid of erosion and the endangered species life cycles are the wetlands.

LIFE IN RIVERS AND STREAMS

It depends on which creatures live in the rivers because of these two things: how fast the water moves and how much turbidity is in the water. Weeds, mosses and alge are all different types of plants which live in rivers. Insects live on and in the rivers and they lay their eggs along the riverbed. At the bottom of the streams, you can find snails and worms. Trout, pike and catfish are all different types of fish which eat tiny organisms.

LIFE IN ESTUARIES

An estuary is when a river and an ocean meet forming saltwater to mix with freshwater. Clean water which comes from the land slowly mixes from rivers and the oceans into estuaries, which means this is a very good place for animals and plants to live because of the mixture of water. Then the nutrients get transported by the wind, tides and currents through the environment. There are about 3 percent of estuaries that are on the coastline of places and 80 percent that are actually controlled by living animals.

12.2
SALTWATER ENVIRONMENTS


There are two types of ocean water: the pelagic zone and the benthic zone. The pelagic zone is separated further into more subzones: the sunlight zone, the twilight zone and the midnight zone. The benthic zone is divided into two more sub zones: the abyssal zone and the hadal zone. The pelagic zone is the upper layer of the ocean. The sunlight zone is the top of the saltwater ocean which has photosynthesis in the plants. The twilight zone is the part of the ocean which can't make plants grow because there is very little sunlight reaching to that zone. The midnight zone is where there is no sunlight reaching there at all because it is the very bottom of the ocean. The benthic zone is the bottom layers of the ocean. The abyss zone is the part of the ocean which always is very cold and has a lot of water pressure forming. The hadal zone is only found in deep cracks of the Earth's rock. The pelagic zone is more involving the life of the oceans because there is more food and sunlight is those areas. Almost 90 percent of living things live in the upper area of the ocean. In the lower area of the ocean there is hardly any sunlight so the plants don't grow which means that there aren't much living creatures living there. Almost 10 percent of living creatures live in the lower area of the ocean. In order for them to find food in the darkness, they use bioluminescence. Bioluminescence is a special reaction that lights up their bodies in order for them to see.

SALTWATER LIFE FORMS

Shallow water which is most likely close to the equator are homes of living creatures like fish and plants. Larger fishes like the tuna and halibut live in much colder parts of the oceans. Sea sponges, tube worms and sea cucumbers live on the ocean floor eating plankton( small plants) and dead creatures. Sea urchins, crabs, sea stars, mussels and clams eat the organisms which are bacteria and diatoms.