ecosystems
DESCRIPTION
TRANSCRIPT
-AQUATIC ECOSYSTEMS-TERRESTRIAL ECOSYSTEMS-MIXED ECOSYSTEMS
THERE ARE 3 TYPES OF ECOSYSTEMS:
AQUATIC ECOSYSTEMIt´s any water-based environment in which plants and animals interact with the chemical and physical features of the environment.
Aquatic ecosystems are generally divided into two types:
* Freshwater ecosystem * Marine ecosystem
They cover over 70 percent of the earth's surface. Oceans, estuaries and coral reefs are the various kinds of marine ecosystems.
Oceans are large salt-water bodies connected across the earth. The ocean floor is made up of shelves, plains and mountain ranges. There are currents moving water between different oceans. Waves and tides are also ocean movements.
The place where fresh and salt-water meet
are called estuaries. This is a unique place where two habitats come together.
Coral are polyps that live together in big groups, fixed to rocks. As they grow they generate a kind of skeleton common to the whole colony. These skeletons grow very bib and are called coral reef. However they grow very slowly over time. In fact, an inch of coral reef takes nearly 100 years to grow! These places are a true paradise but they are also very fragile.
They cover less than 1 percent of the earth and are subdivided into streams, rivers, ponds and lakes.
Lakes are large bodies of freshwater surrounded by land, while ponds are smaller bodies of water surrounded by land.
Rivers and streams are moving bodies of fresh water which usually originate in mountains and come from melting ice or ground water and eventually terminate in oceans.
TERRESTRIAL ECOSYSTEMTerrestrial ecosystems are land-based ecosystems.They range from the coldest places on earth to the hottest deserts found around the equator. Each ecosystem is inhabited by species of plants and animals that have evolved to thrive in them.
Terrestrial ecosystems are generally divided into 4 types:
• Forest: - Coniferous forest - Deciduous forest - Rainforest/Jungle
• Tundra
• Desert
• Grassland/Savannah
Trees are the most important living things in a Forest. Trees provide food and shelter for many animals.
Coniferous forest: the one that has trees that reproduce by dropping cones. They are adapted to the cold weather.
Deciduous forest: They do not bear cones, they contain seeds. They lose their leaves ones a year when the weather turns cold. The weather tends to be moderate.
Rainforests: They are filled with millions of plants and animals. They are located near the equator with lots of rain. This is known as the jungle.
Grasslands are big open spaces. Tall grass is the most characteristic feature, there are not many bushes. Trees are found only by rivers and streams. The grassland seems like an endless ocean of grass. Large animals, such as zebras, gazelles or antelopes, graze here:
that is, they eat the grass. It´s also known as Savannah.
Deserts are known to be hot, dry biomes. But there are also "cold" deserts. In these deserts the nights are very cold, especially in the winter. As there is little rainfall, few types of plants exist. Many of the animals live underground for much of the day. They adapt to the heat by hiding under rocks when the sun is out.
How cold is cold? The Tundra ecosystem is at the top of the world -- around the North Pole! Tundra is a place too cold for many animals or plants to survive. Often the land is covered with snow most of the year, with much of the ground frozen. The summer season is very short and many animals hibernate to survive the cold winter.
MIXED ECOSYSTEMThey combine both terrestrial and aquatic ecosystems. They can be:
Wetland: Seasonal wetlands are flooded in the winter and begin to dry out in the summer. The moisture content of these biomes changes seasonally. Rains arrive in the winter and begin to fill the area with water. With the arrival of water, insects, reptiles, birds, and small mammals populate the wetlands. As spring arrives, the plants in the wetlands begin to grow and bloom, providing an additional food sources for the residents. As summer approaches, seasonal wetlands begin to dry out. The green colors of spring turn to tan and the populations change as some small animals move deeper into the muddy soils.
Coastline: The coast is where the land meets the sea. Coastal life must be adapted to environmental factors that grade from one extreme to another, especially from wet to dry; wave action; and particle sizes of bottom materials. Because these zones are close to land, there are certain related plants and animals that have adapted to these conditions. This zone is also one of the most important for humans.