Ecosystems PDF

## More about ecosystems The ecosystem in the Arizona Sonoran Desert is just one of many different ecosystems on Earth. Here are some more examples of ecosystems: mangrove forests, sea ice in the Arctic Ocean, and a rice paddy. ### Mangrove forest * Mangroves are trees that can grow with their ro...

## More about ecosystems The ecosystem in the Arizona Sonoran Desert is just one of many different ecosystems on Earth. Here are some more examples of ecosystems: mangrove forests, sea ice in the Arctic Ocean, and a rice paddy. ### Mangrove forest * Mangroves are trees that can grow with their roots in sea water. They form forests along the coasts of many tropical countries. * Young fish live among the mangrove roots, safe from larger fish that might eat them. Mud skippers climb out onto the mud when the tide is out, feeding on whatever they can find. * As the mangrove leaves fall onto the mud, they are decomposed by bacteria. Prawns and crabs eat the partly decomposed leaves. * Crab-eating macaques, a type of monkey, climb through the trees and catch crabs on the tree roots and mud. ### Sea ice in the Arctic Ocean * During the winter in the Arctic Ocean, it is so cold that some of the sea water freezes. * Seals hunt for fish in the water, but have to come to the surface to breathe air. * Polar bears patrol the ice, looking for seals to kill and eat. Polar bears are good swimmers, and can move from one ice floe to another. * Arctic foxes also look for food on the ice. * Enough light passes through the ice to allow tiny algae (single-celled plants) to grow on the underside of the ice floes. * Tiny shrimp-like organisms eat the algae. * Fish eat the shrimp-like organisms. ### Rice paddy * Not all ecosystems are natural. This area of rice paddies in Malaysia is farmed by people. * At some times of year, the paddy fields are flooded with water. Algae grow in this shallow water, and on the mud at the sides of the flooded areas. * Fish swim into the flooded paddies from the irrigation canals. Frogs and dragonflies breed in the water. * Because the water is shallow, it heats up quickly during the day, and cools down quickly at night. * Farmers often add fertiliser to the paddy fields, making not only the rice but also the algae grow faster, providing more food for the animals. * Many birds feed in and around the paddy fields. ## Activity 4.2.1 ### Habitats in an ecosystem