59 L6-Wonderful Ecosystems

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Oxford Read and Discover level 6 Wonderful Ecosystems by Louise & Richard Spilsbury

Introduction There are millions of living things on Earth, from the smallest plants to enormous whales. These plants and animals live in different places, like oceans, rainforests, and deserts. These different places and all the things that live in them are called ecosystems. What ecosystems are there where you live? What ecosystems do you know? What lives in these ecosystems? Discover! Now read and discover more about wonderful ecosystems on Earth!

Chapter 1 What Are Ecosystems? In an ecosystem there are living things, like plants and animals, and things that are not living, like rocks, water, and air. Together, these things make an ecosystem. Living Together The different parts of an ecosystem work together and use each other. For example, in a garden ecosystem, plants use the land, water, light, and air to live. Bees visit plants to drink nectar from their flowers. When bees do this, they also take pollen from one plant to another. Pollen helps flowers to make seeds that can become new plants. Discover! A bee can visit 100 flowers in just a few hours! Food Chains All living things need food. In most ecosystems, plants use sunlight to make their food from carbon dioxide in the air and water. Animals eat plants or other animals that eat plants. Decomposers are living things that feed on things like dead leaves or dead animals. Food chains show us how plants and animals in an ecosystem work together. They show us what eats what in an ecosystem. In the food chain above, a grasshopper eats grass, a snake eats the grasshopper, and a buzzard eats the snake. When the buzzard dies, its body falls onto the land. There, decomposers, like bacteria and fungi, feed on the buzzard. When they do this, some of the nutrients from the buzzard's body go into the land. Plants, like grass, then use these nutrients to help them to grow.

Different Ecosystems Different ecosystems are different sizes. Some ecosystems are big, like an ocean or a forest. Others are small, like a pond or a tree. There are thousands of plants and animals in a forest, but a dead tree can be a busy ecosystem, too! Fungi and other plants grow on it and many small animals live in it and feed on it. There are lots of different ecosystems because of the weather and the type of land in them. For example, few plants grow in deserts because it doesn't rain there often and so it's too dry for most plants. Many trees grow in rainforests because the weather there is rainy and warm. Living in Ecosystems Some animals live in only one ecosystem. Pandas live only in bamboo forests because bamboo is the only food that they eat. Other animals can live in different types of ecosystem, like bees that can live in forests, gardens, and other places. Many animals are adapted to their ecosystem. For example, monkeys have long arms and legs for climbing trees in a forest, and polar bears have thick fur to keep them warm in frozen ecosystems. Discover! Some living things share the same food in an ecosystem by feeding at different times. For example, owls hunt for rabbits at night, and hawks hunt for rabbits in the day.

Chapter 2 Hot Deserts When we think of deserts, we imagine rocks and sand and a place that's very hot and dry. It's difficult to live in a hot desert, but some plants and animals are adapted to this ecosystem. Desert Plants Deserts are dry because it almost never rains. Desert plants collect the rain and store it so that they can live during the dry season. Cactus plants have stems that become fat when they are full of water. They also have sharp spikes to stop thirsty animals breaking the stems to drink the water inside. The spikes don't stop birds making nests on the cactus plants! Desert Food Chains Like other food chains, desert food chains start with plants. Desert bats drink nectar from cactus flowers, and insects and other small animals eat leaves or seeds from desert plants. Scorpions and lizards eat insects, like crickets, and other small animals. Animals that hunt and eat other animals are called predators. Some big predators in the desert are hawks, snakes, and foxes. Meerkats are desert animals that eat plants and insects, but they also eat scorpions. In their tail, scorpions have venom— a juice that can kill other animals. So how do meerkats eat scorpions and live? They quickly break off the tail and throw it away. Then it's safe for the meerkat to eat the scorpion!