9781422284926

environmental Science

SCIENCE 24/7

A nimal S cience C ar S cience C omputer S cience E nvironmental S cience F ashion S cience F ood S cience H ealth S cience

M usic S cience P hoto S cience S ports S cience T ravel S cience

SCIENCE 24/7

environmentAL Science

Jane P. Gardner

Science Consultant: Russ Lewin science and Math educator

Mason Crest

Mason Crest 450 Parkway Drive, Suite D Broomall, PA 19008 www.masoncrest.com

© 2016 by Mason Crest, an imprint of National Highlights, Inc.

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, taping, or any information storage and retrieval system, without per- mission from the publisher.

Printed and bound in the United States of America.

Series ISBN: 978-1-4222-3404-4 Hardback ISBN: 978-1-4222-3408-2 EBook ISBN: 978-1-4222-8492-6

First printing 1 3 5 7 9 8 6 4 2

Produced by Shoreline Publishing Group LLC Santa Barbara, California Editorial Director: James Buckley Jr. Designer: Patty Kelley www.shorelinepublishing.com Cover Image from Dollar Photo Club.

Library of Congress Cataloging-in-Publication Data on file with the Publisher.

IMPORTANT NOTICE The science experiments, activities, and information described in this publication are for educational use only. The publisher is not responsible for any direct, indirect, incidental or consequential damages as a result of the uses or misuses of the techniques and information within.

Contents Chapter 1: Rising Temperatures Chapter 2: The Power of Recycling

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12 16 20 24 28 32

Chapter 3: Clean Water Chapter 4: Coral Reefs Chapter 5: Deforestation

Chapter 6: The Impact of Mining Chapter 7: Invasive Species Chapter 8: Endangered Species 36 Chapter 9: Conclusion: Concept Review 40 Find Out More 44 Series Glossary of Key Terms 45 Photo Credits 46 About the Author 47 About the Consultant 47 Index 48

Key Icons to Look For

Words to Understand: These words with their easy-to-understand definitions will increase the reader’s understanding of the text, while building vocabulary skills.

Sidebars: This boxed material within the main text allows readers to build knowledge, gain in- sights, explore possibilities, and broaden their perspectives by weaving together additional in- formation to provide realistic and holistic perspectives. Series Glossary of Key Terms: This back-of-the-book glossary contains terminology used through- out this series. Words found here increase the reader’s ability to read and comprehend higher- level books and articles in this field.

Introduction S cience. Ugh! Is this the class you have to sit through in order to get to the cafeteria for lunch? Or, yeah! This is my favorite class! Whether you look forward to science or dread it, you can’t escape it. Science is all around us all the time. What do you think of when you think about science? People in lab coats peering anxiously through microscopes while scribbling notes? Giant telescopes scanning the universe for signs of life? Submersibles trolling the dark, cold, and lonely world of the deepest ocean? Yes, these are all science and things that scientists do to learn more about our planet, outer space, and the human body. But we are all scientists. Even you. Science is about asking questions. Why do I have to eat my vegetables? Why does the sun set in the west? Why do cats purr and dogs bark? Why am I warmer when I wear a black jacket than when I wear a white one? These are all great questions. And these questions can be the start of something big . . . the start of scientific discovery. 1. Observe: Ask questions. What do you see in the world around you that you don’t un- derstand? What do you wish you knew more about? Remember, there is always more than one solution to a problem. This is the starting point for scientists—and it can be the starting point for you, too! Enrique took a slice of bread out of the package and discovered there was mold on it. “Again?” he complained. “This is the second time this all-natural bread I bought turned moldy before I could finish it. I wonder why.” 2. Research: Find out what you can about the observation you have made. The more in- formation you learn about your observation, the better you will understand which ques- tions really need to be answered. Enrique researched the term “all-natural” as it applied to his bread. He discovered that it meant that no preservatives were used. Some breads contain preservatives, which are used to “maintain fresh- ness.” Enrique wondered if it was the lack of preservatives that was allowing his bread to grow mold. 3. Predict: Consider what might happen if you were to design an experiment based on your research. What do you think you would find? Enrique thought that maybe it was the lack of preservatives in his bread that was causing the mold. He predicted that bread containing preservatives would last longer than “all-natural” breads.

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4. Develop aHypothesis: A hypothesis is a possible answer or solution to a scientific prob- lem. Sometimes, they are written as an “if-then” statement. For example, “If I get a good night’s sleep, then I will do well on the test tomorrow.” This is not a fact; there is no guarantee that the hypothesis is correct. But it is a statement that can be tested with an experiment. And then, if necessary, revised once the experiment has been done. Enrique thinks that he knows what is going on. He figures that the preservatives in the bread are what keeps it from getting moldy. His working hypothesis is, “If bread contains preservatives, it will not grow mold.” He is now ready to test his hypothesis. 5. Design an Experiment: An experiment is designed to test a hypothesis. It is important when designing an experiment to look at all the variables. Variables are the factors that will change in the experiment. Some variables will be independent—these won’t change. Others are dependent and will change as the experiment progresses. A control is nec- essary, too. This is a constant throughout the experiment against which results can be compared. Enrique plans his experiment. He chooses two slices of his bread, and two slices of the bread with preservatives. He uses a small kitchen scale to ensure that the slices are approximately the same weight. He places a slice of each on the windowsill where they will receive the same amount of sunlight. He places the other two slices in a dark cupboard. He checks on his bread every day for a week. He finds that his bread gets mold in both places while the bread with preservatives starts to grow a little mold in the sunshine but none in the cupboard. 6. Revise the hypothesis: Sometimes the result of your experiment will show that the original hypothesis is incorrect. That is okay! Science is all about taking risks, making mistakes, and learning from them. Rewriting a hypothesis after examining the data is what this is all about. Enrique realized it may be more than the preservatives that prevents mold. Keeping the bread out of the sunlight and in a dark place will help preserve it, even without preservatives. He has decided to buy smaller quantities of bread now, and keep it in the cupboard. This book has activities for you to try at the end of each chapter. They are meant to be fun, and teach you a little bit at the same time. Sometimes, you’ll be asked to design your own ex- periment. Think back to Enrique’s experience when you start designing your own. And remem- ber—science is about being curious, being patient, and not being afraid of saying you made a mistake. There are always other experiments to be done!

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1 RISING TEMPERatures “I don’t know why I had to come to this camp,” Enzo grumbled to himself as he followed the other campers down the path toward the meeting hall. “I didn’t want to come. Mom and dad made me do this.” He was still in a foul mood when the camp director divided the campers into groups and assigned them a counselor. Enzo’s group was assigned to Joaquin. Joaquin was enthusiastic and ready to start the day. “Okay, everyone, here is our first task,” said the dark-haired young man. “Here at Enviro- Camp, we are lucky. We get to experience nature and the environment first hand. How often do you get to spend two weeks in the Rocky Mountains?” Enzo snorted. A girl standing next to him elbowed him in the ribs. “Shh!” she said. “I’m look- ing forward to this!” Joaquin continued, “For our first experience, we are going for a walk. Later we will come back here, look at some maps, and do some experiments. Okay, let’s go.” He took off at a brisk pace out of the campsite.

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Enzo turned to the girl next to him. “Why did you poke me?” “I thought you needed it,” she said. “You seemed grumpy. This is going to be fun, you know. I’m Molly. Nice to meet you.” Reluctantly, Enzo shook her

ecosystem community of living organ- isms and nonliving things that are found in a specific area global warming rise in global temperatures over the past century and its conse- quences Words to Understand

outstretched hand. “Enzo,” he said. “And I’mnot so sure.Mypar- ents shipped me off to this camp because they think I needed to get out of the city for a few weeks. I would much rather be at home skateboarding with my friends.” The two of them followed Joaquin and the other campers in their group. “Oh, come on.” Molly said. “Give it a chance. I’ve heard great things. I think it will be an adventure.” “Yeah, an adventure in mosquito bites,” Enzo grumbled, slapping at the insect that landed on his arm. Joaquin stopped about a mile from camp in a grove of trees. “Look around you. What do you see?” “Trees,” someone answered. The group giggled nervously. “Yes, trees. But what is it about these trees?” he asked. “Take a close look at them. Go ahead, walk around, touch them. Examine the bark, the roots, the forest floor. Spend some time out there and let’s gather back here in a bit.” The campers wandered through the forest. Molly and Enzo walked together. “I think these trees are dead,” Molly said, looking up at the branches overhead. “Gee, you think?” Enzo said sarcastically, looking up at the grey branches lacking leaves. He stopped. “Listen. I don’t hear any birds, either.” “You’re right,” Molly said. “It’s as if the whole forest is dead.” Enzo and Molly walked around and looked more carefully at the trees. The darkened trees showed evidence of a forest fire. There were also marks indicating that insects had eaten away a lot of the bark and other layers of the tree. Molly also noticed that there wasn’t much vegetation growing anywhere in the area. The ground was packed hard, not soft and spongy as the woods had been closer to the camp. Once Joaquin got the campers back into their group he began to ask questions. “What do you think happened here?” photosynthesis process by which plants use carbon dioxide and energy from the sun to create energy and release oxygen

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“It looks as if there was a forest fire,” replied one camper. Enzo spoke up, “Yeah, but I thought forest fires can be a good thing for a forest. You know, the idea of a fire clearing out the dead brush to make room for the new growth and adding nu- trients to the soil. I thought those were good things.” “I’m impressed, Enzo. You know a lot about forest fires,” said Joaquin. “Yes, under normal circumstances, a forest fire can be very healthy to a forest ecosystem . But something else is going on here.” “You know, I saw a lot of insects hopping around the trees, too,” another camper said. Joaquin nodded. “Scientists have studied these woods for about a decade and found some alarming things. Yes, there are a lot of insects here. Many of these are insects that can harm, not help, the trees. There have been three major fires here in the past twenty years. That’s a lot. And many of these signs point to global warming as a cause.” Molly raised her hand. “Global warming? As in ice sheets melting? How is that affecting our trees here?” Joaquin held up his hand. “That’s not even the biggest question. The bigger question is how does this forest here impact the rest of the world?” The group of students seemed skeptical at this question. Joaquin smiled and went on. “Not that I want to teach you science or anything, but does everyone remember what happens during photosynthesis ?” “I know!” a camper chimed in. “Plants take carbon dioxide out of the air and then use energy from the sun to convert the carbon dioxide to oxygen and energy.” Global Warming or Climate Change? Some are skeptical of the idea of global warming. Scientists point out that it should be called climate change, since warming is only part of the issue. Disbelievers point to the fact that extreme cold snaps and huge win- ter storms batter parts of the country and the world during the winter months. However, scientists explain that colder than usual temperatures and severe winter storms are indeed part of climate change. A phenomenon called Arc- tic Oscillation is the mix of the jet stream and air from the Arctic regions. This movement of the jet stream can bring colder-than-usual temperatures to many northern regions around the globe. It can be super cold, even as we warm!

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Molly looked thoughtful. “Then without the trees here in this forest, there will be more car- bon dioxide in the air.” “And the more carbon dioxide, the warmer the climate,” Enzo concluded. Joaquin smiled again. “This is a simplified, small-scale look at what is happening. Carbon di- oxide is a greenhouse gas, responsible for trapping heat close to Earth’s surface. Carbon dioxide enters the atmosphere when fossil fuels are burned, or when massive forest fires destroy acres and acres of land. Forest fires mean fewer trees which are used to “clean” the atmosphere of car- bon dioxide. It’s a vicious cycle.” The group continued their walk in silence, wondering what the future held.

Try It Yourself

Climate change could result in a rapid melting of the polar ice sheets. If the ice sheet over Greenland melted, for example, sea level—across the plan- et—would rise by an estimated 20 feet (about six meters). If the ice sheet over Antarctica completely melted, sea level would rise 200 feet (about 60 meters)! How much water is really in ice? Try this experiment and find out.

Materials: • paper cup or liquid measuring cup • kitchen scale

• ice cubes • tap water

1. Use the kitchen scale to find the mass of the paper cup or measuring cup. 2. Add water to the cup and find the new mass. 3. Find the mass of 4–5 large ice cubes. 4. Add those to the water. 5. Allow the ice cubes to melt. 6. How much did the mass change? How much water was added to the cup when the ice cubes melted? Was it the same as the amount of water? Or was it more or less?

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the power of recycling 2

“H ey, Enzo!”

Enzo turned as Molly rushed up to him in the cafeteria. “You know,” she said, “you shouldn’t throw that can in the regular garbage. It can be recycled.” She reached into the trash, pulled the can out and then deposited it in the recycle bin next to the trash. Enzo looked at her as if she had lost her mind. “Seriously? Do you think my one little can is going to make that big of a difference? It’s not like I am ruining the Earth single-handedly.” Molly followed him out of the cafeteria. “You sure are grumpy, Enzo. Why is that?”

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“And you sure are nosy.” He turned to look at her. “Okay, I’m sorry. I just didn’t want to come to this camp in the first place. And now there are all these rules and everyone seems to be so into protecting the environment. It’s just not something I’m that interested in.” Molly nodded and said, “Well, maybe you just haven’t had the chance to think about it. Come with me.” Molly and Enzo walked to an area of the camp that was far from the other buildings. There they found Joaquin. He was digging into a large black container with a pitchfork. “Hi Joaquin,” Molly said. “Enzo and I wanted to see if we could help you.” Joaquin stopped digging and stood up. “Great! I could really use some help turning over this compost . And there is a new batch that is ready to be spread on the garden over here.” He gave Molly the pitchfork and motioned to Enzo to follow him. Along the way he ex- plained what was happening. “A couple of years ago, I planted a garden here at the camp. I start- ed a composting effort at the same time. We take the food waste from the cafeteria and turn it into useable fertilizer for the garden.” Enzo stared at the soil Joaquin was spreading between the plants. “You mean that is food?” “Well, not all food. But it is a fair amount of the food waste that is generated in the kitchen. Things like vegetable scraps, eggshells, and the cores or peels from fruits are commonly com- posted. What most people don’t realize is that things like old bread, pretzels, or noodles can be composted, too. Things made out of flour. Coffee grounds, tea bags, spices, and grains can go in there too. You just want to keep things like meat, bones, dairy products, and grease out of the compost. Those things attract animals and maggots and will mess up the nutrients in the com- post.” Enzo squatted down so he was close to the compost. “It doesn’t even stink. I would have thought that it would really smell like rotting fruit or something.” Joaquin shook his head. “Nope. If it is done right, a compost pile really doesn’t smell. Cover- ing it with fresh grass cuttings or hay, burying the fresher waste, and keeping a good flow of air in and out of the pile makes a big difference. That helps keep the fruit flies away, too.” Molly came over to help out. “That’s why we have to separate things in the cafeteria, Enzo. I wanted you to see where the stuff was going.” compost organic material that has been decomposed and used again as fertilizer emissions gases expelled during natural or artificial processes landfill site for the disposal of waste materials Words to Understand

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Enzo looked surprised. “Oh, I had no idea. But what about the stuff you can’t compost?” “Well, there are a lot of different options. Most of the other trash items can be recycled. Cans, plastics, paper, all those can be recycled. This leaves a very small amount of actual trash and it helps keep things with other uses out of landfills .” “And think about this,” Molly said, “I did a research project on recycling last year in school. Twenty recycled cans can be produced with the same amount of energy needed to make only one can from raw materials. And about 80 percent of the glass that makes it into a new glass bottle or jar is recycled glass. So recycling just one glass bottle can make a huge difference!” “I really didn’t know all this. But I am ready to start recycling and composting now,” Enzo declared.

Consider This On average, each person recycles or composts 1.5

pounds (.6 kg) of municipal solid waste each day. This is 1.5 pounds (.6 kg) of waste that does not go to a landfill. But it also saves nearly 3 pounds (1.3 kg) of carbon dioxide emissions . The process of manufactur- ing brand new aluminum cans, glass bottles or cardboard boxes uses en- ergy, which creates carbon dioxide emissions.

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