Homework answers / question archive / AGRI280-M73 (Su21): INTRO ENVIRONMENT

AGRI280-M73 (Su21): INTRO ENVIRONMENT

Sociology

Share With

AGRI280-M73 (Su21): INTRO ENVIRONMENT.. 1. Watch the lecture and read through chapter 1 BEFORE doing this discussion board. There are many benefits to us and our future generation to preserving our environments and ecosystems, however there are always negatives to every positive. Discuss 2 benefits and 2 detriments to making changes in how we do things to preserve and even fix our environment now (20 points). You also need to respond to one of your classmate's ideas for an additional 10 points. Important: Please remember when participating in discussion boards that we MUST be respectful of each other. All rude comments, profanity or otherwise inappropriate comments will be deleted and will result in a grade of 0 points. 2. Research a "local" environmental disaster and tell us all about it on the discussion board. "Local" is very subjective, I would prefer KY/TN/OH/IN areas but if you find something really interesting elsewhere that is fine too. This should be about 150-200 words. Tell us what happened that caused the disaster, what other affects this had on the community, and what was done about it. It does not have to be currently happening. (25 points) Comment on 2 of your classmate's posts. Comments can include how that disaster could have been prevented, other unintended affects on people, animals or the community or anything else you think is pertinent. (20 additional points) Tracking your water usage assignment Since we know that in our country we use as much water as we want, but in many countries, each person lives off 1 gallon or less per person per day... Day 1: Track your water usage for a 24 hour period. Estimate or measure to the best of your ability how much water you use for everything. This is everything from eating/drinking, personal hygiene, outdoors, etc. One way to measure your shower is allow the water to fill the bathtub then use a gallon jug to scoop it out of the tub when you are done. This can be a really fun and eye-opening experience and it is only for 1 day. Add up the total you used for eating, personal hygiene and other. Write a 1 page description that lists everything and how much you used for each thing and then a summary of at least 250 words describing this experience. (worth 50 points) Day 2: See if you can use only 3 gallons of water for the whole day. Write a 1 page description of how you used your 3 gallons, what time you ran out and what changes you would need to make to regularly live on just 3 gallons. (worth 50 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. Water Usage - Discussion Water Usage - Discussion AFTER completing your water usage assignment, share your experiences by posting a 250 word summary of how much water you used, what the hardest thing about the assignment was, what you learned by doing the assignment and where you could make changes in your own life to conserve water. (20 points) This has been a super interesting assignment when I have used it in other classes! Comment on 2 other people's posts. (10 points) Tracking YOUR Wastes Since we know that in our country we use whatever we want and throw it away and never really think about it again........... Day 1: Track all of your wastes for 2 days. Keep a log of literally everything you throw away and what you did with it (trash can, composted it, recycle bin, etc). This is everything from eating/drinking, personal hygiene, outdoors, etc. Also keep track of what the item is (glass, plastic, wood, whatever) and if it was recyclable or not (even if you did not recycle it). This can be a really fun and eye-opening experience. Add up the total number of items you threw away and make a graph of your wastes (plastics, glass etc and how you disposed of them (trash can, recycle bin etc). You are free to be creative. I suggest doing this as an excel spreadsheet and then making a graph inside of excel. You can do one graph or 2. Write a 1 page description of at least 250 words describing this experience. (worth 100 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. YOUR Wastes - Discussion YOUR Wastes - Discussion AFTER completing YOUR waste tracking assignment, post a 250 word summary of what you found out about your habits, how much of the items could have been recycled but weren't, why you chose to dispose of items the way you did and anything else you learned by doing the assignment. If you have any comments on the landfill tour video, you can also share those here. (20 points) The Plastic Problem The Plastic Problem Read the current news articles about the plastic problem and watch the PBS documentary and post your thoughts here. Be sure to demonstrate that you have indeed read the articles and watched the video as well as let us know what your thoughts are! https://www.youtube.com/watch?v=1RDc2opwg0I Plastic has become such a huge problem and yet none of us are really ok with doing anything abo plastic will ultimately be the ruin of the environment. Single use plastics are the worst. Those are gatorade bottles that we open, drink and throw away. That bottle then lasts in the enviroment fo now literally think to myself, am I really willing to drink this in 20 minutes and then throw it away thousands of years? No I really am not- are you? Read the articles in the plastic problem and post your thoughts. Be sure to reply to at least 2 clas An Introduction to Environmental Science © 2011 Pearson Education, Inc. Environmental science • Environmental science: the study of how the natural world works together • Examines cause-and-effect relationships underlying issues and problems that rise from our use of the natural world • Encompasses many disciplines • History, engineering, geology, physics, medicine, biology, sociology, chemistry, agriculture • It is the most multidisciplinary of all sciences © 2011 Pearson Education, Inc. Easter Island once had a prosperous culture © 2011 Pearson Education, Inc. Easter Island: an environmental catastrophe • By 1650, all the trees were gone • The soil washed into the sea • Degraded soil, depleted forest and water resources • Existence became harder • Starvation and disease became epidemic • Without trees, no one could leave the island by boat • The population was down to a few thousand by 1722 • Easter Islanders did not anticipate the consequences of their actions © 2011 Pearson Education, Inc. Lessons from Easter Island • When the following occur: • A society does not care for its environment • Its population increases beyond the capacity of the land and water to provide food for all • Then, its civilization collapses • Other civilizations collapsed when they failed to recognize the constraints of their environment • Mayans, Greeks, Incas, and Romans © 2011 Pearson Education, Inc. China’s environmental problems • Toxic air: China has 16 of the world’s most polluted cities • Sulfur dioxide from coal-burning power plants and stoves • Air pollution kills 750,000 people prematurely each year • Toxic water: China is the cancer capital of the world • Water is grossly polluted with sewage and industrial wastes © 2011 Pearson Education, Inc. The Yellow River turns red © 2011 Pearson Education, Inc. DDT was widely used in 1960’s and dangerous Insert Fig 1-2 DDT sprayed over towns, fields, and marshes killed songbirds, bald eagles, and osprey © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Silent Spring • Rachel Carson’s 1962 book Silent Spring described the environmental effects of DDT − Fish, farm animals, and even people died • Silent Spring was attacked by the chemical and agricultural industries • President Kennedy charged the President’s Science Advisory Committee to study the pesticide problem − The Committee fully supported Carson’s thesis © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. DDT banned • DDT was banned in the U.S. and other industrialized countries in the early 1970s • Rachel Carson died in 1964 • Carson’s legacy lives on: • She is credited with major reforms • She initiated environmental awareness that led to the modern environmental movement • This awareness led to the creation of the EPA © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. The early environmental movement • Has its roots in the late 19th century • Unique, wild aspects of the U.S. were disappearing • Conservation groups were formed • National Audubon Society, National Wildlife Federation, Sierra Club • President Theodore Roosevelt placed 230 million acres under public protection and started the National Parks Service • A national environmental consciousness was stirring © 2011 Pearson Education, Inc. EPA created in 1970 • Congress created the Environmental Protection Agency (EPA) in 1970 • Congress passed laws for pollution control and wildlife protection • The air and water are much cleaner than in the 1960s • Without the environmental movement, our air and water would be a toxic brew © 2011 Pearson Education, Inc. The state of the planet • The world faces four unhealthy global trends (1) Decline of vital ecosystems (2) Increasing population growth (3) Global climate change (4) Loss of biodiversity © 2011 Pearson Education, Inc. The world’s population has exploded © 2011 Pearson Education, Inc. The HDI has increased in most nations Insert Fig 1-4 All but 3 of the 135 countries have a higher HDI than in 1970 © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Global climate change: a serious problem • Global climate change is a current serious problem • Due to accumulation of greenhouse gases • Carbon dioxide is a natural component of the atmosphere • It is required by plants for photosynthesis • It’s important to the Earth’s atmosphere energy system • The greenhouse effect: carbon dioxide absorbs infrared (heat) energy which warms the lower atmosphere © 2011 Pearson Education, Inc. Global temperature and carbon dioxide © 2011 Pearson Education, Inc. Global climate change • Every day we generate 80 million tons of CO2 • By burning 89 million barrels of oil, 340 billion cubic feet of natural gas, and 17 million tons of coal • CO2 concentration is definitely increasing • Overall temperature is increasing • Could this just be a natural cycle? © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Global temperature since 1880 Insert Fig 1-6 Global temperatures have been recorded at thousands of stations around the world © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Intergovernmental Panel on Climate Change (IPCC) • Established by the United Nations in 1988 • It reports its assessment of climate change every 5 years • Input from thousands of experts • Produced convincing evidence that human-induced climate change is already severely affecting global climate • Concluded that future changes could be catastrophic if emissions of greenhouse gases are not controlled • With few exceptions, there is a clear consensus that this is a huge global problem © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Loss of biodiversity • Biodiversity: variability among living organisms and the ecological complexes of which they are part • Causes of biodiversity losses • Conversion of natural land to crops and cities • Pollution • Exploitation for commercial value • Species are hunted, killed, and marketed illegally • Most species are declining in their range and/or population size, especially in the tropics • Vertebrate species have declined by 33% since 1970 © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Risks of losing biodiversity • A biodiverse ecosystem is healthy • It helps maintain natural systems • Enabling them to recover after a disturbance • It provides essential goods and services • Particularly for the poor • Aesthetic and moral arguments for biodiversity • Do we have a moral responsibility to protect and preserve the amazing diversity of life on Earth? © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Three unifying themes to a better future Insert Fig. 1-8 Sustainability, stewardship, and sound science can move us toward a sustainable future © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Sustainable societies • A sustainable society is in balance with the natural world • Continues for generations without depleting resources • Does not produce more pollution than nature can absorb © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Sustainable development is complex • It incorporates equity: meeting the needs of the present while considering future generations • Sustainability means different things to people • Economists are concerned with efficiency and resource use • Sociologists focus on human needs • Ecologists want to save natural systems, live within Earth’s carrying capacity, and deal with pollutants • Agriculturists want to take care of their land to have it for future farming activities © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Sound science • Many environmental issues are so controversial, people are left confused • The scientific method: a way of gaining knowledge • Junk science does not conform to the rigorous methods and practices of legitimate science • Sound science uses the scientific method to understand how the natural world works © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. The scientific method starts with an observation • It is the keystone of scientific discovery • It brings together observations, experimentation and analysis • Not all observations are accurate • As observations are confirmed, they gain status © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Junk science • The media and public often give equal credibility to opposing views on an issue (e.g., global warming) • Junk science: information presented as scientifically valid, but does not conform to the rigors of true science • Special interests call anything that threatens their preferred viewpoint junk science • True junk science takes many forms: • Picking and choosing only results supporting your idea • Politically motivated distortions of information • Publication of results in unreviewed books or journals © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. The Scientific Method © 2011 Pearson Education, Inc. Stewardship • Actions and programs that manage natural resources and human well-being for the common good • Stewards care for something they do not own • The natural world or human culture • They will pass it on to the next generation © 2014 Pearson Education, Inc. © 2011 Pearson Education, Inc. Day 2 Information to complete assignment. Your Responsibilities: 1. 2. 3. 4. 5. Watch the lecture on Living Things and Ecosystems Printable version of Living Things and Ecosystems Printable version of Living Things and Ecosystems - Alternative Formats lecture for note taking (slides may be different than video but content is the same). Read/skim through chapters 3,4,5. If I did not cover sections from the chapter in the lecture, then you do not have to worry about reading those sections. Take the quiz over the reading, using your book. Participate in the discussion board about a local environmental disaster. Due Saturday, 5/15 8:00am CST. Local Environmental Disasters - Discussion Local Environmental Disasters - Discussion Research a "local" environmental disaster and tell us all about it on the discussion board. "Local" is very subjective, I would prefer KY/TN/OH/IN areas but if you find something really interesting elsewhere that is fine too. This should be about 150-200 words. Tell us what happened that caused the disaster, what other affects this had on the community, and what was done about it. It does not have to be currently happening. (25 points) Comment on 2 of your classmate's posts. Comments can include how that disaster could have been prevented, other unintended affects on people,animals or the community or anything else you think is pertinent. (20 additional points) Day 3. Your Responsibilities: 1. Watch the lecture video on Water Issues. 2. Printable version of Water Issues Printable version of Water Issues - Alternative Formats lecture for note taking (slides may be different than video but content is the same). 3. Read/review Chapter 10 and 20. 4. Do water usage assignments-2 parts. (Don't wait until the last minute to do this as the results from this are used for your discussion board.) 5. Read this article on real life water usage limits. article on real life water usage limits. Alternative Formats 6. Report your results of water usage assignment on discussion board. Tracking your water usage assignment Since we know that in our country we use as much water as we want, but in many countries, each person lives off 1 gallon or less per person per day... Day 1: Track your water usage for a 24 hour period. Estimate or measure to the best of your ability how much water you use for everything. This is everything from eating/drinking, personal hygiene, outdoors, etc. One way to measure your shower is allow the water to fill the bathtub then use a gallon jug to scoop it out of the tub when you are done. This can be a really fun and eye-opening experience and it is only for 1 day. Add up the total you used for eating, personal hygiene and other. Write a 1 page description that lists everything and how much you used for each thing and then a summary of at least 250 words describing this experience. (worth 50 points) Day 2: See if you can use only 3 gallons of water for the whole day. Write a 1 page description of how you used your 3 gallons, what time you ran out and what changes you would need to make to regularly live on just 3 gallons. (worth 50 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. Water Usage - Discussion Water Usage - Discussion AFTER completing your water usage assignment, share your experiences by posting a 250 word summary of how much water you used, what the hardest thing about the assignment was, what you learned by doing the assignment and where you could make changes in your own life to conserve water. (20 points) This has been a super interesting assignment when I have used it in other classes! Comment on 2 other people's posts. (10 points) • Day 4: • • • • Read through chapters 11 and 21. Watch the lecture video Land and Pollution. Printable version of Land and Pollution Printable version of Land and Pollution - Alternative Formats lecture for note taking (slides may be different than video but content is the same). Watch the Video Field Trip- tour of a landfill- I know it sounds boring but it isn't! Complete the "Tracking YOUR wastes" assignment. (Be sure to do this at the beginning of the week so that you will have time to post to the discussion board.) Read the articles on The Plastic Problem and post on the dicussion board. • Tracking YOUR Wastes • • Since we know that in our country we use whatever we want and throw it away and never really think about it again........... Day 1: Track all of your wastes for 2 days. Keep a log of literally everything you throw away and what you did with it (trash can, composted it, recycle bin, etc). This is everything from eating/drinking, personal hygiene, outdoors, etc. Also keep track of what the item is (glass, plastic, wood, whatever)and if it was recyclable or not (even if you did not recycle it). This can be a really fun and eye-opening experience. Add up the total number of items you threw away and make a graph of your wastes (plastics, glass etc and how you disposed of them (trash can, recycle bin etc). You are free to be creative. I suggest doing this as an excel spreadsheet and then making a graph inside of excel. You can do one graph or 2. Write a 1 page description of at least 250 words describing this experience. (worth 100 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. • YOUR Wastes - Discussion YOUR Wastes - Discussion AFTER completing YOUR waste tracking assignment, post a 250 word summary of what you found out about your habits, how much of the items could have been recycled but weren't, why you chose to dispose of items the way you did and anything else you learned by doing the assignment. If you have any comments on the landfill tour video, you can also share those here. (20 points) Comment on 2 other people's posts. (10 points) The Plastic Problem The Plastic Problem Read the current news articles about the plastic problem and watch the PBS documentary and post your thoughts here. Be sure to demonstrate that you have indeed read the articles and watched the video as well as let us know what your thoughts are! Plastic has become such a huge problem and yet none of us are really ok with doing anything abo plastic will ultimately be the ruin of the environment. Single use plastics are the worst. Those are gatorade bottles that we open, drink and throw away. That bottle then lasts in the enviroment fo now literally think to myself, am I really willing to drink this in 20 minutes and then throw it away thousands of years? No I really am not- are you? Read the articles in the plastic problem and post your thoughts. Be sure to reply to at least 2 clas Due Saturday, 5/15 8:00am CST. Day 2 Information to complete assignment. Your Responsibilities: 1. 2. 3. 4. 5. Watch the lecture on Living Things and Ecosystems Printable version of Living Things and Ecosystems Printable version of Living Things and Ecosystems - Alternative Formats lecture for note taking (slides may be different than video but content is the same). Read/skim through chapters 3,4,5. If I did not cover sections from the chapter in the lecture, then you do not have to worry about reading those sections. Take the quiz over the reading, using your book. Participate in the discussion board about a local environmental disaster. Due Saturday, 5/15 8:00am CST. Local Environmental Disasters - Discussion Local Environmental Disasters - Discussion Research a "local" environmental disaster and tell us all about it on the discussion board. "Local" is very subjective, I would prefer KY/TN/OH/IN areas but if you find something really interesting elsewhere that is fine too. This should be about 150-200 words. Tell us what happened that caused the disaster, what other affects this had on the community, and what was done about it. It does not have to be currently happening. (25 points) Comment on 2 of your classmate's posts. Comments can include how that disaster could have been prevented, other unintended affects on people,animals or the community or anything else you think is pertinent. (20 additional points) Day 3. Your Responsibilities: 1. Watch the lecture video on Water Issues. 2. Printable version of Water Issues Printable version of Water Issues - Alternative Formats lecture for note taking (slides may be different than video but content is the same). 3. Read/review Chapter 10 and 20. 4. Do water usage assignments-2 parts. (Don't wait until the last minute to do this as the results from this are used for your discussion board.) 5. Read this article on real life water usage limits. article on real life water usage limits. Alternative Formats 6. Report your results of water usage assignment on discussion board. Tracking your water usage assignment Since we know that in our country we use as much water as we want, but in many countries, each person lives off 1 gallon or less per person per day... Day 1: Track your water usage for a 24 hour period. Estimate or measure to the best of your ability how much water you use for everything. This is everything from eating/drinking, personal hygiene, outdoors, etc. One way to measure your shower is allow the water to fill the bathtub then use a gallon jug to scoop it out of the tub when you are done. This can be a really fun and eye-opening experience and it is only for 1 day. Add up the total you used for eating, personal hygiene and other. Write a 1 page description that lists everything and how much you used for each thing and then a summary of at least 250 words describing this experience. (worth 50 points) Day 2: See if you can use only 3 gallons of water for the whole day. Write a 1 page description of how you used your 3 gallons, what time you ran out and what changes you would need to make to regularly live on just 3 gallons. (worth 50 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. Water Usage - Discussion Water Usage - Discussion AFTER completing your water usage assignment, share your experiences by posting a 250 word summary of how much water you used, what the hardest thing about the assignment was, what you learned by doing the assignment and where you could make changes in your own life to conserve water. (20 points) This has been a super interesting assignment when I have used it in other classes! Comment on 2 other people's posts. (10 points) • Day 4: • • • • Read through chapters 11 and 21. Watch the lecture video Land and Pollution. Printable version of Land and Pollution Printable version of Land and Pollution - Alternative Formats lecture for note taking (slides may be different than video but content is the same). Watch the Video Field Trip- tour of a landfill- I know it sounds boring but it isn't! Complete the "Tracking YOUR wastes" assignment. (Be sure to do this at the beginning of the week so that you will have time to post to the discussion board.) Read the articles on The Plastic Problem and post on the dicussion board. • Tracking YOUR Wastes • • Since we know that in our country we use whatever we want and throw it away and never really think about it again........... Day 1: Track all of your wastes for 2 days. Keep a log of literally everything you throw away and what you did with it (trash can, composted it, recycle bin, etc). This is everything from eating/drinking, personal hygiene, outdoors, etc. Also keep track of what the item is (glass, plastic, wood, whatever)and if it was recyclable or not (even if you did not recycle it). This can be a really fun and eye-opening experience. Add up the total number of items you threw away and make a graph of your wastes (plastics, glass etc and how you disposed of them (trash can, recycle bin etc). You are free to be creative. I suggest doing this as an excel spreadsheet and then making a graph inside of excel. You can do one graph or 2. Write a 1 page description of at least 250 words describing this experience. (worth 100 points) NOTES: Please be very descriptive. Leaving out amount or detail will result in lost points. This is worth 100 points total so it is well worth your time and effort. Also, do not wait until the last minute to do this assignment because you also have to use this information to post to the discussion board. • YOUR Wastes - Discussion YOUR Wastes - Discussion AFTER completing YOUR waste tracking assignment, post a 250 word summary of what you found out about your habits, how much of the items could have been recycled but weren't, why you chose to dispose of items the way you did and anything else you learned by doing the assignment. If you have any comments on the landfill tour video, you can also share those here. (20 points) Comment on 2 other people's posts. (10 points) The Plastic Problem The Plastic Problem Read the current news articles about the plastic problem and watch the PBS documentary and post your thoughts here. Be sure to demonstrate that you have indeed read the articles and watched the video as well as let us know what your thoughts are! Plastic has become such a huge problem and yet none of us are really ok with doing anything abo plastic will ultimately be the ruin of the environment. Single use plastics are the worst. Those are gatorade bottles that we open, drink and throw away. That bottle then lasts in the enviroment fo now literally think to myself, am I really willing to drink this in 20 minutes and then throw it away thousands of years? No I really am not- are you? Read the articles in the plastic problem and post your thoughts. Be sure to reply to at least 2 clas Due Saturday, 5/15 8:00am CST. Ecosystems and Living Things Parts of Chapter 3, 4, 5 The hierarchy of life Life consists of a hierarchy of complex systems © 2014 Pearson Education, Inc. Biomes • Ecosystems having similar vegetation and climactic conditions 1. Temperate deciduous forest: rainfall of 72– 200 cm (30–80 in.)/yr 2. Grassland (prairie) biome: rainfall is less or seasonal 3. Desert biome: rainfall is less than 25 cm (10 in.)/yr 4. Permafrost: permanently frozen subsoil 5. Tundra biome: has grasses, clover, and other small plants that grow above the permafrost World distribution of the major terrestrial biomes Environmental factors affect organisms • Organisms live in the environment with physical, chemical, and biological (biotic) or abiotic factors • Resource: any factor consumed by organisms – Water, nutrients, light, oxygen, food, space – We consume resources from ecosystems too! © 2014 Pearson Education, Inc. Survival depends on optimum levels of factors Individuals living in an area that is above or below the optimum level for a certain factor may die. © 2014 Pearson Education, Inc. Habitat and niche • Habitat: place defined by the plant community and physical environment— where a species is adapted to live – A deciduous forest, swamp, hole in a tree • Niche: the sum of all conditions and resources under which a species can live – What the animal eats, where it feeds and lives, how it responds to abiotic factors • Species coexist in an area but have separate niches Four spheres of the Earth? The biosphere interacts with, and depends on, the other three spheres. © 2014 Pearson Education, Inc. The Atmosphere • Atmosphere: the thin layer of gases separating Earth from outer space – Oxygen (O2), nitrogen (N2), carbon dioxide (CO2) • Plants take in carbon dioxide through leaves • Animals take in oxygen through lungs, gills, or skin © 2014 Pearson Education, Inc. The Atmosphere continued The Hydrosphere • All the water in oceans, rivers, ice, groundwater • Liquid water is essential for living things • Water is constantly cycling through melting and evaporation • 71% of earth is covered in water • 96% of the water is in ocean © 2014 Pearson Education, Inc. The lithosphere • The land! • Mineral: a naturally occurring solid made by geologic processes – Crystalline structure of a chemical composition • Rocks: made of small crystals of two or more minerals • Soil: particles of many different minerals © 2014 Pearson Education, Inc. Interactions between the spheres © 2014 Pearson Education, Inc. Producers and Consumers • Producers: Usually plants © 2014 Pearson Education, Inc. Producers and Consumers cont. Consumers get food from others © 2014 Pearson Education, Inc. Consumers • Divided into subgroups according to their food source – Primary consumers (herbivores): feed on producers – Secondary consumers: feed on primary consumers • Carnivores: secondary or higher-order meat eaters • Omnivores: feed on both plants and animals • Animals can occupy various levels, depending on the food Chapter 4- Populations and Communities Golden frogs: a species on the edge • The golden frog is a national symbol of Panama • Populations very low due to: – habitat loss and overcollection for the pet trade – an introduced chytrid fungus deadly to amphibians • To prevent extinction, conservationists collected all amphibians from the wild in Panama – removing the last known population of golden frogs in the world © 2014 Pearson Education, Inc. Dynamics of natural populations • Populations grow with births and immigration • They decline with deaths and emigration (Births + Immigration) – (Deaths + Emigration) = Change in population number Increasing populations decrease human well-being • Today, there are more than 7.3 billion persons – – – – The population grew by 2 billion in the last 25 years 75 million persons are added each year By 2050, there could be 9.1 billion people They will have to be fed, clothed, housed, and have jobs • Most population increases will be in developing countries – 985 million experience extreme poverty ($1 a day) – Over 800 million are malnourished – 6 million preschoolers die each year of hunger and malnutrition What factors limit population size? • Population density: number of individuals in a given area • Density-dependent factor: increases with increased population density – Disease, predation, food shortages • Density-independent factor: its effects are independent of the density of the population – Spring freeze, fire, volcanic eruption, tsunami © 2014 Pearson Education, Inc. Regulating a population’s size • Only density-dependent factors can regulate a population (keep it in equilibrium) – Predation – Scarcity of food – Parasites – Diseases – Competition © 2014 Pearson Education, Inc. Community Interactions • Relationships between species may be positive (helpful), negative (harmful), or neutral for each species • • • • Predation: one member benefits, the other is harmed (+−) Competition: both species are harmed (−−) Mutualism: both species benefit (++) Commensalism: one benefits, the other is not affected (+0) © 2014 Pearson Education, Inc. Predator-prey relationships Insert Fig. 4-7 © 2014 Pearson Education, Inc. Mutualistic relationships (++) Insert Fig. 4-14 a,b In a mutualistic relationship both species benefit, such as this bee and flower or the lichen’s fungus and alga © 2014 Pearson Education, Inc. Commensalism (+0) This water buffalo is not harmed by the cattle egret, but the cattle egret benefits when insects are stirred up by the buffalo © 2014 Pearson Education, Inc. Insert Fig. 4-15 Sea otters are a keystone species Insert Fig. 4-9 Sea otters eat sea urchins, thereby protecting kelp forests and many other species © 2014 Pearson Education, Inc. Natural Selection • Survival of the fittest: one of the forces in nature leading to changes in a species – Those individuals in a competing group that can survive and reproduce demonstrate superior fitness to the environment • All environmental stress is a selective pressure – Individuals who survive that stress and reproduce have the genetic endowment to better cope with their environment Invasive species can destroy natives Insert Fig. 422a Insert Fig. 422b Mice and rats brought to islands by ships prey on native species—removal of these rodents can help restore the native species © 2014 Pearson Education, Inc. Introduced plant species harm others Insert Fig. 423 Kudzu, a vine introduced to control erosion and for cattle fodder, occupies over 7 million acres of southern U.S. forests © 2014 Pearson Education, Inc. Balance of Ecosystems • Population regulation comes from complex interactions among members community • Organisms in each ecosystem have specific relationships – Introduced species don’t fit into these relationships • Removal of any one species will affect all others in positive and/or negative ways. © 2014 Pearson Education, Inc. Chapter 5 Disturbance of Ecosystems Food webs connect food chains Insert Fig. 5-2a Insert Fig. 5-2b Food chains are interconnected into more complex food webs © 2014 Pearson Education, Inc. Trophic categories of organisms Insert Fig. 5-3 Living organisms are categorized based on how they get their energy © 2014 Pearson Education, Inc. A grassland food chain Insert Fig. 5-4 © 2014 Pearson Education, Inc. A detritus food web Insert Fig. 5-5 Decomposers break down dead organic matter © 2014 Pearson Education, Inc. Ecosystems are complex systems • Ecosystems respond to disturbances such as volcanoes, fires, volcanoes, and humans • Humans rely completely on ecosystems – We assign value to ecosystem goods and services • But ecosystem sustainability is being severely threatened by human use © 2014 Pearson Education, Inc. The decline of ecosystems • Ecosystems support human life and economies with goods and services • Humans are depleting groundwater, degrading soils, overfishing, and depleting forests • The world economy depends on renewable resources – For fresh water, food, fuel, wood, leather, furs, etc. – For raw materials for fabrics, oils and alcohols, etc. • Agriculture, forestry, and fishing are responsible for 50% of all jobs worldwide! Disturbance/Stress • Anything can cause ecosystem disturbance • Sometimes these are natural – Hurricanes – Lighting causes a fire • Sometimes these are man-made • Either type can be positive or negative Primary succession on bare rock Insert Fig. 5-14 © 2014 Pearson Education, Inc. Secondary succession in an abandoned field Insert Fig. 5-15 © 2014 Pearson Education, Inc. Aquatic succession of a lake Insert Fig. 5-16 © 2014 Pearson Education, Inc. Natural ecosystems give way to development The border of Haiti and the Dominican Republic Resilience • Resilience: the ability of an ecosystem to return to normal functioning after a disturbance – Helps maintain ecosystem sustainability – Replenishment of nutrients, regrowth of plants But resilience has its limits – A badly degraded ecosystem can’t carry out its original functions © 2014 Pearson Education, Inc. Resilience mechanisms Insert Fig. 5-19 © 2014 Pearson Education, Inc. Why it matters if ecosystems are changed • Ecosystems provide valuable services to humans and other species – Flood control, maintaining soil, absorbing CO2 • Human actions tend to lower ecosystem services – We use up resources faster than they are produced – Or we totally destroy an ecosystem for development Can ecosystems be restored? • Humans have the capacity to restore ecosystems – In many cases, stopping abuse restores the area • Humans can speed up the process by seeding and planting vegetation and reintroducing animals • Some sites may take intensive efforts by restoration ecologists • Why should we restore ecosystems? – For aesthetic reasons, human use, to preserve our earth © 2014 Pearson Education, Inc. Attitudes toward nature stem from values • Not everyone agrees on types of protection for nature • Some want wildlife protected for hunting – Others feel hunting should be banned • People in developing countries use wildlife and other natural products for food or money What does the future hold? • Human population growth and rising consumption will challenge ecosystem sustainability • There is unprecedented pressure on Earth to provide goods and services – Feed more people – More people need more houses © 2014 Pearson Education, Inc. The Millennium Assessment shows: • Continuing problems that of overfishing, climate change, deforestation • Humans have caused a huge wave of species extinctions • Conservation succeeds when local people are involved • Protection of natural assets requires coordinated efforts • We are living off the future—an unsustainable situation © 2014 Pearson Education, Inc. Water Issues Parts of Chapters 10 and 20 © 2011 Pearson Education, Inc. Aral Sea 1989 to 2014 © 2011 Pearson Education, Inc. Water: a vital resource • Water is fundamental to life • Earth is flooded with water • Covering 75% of the Earth’s surface • 97% of all water is salt water (oceans, seas) • Fresh water: contains < 0.1% (1,000 ppm) salt • 67% of fresh water is bound up in ice caps and glaciers • Only 0.77% of all water is in lakes, wetlands, rivers, groundwater, biota, soil, and the atmosphere • Evaporation and precipitation cycle water through the solar-powered hydrologic cycle © 2011 Pearson Education, Inc. Earth’s water © 2011 Pearson Education, Inc. The hydrologic cycle © 2011 Pearson Education, Inc. Yearly water balance in the hydrologic cycle © 2011 Pearson Education, Inc. Condensation © 2011 Pearson Education, Inc. Climate change affects the water cycle • Evaporation increases with a warmer climate • A wetter atmosphere increases precipitation and floods • More hurricanes and droughts • Water-stressed areas will get less water • The greater volume of warm water, along with melting ice and glaciers, raises sea levels • Affecting ocean currents and 630 million people © 2011 Pearson Education, Inc. Cleared land affects the hydrologic cycle • Removing vegetation causes a sudden influx of water into rivers and streams • Causing floods, pollutants from erosion • Resulting in dry, barren, lifeless streambed • Wetlands also store and release water • Destruction leads to flooding and polluted waterways • Wetlands dry up during droughts © 2011 Pearson Education, Inc. Types of Fresh Water • Ground water-Precipitation that soaks into the ground (infiltration) • Aquifer is ground water found in many layers of rock under the surface • Surface water- ponds, lakes, streams, rivers, etc. on the Earth’s surface • Watershed: all the land area contributing to a stream or river © 2011 Pearson Education, Inc. Impervious surfaces Roofs, roads, and parking lots decrease the water that goes into the soil and recharges groundwater © 2011 Pearson Education, Inc. Freshwater is a renewable resource • Streams, rivers, ponds, lakes, swamps, estuaries, groundwater, bays, oceans, and atmosphere contain water • Water is used for drinking, industries, irrigation, energy, transportation, recreation, waste processing, habitats • Humans have constructed huge infrastructures to control water • Dams, canals, reservoirs, aqueducts, sewer systems © 2011 Pearson Education, Inc. Sources of water • 37% of domestic water comes from groundwater sources • Rural people in developing nations get water where they can • Wells, rivers, lakes, rainwater • Women often have to walk long distances to get water • Water in developing nations is often polluted with waste • 1.1 billion people use polluted water • 1.6 million (mostly children) die each year © 2011 Pearson Education, Inc. Water in developed and developing nations • Water in developing countries is costly or inaccessible • They lack access to safe drinking water and sanitation • People die from waterborne diseases © 2011 Pearson Education, Inc. Differences in availability © 2011 Pearson Education, Inc. Water in the developing world © 2011 Pearson Education, Inc. Water in the developing world (cont.) In many areas of the developing world, water sources are often contaminated with pathogens and other pollutants © 2011 Pearson Education, Inc. Regional usage of water © 2011 Pearson Education, Inc. What are major uses of water? • Worldwide, the largest use is for irrigation • Then industry and direct human use • Use varies by region, depending on: • Natural precipitation and degree of development • Most increases in withdrawal are due to agriculture • Irrigation uses 65% of freshwater in the U.S. • 20% of U.S. domestic water comes from groundwater • 80% comes from surface water (rivers, lakes, reservoirs) © 2011 Pearson Education, Inc. Water poverty index Patterns of water availability involve precipitation and human uses © 2011 Pearson Education, Inc. U.S. trends in population and freshwater withdrawals Since 1980, Americans have used less water, even though the population increased © 2011 Pearson Education, Inc. Developed nations collect, treat, and distribute water • Larger municipalities rely mostly on surface water • Dams are used to generate power, and for recreation, flood control, and irrigation • Water used in homes, schools, industries is first piped to a treatment plant • Wastewater is collected by a sewage system and treated before being released downstream • Water is reused many times on major rivers • Smaller public drinking-water systems depend on groundwater, which is purified by percolation © 2011 Pearson Education, Inc. Water stewardship: supply and public policy • The water cycle can meet human needs for fresh water • But water is often not located where it is most needed, resulting in persistent water scarcity • The developing world lacks infrastructure (wells, watertreatment systems, dams) to capture and distribute water • Increasing populations create increasing water demand • To eradicate hunger, water use will have to double • An unacceptable and impossible scenario • Only five possibilities exist to meet future water needs © 2011 Pearson Education, Inc. Is bottled water the answer? • Half of Americans use bottled water • In 2008, we used 50 billion bottles, costing $34 billion • Using bottled water has negative effects • Bottling can occur where locals want to use the water • In 2009, the courts decided Nestle Waters, North America, could not pump 400 gallons/minute • Bottled water uses lots of energy for plastic bottles and transportation • Bottled water may be good for emergencies • But not as a source of drinking water © 2011 Pearson Education, Inc. Impacts of falling water tables • The simplest indication that groundwater withdrawals exceed recharge rates • Falling water tables • Common throughout the world • Decreased crop production • Diminishing surface water • Dries up wetlands, springs and seeps, streams, rivers © 2011 Pearson Education, Inc. Some aquifers are nonrenewable • 99% of all freshwater is in aquifers • Nonrenewable groundwater: more than 75% of aquifers have recharge rates of centuries • Percolation replenished renewable groundwater • Is vulnerable to variations in precipitation • We are tapping large, but limited, natural reservoirs • Sustainability depends on balancing withdrawal rates with recharge rates • Most groundwater in arid regions has no recharge • It must be considered nonrenewable, like oil © 2011 Pearson Education, Inc. Exploitation of an aquifer Water from the Ogallala has made the arid part of the U.S. into productive farmland, using center-pivot irrigation—but this is going to end © 2011 Pearson Education, Inc. 5 ways to combat water shortages • • • • • Build more dams Use more groundwater Desalination Use less water Develop crops that can grow with less water © 2011 Pearson Education, Inc. Number of dams in the U.S. Each point represents a dam; the colors tell the height © 2011 Pearson Education, Inc. Dams have enormous impacts • Habitats (waterfalls, rapids, fish runs) are lost • Diversions deprive the river of water downstream from the dam • Fish and other aquatic organisms are impacted • Wildlife is adversely affected (e.g., food chains) • Wetlands dry up, and waterfowl and wildlife die • Fish (e.g., salmon) cannot swim upstream to spawn or downstream to return to the ocean • Even with fish ladders to help them pass the dams • Juvenile salmon suffer 95% mortality going to sea © 2011 Pearson Education, Inc. Desalting seawater • Oceans are an inexhaustible source of water • Desalination: desalting of seawater for domestic use • 13,000 desalination plants in 120 countries • Smaller plants use microfiltration (reverse osmosis [RO]) • Water is forced through a fine membrane to remove salt • Large plants use distillation (evaporation and condensation) • Waste heat from power plants may be used • Desalination costs two to four times what most U.S. people pay • Desalinized water costs about $2 for 1,000 gallons © 2011 Pearson Education, Inc. Tampa Bay leads the way in the U.S. • The Tampa Bay seawater desalination plant was completed in 2008 • • • • The first U.S. plant built for a primary water source It uses salty cooling water from a power plant It produces 25 million gallons per day (MGD) It costs $2.50/1,000 gallons (groundwater = $1/1,000 gallons) • Most people in the U.S. can afford desalinized water • But costs are too high for most agricultural use • The world’s largest plant is in Arab • It produces 215 MGD (2,500 gallons/second) © 2011 Pearson Education, Inc. Desalination plant © 2011 Pearson Education, Inc. Using less water • People in developing nations use 1 gallon/person/day for all their needs, including cooking and washing • A person in the U.S. uses 100 gal per day • Indirect uses (irrigation) increases use 1,000 gal per person per day • The rate of water use has dropped because of conservation © 2011 Pearson Education, Inc. Municipal systems • Each person in a modern home uses 100 gallons/day • Mostly for washing and removing wastes (flushing toilets, taking showers, doing laundry) • Conservation has been presented as “save the environment” • This does not work • It will be expensive and impossible to get more water through traditional reservoirs and wells • The only practical alternative is to save water © 2011 Pearson Education, Inc. A flush world • In 1997 it became illegal to sell 6-gallon commodes • New toilets use 1.6 gallons or even less water • 50 million U.S. low-flow toilets save 600 million gallons/day • It is wasteful to use high-quality water to water lawns or flush toilets • Gray water: slightly dirtied water from sinks, showers, tubs, and laundry tubs • Used in toilets, watering lawns, washing cars © 2011 Pearson Education, Inc. Conserving water: agriculture • Agriculture is the largest user of fresh water • 40% of crops are grown in irrigated soil • Current flood or center-pivot irrigation wastes huge amounts of water • Through evaporation, percolation, runoff • The surge flow method uses computers to control release of water • The drip irrigation method uses pipes with holes to drip water at the base of each plant • Saves water, retards salinization, increases yields © 2011 Pearson Education, Inc. Drip irrigation © 2011 Pearson Education, Inc. National water policy • The U.S. has not addressed water resources and needs with a national policy • The Clean Water Act authorizes the Environmental Protection Agency (EPA) to oversee water quality • But not quantity • Most water policy decisions are made at the local and regional levels • The last water policy report was in 1950 • The U.S. needs a water policy to collect data on water resources and problems and issue recommendations © 2011 Pearson Education, Inc. Chapter 20- Water Pollution © 2011 Pearson Education, Inc. An introduction to water pollution © 2011 Pearson Education, Inc. The 2011 Gulf of Mexico dead zone Each year, oxygen disappears from thousands of square miles of ocean water—in 2011, the dead zone was almost as large as New Jersey © 2011 Pearson Education, Inc. Excess nitrogen leads to oxygen depletion • Abundant nitrogen promotes growth of phytoplankton (photosynthetic microorganisms) • Zooplankton (microscopic animals) eat phytoplankton • These dead organisms are eaten by bacteria, which consumes oxygen • Dead zones last from May to September • Until cold weather mixes the water • The gulfs $2.8 billion fishery was affected • Congress passed the 1998 Harmful Algal Bloom and Hypoxia Research and Control Act © 2011 Pearson Education, Inc. Fighting the gulf’s hypoxia • An interagency task force’s 2000 report confirmed the nitrogen-dead zone relationship • Options to reduce nitrogen: use less fertilizer and restore/promote nitrogen and denitrification processes • An action plan to reduce the size of the hypoxic area by 2015 has not worked • The latest (2008) action plan recommends 45% reduction in nitrogen and phosphorus • The USDA is spending $320 million on conservation • Coastal dead zones are doubling every decade © 2011 Pearson Education, Inc. Water pollution becomes huge problem • Early in the Industrial Revolution chemicals and sewage were dumped directly into U.S. waterways • Contaminating drinking water and causing disease • In the late 1800s, Pasteur and others showed that sewage-borne bacteria caused infectious diseases • Cities implemented sewers and toilets • Receiving waters became cesspools • Water became unfit for any recreational use • Health problems were not seen as being caused by pollution but as the price of progress © 2011 Pearson Education, Inc. The Cuyahoga River on fire In 1969, the Cuyahoga River caught on fire due to flammable industrial sources © 2011 Pearson Education, Inc. Legislation protecting water • The Federal Water Pollution Control Act of 1948 • The first federal action regarding water pollution • The Clean Water Act of 1972 (CWA) • Passed by Congress in response to public outrage about polluted water • Charged the EPA with restoring and maintaining the chemical, physical, and biological integrity of waters • One of the most effective environmental laws enacted © 2011 Pearson Education, Inc. Water pollution: sources and types • Point-source pollution: easy to identify, monitor, and regulate • Factories, sewage systems, power plants, underground coal mines, oil wells • Nonpoint-source pollution: poorly defined and scattered • Agricultural runoff, storm-water runoff (streets, parking lots, lawns), atmospheric deposition • Strategies to control water pollution • Reduce/remove the source: best for nonpoint sources • Treat the water before release: best for point sources © 2011 Pearson Education, Inc. Point and nonpoint sources © 2011 Pearson Education, Inc. Pathogens • Pathogens: disease-carrying bacteria, viruses, parasites • Found in human and animal excrement • Major epidemics have been caused by pathogens in water • Cholera, Typhoid fever, dysentary, Giardia • Public-health measures prevent diseases • Purification and disinfection of public water supplies • Sanitary collection and treatment of wastes © 2011 Pearson Education, Inc. The Ganges River in India © 2011 Pearson Education, Inc. Human Wastes © 2011 Pearson Education, Inc. Sanitation = good medicine • Good health is mostly a result of prevention of disease through public-health measures • One billion lack clean drinking water • 2.5 billion have poor or no sewage treatment • 2 million/year die from waterborne diseases • The Millennium Development Goal 7 is to halve, by 2015, proportion of people without clean water or sanitation © 2011 Pearson Education, Inc. Worldwide distribution of improved sanitation © 2011 Pearson Education, Inc. Organic wastes • Organic matter: human and animal wastes • Leaves, grass, trash, etc. • Most (except plastic and some synthetic chemicals) is biodegradable • Bacteria and detritus feeders consume organic matter and oxygen • Water holds much less dissolved oxygen (DO) than air • Cold water holds more DO (10 ppm) • Even a little organic matter can deplete water’s DO • Bacteria consuming organic matter keep the DO low © 2011 Pearson Education, Inc. Chemical pollutants • Inorganic chemicals: heavy metals (lead, mercury, arsenic, nickel), acids from mine drainage or precipitation • Road salts used to melt ice and snow • Organic chemicals: petroleum, pesticides • Industrial chemicals: polychlorinated biphenyls (PCBs), cleaning solvents, detergents • Many chemicals are toxic at very low levels • Biomagnification: chemicals become concentrated when going up the food chain • Higher concentrations change water chemistry © 2011 Pearson Education, Inc. Acid mine drainage © 2011 Pearson Education, Inc. Sediments • Land weathering and storms wash sediments into water • Erosion from farms, deforestation, overgrazing, construction, mining, roads increases sedimentation • Clear water supports complex food webs • Organisms attach to rocks or hide behind them to prevent washing downstream • Clay and humus make water muddy • Reducing light penetration and photosynthesis • Settled material coats everything, reducing photosynthesis • Smothering gills, feeding structures, and eggs © 2011 Pearson Education, Inc. Stream ecosystem with low bed load © 2011 Pearson Education, Inc. Impact of sediment on streams and rivers © 2011 Pearson Education, Inc. Nutrients • Nutrients: inorganic materials that are essential for plants • Phosphorus and nitrogen: the two most important nutrients • Nutrients become pollutants when they stimulate undesirable plant growth in water • Point sources: untreated or poorly treated sewage outfalls • Particularly in developing countries • Nonpoint sources: agriculture (fertilizers, manure, crops, irrigation water), lawns/gardens, golf courses, drains © 2011 Pearson Education, Inc. Water quality standards • Many pollutants are in water only because of humans • Pesticides, solvents, detergents • Others occur naturally and become a problem under certain conditions • Nutrients, sediments • Pollution: any quantity that is harmful to human health or the environment © 2011 Pearson Education, Inc. Drinking water standards • Safe Drinking Water Act (SDWA) • 94 contaminants • Presented as maximum contaminant levels (MCLs) • Arsenic: a known human carcinogen occurring naturally in groundwater • Drinking water’s MCL was 50 μg/L (1 μg/L = 1 ppb) • EPA lowered it to 10 μg/L • Total Maximum Daily Load (TMDL) program: evaluates all sources (mainly nonpoint) of pollutants • Includes the water’s ability to assimilate the pollutant • 92% of U.S. people’s drinking water meets drinking water standards © 2011 Pearson Education, Inc. Wastewater treatment and management • Facilities were built to treat sewage-polluted water • 1900: the first U.S. wastewater treatment plants were built • Heavy rains overflowed the plants and carried raw sewage to waterways • Regulations require installation of two systems • Storm drains: collect and drain precipitation runoff • Sanitary sewers: receive and treat wastewater (sinks, tubs, toilets) from homes and buildings • Through the 1970s many areas still had untreated wastes • Increasing pollution drove passage of the CWA © 2011 Pearson Education, Inc. Pollutants in raw wastewater • Raw wastewater comes from toilets and all other drains • 99.9% water, 0.1% waste • 150–200 gallons/person/day • 10,000 people produce 1.5–2 million gallons/day • With the addition of storm water, raw wastewater is diluted even more © 2011 Pearson Education, Inc. Types of pollutants in wastewater • Debris and grit: rags, plastic, sand, gravel • Flushed down toilets or in storm drains • Particulate organic matter: fecal matter, food wastes, toilet paper • Fine particles of organic material, bacteria, urine, soaps, detergents • Dissolved inorganic material: nitrogen, phosphorus and other nutrients from wastes and detergents • Also, pesticides, heavy metals, other toxic compounds © 2011 Pearson Education, Inc. Removing pollutants from wastewater • Technology for treating wastewater must do the job at a reasonable cost • Primary treatment: removes debris and grit • Bar screen: mechanically rakes debris for removal and incineration • Grit chamber: grit is allowed to settle and is removed • Primary clarifiers: tanks where particulate matter settles to the bottom and fatty/oily materials float • Raw sludge: particulates and oily materials that must be treated separately © 2011 Pearson Education, Inc. A diagram of wastewater treatment © 2011 Pearson Education, Inc. Biological nutrient removal (BNR) © 2011 Pearson Education, Inc. Final cleansing and disinfection • Wastewater is disinfected by: • Chlorine gas: effective, cheap, but dangerous to work with • Sodium hypochloride (Chlorox): a safer way to add Cl • Ozone gas: kills microorganisms but must be generated (expensive) • Ultraviolet light © 2011 Pearson Education, Inc. Septic system Sewage treatment for a private home © 2011 Pearson Education, Inc. Eutrophication • • • • Too much phosphorus leaching into lakes, rivers Causes overgrowth of all aquatic plants Plants use all oxygen, animals die Serious type of water pollution © 2011 Pearson Education, Inc. The global phosphorus cycle © 2011 Pearson Education, Inc. Aquatic photosynthesizers © 2011 Pearson Education, Inc. Eutrophication © 2011 Pearson Education, Inc. Eutrophication in shallow lakes and ponds © 2011 Pearson Education, Inc. Combating eutrophication • Applying herbicides: to control phytoplankton but they can also kill fish • Rotting vegetation depletes oxygen, killing more fish • Aerating: plastic tubes with tiny holes dissolve bubbles in the water • Prevent suffocation and breaks down detritus • Harvesting: rooted plants are removed mechanically or by hand—but the roots are left © 2011 Pearson Education, Inc. Public policy and water pollution • The EPA has the responsibility of overseeing U.S. waters • But it can develop regulations only if Congress gives it the authority • The Clean Water Act of 1972 (CWA): gives the EPA jurisdiction over (and requires permits for) all point sources of pollution • $78 billion helps cities and towns build treatment plants • The Clean Water State Revolving Fund (SRF): provides direct grants to build treatment facilities • Money paid back goes as loans to others © 2011 Pearson Education, Inc. Progress has been made • The CWA is one of the most successful environmental laws • 223 million have adequate sewage-treatment plants • Soil erosion has been reduced by 1 billion tons/year • Two-thirds of the nation’s waterways are safe for fishing and swimming • Heavily used rivers, lakes, and bays are restored • Toxic levels in the Great Lakes are reduced • Public policy and billions of dollars have cleaned waters © 2011 Pearson Education, Inc. Rescued baby dugong dies of shock with a stomach full of plastic in Thailand A beloved dugong that went viral in Thailand has died with a stomach full of plastic waste, officials announced Saturday. The 8-month-old animal was being cared for by marine experts after being found last April near a beach in southern Thailand. Officials at the Department of Marine and Coastal Resources believe the female dugong, named Marium, died from a combination of shock and ingesting plastic waste. When Marium was rescued, photos of her cuddling with marine biologists went viral on social media, and she became Thailand's "little angel." Since her rescue, veterinarians and volunteers took canoes to feed Marium and check on her health up to 15 times per day, the Associated Press reported. She was so beloved, the department even set up cameras to live stream her being taken care of and fed. According to the department, Marium was chased last week by a male dugong during the mating season, resulting in bruises. "We assume she wandered off too far from her natural habitat and was chased and eventually attacked by another male dugong, or dugongs, as they feel attracted to her," Jatuporn Buruspat, the department's director-general said Saturday. After the attack, she refused to feed and was moved to a nursery tank Wednesday for close monitoring. She died Saturday morning. An autopsy also found "eight pieces of waste plastic bags packed together" as well as "small plastic fragments" in her intestine, leading to to gastritis and a blood infection. "She must have thought these plastics were edible," Jatuporn said. Dugongs are a species of marine mammal, closely related to manatees. Their conservation status is vulnerable, and the population is decreasing amid threats of pollution and habitat loss. In Thailand, Marium has become a symbol of ocean conservation. The department announced Saturday the Ministry of Public Health will immediately begin implementing a plan to reduce sea waste. Additionally, the "Marium Project" will act as a guideline on how to properly care for and rehabilitate dugongs. "Her death will remind Thais and people all over the world not to dispose trash into the oceans," Natural Resources and Environment Minister Varawut Silpa-arcpha said. © 2019 CBS Interactive Inc. All Rights Reserved. Coca-Cola Just Made the Kind Of Tough Decision That Will Make Some Customers Very Angry February, 1, 2020 Absurdly Driven looks at the world of business with a skeptical eye and a firmly rooted tongue in cheek. The world is ending. It's just that we're not quite sure when and how. It's as well, though, to try and save it for as long as possible using every means possible. Isn't it? I only ask because Coca-Cola made the sort of announcement that might have a few world-caring heads spinning. At the recent Davos Conference of Corporate Champions aka the World Economic Forum, the famous beverage company said that no, no, it wouldn't stop selling its drinks in single-use plastic bottles, so please could you just stop whining. Coca-Cola didn't quite phrase it that way. Instead, its Head of Sustainability Bea Perez said plastic bottles are here to stay because that's what customers actually, really want. As the BBC reported, Perez declaimed: Well, yes, but humans are immensely self-destructive. Shouldn't corporations -- which are people too, after all -- be responsible for helping humans save themselves from themselves? Perez insisted that if the company switched to focus on only glass or aluminum its carbon footprint could increase. Yet Coca-Cola has long been regarded by some as one of the world's greatest plastic polluters. Last year, the pressure group Break Free From Plastic named the company number 1 in its plastic pollution Hall of Shame. Coca-Cola has declared that it will "aspire to create packaging that contains at least 50 percent recycled material by 2030 and continue pursuing the goal to make all consumer packaging 100 percent recyclable by 2025." Aspire to. This clearly won't satisfy some. Even some who are customers. Environmental policy is an emotive subject for many, especially the young. Yet how are corporations supposed to satisfy people's hypocrisy? Everyone cries out for something to be done, yet ululates uncontrollably when that something means individual sacrifice. Should a company do the right thing immediately? Or should it wait for customers to tell it when to do it? You might suspect, however, that Coca-Cola is merely being clever in insisting that consumers don't want to give up plastic bottles. Is it merely trusting its own research? Is it sure this research is accurate? I only ask because a new piece of research has just descended onto my laptop. Performed by research company Piplsay, this study asked 20,832 American consumers what they truly felt about Coke's plastic bottles stance. 26 % of respondents said they quite agreed with Coca-Cola's position. A fulsome 19 % declared: "Whatever, I don't care." Then again, 23 % insisted brands always put profits first. 22 % said the environment was the most important thing and 10 % contented themselves by ticking the box marked: "Really? You're doing this just for us?" That doesn't seem entirely to reflect Coca-Cola's position. Some will wonder, therefore, why the company is so adamant. Coke's Perez believes that people will only move slowly toward the righteous light: But how daring should Coca-Cola be in showing consumers the way? Sometimes, it seems like the biggest companies are the least daring of all. England will ban plastic stirrers, straws and cotton swabs from April 2020 Published Wed, May 22 20198:27 AM EDT Anmar Frangoul A ban on plastic drinks stirrers, straws, and plastic-stemmed cotton swabs will come into force in England next April. “Urgent and decisive action is needed to tackle plastic pollution and protect our environment,” Environment Secretary Michael Gove said in a statement Wednesday. “These items are often used for just a few minutes but take hundreds of years to break down, ending up in our seas and oceans and harming precious marine life,” he added. The ban follows on from a consultation which found that more than 80% of respondents supported a ban on the distribution and sale of plastic straws, with 90% backing a ban on drinks stirrers and 89% in favor of a ban on cotton swabs. The consultation ran from October 22, 2018 to December 3, 2018, and had 1,602 respondents. Outlining details of the ban, the U.K. government said there would be exemptions to make sure that people with a disability or medical requirements could continue using plastic straws. In practice, this means that while restaurants and bars will not be allowed to display plastic straws or “automatically hand them out” they will be able to provide them upon request. Another exemption will apply to the use of plastic-stemmed cotton swabs for “medical and scientific purposes” where such items are “often the only practical option.” The CEO of Surfers Against Sewage, Hugo Tagholm, said the charity welcomed the ban. “Stopping the production and distribution of these single-use plastic menaces will prevent them from polluting beaches nationwide,” he added. “It’s a really positive and bold step in the right direction in the battle against plastic pollution.” Several major businesses are already looking to move away from using plastic in their stores. Fast food giant McDonald’s is rolling out paper straws to stores in the U.K. and Ireland, while upscale supermarket Waitrose now only offers paper straws in its cafes. The issue of plastic pollution is a big problem. Europeans produce 25 million tons of plastic waste per year, according to the European Commission. Less than 30% of this is collected for recycling. 12.12.19 | IMPACT T h e O c e a n C l e a n u p d e v i c e h a s re t u r n e d f ro m t h e P a c i f i c G a r b a g e P a tc h w i t h i t s f i rs t l o a d o f p l a s t i c After months of research, failures, and reconfigurations, and weeks spent at sea traveling to the Great Pacific Garbage Patch and back, The Ocean Cleanup’s device—a 2,000-foot long floating tube that skims the surface of the water to catch plastic trash—has returned to shore. And with it, it brought back 60 bags, sized one cubic meter, full of plastic trash, everything from fishing nets to plastic bags to microplastics one millimeter in size. The end of the first voyage for The Ocean Cleanup, a Dutch nonprofit that hopes to rid the world of ocean plastic, is the end of a long journey for founder and CEO Boyan Slat, who first presented the concept of his device at a TEDx talk in 2012, and has spent the last seven years designing, funding, and deploying it. Now that it’s actually working—pulling debris from the giant vortex of trash that has collected in the Pacific ocean—the next step for the organization is turning that plastic into sustainable products, so you can own a piece of the Garbage Patch and help fund future missions. “To make the clean up happen, it’s not just a technical challenge but also financial, because [with] international waters, there’s not an owner of the Garbage Patch that sees the value in cleaning it,” says Slat. “Basically it’s no one’s problem, but at the same time we believe it’s everyone’s problem What we hope is that by making beautiful, sustainable products out of this catch, we can give an opportunity for everyone to be part of the solution and participate in the cleanup.” The idea is to turn this refuse into consumer products that won’t end up back in the ocean and then invest 100% of those proceeds into more cleanup missions. It’s not yet clear what type of products The Ocean Cleanup hopes to make from its haul, but the nonprofit is already working with partners to create an infrastructure that can clean, sort, and recycle this plastic. They expect to be able to launch the first products in September 2020. If you’re eager to own an item made from ocean plastic, you can guarantee your place in line now with a $50 donation. Consumers have shown more interest in items made from recycled materials lately, and Slat thinks that products made with this ocean plastic could be somewhat of a novelty that garner even more appeal. “It’s not just plastic, it’s plastic with a story, like the difference between a normal rock and a piece of the moon,” he says. “Hopefully, eventually we’re successful, the Garbage Patch is history and will not be there anymore, and then there will still be these cool products that will remind us of it existing back in the day.” That novelty could mean other companies jump on the bandwagon, labeling their products as made from ocean plastic even if they’re not. The Ocean Cleanup says its venture to make products with materials recovered from the Great Pacific Garbage Patch is the first of its kind, and to ensure that these materials are coming from the ocean it’s collaborating with a thirdparty certification specialist, DNV GL, to verify ocean plastic. “There are already products that exist that are being labeled as ocean plastics, but there’s no real transparency in terms of where the plastic is coming from, how much of the plastic is actually coming from the ocean,” Slat says. “We believe it’s important that when people buy something made from plastic from the Garbage Patch, that they know for sure that that is actually the case.” Other companies and foundations can join this effort, as well, to certify that their own plastic is coming from the ocean, if they so choose. The system that returned with the first Garbage Patch-captured plastic has been dubbed System 001/b, and The Ocean Cleanup has already begun preparing for System 002, a new full-scale, fully-operational design. For this first voyage, crew members had to follow the device in a boat and empty the system of its caught plastic every few weeks. Slat hopes to extend that retention ability to months, because fewer trips back and forth with a boat means a more cost-effective cleanup process. “Our goal is to clean up 50% of the Garbage Patch in five years,” Slat says. “For that, we’re going to need a whole fleet of them, and the systems need to be bigger than the ones that we have trialed so far.” You’re literally eating microplastics. How you can cut down exposure to them. A cluster of plastic pieces on a finger. When you eat, drink or even breath, you’re almost certainly taking in tiny particles along with it. These ubiquitous fragments are known as microplastics. (iStock) By Consumer Reports Oct. 7, 2019 For anyone living in the United States in 2019, plastic is nearly impossible to avoid: It lines soup cans, leaches out of storage containers, hides in household dust, and is found inside of toys, electronics, shampoo, cosmetics and countless other products. It’s used to make thousands of single-use items, from grocery bags to forks to candy wrappers. But what many people don’t know is that we’re doing more than just using plastic. We’re ingesting it, too. When you eat a bite of food or even have a sip of water, you’re almost certainly taking in tiny plastic particles along with it. These ubiquitous fragments are known as microplastics. Because research into microplastics is so new, there’s not yet enough data to say exactly how they’re affecting human health, says Jodi Flaws, a professor of comparative biosciences and associate director of the Interdisciplinary Environmental Toxicology Program at the University of Illinois. But “there cannot be no effect,” says Pete Myers, founder and chief scientist of the nonprofit Environmental Health Sciences and an adjunct professor of chemistry at Carnegie Mellon University. It’s likely that ingesting microplastics could further expose us to chemicals found in some plastics that are known to be harmful. These chemicals have been linked to a variety of health problems, including reproductive harm and obesity, plus issues such as organ problems and developmental delays in children. Here’s what you need to know about the tiny bits of plastic in our food and water — and what you can do to try to avoid at least some of them. Why is it in food and water? Humans have produced more than 8 billion tons of plastic, mostly since the 1950s. Less than 10 percent of it has been recycled. Over time, much of it has broken down into tiny particles that make their way into lakes, rivers and oceans, eventually contaminating our food and water. And much of our food comes wrapped in plastic, which leads to tiny particles breaking off into our meals. There is so much plastic all around that we even breathe in tens of thousands of tiny plastic fragments or fibers every year. How much do people ingest? One research review published in June calculated that just by eating, drinking and breathing, Americans ingest at least 74,000 microplastic particles every year. Another recent study commissioned by the World Wildlife Fund and conducted by researchers at the University of Newcastle in Australia estimated that people consume about 5 grams of plastic a week — roughly the equivalent of a credit card. (That work is still under review.) How does it affect health? There is evidence, at least in animals, that microplastics can cross the hardy membrane protecting the brain from many foreign bodies that get into the bloodstream. And there’s some evidence that mothers may be able to pass microplastics through the placenta to a developing fetus, according to research that has not yet been published but was presented at a spring conference at the Rutgers Center for Urban Environmental Sustainability. Myers says some of these microplastic particles could potentially leach bisphenol A and phthalates. Bisphenols are known to interfere with hormones, and there are studies linking bisphenol exposure to reduced fertility in men and women, Flaws says, noting that phthalates are also known to disrupt hormones, and prenatal exposure to phthalates is linked to lower testosterone in male offspring. Styrene, another chemical found in plastic and some food packaging, has also been linked to a number of health issues, including nervous system problems, hearing loss and cancer. Flaws says microplastic particles can also accumulate polychlorinated biphenyls (PCBs), other chemicals that are linked to harmful health effects, including various cancers, a weakened immune system, reproductive problems and more. Once these chemicals are inside of us, even low doses may have an effect. In 2018, the American Academy of Pediatrics (AAP) released a statement recommending that families reduce exposure to these chemicals. “Plastic products were never designed to end up in our oceans,” the Plastics Industry Association (PLASTICS) said in a statement to Consumer Reports. It added that research has not shown “significant human health impacts” from microplastics, but this is something PLASTICS and experts we spoke with agreed requires further study. The American Chemistry Council, another industry group, said in a statement to Consumer Reports that plastics used for food packaging must meet strict Food and Drug Administration safety standards. “To help evaluate the safety of our food, FDA reviews safety information on food packaging materials, including whether tiny amounts of substances could potentially migrate from a package into its contents. Through rigorous analysis, the health experts at the FDA have determined these products to be safe for their intended use.” But not everyone agrees that there’s sufficient oversight. Companies can designate substances that come into contact with food as “generally recognized as safe” (GRAS) without providing peer-reviewed safety evidence to the FDA, a policy Consumer Reports has previously flagged as something that can put consumers at risk. The 2018 AAP report criticized the long list of chemicals that come into contact with food; that report and Myers say these chemicals should be more strictly regulated. 6 tips to curtail your risks You can’t totally avoid microplastics or the chemicals found in plastic. But these small steps can help you avoid at least unnecessary extra exposure: Drink water from your tap. Drinking water is one of the biggest contributors to microplastic ingestion, but bottled water has about double the microplastic level of tap water, according to Sherri Mason, sustainability coordinator at Penn State Behrend and a chemist who has studied plastic in tap water, beer, sea salt, and bottled water. Don’t heat food in plastic. Heated plastics have been known to leach chemicals into food. The American Academy of Pediatrics also recommends not putting plastic into your dishwasher. Avoid plastic food containers with known issues. The AAP report noted that recycling codes “3,” “6,” and “7” respectively indicate the presence of phthalates, styrene and bisphenols. It adds that if these products are labeled as “biobased” or “greenware,” they do not contain bisphenols. Eat more fresh food. Though the levels of microplastics in fresh produce have been largely untested, these products are less likely to expose you to unwanted chemicals, according to the AAP, especially when compared with anything wrapped in plastic. Minimize household dust. Household dust can expose people to chemicals, including phthalates, per- and polyfluoroalkyl substances, and flame retardants, Flaws says. Vacuuming regularly can help reduce household dust exposure, according to the Silent Spring Institute. Think big picture. Individuals can take actions to limit their plastic exposure, Myers says, but large-scale solutions will require reducing the amount of plastic used overall. The experts we spoke with say that consumers should opt for products packaged in glass instead of plastic, use reusable nonplastic containers whenever possible and support policies limiting the use of singleuse plastic. Copyright 2019, Consumer Reports Inc.