3 Earth’s Environmental Systems CHAPTER

The Gulf of Mexico’s Dead Zone Nutrient-rich runoff causes plankton blooms and hypoxia—low oxygen levels—in the Gulf of Mexico. Hypoxia kills or displaces marine organisms, causing a decline in the fisheries and the fishing industry. U.S. government and farmers debate the need to cut down on fertilizer use. Nutrient-rich runoff causes plankton blooms and hypoxia—low oxygen levels—in the Gulf of Mexico. Hypoxia kills or displaces marine organisms, causing a decline in the fisheries and the fishing industry. U.S. government and farmers debate the need to cut down on fertilizer use. Talk About It Do you think the distance between the source of the nitrogen and phosphorus and the dead zones themselves makes it difficult to manage this problem? Why or why not?

Lesson 3.2 Systems in Environmental Science Positive feedback loops can help erosion turn a fertile field to desert in just a few years. Dust storm, Stratford Texas, 1930s

Interacting Systems Lesson 3.2 Systems in Environmental Science Inputs into Earth’s interconnected systems include energy, information, and matter. Feedback loops regulate systems. Negative feedback loops: Result in stabilization of a system Positive feedback loops: Result in a system moving to an extreme Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on. Negative feedback loop

Spheres of Function Earth can be divided into spheres that are defined according to their location and function. Lesson 3.2 Systems in Environmental Science

Lesson 3.3 Earth’s Spheres The movement of Earth’s plates has formed the deepest ocean trenches and the highest mountains.

The Geosphere Crust: Thin, cool, rocky outer “skin” Mantle: Very hot and mostly solid Core: Outer core is molten metal, inner core is solid metal Crust: Thin, cool, rocky outer “skin” Mantle: Very hot and mostly solid Core: Outer core is molten metal, inner core is solid metal Lesson 3.3 Earth’s Spheres Rocks and minerals on and below Earth’s surface: Rock formation, Ouray National Wildlife Refuge, Utah

Plate Tectonics Crust and mantle are divided into: Lithosphere: Crust and uppermost mantle; divided into tectonic plates Asthenosphere: Soft middle mantle; heated by outer core Lower mantle: Solid rock Convection currents in the asthenosphere move tectonic plates. Collisions and separations of the plates result in landforms. Crust and mantle are divided into: Lithosphere: Crust and uppermost mantle; divided into tectonic plates Asthenosphere: Soft middle mantle; heated by outer core Lower mantle: Solid rock Convection currents in the asthenosphere move tectonic plates. Collisions and separations of the plates result in landforms. Lesson 3.3 Earth’s Spheres Volcano lava

Tectonic Plates There are three major types of plate boundary: Divergent Transform Convergent There are three major types of plate boundary: Divergent Transform Convergent Lesson 3.3 Earth’s Spheres

Divergent and Transform Plate Boundaries Divergent boundaries: Rising magma pushes plates apart. Transform boundaries: Plates slip and grind alongside one another. Divergent boundaries: Rising magma pushes plates apart. Transform boundaries: Plates slip and grind alongside one another. Lesson 3.3 Earth’s Spheres Divergent plate boundary Transform plate boundary

Convergent Plate Boundaries Plates collide, causing one of two things to happen: Subduction: One plate slides beneath another. Mountain-building: Both plates are uplifted. Plates collide, causing one of two things to happen: Subduction: One plate slides beneath another. Mountain-building: Both plates are uplifted. Lesson 3.3 Earth’s Spheres

Biosphere: The part of Earth in which living and nonliving things interact Atmosphere: Contains the gases that organisms need, such as oxygen; keeps Earth warm enough to support life Biosphere: The part of Earth in which living and nonliving things interact Atmosphere: Contains the gases that organisms need, such as oxygen; keeps Earth warm enough to support life The Biosphere and Atmosphere Lesson 3.3 Earth’s Spheres Earth’s atmosphere, seen from space

The Hydrosphere Consists of Earth’s water Most of Earth’s water (97.5%) is salt water. Only 0.5% of Earth’s water is unfrozen fresh water usable for drinking or irrigation. Earth’s available fresh water includes surface water and ground water. Consists of Earth’s water Most of Earth’s water (97.5%) is salt water. Only 0.5% of Earth’s water is unfrozen fresh water usable for drinking or irrigation. Earth’s available fresh water includes surface water and ground water. Lesson 3.3 Earth’s Spheres Did You Know? If it is depleted, groundwater can take hundreds or even thousands of years to recharge completely. Greenlaw Brook, Limestone, Maine

Lesson 3.4 Biogeochemical Cycles A carbon atom in your body today may have been part of a blade of grass last year, or a dinosaur bone millions of years ago. Fossilized bones in a Colorado dig.

The Water Cycle Lesson 3.3 Earth’s Spheres

Nutrient Cycling Matter cycles through the environment. Matter can be transformed, but cannot be created or destroyed. Nutrients, matter that organisms require for life process, circulate throughout the environment in biogeochemical cycles. Matter cycles through the environment. Matter can be transformed, but cannot be created or destroyed. Nutrients, matter that organisms require for life process, circulate throughout the environment in biogeochemical cycles. Lesson 3.4 Biogeochemical Cycles Did You Know? Organisms require several dozen nutrients, such as nitrogen, phosphorus, and carbon, to survive.

The Carbon Cycle Lesson 3.4 Biogeochemical Cycles

The Phosphorus Cycle Lesson 3.4 Biogeochemical Cycles

The Nitrogen Cycle Lesson 3.4 Biogeochemical Cycles

Lesson 14.2 Uses of Fresh Water One third of all the people on Earth are affected by water shortages.

Next time you take a drink, think about where that water might have been before.

Next time rain drops fall on you, think about where that water might have been just a few days ago.

Water is a powerful force on Earth’s surface

Water is critical to life…how long can you survive without it?

It is a precious resource we often take for granted

It is sacred to some : The Maya believed natural wells, such as the Xkeken cenote in Mexico's Yucatán, led to the underworld.

Why Does Ice Float?

Why is the ocean cool even when its 100 degrees out?

How Can Water Make It All The Way To The Top Of Trees

Water Is Unique Can’t live without Takes long time to change temperature Stays liquid over large range of temps. Expands when freezes Great at dissolving things Commonly found as solid, liquid and gas Can’t live without Takes long time to change temperature Stays liquid over large range of temps. Expands when freezes Great at dissolving things Commonly found as solid, liquid and gas

According to the U.N., 1 billion people do not have access to clean, reliable fresh water

How Much Water Do You Use Average person in U.S. uses about 80 gallons a day

What can you learn from this chart?

How We Use Water Lesson 14.2 Uses of Fresh Water Three main uses of fresh water include: Agricultural Industrial Personal Did You Know? The average American uses 250 L of fresh water a day for personal uses, such as bathing and brushing teeth.

Using Surface Water Most freshwater used in the U.S. is surface water. Surface water is diverted by canals and dams. Drought and overuse have caused significant surface water depletion. Most freshwater used in the U.S. is surface water. Surface water is diverted by canals and dams. Drought and overuse have caused significant surface water depletion. Did You Know? The Aral Sea was once the fourth largest body of fresh water. Lesson 14.2 Uses of Fresh Water Aral Sea, 1997Aral Sea, 2009

Using Groundwater 68% of groundwater in the U.S. is used for irrigation, most of which is very inefficient. Groundwater mining turns groundwater into a nonrenewable resource because it is withdrawn from the ground faster than it can be replaced. When groundwater is depleted, the falling water tables can cause cities to sink, and undrinkable saltwater to move into the depleted aquifers. 68% of groundwater in the U.S. is used for irrigation, most of which is very inefficient. Groundwater mining turns groundwater into a nonrenewable resource because it is withdrawn from the ground faster than it can be replaced. When groundwater is depleted, the falling water tables can cause cities to sink, and undrinkable saltwater to move into the depleted aquifers. Lesson 14.2 Uses of Fresh Water

Desalination Solutions to Freshwater Depletion Increase supply: Desalination: “Making” fresh water by removing salt from saltwater. Decrease demand: Agricultural: Drip- irrigation, climate- appropriate plants Industrial: Water- conserving processes, recycling wastewater to cool machinery. Personal: Xeriscaping, water conservation Increase supply: Desalination: “Making” fresh water by removing salt from saltwater. Decrease demand: Agricultural: Drip- irrigation, climate- appropriate plants Industrial: Water- conserving processes, recycling wastewater to cool machinery. Personal: Xeriscaping, water conservation Lesson 14.2 Uses of Fresh Water

Lesson 14.3 Water Pollution 3,800 children die every day from diseases associated with unsafe drinking water.

What is Water Pollution? Water Pollution: is the introduction of chemical, physical, or biological substances that affects organisms that depend upon it Many types of water pollution Water Pollution: is the introduction of chemical, physical, or biological substances that affects organisms that depend upon it Many types of water pollution

Types of Water Pollution Point-source pollution: From a discrete location, like a factory or sewer pipe Nonpoint-source pollution: From many places spread over a large area, such as when snowmelt runoff picks up pollutants along its path Point-source pollution: From a discrete location, like a factory or sewer pipe Nonpoint-source pollution: From many places spread over a large area, such as when snowmelt runoff picks up pollutants along its path Lesson 14.3 Water Pollution Point source oil pollution Oil after a spill, Trinity Bay, Texas

Point Sources are usually easily identified

How can a farmer in MT affect a shrimp farmer in Louisiana? NON-Point

A-Nutrient Pollution Excess phosphorous and other nutrients in the water is nutrient pollution. Eutrophication occurs naturally. Nutrient pollution can cause cultural eutrophication. Excess phosphorous and other nutrients in the water is nutrient pollution. Eutrophication occurs naturally. Nutrient pollution can cause cultural eutrophication. THE PROCESS OF EUTROPHICATION Nutrients build up in water. Algae and aquatic plant growth increases. Organisms die. Decomposition requires oxygen. Dissolved oxygen levels decrease. Lesson 14.3 Water Pollution

B- Toxic Chemical Pollution Occurs when harmful chemicals are released into waterways Can be organic or inorganic Harms ecosystems and causes human health problems Occurs when harmful chemicals are released into waterways Can be organic or inorganic Harms ecosystems and causes human health problems Lesson 14.3 Water Pollution

C- Sediment and Thermal Pollution Sediment pollution: Unusually large amounts of sediment that change an aquatic environment Sediment pollution results from erosion. Can degrade water quality, cause photosynthesis rates to decline, and disrupt food webs Thermal pollution: A heat source that raises the temperature of a waterway Heated water holds less oxygen. Sediment pollution: Unusually large amounts of sediment that change an aquatic environment Sediment pollution results from erosion. Can degrade water quality, cause photosynthesis rates to decline, and disrupt food webs Thermal pollution: A heat source that raises the temperature of a waterway Heated water holds less oxygen. Lesson 14.3 Water Pollution

D- Biological Pollution Biological pollution occurs when pathogens enter a waterway. Biological pollution causes more human health problems than any other form of water pollution. Water treatment reduces biological pollution. Biological pollution occurs when pathogens enter a waterway. Biological pollution causes more human health problems than any other form of water pollution. Water treatment reduces biological pollution. Lesson 14.3 Water Pollution Did You Know? Giardiasis is the most common form of waterborne disease in the U.S. Cholera bacteria

E- Groundwater Pollution Sources of groundwater pollution include natural sources, surface pollutants leaching through soil, and leaky underground structures. Chemicals break down more slowly in groundwater than in surface water. Most efforts to reduce groundwater pollution focus on prevention. Sources of groundwater pollution include natural sources, surface pollutants leaching through soil, and leaky underground structures. Chemicals break down more slowly in groundwater than in surface water. Most efforts to reduce groundwater pollution focus on prevention. Lesson 14.3 Water Pollution Did You Know? The EPA repairs and replaces leaky underground gas storage tanks to reduce groundwater pollution. Over the last 25 years, over 1.7 million tanks have been repaired or replaced. Acid drainage from a coal mine

Oil pollution in the ocean comes from many widely spread small sources. Natural seeps are the largest single source. Ocean organisms bioaccumulate mercury pollution. Nutrient pollution can cause red tides. Oil pollution in the ocean comes from many widely spread small sources. Natural seeps are the largest single source. Ocean organisms bioaccumulate mercury pollution. Nutrient pollution can cause red tides. F- Ocean Water Pollution Lesson 14.3 Water Pollution Did You Know? According to the U.S. Oil Pollution Act of 1990, by 2015, all oil tankers in U.S. waters must have double hulls to help prevent against leaks. A 2004 oil spill off the Alaskan coast

Controlling Water Pollution Government regulation decreases water pollution. The Clean Water Act Set water pollution standards Required permits to release point-source pollution Funded sewage treatment plant construction Government regulation decreases water pollution. The Clean Water Act Set water pollution standards Required permits to release point-source pollution Funded sewage treatment plant construction Lesson 14.3 Water Pollution Lake Erie Did You Know? The Great Lakes show that humans can change their ways and clean up trouble spots. In the 1970s, Lake Erie was declared “dead” but is now home to some flourishing species, especially the walleye.

Water Treatment Drinking water is treated to remove pollutants before humans consume it. Wastewater is treated to remove pollutants before human- used water is released back to the environment. Lesson 14.3 Water Pollution Septic systems are the most popular method of wastewater disposal in rural areas of the U.S.