CHAPTER 15 WATER POLLUTION. INTO THE GULF Researchers try to pin down what s choking the Gulf of Mexico

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1 CHAPTER 15 WATER POLLUTION INTO THE GULF Researchers try to pin down what s choking the Gulf of Mexico

2 SAVING THE BAY Teams of researchers try to pin down what s choking the Chesapeake Water pollution harms all of nature and is largely caused by humans. While some types of pollutants are more difficult to address, some can be cleaned, reduced, and ultimately eliminated. Main Concept

3 15 INTO THE GULF Teams of researchers try to pin down what s choking the Gulf TERMS TO KNOW: Water pollution Stormwater runoff Eutrophication Case: Researchers have found that large areas of the Gulf of Mexico turn into oxygen free hypoxic zones and have large amounts of sediment particles and other pollutants.

4 15 TERMS TO KNOW: Water pollution Stormwater runoff Eutrophication When oxygen decreases, things go awry Anything that can degrade the quality of water is considered a pollutant. Uncovered manholes allow chemicals from city streets to enter the storm drains. Water from storm drains, as well as agricultural and suburban runoff, end up flowing into rivers, streams, lakes, and seas. Potential pollutants: Industrial chemicals, raw sewage, garbage, oil, pesticides, mercury, acid, particulates from fossil-fuel combustion, pharmaceuticals, fertilizers, formaldehyde from personal-care products, cleaning solutions

5 15 When oxygen decreases, things go awry Excess nutrients begin the process of eutrophication. For many plants, limiting factors include nitrogen and phosphorus. These are contained in fertilizers that, when washed into a waterway, provide a boost to algae. As the algae flourish, light penetration is reduced and submerged aquatic plants can no longer photosynthesize. Farm fields lose topsoil, fertilizers, and chemicals when heavy rains occur. TERMS TO KNOW: Dissolved oxygen (DO) Hypoxia Biological oxygen demand (BOD) Sediment pollution Estuary

6 15 When oxygen decreases, things go awry Less oxygen is produced as algae take over the role of photosynthesis from the submerged aquatic plants. With less oxygen in the water, other organisms begin to die and decompose. Decomposition uses up more of the limited oxygen, leaving the system hypoxic.

7 When oxygen decreases, things go awry In the Gulf of Mexico, excess nitrogen, phosphorus, and sediment provide part of the explanation for the Gulf s decline. The problems attached to the declining water quality include loss of fisheries compounded by loss of natural filters like seagrasses. Without these natural filters, gills get clogged and spawning areas become covered with sediment. Algae is fortified by fertilizer runoff and grows on the surface of the pond adjacent to a golf course in California. Normally, the algae would not grow in clear lakes of mountain regions.

8 The source of pollution can be hard to pinpoint TERMS TO KNOW: Point source pollution Nonpoint source pollution Watershed Some pollution, such as that coming from wastewater treatment plants, is easy to identify and eliminate. However, some pollution enters the waterway from overland flow. This nonpoint pollution is difficult to source and even more difficult to stop. This structure traps trash flowing down an urban river before it can reach the Baltimore Inner Harbor.

9 The source of pollution can be hard to pinpoint TERMS TO KNOW: Point source pollution Nonpoint source pollution Watershed This structure traps trash flowing down an urban river before it can reach the Baltimore Inner Harbor.

10 The source of pollution can be hard to pinpoint TERMS TO KNOW: Point source pollution Nonpoint source pollution Watershed

11 Excess nutrients flow into groundwater and streams

12 Excess nutrients flow into groundwater and streams TERMS TO KNOW: Aquifer

13 Excess nutrients flow into groundwater and streams

14 Excess nutrients flow into groundwater and streams

15 The number and diversity of organisms can indicate the health of a watershed Excess nitrogen from any rivers and streams within the watershed will eventually flow to a larger body of water. The Gulf of Mexico is one area where excess nutrients have impacted the ecosystem to the point of making a dead zone, or hypoxic area, where most organisms are unable to survive. This satellite image depicts water clarity high sediment loads or algal blooms lack clarity. The red and orange areas are the most turbid (least clear) and at the greatest risk.

16 Identifying the types and sources of the pollution is the first step in cleaning up the bay TERMS TO KNOW: Turbidity Biological assessment Benthic macroinvertebrates Sampling for pollutants and determining their origin are the first steps to recovery. If samples contain high amounts of ammonia (breakdown product of nitrogen), researchers will take more detailed samples from around the site. Analysis of chemistry is a way to examine functioning of the system.

17 Identifying the types and sources of the pollution is the first step in cleaning up the bay Air pollution contributed about the same level of pollutants throughout the test area, but all samples from streams around agricultural sites had the highest levels of nitrogen.

18 Identifying the types and sources of the pollution is the first step in cleaning up the bay Air pollution contributed about the same level of pollutants throughout the test area, but all samples from streams around agricultural sites had the highest levels of nitrogen.

19 Identifying the types and sources of the pollution is the first step in cleaning up the bay Air pollution contributed about the same level of pollutants throughout the test area, but all samples from streams around agricultural sites had the highest levels of nitrogen.

20 Identifying the types and sources of the pollution is the first step in cleaning up the bay Air pollution contributed about the same level of pollutants throughout the test area, but all samples from streams around agricultural sites had the highest levels of nitrogen.

21 Reducing nutrient pollution means reducing it at the source and reducing runoff TERMS TO KNOW: Clean Water Act Pollution standards Best management practices Riparian areas Rain garden It s difficult to believe today, but in 1969 there were no laws regulating what could be discharged into our waterways. The Cuyahoga River in Cleveland, Ohio, was burning because of the amount of oil and chemicals in the water. Passage of the Clean Water Act in 1972 established pollution standards and set in motion establishment of best management practices to reduce pollution entering the bay.

22 Reducing nutrient pollution means reducing it at the source and reducing runoff A major component of restoration involves watershed management managing the areas around the streams and rivers. Farmers manage the use of fertilizers and waste management while encouraging other techniques to reduce excess nutrients and sediments from reaching the bay. Riparian areas need to be restored by planting vegetated buffer zones that slow runoff and give rainwater time to soak into the ground.

23 Reducing nutrient pollution means reducing it at the source and reducing runoff

24 Reducing nutrient pollution means reducing it at the source and reducing runoff

25 Reducing nutrient pollution means reducing it at the source and reducing runoff To reduce nitrogen, pesticide, and sediment runoff, farmers can do a variety of conservation practices.

26 Reducing nutrient pollution means reducing it at the source and reducing runoff To reduce nitrogen additions to water from urban and suburban areas, homeowners can plant indigenous species of grass that require less fertilizer and water. Planting water-tolerant plants in low areas also helps by reducing runoff.

27 Reducing nutrient pollution means reducing it at the source and reducing runoff Changes to residential areas To reduce nitrogen additions to water from urban and suburban areas, homeowners can plant indigenous species of grass that require less fertilizer and water. Planting water-tolerant plants in low areas also helps by reducing runoff.

28 Reducing nutrient pollution means reducing it at the source and reducing runoff Changes to residential areas To reduce nitrogen additions to water from urban and suburban areas, homeowners can plant indigenous species of grass that require less fertilizer and water. Planting water-tolerant plants in low areas also helps by reducing runoff.

29 Reducing nutrient pollution means reducing it at the source and reducing runoff Changes to residential areas To reduce nitrogen additions to water from urban and suburban areas, homeowners can plant indigenous species of grass that require less fertilizer and water. Planting water-tolerant plants in low areas also helps by reducing runoff.

30 Reducing nutrient pollution means reducing it at the source and reducing runoff Changes to residential areas To reduce nitrogen additions to water from urban and suburban areas, homeowners can plant indigenous species of grass that require less fertilizer and water. Planting water-tolerant plants in low areas also helps by reducing runoff.

31 Reducing nutrient pollution means reducing it at the source and reducing runoff Stormwater that doesn t soak into the ground can enter storm drains that flow directly to rivers and streams, or cause floods, especially in heavily built-up urban settings. Anything that increases filtration can help avoid these stormwater problems.

32 Reducing nutrient pollution means reducing it at the source and reducing runoff Stormwater that doesn t soak into the ground can enter storm drains that flow directly to rivers and streams, or cause floods, especially in heavily built-up urban settings. Anything that increases filtration can help avoid these stormwater problems.

33 Reducing nutrient pollution means reducing it at the source and reducing runoff Stormwater that doesn t soak into the ground can enter storm drains that flow directly to rivers and streams, or cause floods, especially in heavily built-up urban settings. Anything that increases filtration can help avoid these Stormwater problems.

34 Reducing nutrient pollution means reducing it at the source and reducing runoff

35 Reducing nutrient pollution means reducing it at the source and reducing runoff

36 Reducing nutrient pollution means reducing it at the source and reducing runoff

37 Reducing nutrient pollution means reducing it at the source and reducing runoff

38 Reducing nutrient pollution means reducing it at the source and reducing runoff

39 Reducing nutrient pollution means reducing it at the source and reducing runoff

40 Reducing nutrient pollution means reducing it at the source and reducing runoff Local authorities need to enforce strict pollution standards and continue urging residents of the bay watershed to maximize their fuel efficiency. Water quality still suffers with heavy rainfall and sea life is still dying off. It is still important to realize that environmental challenges are often very difficult to solve.