Exam 20: Water Pollution and Its Prevention

Which of the following farming practices were recommended to mitigate the dead zone in the Gulf of Mexico just west of the Mississippi River?

Homeowners living in a heavily forested region surrounding a small 3-acre pond in Missouri decided to reduce air pollution in their neighborhood.In the fall,after the oak and maple leaves had fallen,the homeowners blew all of the dead leaves into the pond.About 8 months later,in July,they noticed a large number of dead fish in the pond.What is the most likely cause of the fish kill?

Which one of the following is not used to disinfect treated wastewater ready to be released into natural waterways?

Noticing large amounts of algal growth in her small farm pond,a farmer adds about 20 grass carp to feed on the abundant algae and plants.After several years,the carp grow large,exceeding 20 pounds each in size.Late one summer,the farmer notices that the carp and most of the other fish are dead.The water also smells very bad.Which one of the following is the most likely explanation for the death of these fish?

In downtown Philadelphia,water in storm drains most likely came from

A small neighborhood pond averaging about 3 meters in depth reveals all the signs of cultural eutrophication,most likely from runoff of lawn fertilizers used by the residents.The water is very cloudy and oxygen levels remain very low,resulting in few fish that can survive.To provide some opportunities for the neighborhood kids to regularly catch fish,the neighborhood association decides to purchase,install,and run a large water fountain in the middle of the pond. -Instead of addressing the symptoms of cultural eutrophication,the neighborhood association could address the cause of the problem by

-The people using this river increase their health risks the most if they use the same area of the river for drinking and

One of the most common sources of phosphate pollution that has led to eutrophication has resulted from the use of

Which of the following regions still struggles with severe cultural eutrophication?

The best way to reduce the pollution of agricultural fertilizer runoff from farm fields is to

Which of the following should not be flushed down the drain in a home with a septic tank?

Based upon the history of the U.S.federal government's involvement in controlling water pollution,which one of the following scenarios would have most likely occurred?

The trickling-filter system and the activated-sludge system both require

In a small pond,which averages about 6 feet deep or less,eutrophication typically produces

Duckweed is a small,flowering plant that floats at the water's surface.It tends to grow best when nutrient levels are high.When duckweed is abundant,it forms tight mats that cover the surface of ponds and lakes.Consider a situation in which spring storms bring an influx of water and nutrients into a small 4-acre pond,and duckweed populations suddenly explode.Duckweed covers nearly all the surface of the pond,but is regularly washed over the spillway only to be replaced rapidly by the growth of new duckweed plants. -While the duckweed continues to cover the water's surface of this pond undergoing eutrophication,it is most likely that the water clarity will

Devastating earthquakes struck Haiti in January 2010,forcing the native people to live under the most primitive of conditions.Which one of the following forms of immediate aid would most likely prevent the outbreak of cholera and dysentery in refugees who were not seriously harmed by the earthquakes?

In the regions of the dead zone in the Gulf of Mexico just west of the Mississippi River delta,oxygen levels are

Which of the following is one of the most common factors contributing to cultural eutrophication of lakes near large cities?

Harmful algal blooms appear to be linked to unusually high levels of nutrient pollution.Which of the following is the most likely source of nutrient pollution in a river drainage system associated with an algal bloom?

Anaerobic conditions will most likely be generated in a natural water system with