8.2 3.1.3 environment  (Page 8/8)

7.3.Why does the level of dissolved oxygen in the river then increase again further downstream?(2)

7.4.Give TWO possible reasons why sewage would be discharged into river systems in a developing urban environment.(4)

7.5.Name one positive and one negative effect that “quite heavy pollution” could have on a rural farming community living at point X downthe river.(2)

Question 8

8.1Humans can influence the environment in ONE of the following positive ways.

ABurning fossil fuels

BConservation

CPollution

DDeforestation

8.2Pollutant gases have an adverse effect on the environment and on our health. The amounts of these gases have been steadily increasing over the years. Thetable below shows the source and amount of some pollutant gases produced by human activities.

8.3.Which ONE of the following statements is correct?

A150 million tons of nitrogen oxide is produced.

BCarbon monoxide is produced by industry.

CSulphur dioxide is produced by vehicle exhaust.

DCarbon monoxide is the gas produced in the largest amount.

8.4.Possible measures for the reduction of air pollution would NOT include

Aproviding subsidies for solar panels

Bproviding subsidies for truck drivers

Crewards for cleaner production by industries

Dimproving the public transport system

8.5Adding harmful substances to the environment is termed

Aexploitation

Bforestation

Cpollution

Ddetoxification

Question 9

The map below shows a region of coastline close to where a giant oil tanker was wrecked at sea. The shallow waters of the coastline provided a rich source ofedible crabs. Oil does not kill the crabs but harm their flesh, making them inedible and they cannot be sold. Samples of crabs were collected at sites A toD. The number of crabs is indicated by the size of the circle. The extent of the shaded part at each site represents the proportion of crabs with diseasedflesh after the disaster.

9.1Which sample site (A to D) had the highest number of crabs? (1)

9.2.In which sample site was the crabs only rarely found?(1)

9.3Name the agent of pollution that affected the crabs.(1)

9.4In which sample site was the most crabs affected compared to the population size? (1)

9.5Explain your answer to QUESTION 2.4(2)

9.6.List TWO strategies that could reduce the effects of oil pollution at sea. (2)

Discussion points

The tragedy of the commons

From: http://cnx.org/content/m16743/latest/?collection=col10548/latest (AP Environmental Science: Environmental Ethics) from Connexions

In his essay, The Tragedy of the Commons, Garrett Hardin (1968) looked at what happens when humans do not limit their actions by including the land as part oftheir ethic. The tragedy of the commons develops in the following way: Picture a pasture open to all. It is to be expected that each herdsman will try to keepas many cattle as possible on the commons. Such an arrangement may work satisfactorily for centuries, because tribal wars, poaching and disease keepthe numbers of both man and beast well below the carrying capacity of the land. Finally, however, comes the day of reckoning (i.e., the day when the long-desired goal of social stability becomes a reality). At this point, the inherent logic of the commons remorselessly generates tragedy.

As a rational being, each herdsman seeks to maximize his gain. Explicitly or implicitly, more or less consciously, he asks: "What is the utility to me ofadding one more animal to my herd?" This utility has both negative and positive components. The positive component is a function of the increment of oneanimal. Since the herdsman receives all the proceeds from the sale of the additional animal, the positive utility is nearly +1. The negative component isa function of the additional overgrazing created by one more animal. However, as the effects of overgrazing are shared by all of the herdsmen, the negativeutility for any particular decision-making herdsman is only a fraction of -1.

The sum of the utilities leads the rational herdsman to conclude that the only sensible course for him to pursue is to add another animal to his herd, andthen another, and so forth. However, this same conclusion is reached by each and every rational herdsman sharing the commons. Therein lies the tragedy: eachman is locked into a system that compels him to increase his herd, without limit, in a world that is limited. Ruin is the destination toward which all menrush, each pursuing his own best interest in a society that believes in the freedom of the commons. Freedom in the commons brings ruin to all.

Hardin went on to apply the situation to modern commons. The public must deal with the overgrazing of public lands, the overuse of public forests and parksand the depletion of fish populations in the ocean. Individuals and companies are restricted from using a river as a common dumping ground for sewage andfrom fouling the air with pollution. Hardin also strongly recommended restraining population growth.

The "Tragedy of the Commons" is applicable to the environmental problem of global warming. The atmosphere is certainly a commons into which many countriesare dumping excess carbon dioxide from the burning of fossil fuels. Although we know that the generation of greenhouse gases will have damaging effects uponthe entire globe, we continue to burn fossil fuels. As a country, the immediate benefit from the continued use of fossil fuels is seen as a positive component.All countries, however, will share the negative long-term effects.

Additional resources

Plants can tell us about climate change

See how the general public are helping scientists monitor climate change by observing the timing of leafing, flowering, and fruiting of plants (plantphenophases).

Project Budburst http://neoninc.org/budburst/

Ecology site

http://www.ecology.com

The Story of Stuff

To see how humans can affect the environment: watch “The story of stuff”: http://youtu.be/9GorqroigqM

Answers

Question 1

1.1B

1.2D

1.3B

1.4.C

Question 2

2.1.Sample site A

2.2.Sample site D

2.3.Oil

2.4.Sample B

2.5.Sample B has greater shaded portion

2.6.Regular service of oil tankers

Legislation on the amount of oil the oil tankers transport

Monitoring of travel routes

Use bacteria to dissolve the oil spill

EXCELLENT RESOURCES, QUESTIONS, ACTIVITIES IN MINDSET LEARN MATERIAL!!!!!