Environment 7: Grade 11

Grade 11: Eco Curriculum


B. The significance of water masses (Context: Africa and the World)
■ Forms of exploitation and its impact on sustainable living (e.g. commercial and subsistence fishing, mining, dumping of waste).
■ Hazards and environmental management of hydrological systems (e.g. rivers, coastal resource management).

C. Ecosystems (biotic and abiotic components) (Context: Africa and the World)
■ Concepts (e.g. biosphere, ecosystem, biome, food webs and chains).
■ Ecological processes (e.g. energy flow, nutrient cycling, self-regulation).
■ Soil processes, soil profile and soil forming factors.
■ Human impact on ecosystems and the consequences.
■ Vegetation regions in Africa:
• distribution;
• comparing different biomes;
• human impact on different biomes.
■ Environmental relationships (influence of climate, soil, topography, veld fires on biomes).

D. Development and sustainability (Context: Africa and the World)
■ Concepts of ‘development’ and ‘sustainability’ at global and national scales.
■ Indicators of development (social or economic) and sustainability.
■ Models and theories of development over time.
■ Rural and urban development: successes and failures.
■ The unevenness of development globally (North/South divide).
■ Contrasting developed and developing countries in terms of indicators.
■ Changing patterns of agriculture, industry, transport, trade and settlement.
■ Strategies by people, organisations and nations to address development problems.
■ Application of development strategies in local context.

E. People and their needs (Context: Africa)
■ Resource use and management:
• resources and their uses;
• distribution and utilisation of renewable and non-renewable natural resources;
• concepts of ‘resources
• extraction of raw materials, the conflicts and opportunities that are created;
• land use conflicts in national parks;
• the impact of values and attitudes of people affected.
■ Energy use and management:
• increasing demand for energy;
• relative and changing importance of fossil fuels, nuclear power and alternative energy sources;
• the environmental costs of energy provision;
• causes and effects of energy production related to pollution;
• causes and consequences of acid rain and the importance of international co-operation;
• environmental effects of resource and energy consumption on world temperatures;
• sustainable energy principles and approaches – consider new forms of energy and approaches to energy conservation.
Positive and negative feedback
Differentiate between positive and negative feedback
Explain the mechanism of negative feedback that exists between the hypophysis/pituitary and the thyroid gland (TSH and thyroxin)
Explain the mechanism of positive feedback between the adrenal gland and the pancreatic islets (adrenalin and glucagon)

Human influences on environment

Food pyramids
Define a food pyramid
Distinguish between pyramids of numbers, biomass and energy
Construct food pyramids involving humans as one of the consumers

Effect of environmental changes on food pyramids
 Analyse data on the changes in human population size over a period of time
 Using examples of food pyramids, describe the effects of human overpopulation on them
 List THREE examples of situations where humans may use pesticides
 Using examples of food chains, describe the effects of pesticides on food pyramids
 Discuss advantages and disadvantages of using pesticides
 Explain what is meant by culling
 List at least THREE reasons why animals are culled
 Using examples, describe the impact of culling on food pyramids
 Research attitudes of  people towards culling
 Describe the effects on food pyramids of at least ONE example of each of the following types of pollution
o Air pollution
o Land pollution
o Water pollution
 State what is meant by deforestation
 Explain why deforestation occurs
 Describe the effects of deforestation on food production and consumers


Sustaining / Management our Environment

Management of cause and effects of pollution
Review the causes and effects of examples of air, water and land pollution

For each type of pollution:
 Explain ways in which that type of pollution can be prevented/controlled
 Explain how the effects of each type of pollution can be reduced / eliminated

Research any one example of pollution in your school or local community to identify the causes of this pollution and list ways in which the incidence of pollution and its effects can be reduced.

Discuss legislation relating to pollution

Management of cause and effects of deforestation
Review factors that may lead to deforestation

Describe the effects of deforestation such as the impact on:
 Habitat of organisms
 Soil erosion
 Carbon cycle
 Water cycle

Explain ways in which deforestation can be reduced such as through:
 Re-use of wood products eg. paper
 Re-cycling wood products
 Using alternate sources for fuel other than wood

Explain ways in which the effects of deforestation can be managed such as through
 Harvesting forest products in a more sustainable way
 Replanting to replace the trees that have been removed/destroyed
 Encouraging tree planting in schools and in local communities

Discuss issues around the need to balance the need for deforestation with the need to remove these forests to satisfy human needs eg. agriculture, houses etc.

Management of the use of land
List some of the main ways in which land is used such as for:
 agriculture
 grazing
 housing
 industries
 mining
Discuss problems related to each of the above-mentioned land uses and possible solutions to the problems.
Discuss the influence of past and present politics on the availability and use of land
Eg.: Overgrazing results in erosion. To prevent this, the number of animals should be allocated to a grazing area according to the carrying capacity of that area.

Draw a pie chart to represent the usage of your school property for each of the following purposes:
 School buildings
 Parking
 Cultivated gardens
 Natural vegetation
 Sports fields/Playgrounds

Use the information from the pie chart to explain ways in which land use of the school property could be improved from an environmental point of view.

Management of the cause and effects of extinction
List factors that may lead to the extinction of plant and animal species

Describe the impact of the extinction of plant and animals species such as:
 Disrupting food chains through loss of biodiversity
 Loss of medicinal products derived from these plants and animals
 Loss of the valuable effect of the presence of plants and animals eg. loss of a particular species that is required as an agent of pollination or dispersal (insects, birds), or of a species that is an important participant in succession (eg. mosses and ferns) or in increasing soil fertility (leguminous plants that have nitrogen-fixing bacteria).

Explain ways in which extinction of species can be prevented

Conduct research on any one extinct animal with regard to:
 Where and when the organism existed
 What the organism ate
 The ecological role of the organism
 Circumstances that led to its extinction

Describe any ONE current human activity that may contribute to the extinction of species, such as habitat destruction, over-exploitation for purposes of food, medicine etc., excessive use of pesticides etc.
Population studies

Define a population as a group of organisms of the same species which live in the same habitat so that random interbreeding takes place
Define a species as a group of organisms which share the same characteristics and are capable of interbreeding
Define a community as a group of populations living together in the same habitat.

Characteristics of populations
Outline characteristics of populations in terms of:

 Habitat
o Outline the large variety of habitat types that are occupied by populations
o Explain why particular populations can exist in certain habitat types only
o Briefly explain the impact of habitat destruction on the survival of populations

 Size and Density
o Differentiate between population size and population density
o Explain the importance of determining population size such as in:
 determining the extinction status of organisms
 planning for the utilization of resources
 making decisions on culling
 setting limits for fishing
 making decisions increasing the stock of grazing animals on a farm (based on carrying capacity)

o List various factors that may influence the size of a population

 Distribution
o State that populations are found in habitats that may be distributed in different parts of the world
o State that the distribution of populations is mainly influenced by climate
o Use one example of a plant and an animal population to show their distribution in different parts of the world

Population growth and Determination of population size
State that a population growth pattern/form refers to the pattern of change in the size of a population over a period of time
Explain what is meant by environmental resistance and carrying capacity
Using graphs, outline the characteristics of the following growth patterns/forms
 Geometric growth form(j-shaped curve)
 Logistic growth form (s-shaped curve)

Describe the pattern of human population growth from 1650 to the present to highlight the following:
 The rapid increase in the population size
 The time taken for each doubling of the population
 Making predictions about future growth of the human population

Analyse given data and findings to evaluate growth of human populations eg. comparison of population growth in first- and third world countries.

Describe the following methods that could be used to determine population size:
 Direct technique (census)
 Indirect technique  – simple sampling
– mark recapture

Conduct practical work, using any indirect technique, to determine the size of a population

Population fluctuation
Using examples, describe the influence of TWO or more external factors (factors related to the environment) on population size such as:
 Earthquakes
 Volcanoes
 Earth slide
 Tornadoes
 Droughts
 Floods
 Extreme temperatures

Using examples, explain the influence of each of the following internal factors (factors directly related to the population) on population size:
 Natality – definition, influence on population size, fertility and fecundity rate
 Mortality – definition, influence on population size
 Dispersal (immigration, emigration and migration) – definition, influence on population size
 Competition
 Disease
 Predation

Analyse given data and findings to evaluate the impact of particular internal and external factors on population size
Analyse and evaluate any specific human behaviour (e.g. deforestation/culling/habitat destruction/pollution)  that will influence population size
Social behaviour

Explain what is meant by each of the following concepts as it relates to the survival of populations
 Preservation
 Conservation
 Sustainability

Differentiate between instinctive and socially learnt behaviour as it relates to the survival of populations

Examples of social behaviours
Explain how each of the following social behaviours contributes to the survival of populations:
 Predation
 Competition
 Courtship/Mating behaviour
 Altruism
 Territoriality
 Interaction of successive broods
 Analyse given data and findings to evaluate the impact of particular social behaviours on the survival of populations

Managing populations

Significance and value of biodiversity
Discuss the significance and value of biodiversity to ecosystem function and human survival for each of the following:
• food
• materials for clothing and shelter
• energy for transport and everyday use
• medicines

Threats to biodiversity
Describe how any THREE of the following poses a threat to biodiversity:
• Deforestation
• Diseases
• Agricultural practices
• Natural disasters
• Pollution
• Desertification
• Alien invasive plants
• Over-exploitation of resources

Name at least TWO plants and TWO animals that have become extinct over the past years
Name at least TWO plants and TWO animals that are considered as endangered species  in the red data list
Discuss the impact of the over-use of  plants and animals for muti and traditional purposes as well as for Western medicine and suggest strategies that could be used to manage this practice

Biodiversity of plants and animals and their conservation
Conduct research on ONE example of a successful conservation strategy to address the following:
• State which plant or animal resource was conserved
• Explain why there was a need for conservation
• List reasons for the success of the conservation strategy
• Describe some challenges experienced, if any
• Explain the impact of the selected strategy on biodiversity

Discuss legislation pertaining to ONE example of conservation and sustainable use of indigenous fauna and flora such as:
• Permits for fishing
• banning the catching of undersized fish
• limiting numbers of fish caught
• permits for cycads
hunting regulations
Management of diseases
Discuss the management of any ONE disease such as
• foot and mouth disease
• TB in lions and buffalo
• bird flu

Explain how each of the following plays a role in the management of disease:
• Quarantine
• Inoculations
• Information dissemination
• Legislation in preventing the spread of diseases nationally and globally
• Collect and analyse data on ONE disease and explain how it can impact on the population and the community.