Human Impact on the Environment:

Current Crises for Human Survival:Problems to be Solved Within the Next Generation

Practical observation of ONE example of human influence on the environment in the local area (e.g. the impact of alien species on biodiversity). Written report on the chosen example.Look at the interrelatedness and interdependence of the human impacts and the environment.

In nature all things are recycled

Humans upset the cycles

What have you noticed?

Food costs

Transport

Energy Costs

Fish

Weather

More buildings

Research: Human impact on the environment

Discuss what you

understand these terms

to mean

The atmosphere and climate change

• carbon dioxide emissions;• - concept of ‘carbon footprint’ and the need

to reduce the carbon footprint;• - deforestation;• - greenhouse effect and global warming:

– desertification, drought and floods;• - methane emissions;• - ozone depletion.

http://www.vanderbilt.edu/sustainvu/2009/03/so-what-is-a-carbon-footprint-and-why-is-vanderbilt-calculating-one/

Carbon footprint: the amount of carbon dioxide or other carbon compounds emitted into the atmosphere by the activities of an individual, company, country.

Brainstorm what you can do to

reduce your carbon footprint

http://www.epa.gov/climatechange/kids/basics/index.html

• Desertification is a complex process involving multiple natural and human-related causes. In desertification, the productive potential of arid and semi-arid lands falls by 10% or more, and topsoil is lost or degraded.

– Desertification results mainly from a combination of natural climate changes causing prolonged drought and unsustainable human activities, including overgrazing and deforestation.

– Desertification may lead to the formation of a desert or the encroachment of an existing desert onto formerly arable land.

Overgrazing on marginal lands (top) can

extend desert zones (lower)

Effects of Climate Change

Effects of Climate Change

Effects of Climate Change

http://www.epa.gov/climatechange/kids/

Research what individuals, schools,

communities and businesses can do to

reduce climate change

Most household cleaning can be done with a half-and-half mixture of vinegar and water, or liquid soapand baking soda.

Most household cleaning can be done with a half-and-half mixture of vinegar and water, or liquid soapand baking soda.

If it has a thermostat it uses a large amount of electricity.

How can your family/school

reduce its electricity

consumption?

Not all SA’s have access to safe water.

Investigate how human activity affects

water quality and availability and

suggest solutions

Water:Availability:

• Construction of dams• - Destruction of wetlands• - Poor farming practices• - Droughts and floods• - Exotic plantations and depletion of water table• - Boreholes and effects on aquifers• - Wastage• - Cost of water

Water: Quality

• - Water for domestic use, industry, agriculture and mining: pollution, diseases, eutrophication and algal bloom.

• - The effect of mining on quality of water• - Thermal pollution The need for water

purification and recycling• - Alien plants, e.g., Eichornia

Monoculture

Dams

Floods and Droughts

Boreholes and effects on ground water

Exotic plantations

Invasive alien plants eg

Water hyacinth/Eichonia

http://wetlands.sanbi.org/

• Wetlands are areas where terrestrial and aquatic ecosystems come together.

• In a wetland, the water table is at or near the surface of the ground. The land is either temporarily or permanently covered with shallow water.

What is a wetland?

http://www.unwater.org/worldwaterday/hungry_thirsty.html

Food security is built on three pillars:•Food availability: sufficient quantities of food available on a consistent basis.•Food access: having sufficient resources to obtain appropriate foods for a nutritious diet.•Food use: appropriate use based on knowledge of basic nutrition and care, as well as adequate water and sanitation.

http://www.who.int/trade/glossary/story028/en/

Think of food wastage at home/

school/ shops – how can this be

reduced and contribute towards food security for all

Food Security (link with population ecology dynamics)

• human exponential population growth;• - droughts and floods (climate change);• - poor farming practices: monoculture; pest

control,• loss of topsoil and the need for fertilisers;• - alien plants and reduction of agricultural land;• - the loss of wild varieties: impact on gene pools;• - genetically engineered foods;• - wastage.

Biodiversity is the degree of variation of life forms within a given species, ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate

http://www.novamind.com/connect/nm_documents/285

http://www.novamind.com/connect/nm_documents/285

http://www.eco-question.com/what-are-the-main-causes-of-biodiversity-loss

Loss of Biodiversity (the 6th extinction)

- habitat destruction: farming methods, e.g.,•overgrazing and monoculture, golf estates, mining,•urbanisation, deforestation; loss of wetlands and•grasslands;- poaching, e.g., for rhino horn, ivory and ‘bush meat’;- alien plant invasions: control using mechanical, chemical and biological methods; and- indigenous knowledge systems and the sustainable use of the environment e.g., devils’claw, rooibos, fynbos, the African potato (Hypoxis) and Hoodia.

Loss of Biodiversity (the 6th extinction)

Investigate: Rhino poaching in South Africa: read articles and make suggestions on how it can be prevented.

Solid Waste Disposal

• - managing dumpsites for rehabilitation and• prevention of soil and water pollution;• - the need for recycling;• - using methane from dumpsites for domestic

use:• heating and lighting; and• - safe disposal of nuclear waste.

Solid Waste Disposal

• Analyse the solid waste generated in the household in one week, including paper, metals and plastic.

• Estimate the percentage that could be recycled or reused.

• Visit a municipal landfill site, or a local refuse dump. Observe rehabilitation (or lack thereof) in practice.

• Assess the effectiveness of waste management.

If anything in your dustbin can be reused by somebody else, recycled or repaired it should notbe there!

Waste is Costly• The earth is a closed system. • Any nutrients and resources being

taken out of the system (and buried in a landfill, or burnt) are resources lost to us.

To produce one ton of paper, 100 tons of water are used.For every litre of beer, 10 litres of water have been used in the fermenting process.Producing one cellphone requires 75 kg of resources.A toothbrush requires 1,5 kg of resources – coal, oil and water – for its production

Types of waste

Methane gas from landfill sites to energy

Benefits of recycling• reduces the amount of waste going into

landfill sites, saving airspace;• creates jobs and money for schools and

organisations;• reduces pollution and litter;• saves raw materials needed to make new

products;• reduces the need to import expensive

raw materials;

Benefits of recycling• slows down the use of the world’s non-

renewable (oil, coal and iron) and renewable resources (trees);

• reduces energy costs in manufacturing of containers, packaging, etc.

• saves water (used in packaging and product manufacture). Recycling paper uses 50% less water than paper that is made from wood pulp.