Chapter 15: Human Populations Population Dynamics Chapter 15: Human Populations

1. ) Write a short description of this graph 1.) Write a short description of this graph. Predict why it looks like this. 2.) sketch the graph and predict what will happen next 3.) Discuss with the people around your prediction.

Factors that led to human growth? Limiting factors that will result in Earth’s carrying capacity?

As the human population increases …… Overexploitation of resources Environmental degradation Pollution Climate change Soil fertility

Human Demographics-cont’d Thomas Malthus predicted that exponential population growth would surpass arithmetic food production growth

Food production already estimated to be at a maximum. Land loss, livestock degradation, fertility decline, climate change, overexploitation of wild resources Solutions? Brain storm with the people around you of some possible solutions and then share with the class.

Food and Soil Genetically Modified Organisms (GMOs) Pros Cons Crops can be engineered to resist pests, to resist extreme temperatures, to have improved nutritional content , to have improved flavour, to produce bigger yields Cons Potential loss of genetic diversity Farmers need to purchase seeds regularly which will be difficult for poor farmers May end up in products unintentionally May not be indicated on food labels

Water & Air Fresh water being consumed Water being polluted Acid rain Air pollution Greenhouse effect Solutions? Again brainstorm with the people around you and share your ideas with the class.

Ecological Footprint: Estimate of the amount of land and water needed to supply resources and deal with wastes produced by a human population In a group of 2 or 3 complete Activity 15.5.1

Restoration Ecology and Waste Management Five Rs of waste reduction: Reduce Reuse Recycle Refuse Recover Biologists continuously monitor components of carrying capacity (ex. soil, water, air) to assess changes in ecosystems. To do this, they: Establish baseline data Measure and observe indicators (ex. water turbidity) Examine indicator species (ex. frogs)

Bioremediation: Organisms (ex. bacteria) are used to detoxify polluted environments (ex. oil spills) They use enzymes to break down toxic chemicals to less toxic/nontoxic chemicals they can digest Eventually the organisms die from starvation

Restoration Ecology and Waste Management-cont’d Two ways of dealing with global pollution: Prevent, reduce, eliminate pollutant production (ex. wind and solar power) Continue cleaning up pollutants after they have been produced Eco-cities: Cities designed to minimize their impact on the environment and to establish sustainable lifestyles

Restoration Ecology and Waste Management-cont’d High-Throughput Economy: Sustains economic growth by increasing resource movement These resources are eventually output as wastes and pollution Low-Throughput Economy: Efficient use of energy resources Reuse and recycle most non-renewable resources Allow renewable resources time to regenerate Decrease unnecessary consumption Pollution prevention focus (ex. reduce wastes)

Activity 15.4.1