1. Human- Environment Interaction Unit 3

2. Desertification  A type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as climate change and human activities. Desertification is a significant global ecological and environmental problem. (Wikipedia)

3. Desertification Continued Causes of desertification include:  Removal of vegetation cover  Overgrazing  Uncontrolled fuel wood collection  Unsustainable farming practice and loss in fertility of soil  Excessive tree felling

5. Deforestation  Deforestation is clearing Earth's forests on a massive scale, often resulting in damage to the quality of the land. Forests still cover about 30 percent of the world’s land area, but swaths the size of Panama are lost each and every year.

6. Deforestation Causes  According to the United Nations Framework Convention on Climate Change (UNFCCC), the overwhelming direct cause of deforestation is agriculture. Subsistence farming is responsible for 48% of deforestation; commercial agriculture is responsible for 32% of deforestation; logging is responsible for 14% of deforestation and fuel wood removals make up 5% of deforestation

7. Deforestation

8. Cost-Benefit Analysis  A process of examining the advantages (benefits) and disadvantages (costs) of each available alternative in arriving at a decision.  To determine the economic, social, environmental, and cultural impact of a project.

9. Alternate Energy  An any energy source that is an alternative to fossil fuel.  Renewable energy vs. Non-renewable energy  Alternative energy sources are renewable and are thought to be "free" energy sources. They all have lower carbon emissions, compared to conventional energy sources.

10. Background  Everyday, the world produces carbon dioxide that is released to the earth’s atmosphere and which will still be there in one hundred years time. This increased content of Carbon Dioxide increases the warmth of our planet and is the main cause of the so called “Global Warming Effect”. One answer to global warming is to replace and retrofit current technologies with alternatives that have comparable or better performance, but do not emit carbon dioxide. We call this Alternate energy.

11. Common Types of Alternate Energy  Solar energy is the generation of electricity from the sun. It is split up into two types, thermal and electric energy. These two subgroups mean that they heat up homes and generate electricity respectively.  Wind energy is the generation of electricity from the wind.  Geothermal energy is using hot water or steam from the Earth’s interior for heating buildings or electricity generation.  Biofuel and ethanol are plant-derived substitutes of gasoline for powering vehicles.  Nuclear binding energy uses nuclear fission to create energy.  Hydrogen is used as clean fuel for spaceships, and some cars.

12. Solar

13. Wind

14. Geothermal

15. Biofuel

16. Sustainability  Sustainability is based on a simple principle: Everything that we need for our survival and well-being depends, either directly or indirectly, on our natural environment. Sustainability creates and maintains the conditions under which humans and nature can exist in productive harmony, that permit fulfilling the social, economic and other requirements of present and future generations.

17. Sustainability There are two major ways of reducing negative human impact and enhancing ecosystem services. 1. Environmental management. This approach is based largely on information gained from earth science, environmental science and conservation biology. The second approach is 2. Management of human consumption of resources, which is based largely on information gained from economics.

18. Sustainability  Sustainability is important to making sure that we have and will continue to have, the water, materials, and resources to protect human health and our environment.

20. Opportunity Cost  The cost of an alternative that must be forgone in order to pursue a certain action. Put another way, the benefits you could have received by taking an alternative action.

21. Example  If a gardener decides to grow carrots, his or her opportunity cost is the alternative crop that might have been grown instead (potatoes, tomatoes, pumpkins, etc.).In both cases, a choice between two options must be made. It would be an easy decision if you knew the end outcome; however, the risk that you could achieve greater "benefits" (be they monetary or otherwise) with another option is the opportunity cost.

22. Example