Earth Sustainability

1. Earth Sustainability

2. Sustainability:sustainable: rate at which a renewable resource can be used without reducing its available supply “meet the needs of the present without compromising the ability of future generations to meet their own needs.”

3. Sustainability involves: The Environment • Economics • Sociology • Politics

4. Why Sustainability is Global: The Environment is Global: If a country tried to act sustainably… …would Global Warming cease for that country?

5. Sections • 1. Alternate Energy in North Carolina • 2. Population Dynamics • 3. Agriculture/Aquaculture • 4. Ecological Footprint

6. Alternate Energy in North Carolina

7. Alternate Energy • NC is one of just a few states in the US that has a legislative renewable energy mandate.  • NC utilities must have a percentage of their retail sales come from renewable energy sources. • Up to 12.5% by 2021. 

8. Solar Energy • Solar Energy uses photovoltaic (PV) panels to convert sunlight into electricity • North Carolina Solar House at NC State • House is run entirely off of solar energy

10. Solar Energy • Advantages • Produces no pollution • Provides free energy • Very quiet • Disadvantages: • Initial cost of solar panels is expensive • Weather can affect effectiveness of solar panels • Only work during daylight hours.

11. Nuclear Energy • In nuclear fission, the nuclei of heavy atoms such as uranium-235 are bombarded with neutrons • The uranium nuclei split into smaller nuclei and emit neutrons and heat energy • North Carolina State Nuclear Plant

12. North Carolina State University Nuclear Plant

13. Nuclear Energy • Advantages: • Create very small amounts of pollution • Very reliable • High levels of electric energy can be created at one nuclear energy plant • Disadvantages: • Radioactive waste (must be monitored for 10,000 years after it is used • Meltdown, Chernobyl • Threat of nuclear terrorism

14. Wind Energy • In the next 50 to 60 years, wind power could be used to create between 5 to 10 percent of the country’s demand for electricity. • Wind energy is generally used in coastal areas of North Carolina

15. Modern Vertical Wind Turbine

16. Wind in North Carolina

17. Wind Energy • Advantages • Self-sustaining • Reliable • Causes little to no harm to plant and animal life on the ground • Disadvantages: • Not 100% reliable (wind speeds must be at least 16 mph) • High initial cost

18. Hydroelectric Power • Hydroelectric power is the power generated by falling water. • The water held in a reservoir behind a dam that can be released through the dam to produce electric power. • The strong water flow that results drives turbines and electric generators

19. Cowans Ford Dam • Cowans Ford Hydro Station is located in Huntersville, N.C., on Lake Norman. • It is the largest conventional hydro station owned by Duke Energy.

20. Hydroelectric Power • Advantages: • No fossil fuels • Controls flooding • Very few breakdowns • Disadvantages: • Disrupts natural ecosystems • Expensive to build

21. Geothermal Energy • Geothermal Energy takes heat from Earth’s interior • Heat within the Earth raises the temperature of groundwater • Water is converted to steam • Can only be done near plate boundaries • Not in North Carolina

24. Energy Efficiency • Energy efficiency is the use of energy resources in ways that are more productive • How can energy efficiency be improved? • Recycling • Installing solar panels • Not using fossil fuels

25. Population Dynamics

26. Population Growth • All organisms are members of populations • Populations die and grow at steady rate based on the amount of resources available • Change in response to environmental stress

27. Exponential Growth • Populations experience exponential growth • Initial increase in organisms is slow (small number of reproducing organisms) • Population then sharply increases due to high amount of reproduction • Growth curve shaped like a “J”

28. Exponential Growth • In exponential growth a populations rate of production grows or stops in response to limiting factors • Limitations: • Availability of food • Disease • Predators • Lack of space

29. Carrying Capacity • A populations carrying capacity is the number of organisms than an environment can support • Births exceed deaths until resources run out

30. Population Crash: occurs when a population overshoots carrying capacity and environmental pressures cause effects. Birth rate has to fall • And death rate has to increase.

31. Density Factors of a Population • Density Dependent Factor-Factors that have a stronger effect with increasing population. • Disease • Predators • Parasites • Competition for food • Density Independent Factor-Affects the population regardless of density: • Volcanic Eruptions • Storms • Temperatures • Drought

32. Human Population • Demography-Study of human population size, density and distribution • United States Census is taken every 10 years

33. Human Population • Human growth is different from other organisms because humans have the ability to change their environment • Found cures for diseases • Found methods to produce food • Been able to provide clean water

34. Human Population • Birthrate-Number of live births per 1000 people in 1 year • Death rate-Number of deaths per 1000 people in 1 year • Immigration-People moving into a population • Emigration-People moving out of a population • (Birthrate + Immigration) – (Death rate + Emigration) = Population Growth Rate (PGR) • If the PGR is positive then the population is growing • If the PGR is negative then the population is shrinking

35. Age Structure (Histogram) • Age Structure-Proportions of the population that are in different age groups • Age structure graph shows how many males and females there are in each age group

36. Agriculture/aquaculture

37. Agriculture • Agriculture is the cultivation of organisms for human benefit to sustain life • Key development in the rise of human civilization • Raising domesticated species

38. Traditional Agriculture • Traditional farming – The mixed farm of livestock and crops. Uses crops and animals to feed each other • Farmers use crops to feed livestock • Farmers use excrement from livestock as fertilizers for crops

39. Traditional Agriculture • Benefits: • Many different types of crops grown. Replenishes the soil • Employs people • Disadvantages: • Reliance upon rainfall. No rainfall = drought

40. Sustainable Agriculture • Sustainable agriculture is a process where farmers use ecological principals to farm • Provides a healthy environment for people over a long period of time and reduce degredation

41. Sustainable Agriculture • Advantages: • Economically sustainable • Environmentally sound • Good for families and communities • Disadvantages: • Reduced productivity • Requires higher investments • Requires more knowledge to be successful

42. Aquaculture • Aquaculture-Farming of aquatic organisms: • Fish • Crustaceans • Mollusks • Aquatic plants • Requires raising controlled marine populations under controlled conditions

43. Introduction • Definition: Rearing of aquatic organisms under controlled or semi-controlled conditions. • Intensive Aquaculture: Highly controlled, high density, RAS, raceways, confined (industrialized) • Extensive Aquaculture: Minimal control, lower density, ponds, third world

44. Introduction: What Can We Grow? Fish Husbandry • Food—finfish, crustaceans, mollusks, frogs, algae • Baitfish—fathead minnow, golden shiner • Sportfish—bass, bluegill, walleye • Ornamentals—tilapia, goby, • Feeder fish—goldfish, shiner, minnow • Biological supply houses

45. Photograph by HBOI Photograph by HBOI Fisheries stock enhancement Bait production Photograph by HBOI Photograph by HBOI Biomedical Ornamentals

46. How many of you eat seafood? • About 40% of the seafood we eat is from aquaculture farms • Aquaculture production in the United States is valued at $1.1 billion • In Florida: $70-100 million

47. Commercially Cultured Species Catfish Tilapia Trout Salmon Striped Bass Oysters Clams Shrimp Photograph by HBOI

48. Why Culture Fish? • Finite Resource—overfishing and habitat destruction • Fuel Cost $$$ • Health Consciousness (protein, micronutrients)

49. Why Culture Fish? • An advantage of aquaculture in terms of productivity compared to that of land systems is that •  1. a water environment provides a three-dimensional growing space • 2.  aquatic species are cold-blooded and therefore convert more food to growth rather than spending energy on maintaining body temperature •  3. aquatic species have a higher flesh-to-bone ratio than land species have •  Efficiency (see next slide)

50. Feed Conversion (grain/flesh) • Beef cattle on feedlot 8:1 • Swine 3.3:1 • Poultry 2.25:1 • Rainbow trout 1.5:1 • Tilapia 1.25:1 • Why ARE fish so efficient?