1 / 16

Sustainability

Sustainability. Chapter 12. Sustainability. A sustainable activity is one that can be continued or repeated for the foreseeable future How much human activity is sustainable?. Sustainability. Can we allow the global human population to continue to grow?.

jadon
Download Presentation

Sustainability

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sustainability Chapter 12

  2. Sustainability • A sustainable activity is one that can be continued or repeated for the foreseeable future • How much human activity is sustainable?

  3. Sustainability Can we allow the global human population to continue to grow? What resources do we require, and how do we acquire them? Famine, disease, war

  4. Sustainability Peruvian anchoveta fishery Can we continue to harvest fish faster than they can replace themselves? Maximum sustainable yield Fixed quota Fixed effort

  5. Sustainability Can we continue to harvest agricultural crops if the quality and quantity of soil deteriorates? New soil - 0.2 t/ha/yr Erosion - 2.0 t/ha/yr Dust Bowl in central U.S. - 1930s

  6. Poor Agricultural Practices • Farming steep slopes • Removing fence rows • Moldboard plowing (in fall) • Overgrazing • Farming natural waterways • Compacting soil with large machines • Lack of crop rotation

  7. Sustainability Can we continue to demand and use more water despite its chronic scarcity and increasing contamination? Fresh water recycled by water cycle, but humans now use >1/2 of accessible supply Few water resources remain pristine

  8. Lowering the Water Table Original water table Initial water table Cone of depression Lowered water table

  9. Groundwater Overuse Groundwater Overdrafts: High Moderate Minor or none

  10. Saltwater Intrusion Major irrigation well Well contaminated with saltwater Water table Sea Level Salt water Fresh groundwater aquifer Interface Interface Saltwater Intrusion Normal Interface

  11. CALIFORNIA NEVADA UTAH Shasta Lake Sacramento River Sacramento North Bay Aqueduct San Francisco Fresno South Bay Aqueduct Colorado River Los Angeles Aqueduct ARIZONA California Aqueduct Central Arizona Project Los Angeles Phoenix San Diego Colorado River Aqueduct Tucson MEXICO Transferring Water from One Place to Another • Watershed transfer • California Water Project • Central Arizona Project

  12. Saving Water in the Bathroom

  13. Gray Water Systems

  14. Sustainability Can we continue to use the same pesticides if increasing numbers of pests become resistant to them? Genetic resistance - accelerated selection for resistant individuals

  15. Pesticide Problems • Persistence • Bioaccumulation/biomagnification - DDT and the bald eagle • Nonspecificity Broad spectrum vs. selective pesticides

  16. Biological Controls: Alternatives • Predators or parasites • Attractants (pheromones = sex hormones) • Sterilization • Resistant crops (genetic)

More Related