TBLU - Conservation Biology (Lesson)
Conservation Biology
Conservation biology attempts to slow down the rate at which we are destroying and degrading the Earth's biodiversity through the use of rapid response strategies. More people require more food, and more food requires the use of more land, water, and fossil fuels, all of which impact the environment.
One of the great challenges of humanity's transition from hunter-gatherer societies to cities was feeding a densely packed population. Now that Earth's population has exceeded 7 billion, the challenge is greater than ever, requiring the development of efficient farming and livestock techniques. These techniques have so far allowed the food supply to keep pace with the population. Still, agricultural science is not without its drawbacks including the potential for environmental damage.
The beginning of industrialized agriculture in the mid-and late 20th century became known as the Green Revolution.
The Green Revolution included these developments:
- Increased irrigation infrastructure
- Wide use of pesticides and fertilizers
- High-yield crop varieties (mainly wheat, maize, and rice) are created through breeding and crossbreeding techniques (selective breeding).
Genetic Engineering and Crop Production
Changing segments of an organism's DNA is called genetic engineering or genetic modification, and organisms that are altered are called genetically modified organisms. In the process of genetic modification, genes from an organism with a desired trait are harvested and spliced into the DNA of an existing organism. Ultimately, the combination creates the desired traits. The result of artificially transferring genetic material is known as a transgenic organism. Historically, the technique used to introduce desired traits in existing crops or livestock was selective breeding, but genetic modification differs in its altering of an organism's DNA; it might mix genes from different species with little or no similarities.
Examples of genetically modified crops:
- Bt corn and cotton: Contains a toxin from the Bt bacteria (Bacillus thuringiensis) which acts as an insecticide, removing the need to spray chemicals
- Round-up Ready Cotton: The plant is resistant to Round-Up, a common herbicide so that when the field is sprayed, the weeds are killed and the cotton is not. Click here to learn more about current problems with this variety. Links to an external site.
- Ice-minus strawberries (Frostban): Frost resistant, banned from use in 1986.
- Long-lasting tomatoes: Remain fresh longer
- Golden Rice: Contains vitamin A, a missing nutrient in many developing countries. As shown in the picture, the golden rice is in the upper right, as compared with normal rice in the bottom left.
One way in which biodiversity can be maintained on a global scale is to preserve diverse seed types, including wild varieties. For this purpose, seed banks exist throughout the world. Housing and preserving many seed types is a way to protect seed genetic diversity along with safeguarding our food supply in case of disaster.
RESOURCES IN THIS MODULE ARE OPEN EDUCATIONAL RESOURCES (OER) OR CREATED BY GAVS UNLESS OTHERWISE NOTED. SOME IMAGES USED UNDER SUBSCRIPTION.