Biodiversity Notes & Links to more information
I. What is biodiversity?
A. “bio” means life, living things
1. “diversity” = variety, differences
2. Biodiversity (BD) = the variety or richness of living things
B. There are a 3 ways scientists look at biodiversity…
1. Genetic BD
a. The variety of types within a single species
i. Ex. diff. breeds of dog
ii. Ex. difference in eye, hair color in humans
2. Species BD
a. Variety of species living in an area
i. Ex. diff. species living around Eagle School
3. Ecosystem BD
a. Variety or diff. types of ecosystems
i. Ecosystems = community (biotic) + abiotic (weather, temp. water, sun)
ii. Ex. tundra, desert, prairie etc.
iii. Generally, ecosystems with warmer temps and higher rainfall have greatest degree of species biodiversity
(a) Ex. rainforests, coral reefs = high BD
(b) Deserts & tundra = low BD
II. Why is biodiversity important?
A. Biodiversity helps to provide basic needs for food, shelter, water, and air (or ecosystem services)
1. Generally, the greater the variety of plants, the greater the variety of animals that they support for food, shelter, air,
a. Photosynthesis provides oxygen for respiration and food for primary consumers
b. Plants offer shelter (ex. building materials, nesting cavities) and space (structure for spider webs)
c. Plants can provide water (ex. flower nectar, tree sap or leaves that contain water)
d. Pollinators ensure that plants can reproduce
2. Biodiversity is important to humans because we depend on many different species to provide food, shelter, clean
air and water, clothing, energy building materials, medicines, etc.
B. Biodiversity helps to maintain stable, healthy ecosystems.
1. The more organisms within an ecosystem, the more interdependencies among them.
a. When there are very few plants in an ecosystem, the loss of one species can have a very strong impact on the organisms that depend on it.
i. Milkweed bugs and monarchs depend entirely on milkweed plants. (When an organism depends on a single food source, they are called specialists). If the milkweed were to die out in an area, so would the milkweed bugs and monarchs that depend on them for food.
ii. If the lawn were to die, all the species that depended on it would either die or move.
b. The more biodiverse an ecosystem, the less of an impact the loss of a species will have
i. The loss of one species of grass among many others will not negatively affect a grasshopper that can eat more than one type of plant. (Grasshoppers are an example of a generalist, or an organism that can eat a variety of foods).
ii. The Playground Prairie has over 15 different species of plants. If one were to die out, generalists that ate that plant might be able to get their food from the other remaining plants and still live quite well in that community.
2. A diversity of plants helps prevent erosion and improve air and water quality.
a. A healthy root system can prevent soil erosion during heavy rains and preserve nutrient-rich topsoil.
b. Plants help filter toxins & pollutants from water
c. Plants use carbon dioxide to make their own food and help remove excess carbon dioxide from the air.
III. Threats to biodiversity (the purple links take you to webpages on these subjects)
A. Overexploitation or overusing resources by a growing human population causing the largest mass extinction since the age of dinosaurs
1. 7 billion people on the planet need more space to live and grow food
2. Endangering species due to hunting and collecting
B. Habitat loss
1. New building construction removes habitat
2. Natural disasters can destroy habitat (i.e. tsunami, fires)
3. Destruction of biodiverse ecosystems such as the rain forest (deforestation) to grow monoculture crops for humans
1. Air pollution
a. Increased carbon dioxide and fewer plants (from deforestation) to convert it to oxygen creates global warming & climate change
b. Power plants produce gases that cause acid rain and increase freshwater and ocean acidity
i. Increased acidity in ocean waters kill coral reefs, which are among the most biodiverse in the world
c. Large populations of cows and other livestock produce methane, which is the major contributor to climate change and global warming
2. Water pollution
a. Fertilizer run-off from farm fields into the water results in polluted water and ocean dead zones
b. Dumping of factory waste into water
D. Invasive species
1. Any organism that is not native to an ecosystem and causes harm either by outcompeting the native species or by consuming them
IV. Conserving Biodiversity
A. Create laws that protect the environment
1. Endangered species act protects habitats important to organisms that are endangered of extinction
2. Water and air pollution laws that reduce dumping waste into the air and water
B. Restore ecosystems
1. Clean up and restore damaged ecosystems
a. BP was required to clean up the oil and restore the ecosystems damaged by the oil spill
C. What I can do to conserve biodiversity? (Lots! Here's a few things, but I bet you can think of more. You CAN make a difference.)
a. water usage… take shorter showers, fill dishwasher before running it, don’t water your sidewalks
b. electricity usage…..turn off lights every time you leave room; unplug your TV, computers, radios, game systems etc. after using (even when their turned off, they use electricity); wear warmer clothing in winter so you can turn down
c. fuel usage…. Walk and bicycle more, drive less, combine errands
d. meat consumption… the more meat you eat, the more space is used to grow the corn and alfalfa that feeds the
animals that also take up space and reduce biodiversity
e. food waste – don’t take more than you can eat, save your leftovers for later, drink all the milk in your cereal bowl
f. stuff - do you really need as much stuff as you buy? How long before you don't use it anymore?
2. Reuse ….
a. clothing – buy some of your clothes at used clothing stores or have a clothes trading party
b. fix things that are broken rather than throwing them out and replacing them
a. compost your vegetable waste so that microorganisms can decompose it
b. separate your garbage into the recycling
c. recycle your compost and plant a vegetable garden (that's about as fresh and local as you can get!)
a. Help to bring back lost habitat by cleaning up, removing invasive plants, replanting and caring for land to make it more inviting to a greater number of native species
Readings on Biodiversity
Click on this Ecokids link to go to another good site for kids on Biodiversity