ECOSYSTEMS AS RESOURCES
I. Why Do We Want to Use Resources Sustainably?
Resources provided by ecosystems sustain life.
There are a limited number of resources in an ecosystem.
Ecosystems are limited in their ability to cycle resources.
II. Ecosystems and Their Goods and Services
A. The Goods
Wood: buildings, paper, furniture
Food: meat, grains, vegetables, fruits, oils
Minerals: phosphorus and nitrogen (for farming), copper (electrical wire),
aluminum (cans, cars), iron, silver, gold, platinum, titanium
Fuel: wood, petroleum, dung, alcohol
Clothing: cotton, rayon, nylon, polyester, fur, leather
Plastics: petroleum, trees (rayon)
B. The Services
1. Maintenance of Hydrologic Cycle:
water infiltrates soil and is absorbed
Water evaporates from soil or evapotranspires from plants. Evaporated water
condenses in the atmosphere and falls to the earth as precipitation. Flooding is
prevented by the functioning of dynamic ecosystems because precipitation is
absorbed by the ecosystem and slowly released.
2. Modification of Climate:
Water absorbs a considerable amount of energy
from the sun as it evaporates. This energy is released when the water condenses.