BIOL 111 Chapter Notes -Positive Feedback, Rain Shadow, The Green House
Document Summary
The green house effect: global warming is the progressive increase of earth"s average temperature. Presence of carbon dioxide (major source) in the atmosphere leads to a phenomenon called the green house effect. In the absence of excess green house gases, water vapour and carbon dioxide work together to keep the temperature on earth hospitable. Dead plant that are buried before they decompose can produce fossil fuels: most fossil fuels come from carboniferous period, human activities have increased levels of carbon dioxide in the atmosphere. Global warming and photosynthesis: we are also removing organisms that take up excess carbon dioxide. The process that occurs when forests are cleared for logging, farming, and ever expanding human settlement is called. Deforestation (25% of co2 that is released to atmosphere: net rates of photosynthesis (co2 /acr. year) in grasslands and agricultural fields are 30 60% less than rates in forests. Solution: replanting: young trees have faster net photosynthetic rate than older ones.