Tuesday, June 5, 2012
Biodiversity Loss: A Major Driver of Ecosystem Change -Professor David Hooper
When I first heard that we could get extra credit for our biology class by attending an ecology lecture by Professor David Hooper I thought, why wouldn’t I go? This is the first professional in the field of biology I have ever heard of with my same last name!
Professor Hooper began his lecture by posing the question, “Do changes in diversity effect ecosystem processes?” He then further broke this question down into three more questions: 1) What are the magnitudes of effects on processes relative to other environmental changes? 2) What are the effects on things that people care about? 3) How are ecosystems actually changing?
To explain the answer to his first question, he went into details about his recently published paper, “A global synthesis reveals biodiversity loss as a major driver of ecosystem change”. This paper was a meta analysis of 192 studies containing 574 experiments all following a specific criteria. Hooper looked at productivity vs. species richness (SR) of primary producers and decomposition vs. SR of primary producers as well as vs. consumers. Overall he found that with species loss productivity decreases and these effects on productivity were comparable to the effects of other environmental changes. When looking at decomposition it was found that a decrease in litter diversity did not show significant change in decomposition while a change in consumer levels did show a change. All of these results showed high variability.
His second question was explained by looking at different kinds of ecosystem services, excluding cultural services. In the end, this question had mixed results because ecosystem services are hard to quantify and mean different things to different people.
Hooper concluded with answering his third question and saying that there is a need for further research on a larger scale so that we will better be able to look at and understand the connection between biodiversity effects and ecosystem changes in the real world.