A new study looked at the implications ecosystems thriving within the liquid of a carnivorous pitcher plant had for the future of our environment.
The researchers of the study pointed out that water within these plants is subject to the same "tipping point" as larger lakes, an issue that is being given particular notice this Earth Day, the National Science Foundation reported. The study provides new insight into what triggers these tipping points in the first place.
"Human societies, financial markets and ecosystems all may shift abruptly and unpredictably from one, often favored, state to another less desirable one," said Saran Twombly, program director in NSF's Division of Environmental Biology, which funded the research. "These researchers have looked at the minute ecosystems that thrive in pitcher plant leaves to determine early warning signals and to find ways of predicting and possibly forestalling such 'tipping points.'"
Life in both lakes and pitcher plants can be disturbed by an overabundance of nutrients, often caused by fertilizers and pollution, These changes can lead to "tipping points" characterized by dramatic changes.
"The first step to preventing tipping points is understanding what causes them," said Aaron Ellison, an ecologist at Harvard Forest and co-author of the paper. "For that, you need an experiment where you can demonstrate cause-and-effect."
The research team continuously added organic matter (comparable to decomposing algae caused by increase nutrients) to the tiny aquatic ecosystems containing about a quarter of an ounce of rainwater. Oxygen levels within these plants are controlled by photosynthesis and the behavior of inhabiting organisms in the same way that they are in larger bodies of water. Since the plant's ecosystem was composed of almost exclusively bacteria, it allowed scientists to watch the changes as if "fast forwarding through a video."
"A bacterial generation is 20 minutes, maybe an hour. In contrast, fish in a lake have generation times of a year or more," Ellison said. "We would need to study a lake for 100 years to get the same information we can get from a pitcher plant in less than a week."
To create the nutrient overload experience by the ecosystem, the team fed wasps to the carnivorous plants.
"That's equivalent to a 200-pound person eating one or two McDonald's quarter-pounders every day for four days," Ellison said.
The scientists determined the "tipping point" occurred about 45 minutes after the start of feeding, and this discovery could help determine warning signs in large bodies of water.
"Tipping points may be easy to prevent," says Ellison, "if we know what to look for."
The findings were published in a recent edition of the journal Proceedings of the National Academy of Sciences.
