Featured Research

from universities, journals, and other organizations

Human rules may determine environmental 'tipping points'

Date:
April 15, 2011
Source:
University of Notre Dame
Summary:
A new paper suggests that people, governments, and institutions that shape the way people interact may be just as important for determining environmental conditions as the environmental processes themselves.

A new paper appearing in the Proceedings of the National Academy of Sciences (PNAS) suggests that people, governments, and institutions that shape the way people interact may be just as important for determining environmental conditions as the environmental processes themselves.

Related Articles


"Tipping points," qualitative changes in an ecosystem that often result in reduced ecosystem health and are difficult and costly to reverse increasingly concern environmental scientists.

The prevailing assumption among scientists has been that tipping points are fixed values. However, a unique research collaboration involving a team of biologists and economists that included University of Notre Dame ecologist David Lodge, Michigan State University economist Richard Horan, Arizona State University economist Eli Fenichel and Bethel College biologist Kevin Drury, indicates that these tipping points are not fixed in human-impacted ecological systems and depend, instead, on human responses to a changing environment.

The authors point out many instances of tipping points that resulted in catastrophic changes in ecosystems, such as climate change, collapsed freshwater and marine fisheries and changes wrought by invasive species. For example, the invasive species sea lamprey changed the Great Lakes from an environment productive of lake trout and whitefish to a collapsed fishery. If not for the $17 million spent annually by the United States and Canada to control them, sea lamprey would continue to devastate Great Lakes fisheries.

In the research described in the PNAS paper, the researchers studied invasive rusty crayfish, which have transformed many Michigan and Wisconsin lakes from luxuriant underwater forests inhabited by many smaller animals that supported sport fish to clear-cut forests with diminished production of sport fish. This outcome occurred despite the fact that there are many fish like smallmouth bass that readily consume crayfish.

"Our work explored whether a shift from one lake condition with excellent habitat to another lake condition with barren lake bottom is the inevitable result of invasion by crayfish or whether it is just one possible outcome," Lodge said. "In other words, we asked whether we humans need to passively accept undesirable outcomes or whether, instead, the institutions and rules by which we make decisions can change the landscape of possibilities."

The institutional rules shape the relationship among managers, users, and ecological systems. If the system is mapped using only ecological characteristics, then managers may not account for human responses to change, such as changing decisions about whether or how much to fish as fishing quality changes.

The research results showed that tipping points in human-impacted ecosystems are affected by regulatory choices that influence human behavior.

"This gives us reason for optimism: if we give regulators sufficient flexibility it may be possible and cost-effective to manage ecological systems so that only desirable ecological outcomes arise and tipping points are eliminated," Horan said.

"Our results also create concern: if natural resource managers' policy choices are overly restricted, then it might be too difficult or costly to avoid tipping points," Fenichel added.

In particular, the researchers stress that their results highlight the importance of giving strong institutional support to regulatory agencies that aim to enhance societal wellbeing.

"Without strong institutional support, tipping points might disappear but not in a good way," Horan said. "Suppose lake managers invest in crayfish removal but do not properly alter the behavior of anglers, who overharvest fish. In such a scenario, crayfish removal may be ineffective at restoring the lake system if anglers continue to pull the ecosystem toward an undesirable state. Investing in crayfish removal without also addressing angler behaviors is therefore a waste of money. Why would we invest to protect the system from crayfish if we are unable or unwilling to protect the system from humans?"


Story Source:

The above story is based on materials provided by University of Notre Dame. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. D. Horan, E. P. Fenichel, K. L. S. Drury, D. M. Lodge. Managing ecological thresholds in coupled environmental-human systems. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1005431108

Cite This Page:

University of Notre Dame. "Human rules may determine environmental 'tipping points'." ScienceDaily. ScienceDaily, 15 April 2011. <www.sciencedaily.com/releases/2011/04/110415154736.htm>.
University of Notre Dame. (2011, April 15). Human rules may determine environmental 'tipping points'. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2011/04/110415154736.htm
University of Notre Dame. "Human rules may determine environmental 'tipping points'." ScienceDaily. www.sciencedaily.com/releases/2011/04/110415154736.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Arctic Warming Twice As Fast As Rest Of Planet

Arctic Warming Twice As Fast As Rest Of Planet

Newsy (Dec. 18, 2014) The Arctic is warming twice as fast as the rest of the planet, thanks in part to something called feedback. Video provided by Newsy
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
Ivory Trade Boom Swamps Law Efforts

Ivory Trade Boom Swamps Law Efforts

Reuters - Business Video Online (Dec. 17, 2014) Demand for ivory has claimed the lives of tens of thousands of African elephants and now a conservation report says the illegal trade is overwhelming efforts to enforce the law. Amy Pollock reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins