Featured Research

from universities, journals, and other organizations

Drought in amazon rain forest: Continued studies may help predict future health of rain forests

Date:
May 19, 2014
Source:
South Dakota State University
Summary:
Two major droughts within a five-year period have done significant damage to the Amazon forest in Brazil, but analyzing how the forest has responded may help researchers predict the long-term impact of global warming, according to a research scientist. The study will focus on the southern Brazilian Amazon including the states of Acre, Rondônia and Mato Grosso. These areas were affected by both droughts and are heavily deforested yet have scattered fragments of remaining forest.

Research scientist Izaya Numata, right, of the Geographic Information Sciences Center of Excellence at South Dakota State University, and his Brazilian research assistant perform field research on pastures in Rondônia, Brazil, as part of Numata’s dissertation work. Over the next three years, he and a team of scientists will study how two droughts in five years have affected forest fragments, such as those in the background.
Credit: Image courtesy of South Dakota State University

Two major droughts within a five-year period have done significant damage to the Amazon forest in Brazil, but analyzing how the forest has responded may help researchers predict the long-term impact of global warming, according to research scientist Izaya Numata of the Geographic Information Science Center of Excellence at South Dakota State University.

Related Articles


Through a three-year, $602,349 NASA grant, Numata and a team of scientists will assess how the 2005 and 2010 droughts affected the forest edges and to what extent deforestation patterns affect the trees' vulnerability.

His team consists of senior scientist Mark Cochrane, a wildfire expert; assistant professor Jeppe Kjaersgaard, an agricultural engineer at the SDSU Water Resources Institute; and professor Sonaira S. da Silva of the Federal University of Acre in Brazil. One postdoctoral researcher will also work on the project.

The study will focus on the southern Brazilian Amazon including the states of Acre, Rondônia and Mato Grosso. These areas were affected by both droughts and are heavily deforested yet have scattered fragments of remaining forest.

Slowing deforestation

The Brazilian Amazon covers 60 percent of the country, an area half the size of the continental United States, Numata explained. By 2013, deforestation that began in the 1970s had cleared an area equivalent to North Dakota, South Dakota, Minnesota and Iowa combined.

Farmers in the deforested areas raise cattle, but more recently have planted soybeans, Numata explained. To expand production, they simply cleared more forest area.

In the last decade, the Brazilian government has been enforcing regulations that have helped slow deforestation, he added. Consequently, farmers "must now manage their land more sustainably."

Analyzing fragmentation of forest

"The prolonged drought in 2005 caused a lot of tree mortality," Numata explained, adding the subsequent drought in 2010 was far more severe and extensive.

Researchers at the California Institute of Technology found that the forest canopy had not yet recovered from the 2005 drought when the even stronger 2010 event occurred. This double-whammy may have lasting-effects on the forest, Numata added.

However, the impact will likely be different based on the shape and size of the forest fragments, according to Numata. Trees near the edge of forest fragments are subjected to more solar radiation, lower humidity and stronger winds. This then causes thinning of the tree canopy, death of trees and plants and significant changes in the species the forest can support.

These edge effects vary based on distance from edge to interior forest and time since the creation of forest edge, Numata explained. Since the southern Amazon is intensively deforested and fragmented, Numata hypothesizes that these forest edges are more vulnerable to drought than trees in the interior forest.

To verify this, he and his team will examine Landsat satellite data from 1997 through 2014 to document when forest fragments were created and how their size and age affect their reaction to drought.

After characterizing the forest fragments spatially, the team will visit specific sites across the gradient of intensity of both droughts and forest fragmentation in July to measure vegetation at regular intervals from the forest edge, according to Numata. Then the field results will be compared with spatial and temporal changes in forest biophysical conditions such as evapotranspiration, phenology and greenness derived from Landsat for those areas affected by the drought and those that were not.

"A drought event drastically reduces available water and affects vegetation health," he said.

Based upon the results, the scientists will try to predict the vulnerability and response of the forest to future changes in climate and land cover.

"The forest edges may serve as indicators of the tipping point at which future drought events and climate change can cause a lot of ecological changes to the Amazonian system," Numata added.


Story Source:

The above story is based on materials provided by South Dakota State University. Note: Materials may be edited for content and length.


Cite This Page:

South Dakota State University. "Drought in amazon rain forest: Continued studies may help predict future health of rain forests." ScienceDaily. ScienceDaily, 19 May 2014. <www.sciencedaily.com/releases/2014/05/140519215041.htm>.
South Dakota State University. (2014, May 19). Drought in amazon rain forest: Continued studies may help predict future health of rain forests. ScienceDaily. Retrieved October 26, 2014 from www.sciencedaily.com/releases/2014/05/140519215041.htm
South Dakota State University. "Drought in amazon rain forest: Continued studies may help predict future health of rain forests." ScienceDaily. www.sciencedaily.com/releases/2014/05/140519215041.htm (accessed October 26, 2014).

Share This



More Earth & Climate News

Sunday, October 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

EU Gets Climate Deal, UK PM Gets Knock

EU Gets Climate Deal, UK PM Gets Knock

Reuters - Business Video Online (Oct. 24, 2014) — EU leaders achieve a show of unity by striking a compromise deal on carbon emissions. But David Cameron's bid to push back EU budget contributions gets a slap in the face as the European Commission demands an extra 2bn euros. David Pollard reports. Video provided by Reuters
Powered by NewsLook.com
Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Raw: Tornado Rips Roofs in Washington State

Raw: Tornado Rips Roofs in Washington State

AP (Oct. 24, 2014) — A rare tornado ripped roofs off buildings, uprooted trees and shattered windows Thursday afternoon in the southwest Washington city of Longview, but there were no reports of injuries. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Fast-Moving Lava Headed For Town On Hawaii's Big Island

Fast-Moving Lava Headed For Town On Hawaii's Big Island

Newsy (Oct. 24, 2014) — Lava from the Kilauea volcano on Hawaii's Big Island has accelerated as it travels toward a town called Pahoa. Video provided by Newsy
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