Drought sensitivity shapes species distribution patterns in tropical forests

May 14, 2007

Looking at a rainforest it’s easy to see that there are hundreds of different tropical plant species that inhabit the forest. Although the patterns of plant distributions in tropical forests have been widely studied, the reasonings behind these patterns are not as well known. This study, published in Nature, explores these patterns.

A contingent of researchers from around the world, including Panama, Germany, USA and Canada, have uncovered that tropical plant species distribution patterns are linked to the plant’s drought sensitivity.

For this study, the researchers conducted irrigation experiments on 48 native tree and shrub species to determine drought sensitivity between dry and irrigated conditions, which confirmed that species vary widely in drought sensitivity. The researchers also assessed regional plant species distribution across two large plots on opposite sides of the Isthmus of Panama. Through this assessment it was found that the plant’s densities at the dry Pacific side compared to the wet Atlantic side correlated negatively with drought sensitivity.

"Our results suggest that niche differentiation with respect to soil water availability is a direct determinant of the distributions of tropical plant species," said Dr. Mel Tyree, University of Alberta researcher.

Although tropical plant species’ reactions to environmental factors, namely light and nutrients, have been experimentally assessed in numerous studies, only a few have quantitatively linked this data to distribution patterns. These studies were restricted to a small number of species, precluding analysis of the importance of environmental factors across the community. Thus, these findings represent the most thorough study so far linking tropical plant species distribution patterns with species’ reactions to an environmental factor at the community level

"The results presented here emphasize the sensitivity of tropical forests to water availability," said Dr. Tyree. "Therefore, changes in soil moisture availability caused by global climate change and forest fragmentation are likely to alter tropical species distribution, community composition and diversity."

Source: University of Alberta

Explore further: Colorful caterpillar chemists may signal new useful plant compounds

Related Stories

Creating a fast-track for accurately classifying plants

October 1, 2015

It can take botanists decades to accurately classify plants after they've collected and stored away samples from the wild. But now Oxford University researchers have developed a technique to streamline the process—and it's ...

Large trees—key climate influencers—die first in drought

September 29, 2015

In forests worldwide, drought consistently has had a more detrimental impact on the growth and survival of larger trees, new research shows. In addition, while the death of small trees may affect the dominance of trees in ...

The origin and spread of 'Emperor's rice'

September 25, 2015

Black rice has a rich cultural history; called "Forbidden" or "Emperor's" rice, it was reserved for the Emperor in ancient China and used as a tribute food. In the time since, it remained popular in certain regions of China ...

Recommended for you

Most EU nations seek to bar GM crops

October 4, 2015

Nineteen of the 28 EU member states have applied to keep genetically modified crops out of all or part of their territory, the bloc's executive arm said Sunday, the deadline for opting out of new European legislation on GM ...

The dark side of Nobel prizewinning research

October 4, 2015

Think of the Nobel prizes and you think of groundbreaking research bettering mankind, but the awards have also honoured some quite unhumanitarian inventions such as chemical weapons, DDT and lobotomies.

Internet giants race to faster mobile news apps

October 4, 2015

US tech giants are turning to the news in their competition for mobile users, developing new, faster ways to deliver content, but the benefits for struggling media outlets remain unclear.

Fusion reactors 'economically viable' say experts

October 2, 2015

Fusion reactors could become an economically viable means of generating electricity within a few decades, and policy makers should start planning to build them as a replacement for conventional nuclear power stations, according ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.