Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Forest diversity from Canada to the sub-tropics influenced by family proximity

Discovery could impact how conservation, management decisions are made

How species diversity is maintained is a fundamental question in biology. In a new study, a team of Indiana University biologists has shown for the first time that diversity is influenced on a spatial scale of unparalleled scope, in part, by how well tree seedlings survive under their own parents.

Data from over 3 million trees in the eastern half of the US were aggregated into two-degree-latitude-by-longitude cells in order to study regional patterns of conspecific negative density dependence, a process where the mortality of a species rises in coincidence with its increasing abundance. Credit: Indiana University

Scientists have long considered conspecific negative density dependence (CNDD), a process where the mortality of a species rises in coincidence with its increasing abundance, to be a key mechanism maintaining diversity at the local scale. In new research to be published Friday in the journal Science, the IU researchers show that this mechanism is driving diversity from the boreal forests to sub-tropical forests.

The report, "Conspecific negative density dependence and forest diversity," is authored by Daniel Johnson, a doctoral student in the IU Bloomington College of Arts and Sciences' Department of Biology. Co-authors are Wesley T. Beaulieu, also a doctoral student in the Department of Biology, and biology professors James D. Bever and Keith Clay, Johnson's major advisor.

Their work analyzed data on forest composition from over 200,000 plots containing more than 1.3 million trees and from paired plots containing over 1.7 million seedlings of 151 different tree species. The plots were located from the Canadian border south to Florida and from the Atlantic coast to the 100th meridian and covered over 1.5 million square miles. The U.S. Forest Service spends about $62 million each year to gather the publicly available forest inventory data used in the IU study.

"We are now able to provide robust evidence that CNDD is pervasive in forest communities from boreal to sub-tropical regions and that it can significantly affect the relative abundance and richness of species with and between forests," Johnson said. "And we now see that the ability to which one tree species can sustain itself in the same area has profound impacts on the diversity of species at a spatial scale that has not been attainable previously. This is the first time it's been shown to be happening not just at a local spatial scale but over the entire eastern US."

The concept of CNDD is based on the well-known Janzen-Connell hypothesis, which proposes that the close proximity of adults reduces seedling survival of that species through increased attack by host-specific pests and pathogens.

Studies of CNDD in the past have mostly focused on forest communities at single sites or of a single species, with the most recent work showing that in tree species, composition and abundance can be influenced by CNDD at the scale of individual trees.

"Local interactions have previously been considered to affect species diversity at a local scale, but our findings indicate that local interactions feed back to species richness and abundance over much larger geographical scale, spanning most of eastern North America," Johnson said.

Evidence that local interactions underlie regional species richness is in contrast to the current understanding that patterns of forest diversity are primarily driven by temperature, precipitation and other physical aspects of the environment. This discovery has implications for how forest modeling is conducted and conservation and management decisions are made.

For more information or to speak with Johnson or other co-authors, please contact Steve Chaplin, IU Communications, at 812-856-1896 or Tweeting IU science news: @IndianaScience

Steve Chaplin | EurekAlert!
Further information:

More articles from Agricultural and Forestry Science:

nachricht Forest Management Yields Higher Productivity through Biodiversity
14.10.2016 | Technische Universität München

nachricht Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

New method increases energy density in lithium batteries

24.10.2016 | Power and Electrical Engineering

International team discovers novel Alzheimer's disease risk gene among Icelanders

24.10.2016 | Life Sciences

New bacteria groups, and stunning diversity, discovered underground

24.10.2016 | Life Sciences

More VideoLinks >>>