. Earth Science News .
WOOD PILE
A plant present in Brazil is capable of colonizing deforested areas
by Staff Writers
Sao Paulo, Brazil (SPX) Aug 10, 2016


File image.

Tropical reforestation programs tend to prioritize native pioneer tree species, which colonize disturbed or cleared areas thanks to their high reproductive capacity and rapid growth, among other characteristics.

According to experts, these species facilitate the transition from deforested land to secondary forest. They stabilize terrain and enhance connectivity between remaining forest fragments by increasing soil permeability, as well as fostering the formation of networks of pollinators and plant seed dispersers.

Despite the ecological importance of pioneer tree species, little is known about their ability to maintain genetic diversity in native populations or the dynamics of gene flow between widely separated forest fragments, according to Rodolfo Jaffe, a researcher at the Vale Institute of Technology (ITV) in Brazil.

"Knowledge of these species' genetics is fundamental to more efficient reforestation or rehabilitation of key ecosystemic functions in the short and medium term. Ecosystems that are rehabilitated using native pioneer tree species will obviously never be the same as the original ones, but the goal is to get as close as possible," said Jaffe.

In partnership with colleagues at the University of Texas at Austin in the United States, Jaffe studied the genetic diversity and differentiation patterns of the native pioneer understory tree Miconia affinis in Panama, Central America. An evergreen with heights typically ranging from 3 m to 6 m, M. affinis is widely distributed in the Neotropics from Mexico to Brazil.

"The Panama Canal region is a global biodiversity hotspot that has lost over 30% of its forest cover to agropastoral development during the past 50 years, leading to high levels of erosion and sediment deposition in streams and canals with adverse effects on the region's water-holding capacity," Jaffe said.

"The government of Panama wants to reforest degraded and cleared areas to reduce erosion and sediment buildup in the Canal. The native pioneer species present in the region are considered suitable candidates for use in restoration programs."

To find out whether deforested areas form a barrier to populations of M. affinis, the researchers collected leaf tissue from approximately 30 reproductive trees bearing inflorescences or infructescences in 11 different populations along the Panama Canal.

Next, they extracted DNA from the leaf tissue and genotyped the trees using microsatellite molecular markers, also called simple sequence repeats - short segments of DNA that indicate the most recent evolutionary variations in an individual organism.

They also estimated the influence of geographic distance, elevation and deforestation on the genetic structure and differentiation of the M. affinis populations studied. To do so, they used high-resolution maps of forest cover and elevation in the Panama Canal region, as well as landscape genetics tools.

Their statistical analyses showed that the genetic differentiation of this tree species, which frequently colonizes forest gaps, riparian areas and exposed hillsides, significantly increased with elevation and geographic distance between populations.

"This result means populations of the species become more genetically differentiated as the distance between them increases, whereas the closer they are, the more similar they are genetically. This effect is called the isolation-by-distance pattern and is expected for most plant populations," Jaffe said.

The analyses also showed higher levels of genetic diversity within populations of M. affinis and lower levels of genetic differentiation between populations than for many other pioneer species.

"High genetic diversity within populations and low differentiation between populations are probably due to the species' propensity to colonize deforested landscapes, leading to increased connectivity among populations throughout the region," they say.

The researchers also found that elevation influences genetic differentiation in populations of M. affinis. Populations inhabiting relatively higher altitudes are more genetically differentiated than populations at lower altitudes regardless of the distance between them.

"One reason for this may be that the lower temperature and heavier rainfall at higher elevations compared with lower ones affect flying conditions and the abundance of pollinators and seed dispersers," Jaffe said.

M. affinis is visited by a wide array of social and solitary bees, and seeds from its fruits are dispersed by a variety of birds, bats and monkeys.

Temperature and precipitation also cause earlier flowering at higher altitudes. "As a result, pollinators tend to stay where flowering occurs first, instead of visiting populations at lower altitudes where flowering hasn't begun. Differences in phenology, the timing of fruiting and flowering, can influence genetic structure," Jaffe said.

The researchers did not find evidence that deforestation affects genetic differentiation in populations of M. affinis. A potential explanation is that the high dispersal and colonization capacity of this species promotes gene flow across the region regardless of forest cover.

"Our results suggest human-altered landscapes along the Panama Canal do not limit gene flow between isolated forest populations. Pollinators and seed dispersers are able to visit the trees, crossing deforested areas and pollinating populations located in other areas," Jaffe said.

They estimated an average lifespan of 64.3 years for M. affinis, which generates seeds for the first time at an average of about six years old, and observed that the species is capable of maintaining a high level of genetic diversity regardless of the amount of surrounding forest.

"These characteristics in aggregate make M. affinis an excellent candidate for use in reforestation programs," Jaffe said.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
Fundacao de Amparo a Pesquisa do Estado de Sao Paulo
Forestry News - Global and Local News, Science and Application






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
WOOD PILE
The missing link in carbon accounting
Washington DC (SPX) Aug 05, 2016
While tropical forests continued to decline, a remarkable change is happening: tree cover on agricultural land has increased across the globe, capturing nearly 0.75 Gigatonnes carbon dioxide every year. A new study titled "Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets" provides insights into the patterns of this ... read more


WOOD PILE
Lost in translation: Chinese tourist taken for refugee in Germany

Researchers work to understand causes of search and rescue in the Arctic

Study shows heat dangers of inflatable bounce houses

Search for 20 feared dead after India bridge collapse

WOOD PILE
Hot 'new' material found to exist in nature

Flexible building blocks of the future

A mini-antenna for the data processing of tomorrow

New metamaterials can change properties with a flick of a light-switch

WOOD PILE
Global warming, a dead zone and surprising bacteria

'Alarming' bleaching of Maldives corals: conservationists

Looking back into the future: Are corals able to resist a declining pH

Uncovering what lies beneath the oceans

WOOD PILE
NASA Maps Thawed Areas Under Greenland Ice Sheet

Antarctic sea ice may be a source of mercury in southern ocean fish and birds

Lack of water likely caused extinction of isolated Alaska mammoths

St. Paul Island mammoths most accurately dated 'prehistoric' extinction ever

WOOD PILE
French wheat output headed for 30-year low

Pesticides used by beekeepers may harm bees' gut microbiota

Sunflowers move by the clock

Trading farmland for nitrogen protection

WOOD PILE
First evidence of legendary China flood may rewrite history

Mexico hunts for missing after landslides kill 45

Flooding, mudslide warning as hurricane aims for Belize

Volcanic eruptions in Indonesia hit air travel

WOOD PILE
South Sudan accepts deployment of regional force: IGAD

US, Senegal troops wind up first-ever emergency exercise

Libya unity government demands explanation over French troops

Five missing soldiers found in Nigeria: army

WOOD PILE
Tracking down the first chefs

The great evolutionary smoke out: An advantage for modern humans

Researchers find evidence of animal butchering by Stone Age hominins

Fresh look at burials, mass graves, tells a new story of Cahokia









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.