Navigation Links
Young tropical forests contribute little to biodiversity conservation
Date:12/12/2013

A satellite image of a green swath of tropical forest does not tell the whole story. About half the world's tropical forests are relatively young. Unless protected, they are unlikely to last more than a human generation before falling to bulldozers and chainsaws. These ephemeral secondary forests may contribute little to tree-biodiversity conservation, according to a new report by scientists at the Smithsonian Tropical Research Institute in Panama.

"Secondary forests in the tropics are normally cut within a few decades and very often in less than 10 years," said Michiel van Breugel, post-doctoral fellow at STRI and lead author of the study published Dec. 11 in PLOS ONE. "From the perspective of conserving tree species, this doesn't work." Even 30-year-old forests have a very low percentage of the reproductive trees essential to long-term species survival.

Perhaps the most extensive of its kind in the tropics, van Breugel's study suggests that forests subjected to regular human disturbance may undergo profound, long-lasting tree biodiversity loss. Whereas fallow forests can have a surprisingly high tree-biodiversity, a large proportion of tree species only occur as seedlings and saplings. They do not reproduce before the forests are cleared again.

"A tree only contributes to the conservation of its species when it arrives at a site, establishes, grows and reproduces," said van Breugel.

The research was conducted on the Smithsonian's 700-hectare Panama Canal Watershed Experiment, a long-term research site designed to quantify ecosystem services provided by different land uses.

Van Breugel and colleagues had two questions in mind: First can secondary forests recover their original diversity through natural succession in the long-term? And to what extent can short-lived secondary forests in dynamic agricultural landscapes contribute to the conservation of a high diversity of tree species? They randomly selected 45 secondary forest plots ranging from two to 32 years of age in which they counted more than 52,000 trees, palms and lianas. To the authors' knowledge, this was the first metacommunity study of its kind ever conducted in the tropics.

In the study plots, researchers found 324 tree and shrub species, about 55 percent of Agua Salud's suite of approximately 600 tree species. They estimated relative reproductive size thresholds and determined that in forests between 18 and 34 years of age, 51 percent (137 of 268 species) reached reproductive size. In forests between two and seven years of age, the figure fell to 36 percent (79 of 220 species). Importantly, these included few large-canopy species, slow-growing shade-tolerant understory species and species that depend on forest-dependent animals for seed dispersal.

If left undisturbed, secondary forests may regain levels of tree diversity similar to those of mature forestsbut only when the surrounding landscape includes natural seed sources like protected parkland, patches of old forest and remnant trees as it did in this case. The research underscores the importance of protecting old forests to maintain the tree diversity for which the tropics are famous.

"In the long term, we might see a distinct shift in the functional composition of human-altered landscapes," said van Breugel. "This kind of landscape becomes more and more dominated by a small group of species with specific traits like the ability to survive grazing and fire, high fecundity, good dispersal and the ability to grow to a reproductive age in a short period of time. On the other hand, many shade-tolerant trees are poorly dispersed, grow slowly and depend on forest-bound species for pollination and dispersal. Their conservation will depend on our ability to protect large areas of old-growth forests."


'/>"/>

Contact: Sean Mattson
mattsons@si.edu
202-633-4700 x8290
Smithsonian Tropical Research Institute
Source:Eurekalert  

Related biology news :

1. LSUHSC research finds inflammation linked to obesity in adults may be protective in young children
2. Connections in the brains of young children strengthen during sleep, CU-Boulder study finds
3. European young investigators network for Usher syndrome awarded E-Rare collab project
4. Tracking young salmons first moves in the ocean
5. Earliest marker for autism found in young infants
6. 23 researchers join network of EMBO Young Investigators
7. Diets low in polyunsaturated fatty acids may be a problem for youngsters
8. Young adults with autism found to have difficulty transitioning into employment
9. 1 pill can kill: Effects of unintentional opioid exposure in young children
10. Vigorous physical activity linked to lower incidence of obesity in young African-American women
11. Soft drinks and behavioral problems in young children
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Young tropical forests contribute little to biodiversity conservation
(Date:2/26/2017)... , Feb. 25, 2017  Securus Technologies, ... technology solutions for public safety, investigation, corrections and ... Recidivism and Reentry. "Too often, too ... prisons and county jails are trying to tackle ... inmates and friends and family members. While significant steps ...
(Date:2/21/2017)... , February 21, 2017 ... 70 Millionen US-Dollar wachsen. Nach einem Gespräch mit mehr als ... einige Hindernisse zu überwinden gilt, um diese Prognose zu ... ... anderem die Mobilisierung der finanziellen Mittel für die Biobank, ...
(Date:2/13/2017)... -- Former 9/11 Commission border counsel and Special Counsel ... of Identity Strategy Partners, LLP, today releases the ... Order: Protecting the Nation From Foreign Terrorist Entry Into ... President Trump,s ,Travel Ban, Executive Order gains more notoriety ... travel ban, it is important that our national discourse ...
Breaking Biology News(10 mins):
(Date:3/29/2017)... March 29, 2017  Halozyme Therapeutics, Inc. (NASDAQ: ... drug-delivery therapies, today announced that an Oncologic Drug ... Administration voted 11 to 0 that the benefit/risk ... was favorable for patients in the proposed indications ... chronic lymphocytic leukemia. The FDA action date is ...
(Date:3/29/2017)... ... March 29, 2017 , ... Bactana Animal Health, a company developing natural ... supply through enhancement of the gut microbiota, today announced the closing of its first ... New York-based Sustainable Income Capital Management, LLC and a number of private investors. The ...
(Date:3/29/2017)... -  GeneNews Limited (TSX:GEN) ("GeneNews" or the "Company") announced ... stratification test for breast cancer, via its Virginia ... incorporates a blood-based biomarker test with a sophisticated algorithm to ... cancer.   ... BreastSentry measures the fasting plasma levels of two biomarkers ...
(Date:3/28/2017)... (PRWEB) , ... March 28, 2017 , ... ... NetDimensions Learning to replace paper-based processes and enhance training plan management for consistent ... very pleased to partner with the SHL Group to help improve and streamline ...
Breaking Biology Technology: