Publications by authors named "Onrizal"

The Tapanuli Orangutan (Pongo tapanuliensis) is the most threatened great ape species in the world. It is restricted to an area of about 1,000 km2 of upland forest where fewer than 800 animals survive in three declining subpopulations. Through a historical ecology approach involving analysis of newspaper, journals, books and museum records from the early 1800s to 2009, we demonstrate that historically Pongo tapanuliensis inhabited a much larger area, and occurred across a much wider range of habitat types and at lower elevations than now.

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Article Synopsis
  • Understanding the biogeographic affinities of tropical forests helps explain regional differences in their structure, diversity, and responses to global changes.
  • The study classifies the world's tropical forests into five main floristic regions based on their phylogenetic relationships: Indo-Pacific, Subtropical, African, American, and Dry forests.
  • Findings challenge the traditional division of tropical forests and suggest a connection between northern-hemisphere Subtropical forests in Asia and America, as well as the existence of a global dry forest region.
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The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼ 40,000 and ∼ 53,000, i.e.

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Background: Mangrove forests are ecologically important but globally threatened intertidal plant communities. Effective mangrove conservation requires the determination of species identity, management units, and genetic structure. Here, we investigate the genetic distinctiveness and genetic structure of an iconic but yet taxonomically confusing species complex Rhizophora mucronata and R.

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