Scientists have been struggling to explain how tropical woods can go to; maintains the spectacular diversity of trees without capturing some species over or if many other species are infected; die.
The answer, which researchers say, lies in the soil found near individual trees, where "natural enemies" of trees are living. These enemies, including fungi and arthropods, attack and attack. Many of the seeds and seabirds were killed close to hospitality, and preventing the conversion of trees of the same species locally.
As well as playing play an important part in the & # 39; tropical woods are dynamic in silk. Seeds from individual trees transported distance – often with predators, mammals or birds have to be based on the fact that fungi and creatures in the new sector target different species. This restriction on tree fastening is close to adult trees that create a long-term, long-term impact that affects; leaving rare species and preventing ordinary ones, which researchers say.
Stopping down the theory; The researchers have shown that such interaction with enemies is important enough to maintain the fascinating diversity of tropical forests. The results of the survey are released this week National Academy of Sciences Affairs (ThePNAS).
"In many North American forests, trees will compete for a place and some of them who can afford to support others," said Taal Levi, an eco Oregon State University advisor and main author of the study. "Douglas-firs are the best-growing species after a fire. Hemlock is successful in the appearance and its growth is well under a toy. Some species doing good at raising.
"But in the tropics, there is a similar competitiveness of every tree species. There are plenty of species, but very few individuals of each species. There should be a chance to & # 39; tightening up. But a machine needs to keep one species from becoming common, getting stronger. And those natural enemies that are especially the host. "
Egbert Leigh, of the Smithsonian Tropical Research Institute, said the best of tropical forest diversity in one statement: "As a square kilogram (of wood) in Borneo or Amazonia can not be & # 39 ; including so many trees as 4.2 million kilometers of teashed zone woodland in Europe, North America together and Asia together? "
Levi said tropical forests with up to 1,000 different tree species are living in the same general range. The idea of natural enemies does not limit the recruitment of new youth trees, he said, and in fact was built almost fifty years ago by two scientists in the name & 39; on the Janzen-Connell concept.
Although Janzen-Connell should affect one species from taking over, they do not. explain or explain how to maintain a thousand tree species together. Indeed, previous researchers suggested that they did not. The effects of Janzen-Connell can only maintain very few species, so they were vitally important in maintaining tropical woodland diversity in general.
Instead, Lebhi and his colleagues from the University of Florida, the State of Oregon, and the University of James Cook of Australia say that this close relationship between trees and their natural enemies is a major place for tropical woodland diversity. They were discovered if fungi, arthropod and other natural enemies produce small zones around trees where a single tree can not be established of the same species, the upper levels of Tree diversity maintained in tropical forests is maintained without long termination.
"Silk shawls around adult trees and some get rid of the loop and get out, and employing in other areas to Are hostile-based special enemies based in the new place, "said Levi. "That's why it's important to sustain the biodiversity of birds and mammals in these woods, or eventually the decline will be a decline – especially in hunting areas. "
Levi is in the Oregon State Fisheries and Wildlife Department, at the College of Agricultural Sciences.
Interactive & cryptic & # 39; causing biodiversity decline near the outskirts of woodland
Taal Levi al al., "Multiple tropical tropical forests can be held because of their enemies," PNAS (2018). www.pnas.org/cgi/doi/10.1073/pnas.1813211116