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"Megaherbivores act as the 'gardeners' of humid tropicalforests: They are vital to forest regeneration and maintain itsstructure and biodiversity," as was explained by AhimsaCampos-Arceiz, the lead author of the study that was published inthe 'Biotropica' journal and researcher at the School of Geographyof the University of Nottingham in Malaysia. In these forests in East Asia, the large diversity of plant speciesmeans that there is not enough space for all the trees to germinateand grow. As well as the scarce light, seed dispersion is made morecomplicated by the lack of wind due to the trees that are up to 90metres high. Plant life is then limited to seeds dispersed by thoseanimals that eat pulp. They either scatter seeds by dropping theirfood, regurgitating it or by defecating later on. In the case of large seeds, "plants need a large animalcapable of eating, transporting and defecating the seeds in goodconditions," as outlined by Luis Santamaría, co-authorand researcher at the Mediterranean Institute for Advanced Studies(IMEDEA) of Spain's CSIC Scientific Research Agency. This is whereelephants and rhinoceroses come into play because they can scatterlarge quantities of seeds thanks to the fact that they slowlydigest very little of their food. However, habitat loss, poaching, and the conflict between elephantand man has caused a 95% loss in Asian elephant ( Elephas maximus ) historical distribution range and has left the rhinoceros just astep away from extinction: there are less than 50 Java rhinoceroses(Rhinoceros sondaicus) and 200 Sumatra rhinoceroses ( Dicerorhinus sumatrensis ). According to the red list of the International Union forConservation of Nature (IUCN), elephants are in 'danger ofextinction' and the two rhinoceros species are 'criticallyendangered'. Asian tapirs are no elephants In light of the situation, the research team evaluated theseed-dispersing capacity of another large herbivore weighing 300kg. For cultural reasons it is not hunted and has a similardigestive system to that of elephants and rhinoceroses: the Asiantapir ( Tapirus indicus ). The study allowed researchers to analyze the effect of dispersionby tapirs on the seed survival of nine different plants. Thisincluded some large plant species such as the mango tree anddurian, as well as other smaller species like the 'elephant apple'( Dillenia indica ). Among other outcomes, the results show that tapirs defecated 8% ofthe tamarind seeds ingested (none of which germinated) compared toelephants, who defecated 75% of the 2,390 ingested seeds (65% ofwhich germinated). "The Asian tapirs spit, chew or digest the majority of largeseeds. This either destroys them or leaves them in the same place.As a result, they are not good dispersers for plants with largefruits and seeds," confirms Campos-Arceiz. In this sense,"given the role that they play they belong to a differentgroup to elephants and rhinoceroses." Stopping illegal hunting is the priority "If these megaherbivores disappear from the ecosystem, theircontribution to ecological processes will too be lost and the pathof the ecosystem will change irreversibly," explains the leadauthor, who goes on to state that "the most probableconsequences are the change in the structure of the undergrowth andthe forest and the loss of certain species." Elephants andrhinoceroses play a unique ecological role that cannot be replacedby other species. Without large herbivores, new large seed plants will always grow inclose proximity to the mother plant and are therefore "unableto colonise available space in other forest areas," warns theIMEDEA researcher. In this respect, those species that depend on large animals willbecome increasingly rare whereas those that depend on the wind andsmaller, abundant animals will increase in terms of density anddominance. Campos-Arceiz asserts that "at the end of the day,the composition and structure of the forest changes and ends upbecoming less complex on a structural and functional level: thistranslates as a loss of biodiversity." To avoid such a scenario, researchers suggest that megafauna shouldbe protected and in some cases megaherbivores should bereintroduced into areas from where they had previously disappeared."In the south-east of Asia, the priority is to stop illegalhunting and mitigate the impact of habitat loss," indicatesthe expert, criticising the "absurd" motivation to killin order to sell their horns and tusks for traditional medicine("with no therapeutic benefits") or to make ornamentalproducts. This also highlights the need to combat illegal trade ina "much more determined way.". The e-commerce company in China offers quality products such as China Hydraulic Pumps And Motors , China Kayaba Pumps, and more. For more , please visit Sauer Pumps today!
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