If it gets even warmer in the tropics as a result of climate change, will this affect the plant species there? Apparently the opposite is true for most pineapple plants, as the Oldenburg biologist Lilian-Lee Müller discovered. The surprising result of her research concerns up to 3,000 species.
The global rise in temperature as a result of climate change does not affect all tropical plants equally: On the contrary, the seeds of pineapple plants germinate well and potentially even better with the predicted rise of three degrees Celsius for the tropics by 2100, as Müller found out. Today, the plant ecologist from the Institute of Biology and Environmental Sciences (IBU) presented her findings to the public for the first time at the annual conference of the Society for Ecology (GfÖ) in Göttingen.
The neotropical pineapple family, which includes around 3000 other species in addition to the pineapple, has no disadvantages due to climate change when it comes to seed germination, as Müller's laboratory experiment proves. A surprising result - even for the experts Prof Dr Dirk Albach and Prof Dr Gerhard Zotz from IBU: "We previously thought that climate change would have a particularly negative impact on tropical species. The climate here fluctuates little throughout the year and many species are specialised."
Müller studied 41 species of pineapple plants (Bromeliaceae) and observed how a total of 20,000 of their seeds developed at higher temperatures. "Seed germination is the first step in plant growth. Species are quickly out of the running if they don't germinate optimally - especially in the densely overgrown neotropical forests," says Müller. How diversity develops in the particularly species-rich tropics as a result of global warming is relevant for biodiversity worldwide.
For an average temperature increase of three degrees Celsius, as predicted by scientists for the tropics by the year 2100 in view of climate change, the following applies: the seeds of 93 per cent of the species studied germinate perfectly, and 85 per cent germinate even better. As climate change is expected to alter not only temperature but also precipitation, the researchers at IBU now want to investigate how the different availability of water affects seed germination.
In addition to the pineapple, the Bromeliaceae family also includes well-known houseplants such as the lancet rose and the flaming sword. In the neotropical forests of South America, the pineapple plants are not only relevant for biodiversity because of their species richness: small bodies of water form in their leaf funnels, which are used by numerous algae and plants as well as small animals such as poison dart frogs. Like many other pineapple plants, the species studied do not germinate and grow in the soil, but on other plants such as trees, on which their seeds are carried by the wind or animal faeces.
Lilian-Lee Müller is a PhD student in the research groups "Biodiversity and Evolution of Plants" and "Functional Ecology of Plants". Dr Eva Diehl is the press officer of the Society for Ecology and has summarised Müller's research findings on the occasion of the current annual conference in Göttingen.
