Jul 18 2017
Globally, loss of biodiversity is caused due to climate change. Yet, innovative research published in Science Advances has reported that the impact of climate change on ecosystems with greater biodiversity may be less.
Experimental meadow plots with heating lamps. CREDIT: Jacob Miller.
An international team of Researchers has discovered that when meadows were experimentally warmed, the distinctive nematode worms in the soil were restricted to monocultures. In contrast, in the case of meadows comprising disparate herbaceous plant species, the opposite was observed.
June 2017 was recorded as the hottest ever June in various parts of the world. The year 2016 was the hottest year in the modern temperature record. Earth gets constantly heated up, which presents direct risks, such as drastic weather happenings and increase in global sea-level rise, to humans. However, Researchers worry that this might even have an indirect impact on the well-being of individuals through changes in biodiversity.
The diversified forms of life, such as, microorganisms, animals and plants, form the basis of various services, for example food or clean drinking water, that ecosystems offer. At present, the question faced by Ecologists is as follows: what is the impact of the increase in global temperatures on biodiversity? More species, less species or no change?
A group of Ecologists from the German Centre for Integrative Biodiversity Research (iDiv), Leipzig University, and the University of Minnesota have discovered that increase in temperatures may increase as well as decrease biodiversity, and that the course of the effect corresponds to the extent of biodiversity that primarily existed. In a long-duration field experiment carried out at Cedar Creek, Minnesota, the research team established over 30 disparate meadow plots, where certain plots had just one plant species, that is, monocultures. Some of the plots had nearly 16 disparate plant species.
Subsequently, the Researchers used heating lamps to warm the meadows to about 3 °C greater than the surrounding environment. Then, the research team recorded the impact of the warming on nematodes, that is, tiny worms seen abundantly in the soil, where many disparate species of the worm exist. Nematodes have vital roles for various ecosystem functions; for instance, they assist in transforming the soil highly fertile, which is highly significant for plant production.
When the monoculture plots were warmed, the Researchers noted that the diversity of nematodes was considerably reduced. In contrast, upon warming the plots using an increased number of disparate plant species, the nematode species number increased. Dr Madhav P. Thakur, a Postdoctoral Researcher at the iDiv research centre and the Leipzig University as well as the Lead Author of the study stated that, “The story is simple; you need biodiversity to conserve biodiversity in a warmer world.”
However, the story does not end here as the research team also outlines the constraints of biodiversity in recovering biodiversity in a hotter world. Even though they were able to observe a higher number of nematode species in the warmed plots that had higher plant diversity, the nematode species were very closely related, that is, they were more similar to one another. “The reason was that these species had all been selected for a common characteristic, namely tolerance to a warmer environment,” explained Thakur.
This increase in similarity can have implications for how well biological communities can respond to future environmental changes, potentially limiting the ‘insurance’ effect inherent in a higher numbers of species.
Dr Jane Cowles, a Postdoctoral Researcher, the University of Minnesota and a Co-Author of the study
To delineate the impact of this on the stability of ecosystems on Earth, the Authors say that further research is mandatory.
The monoculture meadow developed for the sake of conducting this experiment was similar to meadows seen in extensively managed agricultural land. Hence, the new outcomes of this study support conservationists who recommend preserving species-rich ecosystems and farmland to conserve biodiversity, and consequently human well-being, in a hotter world. This might assist in preventing negative impact of climatic changes, though possibly with certain restrictions.