At 2.77 billion, the Pacific coral reef microbiome is astonishingly diverse

A new study by French scientists has found that the diversity of the Pacific coral reef microbiome, the microbiome that helps drive and sustain coral reef productivity and biodiversity, could reach the current estimate of the Earth’s total microbial diversity. The study was published June 1 in Nature Communications.

The findings, which use data collected during the two-year voyage of the Tara Pacific Exploration Project, represent the largest survey of coral reef microbiome diversity to date, suggesting that global microbial populations may be vastly underestimated.

Coral reefs are among the most diverse ecosystems on Earth, supporting 30% of marine biodiversity, including millions of multicellular organisms and associated microorganisms. These microbes are powerful indicators of coral reef health, but the extent of coral reef biodiversity has not been fully explored at the marine level. Moreover, there are widespread concerns about the future of coral reefs due to the decline in coral reef cover brought about by climate change.

Pierre Galand and colleagues from the Sorbonne University’s Geochemical Benthic Environmental Ecology Laboratory collected a total of 5,392 samples from three reef species (plate-leaved kiloporous coral, clumped coastal coral, multi-curved cup-shaped coral), two fish species (cross-banded stickleback and horned sickle), and plankton from 99 different reef groups in 32 island systems in the Pacific between 2016 and 2018. The samples were sequenced to determine the microbial composition of coral reefs and mapped to document geographic distribution. They also measured the temperature, salinity, and other environmental characteristics of the water at each sampling point.

According to Galand, the sample included 2.87 billion genetic sequences, which is about 25 percent more than the 2.2 billion previously reported by the Earth Microbiome Project, a global microbiome diversity mapping project. Overall, plankton exhibited the highest microbiome diversity. Plate-leaved thousand-hole corals have the highest microbiome diversity among coral species, and the microbiome diversity of horned sickle is higher than that of cross-banded stickleback. This is inconsistent with the previously expected pattern of higher coral microbial diversity in the western Pacific, which hosts more coral species than the eastern Pacific. There was also no significant correlation between sea temperature and microbial diversity.

In another paper, also published in the journal, Alice Rouan, Eric Gilson and colleagues of the University of the Côte d’Azur investigated the relationship between water temperature changes and telomere length, an environmentally sensitive marker of health and aging, between two types of reef-building corals. They found that seasonal temperature changes affected telomere length in short-lived and pressure-sensitive stony corals, while longer-lived and robust stony corals were more susceptible to perverse heat waves and cold periods than seasonal variations. This suggests that telomeres in some corals may respond differently to the effects of climate change.

The Tara Pacific Expedition is a multidisciplinary project that explores thousands of coral reef biodiversity across the Pacific, involving more than 100 scientists from 23 institutions in 8 countries. The sailing ship Tara embarked on a two-and-a-half-year voyage, collecting samples from more than 30 island systems. The findings from this expedition were published in a collection of 8 papers in several Springer Nature journals. Together, these articles bring new insights into coral reef health and biodiversity across the Pacific. (Source: Feng Weiwei, China Science News)

Image source: Pixabay

Related paper information:

Source link

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button