AUG 03, 2020 10:02 AM PDT

What the heck are biocrusts and why are they so important?

Have you ever heard of biocrusts? No, it’s not a new kind of pizza crust. Biocrusts refer to a group of tiny desert organisms (like mosses, lichens, cyanobacteria, and fungi) that live on the surface of dryland soils. While they’re so small you might not even notice them, new research published in Global Change Biology, suggests they play a very important role for our planet.

In a collaboration of researchers from UNSW Sydney, the United States, Spain, Germany, Mexico and China, the report details a comprehensive meta-analysis of the largest global database on the effects of biocrusts on water movement, storage and erosion in dryland soils.

Lead author Professor David Eldridge from UNSW Science comments, “Biocrusts are critically important because they fix large amounts of nitrogen and carbon, stabilize surface soils, and provide a home for soil organisms. But we still have a poor understanding of just how biocrusts influence hydrological cycles in global drylands.

"Accounting for biocrusts and their hydrological impacts can give us a more accurate picture of the impacts of climate change on dryland ecosystems and improve our capacity to manage those effects," Eldridge said.

Drylands are the most expansive biome covering land on Earth (they cover almost half of Earth's land surface and support almost 40% of the global human population) and biocrusts are often the most prevalent surface covering on dryland soils, so you can understand why it’s important to understand these little creatures. Yet, as co-author Dr. Samantha Travers explains, "The global literature on biocrust effects on hydrology has often been conflicting, preventing us from making broadscale recommendations on how to manage them to manage water.”

Photo: Pixabay

From their analysis, the researchers concluded that the presence of biocrusts increase water storage in the uppermost layers of the soil and reduce water erosion by an average of 68%. This was the general finding, they explain, despite the influence that soil disturbance and biocrust type had on water storage.

"This upper layer is where most of the nutrients and microbes are found -- it is a critical zone for plant production and stability in dryland soils," Eldridge said. "More water in the upper layers means greater productivity and stability."

"Cyanobacteria in the crusts secrete organic gels and polysaccharides that help to bind small soil particles into stable surfaces. Mosses in the crusts also trapped water and sediment on the soil surface, preventing the removal of soil particles," Dr. Travers said.

This field is emerging as evermore crucial because of the implications that it has for the millions of people, livestock, and wildlife that live in drylands. "The results of this work will be incorporated into global water balance and soil loss models so that managers and governments have a better understanding of the implications of losing biocrusts on the world's dwindling water supplies," commented Eldridge.

Sources: Global Change Biology, Science Daily

About the Author
  • Kathryn is a curious world-traveller interested in the intersection between nature, culture, history, and people. She has worked for environmental education non-profits and is a Spanish/English interpreter.
You May Also Like
JUN 14, 2020
Plants & Animals
Conservationists Begin Tracking Red Pandas with GPS Satellites
JUN 14, 2020
Conservationists Begin Tracking Red Pandas with GPS Satellites
The red panda (Ailurus fulgens) is one of several animals recognized as an endangered species on the International Union ...
JUN 18, 2020
Neuroscience
How Climate Change Worsened Zika Virus Defects
JUN 18, 2020
How Climate Change Worsened Zika Virus Defects
Image: Pixabay   In 2015 a massive outbreak of the Zika virus started in Brazil and spread across 33 countries. The ...
JUN 30, 2020
Plants & Animals
Consequences of Sixth Mass Extinction Threaten Humanity
JUN 30, 2020
Consequences of Sixth Mass Extinction Threaten Humanity
Many scientists have taken note of the rapid decline many of the world species, and several have declared that Earth's s ...
JUL 17, 2020
Microbiology
Metal-Eating Microbes Are Discovered
JUL 17, 2020
Metal-Eating Microbes Are Discovered
Researchers at Caltech have serendipitously found microbes that consume manganese for energy.
SEP 11, 2020
Earth & The Environment
Almost all forest fires are caused by humans, new study reports
SEP 11, 2020
Almost all forest fires are caused by humans, new study reports
New research published in the journal Fire reports that 97% of wildfires in the US that threaten homes are started by hu ...
SEP 15, 2020
Earth & The Environment
Mapping the footprints of storm surges
SEP 15, 2020
Mapping the footprints of storm surges
A study published in AGU's Journal of Geophysical Research: Oceans highlights the need for improving our u ...
Loading Comments...