Terraforming: load cells help create a landscape from scratch
The recent volcanic eruption on the island of La Palma in the Canaries is a vivid and powerful reminder of the power of nature to sweep aside all in its path, leaving behind a barren landscape devoid of organic life. History has also shown us that over time, that same volcanic rock will form the basis for a whole new landscape and ecosystem.
Terraforming in Arizona
An amazing experiment has been running for several years to discover just how a barren landscape after wildfires, volcanic eruptions or large scale mining would be colonised by microbes and plants. This process is known as terraforming, and is the subject of a major scientific experiment by the University of Arizona.
The Landscape Evolution Observatory, or LEO, is a set of three artificial hill slopes nestling under a giant biome of glass. According to a recent press release:
“Researchers from UArizona, Lawrence Berkeley National Laboratory and California Lutheran University will establish a complete ecosystem – with plants, artificial rain and sophisticated monitoring technology – on the large artificial hillslopes at the Landscape Evolution Observatory, or LEO, located inside UArizona’s Biosphere 2.”
Landscape monitoring built in
The construction of artificial slopes allowed scientists to literally ended monitoring and measurement into the experiment from
the very start:
“Each (slope) is equipped with 1,900 sensors and sampling devices that enable scientists to monitor water, carbon and energy cycling processes and the physical and chemical evolution of the landscape at small and large scales.”
An article in Nature gives more details:
“Buried in the soil of each hillslope are more than 1,200 sensors measuring soil water content, soil water potential, soil temperature, soil carbon dioxide concentration, heat flux, electrical resistivity, and hydrostatic water pressure. There are also more than 630 sampling points, allowing physicochemical analyses of water and gases within the soil.
Outside the hillslopes, water storage in the soil is accounted for through 10 large load cells for each hillslope whereas discharge is monitored by a combination of tipping buckets and electromagnetic flowmeters. … Precipitation is not measured directly but precisely controlled by the irrigation system.”
An ecosystem from scratch
According to Scott Saleska, a professor in the Department of Ecology and Evolutionary Biology who took over as LEO’s director of science earlier this year, LEO will:
“Allow us to answer a question central to ecology: Can we predict what is going to happen when we build up an ecosystem from scratch? LEO allows us to literally watch life’s complexity build up from ground zero.”
Where does the rain go?
Key to this investigation is the way that water moves through a landscape, and answer the fundamental question of how much and how mountain rainfall percolates through to ground level. LEO’s hillsides are created with a steel substructure that creates what is essentially a giant seed tray, containing crushed basalt rock from an Arizona volcano.
Watered from above to imitate natural precipitation, the movement of water down through the slope is measured by 10 load cells. By weighing the amount of water used in simulated rainfall, the team can track how much runs off, or is lost through evaporation and plant life transpiration.
As the Nature article explains:
“Relative water storage was computed by adding the weights from the 10 load cells (only when all of the measures passed the quality control) and then subtract the total mass weight from the lowest water storage content.”
Water is pumped from a local well into seven storage tanks below the slopes, which can deliver purified water to any of the three slopes as required.
More load cells details
The load cells used in the LEO structure can monitor changes in the total mass of the system equivalent to just 1cm of precipitation (0.05% full-scale repeatability with a range of 1000 – 150 tons). There’s a closeup image of the load cell in position at this site.
“Temporal changes in water storage within the entire landscape are monitored via 10 load cells installed under the only load-bearing points connecting the main hillslope with the supporting structure. … These loads cells were installed at a nexus point between the primary vertical supports and the lateral beams forming the perimeter of the steel trays.”
Need load cells for monitoring your scientific experiments?
Contact us. We have provided reliable, cost-effective load cells for a whole range of research at academic institutions and commercial organisations. Contact us to discuss your requirements:
