There is something called ‘underground climate change’, and it is worrying scientists and engineers involved with aspects of urban planning as it could adversely affect the durability of structures and infrastructures in cities.
Underground climate change is explained as the impact due to rising subsurface temperatures because of human activity like basement parking, tunnel roads, subways, and underground rail, among others. These constantly emit heat which is trapped, affecting the soil by making it expand or contract. Researchers from Northwestern University in Evanston, Illinois, have for the first time linked underground climate change to shifting ground beneath urban areas.
From experiments based on simulations, they found that as the ground heats up, it also deforms, causing building foundations and the surrounding ground to move due to expansions and contractions and even cracks. This can ultimately affect structures’ long-term operational performance and durability. But they are quick to point out that this does not mean that the structures would collapse, just that their service life and servicing/maintenance itself could pose a challenge if the underground climate change is not curtailed.
Although this is the first time that we are coming across something called underground climate change, it also offers a potential opportunity. The waste heat trapped underground due to underground transportation, basement parking lots and the like, can be recycled as an untapped thermal energy source. The researchers are looking at strategies for adopting geothermal technologies to harvest the underground heat to enable its mitigation. They also suggest thermal insulations to building foundations to cut the amount of heat escaping underground.
It's root of all matter for plants
There’s a new finding in plant studies that can help plant breeders. In contrast to the earlier understanding that plant shoots controlled the growth process, new research has found that it is in fact the roots of the plant which control the entire process without the shoots even playing a role.
Agricultural scientists were of the understanding that plant shoots played the role of the long-distance transmitter signalling to the roots in what manner they should alter the growth process.
However, researchers from the Institute of Agricultural and Nutritional Sciences at Martin Luther University Halle-Wittenberg (MLU), Leibniz Institute of Plant Biochemistry (IPB), ETH Zurich, and Max Planck Institute for Plant Breeding Research in Cologne conducted an experiment that turned the tables on the earlier understanding.
They cut off the plant shoots to allow the roots to grow. They found that the roots were not affected by the plant shoots being cut and continued to grow, even at elevated temperatures the same manner as plants with the shoots intact. The researchers found that the higher temperature stimulated cell division and the roots became significantly longer. The researchers also experimented with mutant plants in which the shoots could not detect or respond to higher soil temperatures to affect the growth. But here too they found that the roots were able to react to the heat in the soil, although the shoot did nothing.
This has convincingly proved to scientists that plant roots had their own ‘thermometers’ to measure temperatures in the soil and adjust their growth accordingly without taking any signals from the plant shoots. The researchers say this finding makes root growth increasingly important for breeding. Understanding the molecular basis for temperature-dependent root growth could help effectively equip plants against drought stress and achieve stable yields in the long term.