New Delhi:Changing patterns of rainfall due to climate change could reduce the ability of soil to absorb water in many parts of the world, shows a new study. This can have serious implications on groundwater supplies, food production, storm-water runoff as well as biodiversity and ecosystems.
The observations were made in a study led by US based Rutgers University which was published in journal Science Advances.
"Since rainfall patterns and other environmental conditions are shifting globally as a result of climate change, our results suggest that how water interacts with soil could change appreciably in many parts of the world, and do so fairly rapidly," said co-author Daniel Gimenez, a soil scientist at Rutgers University.
The research was conducted over a period of 25 years in Kansas and involved irrigation of prairie soil, associated with temperate grasslands with sprinklers. Scientists found that a 35% increase in rainfall led to a 21-33% reduction in water infiltration rates in soil and only a small increase in water retention.
The findings are supported by previous studies which show that water infiltration to soil can change over one to two decades with increased rainfall, and climate change is expected to boost rainfall in many areas of the world.
"We propose that the direction, magnitude and rate of the changes should be measured and incorporated into predictions of ecosystem responses to climate change," stated the researchers in the study. This can affect rain-fed agriculture in several parts of the world.
Whether rain water will penetrate the soil or run off determines how much water will be available for plants.
The study comes a year after a research published in peer journal Nature, which was also co-authored by Gimenez, showed that regional increases in precipitation due to climate change may lead to less water penetration, more runoff and erosion, and greater risk of flash flooding.
The biggest changes were linked to shifts in large pores in the soil. Large pores capture water that plants and micro-organisms can use, and that contributes to enhanced biological activity and nutrient cycling in soil and decreases soil losses through erosion.
However, with increase in rainfall, plant had thicker roots that could clog larger pores and there were less intense cycles of soil expansion when water was added or contraction when water was removed, the study said.
Researchers highlighted that the next step is to investigate the mechanisms driving the observed changes in order to extrapolate the findings to other regions of the world and incorporate them into predictions of how ecosystems will respond to climate change.