October 2019: Climate change changing rainfall patterns may show negative effects on soil’s ability to retain water. Reduced soil resilience increases risks of groundwater depletion, flash floods, and release of carbon stored in soil.
Information
A recent study found that climate change is adversely impacting soil’s ability to retain water, causing knock-on effects for groundwater supplies, food production and security, storm water run-off, biodiversity, and ecosystems. Rainfall patterns and environmental conditions are shifting on a global level due to climate change and are gradually re-shaping how water interacts with soil. The study argues that a 35% increase in rainfall could lead to a 21-33% reduction in water infiltration rates, thus, causing water to erode top soil, releasing additional carbon from soil and depleting soil nutrients. Extreme floods followed by extreme droughts are changing the soil structures and increasingly raise the risk for soil degradation and desertification, negatively impacting soil health.
Implications & Opportunities
The changing composition of soil structures and its reduced ability to retain water may lead to decreasing groundwater supplies, increased run-offs and erosion, as well as a greater risk of flash flooding, negatively impacting communities. Against this background, the paper proposes new policies for farmers, designed to improve soil management practices. These policies include financial aid, tax exemptions, technical assistance or grants for farmers, incentivising the planting of cover crops, diversifying crop rotations and reducing tillage to increase soil resilience. In addition, soils could be enriched introducing nutrient rich manufactured soils.
Limitations
The paper highlights that all policy recommendation are at a global-level and, therefore, should be tailored to appropriately address the needs of local farmers.
Sources
Caplan, J. S., Giménez, D., Hirmas, D. R., Brunsell, N. A., Blair, J. M., & Knapp, A. K. (2019). Decadal-scale shifts in soil hydraulic properties as induced by altered precipitation. Science Advances, 5(9), eaau6635. doi:10.1126/sciadv.aau6635
India Today (2019). Climate Change May Reduce the Ability of Soil to Absorb Water. Retrieved from https://www.indiatoday.in/education-today/gk-current-affairs/story/climate-change-may-reduce-the-ability-of-soil-to-absorb-water-1602232-2019-09-23
