Climate change has a significant impact on all aspects of our existence. Food security is one of the most important and concerning. Changing weather patterns are affecting the global success of crops. The increase in extreme weather conditions, such as floods and droughts, has caused damage or, in some cases, even the loss of essential crops.
FoodNavigator reports on the impact of extreme weather conditions, such as tornadoes, hurricanes, and floods, among others. Olive oil, peanuts, SugarYou can also learn more about the following: Butter. Researchers have discovered that soil contains much more mercury than previously thought. This increase is also a result of climate change. Why are rising levels of mercury in soil a danger to food and crops?
What are the dangers of high mercury levels in soil?
The National Library of Medicine states that high levels of mercury in soil can have a detrimental effect on plant growth.
Mercury contamination from food grown on mercury-contaminated soil could affect human health.
A spokesperson for the World Health Organization said that exposure to mercury, even in small amounts, can cause health problems. It also poses a danger to a child's development in utero or early in life. It can have toxic effects on the immune, nervous and digestive systems as well as the lungs and kidneys.
How does climate change impact soil mercury levels?
The study published by ACS Environmental Science & Technology estimates that soil contains much more mercury than previously thought. It also predicts an increase in plant growth due to climate change.
Mercury is an environmental pollutant that persists in air, soil, and water. It accumulates in animals and plants. While metals like mercury naturally move into other elements, human activity appears to have altered the cycle. How? Researchers say human-caused climate change is increasing carbon dioxide levels, which promotes vegetation growth, and depositing more mercury in the soil as vegetation decomposes.
Previous studies of soil mercury concentrations were mainly based on regional and small-scale data. This new study led by Xuejun Liu and Maodian Wang, along with their collaborators, aimed to develop a global model that would be more accurate in assessing soil mercury levels.
The researchers compiled nearly 19,000 previously published soil mercury measurements, resulting in one of the largest databases ever created. This dataset was fed into an algorithm that uses machine learning to calculate global mercury distributions in both topsoil and subsoil.
This team found that the amount of mercury in the top 40 inches of soil (about a meter deep) is about 4.7 million tons. The 4.7 million ton figure is more than double some previous estimates, even though those previous studies considered deeper soil depths.
The researchers' models identified areas with dense plants, such as low latitudes in the tropics and permafrost. They also found high levels of soil mercury in areas with high human populations. In contrast, shrublands and grasslands with low soil mercury had low concentrations.
As temperatures rise around the world, vegetation is expected to grow faster. This would increase mercury concentrations in soil. The projected increase in mercury would also outpace any reductions proposed by the current global control system. This research, the team concluded, underscores the importance of stricter, long-term control of mercury emissions.
How to reduce mercury levels in soil?
Mercury, like other heavy metals, does not degrade in ecosystems. Therefore, remediation is only possible through immobilization or removal processes. These processes have already been implemented by environmental agencies around the world, but this study shows that more needs to be done to reduce public health risks and ensure crop success.
Source: Greening of vegetation induced by global warming could increase mercury levels in soil
Publication date: August 14, 2024
DOI: 10.1021/acs.est.4c01923
Authors: Wenzhe Guo, Maodian Liu, Qianru Zhang, Yidan Deng et al.
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