Research clarifies potential drivers of toxic elements along elevation gradients in terrestrial ecosystems

The accumulation of toxic elements poses a significant threat to terrestrial ecosystems, and the patterns and influencing factors of this accumulation are complex. However, along with the underlying drivers, the elevation patterns of toxic elements in mountain ecosystems are largely unexplored.

In a study published in Ecological Indicators, researchers at Xishuangbanna Tropical Botanical Garden (XTBG) at the Chinese Academy of Sciences provided clear insight into the notion that changes in elevation gradients driven by changes in climate and vegetation play an important role in altering the patterns of toxic elements in the Montan Ecole body.

The researchers conducted an in-depth literature review to comprehensively analyze previous studies, which aimed to identify distribution patterns and determinants of toxic elements across different elevation gradients.

The researchers determined that atmospheric deposition plays a pivotal role in the accumulation of toxic elements along terrestrial altitude gradients. Aerosols, particulate matter, and microtoxic substances are transported through the atmosphere from proximity or distant point sources such as industrial chimneys. In particular, air deposition showed seasonal variations, with increased deposition rates during summer and winter.

Furthermore, the researchers found that the accumulation patterns of individual toxic components exhibited variability. Certain elements showed an increase in concentration along the elevation gradient, while others showed a decrease. Approximately 10% of the elements presented a hump-shaped distribution, while 20% lacked an identifiable pattern.

The toxic elements of long wind-mediated transport can settle on the leaves and then accumulate in the soil through mechanisms such as through falling and debris decomposition. Climate change along the elevation gradient has established microclimates that enhance the cold trapping of these toxic elements in the atmosphere.

Furthermore, it has been revealed that air deposition, human activity, and precipitation are the main factors affecting the accumulation of toxic components. Seasonal variations, especially during summer and winter, were also adjusted for the rate of deposition of toxic elements (both wet and dry). Researchers noted that toxic factors pose serious risks to terrestrial biota and can have a significant impact on garbage decomposition and nutrition cycling.

“To protect biodiversity, further research into how toxic elements affect ecosystem functioning and corresponding conservation measures are needed,” said Xu Guorui of XTBG.