Plants and trees have long been known to extend their roots into the earth in search of nutrients and water. However, a new study has revealed that many plants develop a second, deeper layer of roots – often more than three feet underground – to access additional nourishment. This discovery, published in the journal Nature Communications, changes our understanding of how ecosystems respond to changing environmental conditions.

The research team, led by Mingzhen Lu from New York University’s Department of Environmental Studies, used data from the National Ecological Observatory Network (NEON) to examine rooting depth. By digging deeper than traditional ecological studies – up to 6.5 feet below the surface – they detected additional root patterns in diverse climate zones and ecosystem types.

The scientists’ work focused on three key questions: How do plants acquire resources? What strategies do they employ to adapt to environmental change? And what are the implications for carbon storage?

Their findings were striking: nearly 20 percent of the studied ecosystems had roots that peaked twice across depth – a phenomenon called “bimodality.” In these cases, plants developed a second, deeper layer of roots, often aligning with nutrient-rich soil layers. This suggests that plants have been growing in previously unknown ways to exploit additional sustenance.

The study’s lead author, Mingzhen Lu, observes that the current understanding of roots is “literally too shallow.” By not looking deep enough, we may have overlooked a natural carbon storage mechanism deep underground. The research opens up new avenues for inquiry into how bimodal rooting patterns impact the dynamics of nutrient flow, water cycling, and long-term soil carbon stock.

As scientists and policymakers look to manage ecosystems in a rapidly changing climate, they must consider these overlooked deep soil layers. The study concludes that plants may already be naturally mitigating climate change more actively than we’ve realized – we just need to dig deeper to fully understand their potential.

The Hidden Impact of Anoxic Pockets on Sandy Shores

Human activities have dramatically increased nitrogen inputs into coastal seas, leading to a significant amount of this human-derived nitrogen being removed by microorganisms in coastal sands through denitrification. However, research has shown that this process can also occur in oxygenated sands, and scientists from the Max Planck Institute for Marine Microbiology in Bremen, Germany, have now revealed how this happens.

The scientists used a method called microfluidic imaging to visualize the diverse and uneven distribution of microbes and the oxygen dynamics on extremely small scales. “Tens of thousands of microorganisms live on a single grain of sand,” explains Farooq Moin Jalaluddin from the Max Planck Institute for Marine Microbiology. The researchers could show that some microbes consume more oxygen than is resupplied by the surrounding pore water, creating anoxic pockets on the surface of the sand grains.

These anoxic microenvironments have so far been invisible to conventional techniques but have a dramatic effect: “Our estimates based on model simulations show that anaerobic denitrification in these anoxic pockets can account for up to one-third of the total denitrification in oxygenated sands,” says Jalaluddin.

The researchers calculated how relevant this newly researched form of nitrogen removal is on a global scale and found that it could account for up to one-third of total nitrogen loss in silicate shelf sands. Consequently, this denitrification is a substantial sink for anthropogenic nitrogen entering the oceans.

In conclusion, the hidden impact of anoxic pockets on sandy shores has been revealed by scientists, highlighting the importance of these microenvironments in removing nitrogen from coastal seas and emphasizing the need to consider them when assessing the overall nitrogen budget of our planet.

The article highlights a critical aspect of environmental degradation: the rising soil nitrous acid (HONO) emissions driven by climate change and fertilization, which accelerate global ozone pollution. A team of researchers from The Hong Kong Polytechnic University has examined global soil HONO emissions data from 1980 to 2016 and incorporated them into a chemistry-climate model. Their findings reveal that soil HONO emissions contribute significantly to the increase in the ozone mixing ratio in air, which has negative impacts on vegetation.

The researchers found that soil HONO emissions have increased from 9.4 Tg N in 1980 to 11.5 Tg N in 2016, with a 2.5% average annual rise in the global surface ozone mixing ratio. This increase may lead to overexposure of vegetation to ozone, affecting ecosystem balance and food crop production. Moreover, ozone damage reduces vegetation’s capacity to absorb carbon dioxide, further aggravating greenhouse gas emissions.

The study emphasizes that soil HONO emissions are influenced by nitrogen fertiliser usage and climate factors like soil temperature and water content. Emissions hotspots cluster in agricultural areas worldwide, with Asia being the largest emitter (37.2% of total).

Interestingly, regions with lower pollution levels are more affected by ozone formation due to higher volatile organic compound concentrations and lower nitrogen oxide levels. This implies that as global anthropogenic emissions decrease, the impact of soil HONO emissions on ozone levels may increase.

To mitigate this issue, Prof. Tao Wang recommends considering soil HONO emissions in strategies for reducing global air pollution. The research team developed a robust parameterisation scheme by integrating advanced modelling techniques and diverse datasets, which can facilitate more accurate assessments of ozone production caused by soil HONO emissions and their impact on vegetation.

Future studies should explore mitigation strategies to optimise fertiliser use while maintaining agricultural productivity, such as deep fertiliser placement and the use of nitrification inhibitors.