Ghosts of past pesticide use can haunt organic farms for decades
2021-03-03
(Press-News.org) Although the use of pesticides in agriculture is increasing, some farms have transitioned to organic practices and avoid applying them. But it's uncertain whether chemicals applied to land decades ago can continue to influence the soil's health after switching to organic management. Now, researchers reporting in ACS' Environmental Science & Technology have identified pesticide residues at 100 Swiss farms, including all the organic fields studied, with beneficial soil microbes' abundance negatively impacted by their occurrence.
Fungicides, herbicides and insecticides protect crops by repelling or destroying organisms that harm the plants. In contrast, organic agriculture management strategies avoid adding synthetic substances, instead relying on a presumably healthy existing soil ecosystem. However, some organic farms are operating on land treated with pesticides in the past. Yet, it's unclear whether pesticides have a long-lasting presence in organically managed fields and what the reverberations are to soil life, specifically microbes and beneficial soil fungi, years after their application. So, Judith Riedo, Thomas Bucheli, Florian Walder, Marcel van der Heijden and colleagues wanted to examine pesticide levels and their impact on soil health on farms managed with conventional versus organic practices, as well as on farms converted to organic methods.
The researchers measured surface soil characteristics and the concentrations of 46 regularly used pesticides and their breakdown products in samples taken from 100 fields that were managed with either conventional or organic practices. Surprisingly, the researchers found pesticide residues at all of the sites, including organic farms converted more than 20 years prior. Multiple herbicides and one fungicide remained in the surface soil after the conversion to organic practices; though the total number of synthetic chemicals and their concentrations decreased significantly the longer the fields were in organic management. According to the researchers, some of the pesticides alternatively could have contaminated the organic fields by traveling through the air, water or soil from nearby conventional fields. In addition, the team observed lower microbial abundance and decreased levels of a beneficial microbe when fields had higher numbers of pesticides in the fields, suggesting that the presence of these substances can decrease soil health. The researchers say future work should examine the synergistic effects of pesticide residues and other environmental stressors on soil health.
INFORMATION:
The authors acknowledge funding from Agroscope, Swiss Federal Office for the Environment, the Swiss National Science Foundation and the National Research Program 'Sustainable use of soil as a resource'.
The paper is freely available as an ACS AuthorChoice article here.
For more of the latest research news, register for our upcoming meeting, ACS Spring 2021. Journalists and public information officers are encouraged to apply for complimentary press registration by emailing us at newsroom@acs.org.
The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS' mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and its people. The Society is a global leader in providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a specialist in scientific information solutions (including SciFinder® and STN®), its CAS division powers global research, discovery and innovation. ACS' main offices are in Washington, D.C., and Columbus, Ohio.
To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.
Follow us: Twitter | Facebook
ELSE PRESS RELEASES FROM THIS DATE:
2021-03-03
In earlier days of the COVID-19 pandemic, before diagnostic testing was widely available, it was difficult for public health officials to keep track of the infection's spread, or predict where outbreaks were likely to occur. Attempts to get ahead of the virus are still complicated by the fact that people can be infected and spread the virus even without experiencing any symptoms themselves.
When studies emerged showing that a person testing positive for COVID-19 -- whether or not they were symptomatic -- shed the virus in their stool, "the sewer seemed like the 'happening' place to look for it," said Smruthi Karthikeyan, PhD, an environmental engineer and postdoctoral researcher at University of California ...
2021-03-03
Healthy human bodies are good at regulating: Our temperatures remain around 98.6 degrees Fahrenheit, no matter how hot or cold the temperature around us. The sugar levels in our blood remain fairly constant, even when we down a glass of juice. We keep the right amount of calcium in our bones and out of the rest of our bodies.
We couldn't survive without that regulation, called homeostasis. And when the systems break down, the results can cause illness or, sometimes, death.
In presentations at the American Association for the Advancement of Science's annual meeting, researchers argued that mathematics can help explain and predict those breakdowns, potentially offering new ways of treating the systems to prevent or fix them when things go wrong. The meeting ...
2021-03-03
Imagine seeing the world in muted shades -- gray sky, gray grass. Some people with color blindness see everything this way, though most can't see specific colors. Tinted glasses can help, but they can't be used to correct blurry vision. And dyed contact lenses currently in development for the condition are potentially harmful and unstable. Now, in ACS Nano, researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.
Some daily activities, such as determining if a banana is ripe, selecting matching clothes or stopping at a red light, can be difficult for those ...
2021-03-03
Land stores vast amounts of carbon, but a new study led by Cranfield University's Dr Alice Johnston suggests that how much of this carbon enters the atmosphere as temperatures rise depends on how far that land sits from the equator.
Ecosystems on land are made up of plants, soils, animals, and microbes - all growing, reproducing, dying, and breathing in a common currency; carbon. And how much of that carbon is breathed out (also known as ecosystem respiration) compared to how much is stored (through primary production) has impacts for climate change. ...
2021-03-03
Using the model organism Caenorhabditis elegans, researchers at the University of Cologne have developed an 'aging clock' that reads the biological age of an organism directly from its gene expression, the transcriptome. Bioinformatician David Meyer and geneticist Professor Dr Björn Schumacher, director of the Institute for Genome Stability in Aging and Disease at the CECAD Cluster of Excellence in Aging Research and the Center for Molecular Medicine Cologne (CMMC), describe their so-called BiT age (binarized transcriptomic aging clock) in the article 'BiT age: A transcriptome based aging clock near the theoretical limit of accuracy' in Aging Cell.
We are all familiar ...
2021-03-03
Alexandria, Va., USA -- The clinical picture of COVID-19 in various target organs has been extensively studied and described, but relatively little is known about the characteristics of oral cavity involvement. The study "Frequent and Persistent Salivary Gland Ectasia and Oral Disease After COVID-19" published in the Journal of Dental Research (JDR), investigated the presence and prevalence of oral manifestations in COVID-19 survivors.
Researchers at the Università Vita Salute San Raffaele, Milan, Italy, profiled the oral involvement in 122 COVID-19 survivors, hospitalized and followed up at a single referral visit after a median 104 days from ...
2021-03-03
Systemic fungal infections are much rarer than other illnesses, but they are potentially deadly, with limited options for treatment. In fact, fungi are becoming increasingly resistant to the few drugs that are available, and infections are growing more common. A cover story in Chemical & Engineering News, the weekly newsmagazine of the American Chemical Society, details how scientists are working to improve our antifungal arsenal.
At present, there are only four types of antifungal drugs approved by the U.S. Food and Drug Administration (FDA), and some infections are resistant to those drugs, making surgery ...
2021-03-03
Fields are covered with dandelions in spring, a very common plant with yellow gold flowers and toothed leaves. When they wither, the flowers turn into fluffy white seed heads that, like tiny parachutes, are scattered around by the wind. Taraxacum officinale, that is its scientific name, inspired legends and poems and has been used for centuries as a natural remedy for many ailments.
Now, thanks to a study conducted at the University of Trento, dandelions will inspire new engineered materials. The air trapping capacity of dandelion clocks submerged in water has been measured in the lab for the first time. The discovery paves the way for the development of new and advanced ...
2021-03-03
CLEMSON, South Carolina - Clemson University scientists have linked climatic fluctuations over the past one and a quarter-century with flower color changes.
Researchers combined descriptions of flower color from museum flower specimens dating back to 1895 with longitudinal- and latitudinal-specific climate data to link changes in temperature and aridity with color change in the human-visible spectrum (white to purple).
The study, which was published in the journal Proceedings of the Royal Society B, showed the change varied across taxa.
"Species ...
2021-03-03
PROVIDENCE, R.I. [Brown University] -- Humans have made a remarkable impact on the planet, from clearing forests for agriculture and urbanization to altering the chemistry of the atmosphere with fossil fuels. Now, a new study in the journal Nature reveals for the first time the extent of human impact on the global water cycle.
The study used NASA's Ice, Cloud and Land Elevation Satellite (ICESat-2) to assemble the largest ever dataset of seasonal water levels in more than 227,000 lakes, ponds and reservoirs worldwide. The data reveal that even though human-managed reservoirs comprise only a small percentage of all water bodies, they account for 57% of the total seasonal water storage changes globally.
"We ...
LAST 30 PRESS RELEASES:
[Press-News.org] Ghosts of past pesticide use can haunt organic farms for decades