Little is known about the non-target effects of glyphosate active ingredients (GLY) versus glyphosate-based herbicide (GBH) formulations on soil organisms, and whether effects are influenced by environmental conditions. We investigated the avoidance behavior, biomass growth, and reproduction of earthworms (Eisenia fetida, E. andrei) in response to two GLYs (glyphosate ammonium and potassium salt), the corresponding GBHs (Touchdown Quattro, Roundup PowerFlex) containing these GLYs, and the “inert” co-formulant alkylpolyglycoside (APG) at two temperature (15 °C vs. 20 °C) and soil organic matter levels (3.2% vs. 4.3%). Earthworm avoidance was lower at high soil organic matter content, but remained unaffected by substances and temperature. Earthworm biomass growth and reproduction (cocoons and juveniles) were significantly affected by substances and temperature; reproduction was also affected by a substance and temperature interaction. Biomass growth was almost zero at higher temperature; reproduction was generally higher at higher temperature. More cocoons were produced under Roundup PowerFlex than under the corresponding AI, due to the impact of the co-formulant APG. No other differences were observed between GBH and the corresponding AIs. We conclude that the non-target effects of pesticides can only be fully assessed if all ingredients in a formulation are known and environmental parameters are included in environmental risk assessments.

Glyphosate is the most widely used active ingredient (AI) in glyphosate-based herbicides (GBHs) worldwide and is also known to affect a variety of soil organisms. However, we know little about how the effects of glyphosate AIs differ from those of GBHs that also contain so-called inert co-formulants. We conducted a greenhouse experiment using the model cover crop white mustard (Sinapis alba) to investigate the effects of three GBHs (Roundup PowerFlex, Roundup LB Plus, and Touchdown Quattro) and their respective glyphosate AIs (glyphosate potassium, isopropylamine, and diammonium salt) on epedaphic springtails (Sminthurinus niger; Collembola) activity in soils with low (3.0%) or high (4.1%) organic matter content (SOM). Springtail activity was assessed using pitfall traps. Most GBHs and AIs reduced springtail activity compared to mechanical removal of mustard in the short-term and even up to 5 months after application. GBHs and AIs differed considerably in their effects on springtail activity, and effects were modified by SOM content. Our results highlight the need to (i) distinguish between the effects of glyphosate AIs and commercial GBH formulations, (ii) disclose all ingredients of GBHs, as co-formulants also affect non-target organisms, and (iii) include soil properties in ecotoxicological risk assessments for soil organisms to better characterize the situation in the field.

Glyphosate is the most widely used active ingredient (AI) in thousands of glyphosate-based herbicides (GBHs) worldwide. Short-term impacts of AIs or GBHs on earthworms are well known, but few studies have examined long-term legacy effects >3 months after application. In a pot experiment, we studied both short-term and long-term effects on deep burrowing earthworms (Lumbricus terrestris) and soil functions. Therefore, the cover crop Sinapis alba was grown in soils with either 3.0% or 4.1% soil organic matter content (SOM) and either sprayed with a GBH (Touchdown Quattro, Roundup PowerFlex, or Roundup LB Plus) or the respective glyphosate AI (diammonium-, potassium-, or isopropylamine-salt) or hand weeded (control). Long-term effects showed increased earthworm activity under GBHs even 4 months after application, but similar activity under AIs and control. Another application of the same treatments 5 months after the previous one also increased earthworm activity under GBHs, especially at high SOM levels. Water infiltration after a simulated heavy rainfall was 50% lower, and leaching was 30% higher under GBH than under AI application or hand weeding. Individual GBHs and AIs varied in their effects and were influenced by SOM and soil moisture. Full disclosure of all ingredients in GBH formulations would be necessary to allow a comprehensive assessment of environmental risks.

Artificial light at night (ALAN), also known as light pollution, is a growing environmental problem worldwide. However, only a few studies have examined whether soil organisms that search for food at the surface at night can be affected by ALAN. We investigated the effects of ALAN on the above-ground foraging activity of anecic earthworms (Lumbricus terrestris), on the soil water infiltration and on the germination and growth of a cover crop (Phacelia tanacetifolia). In a full-factorial greenhouse experiment, we tested four factors: ALAN (about 5 lx during the night vs. total darkness), earthworms (two specimens vs. none), plant species (Phacelia alone vs. mixed with ragweed Ambrosia artemisiifolia) and sowing depth (surface-sown vs. sown in 5 cm depth). Data were analysed using multifactorial ANOVAs. Earthworms removed 51% less surface litter under ALAN than under dark conditions. ALAN had no effect on Phacelia germination but resulted in increased height growth and biomass production when the seeds were buried. Earthworms reduced Phacelia germination and biomass production. ALAN reduced water leaching through the experimental units, probably due to interactions between the subsurface casts and plant roots. We conclude that ALAN, as emitted from streetlights, can lead to complex ecological effects in ecosystems that merit further investigation.

Effects of mowing on vegetation parameters have been well studied. However, less is known about mowing effects on soil fauna and if soil properties alter this. We investigated earthworm communities in a long-term experiment 14 years after its establishment in 5 dry, fresh and moist grassland plots located in the Natura 2000 site Lainzer Tiergarten near Vienna, Austria (238–402 m a.s.l., 48°10′ N, 16°12′ E). The grasslands were either mowed once a year or every second year, or not mowed since being established. Earthworms were assessed using the non-destructive octet electro-shocking method. Additionally, vegetation composition, soil conductivity, temperature and moisture were assessed. We found 13 earthworm species across all treatments, although their abundance was generally low with 6.1 ± 4.7 worms m⁻². The total earthworm abundance and species diversity was higher in dry compared to fresh and moist grasslands but was not affected by mowing frequency. Endogeic earthworms (Aporrectodea caliginosa, Aporrectodea rosea) and epigeics (Lumbricus rubellus) were more tolerant to mowing than anecics (Lumbricus terrestris, Allolobophora longa). Since plant species richness was highest in annually mown grasslands and earthworm species richness was positively related to plant species numbers, we recommend regular, low-input management to promote above- and belowground biodiversity in these grasslands.

Fluopyram is a broad-spectrum fungicide and nematicide used in foliar sprays and seed treatments. Despite its low volatility and moderate solubility, it is frequently detected beyond application sites in air, soil, and water. As a per- and polyfluoroalkyl substance (PFAS)-class “forever chemical”, its off-site presence raises ecotoxicological concerns. We conducted a 61-day greenhouse experiment to assess the effects of fluopyram residues in soil (0, 0.02, 0.04, and 0.78 mg kg⁻¹ soil) on two cover crop species (Italian clover, Trifolium incarnatum; cornflower, Centaurea cyanus), earthworms (Lumbricus terrestris), springtails (Folsomia candida), and litter decomposition. Measured endpoints included plant establishment, growth, biomass, photosynthetic efficiency, root architecture, soil fauna activity, and litter breakdown. Responses were species-specific and did not exhibit clear dose–response relationships. Height growth in Italian clover and cornflower showed significant treatment × date interactions, whereas establishment and biomass production remained unaffected. In Italian clover, root diameter increased with fluopyram concentration, while root length and volume showed non-significant trends. Cornflower roots exhibited fewer crossings at higher concentrations but were otherwise unaffected. Photosynthetic efficiency remained unchanged in both species, although it tended to decrease modestly in cornflower at the highest concentration. Springtail surface activity density was generally influenced by fluopyram, with significant treatment × date interactions at 0.04 and 0.78 mg kg⁻¹. Earthworm effects were inconclusive due to low survival rates. Neither litter decomposition rate nor stabilization factor was affected. Our results show that fluopyram residues in soil can induce subtle, species-specific effects in non-target organisms. However, long-term studies are needed to clarify how this highly persistent active ingredient and its degradation products accumulate in soils and interact with co-occurring pesticides, thereby improving ecological risk assessments.