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1.
J Invertebr Pathol ; 198: 107936, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37196858

RESUMO

The springtail, Folsomia candida, is a soil arthropod commonly used to evaluate environmental toxins. Conflicting data on the toxicity of the herbicide paraquat prompted re-evaluation of its effects on F. candida survival and reproduction. Paraquat has an LC50 of about 80 µM when tested in the absence of charcoal; charcoal, often used in test arenas to facilitate visualization of the white Collembola, has a protective effect. Survivors of paraquat treatment fail to resume molting and oviposition, suggesting an irreversible effect on the Wolbachia symbiont that restores diploidy during parthenogenetic reproduction of this species.


Assuntos
Artrópodes , Wolbachia , Feminino , Animais , Paraquat , Solo , Carvão Vegetal , Reprodução
2.
Environ Res ; 201: 111495, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133973

RESUMO

Abrasion of tire wear is one of the largest sources of microplastics to the environment. Although most tire particles settle into soils, studies on their ecotoxicological impacts on the terrestrial environment are scarce. Here, the effects of tire particles (<180 µm) on three ecologically relevant soil invertebrate species, the enchytraeid worm Enchytraeus crypticus, the springtail Folsomia candida and the woodlouse Porcellio scaber, were studied. These species were exposed to tire particles spiked in soil or in food at concentrations of 0.02%, 0.06%, 0.17%, 0.5% and 1.5% (w/w). Tire particles contained a variety of potentially harmful substances. Zinc (21 900 mg kg-1) was the dominant trace element, whilst the highest concentrations of the measured organic compounds were detected for benzothiazole (89.2 mg kg-1), pyrene (4.85 mg kg-1), chlorpyrifos (0.351 mg kg-1), HCB (0.134 mg kg-1), methoxychlor (0.116 mg kg-1) and BDE 28 (0.100 mg kg-1). At the highest test concentration in soil (1.5%), the tire particles decreased F. candida reproduction by 38% and survival by 24%, and acetylcholinesterase (AChE) activity of P. scaber by 65%, whilst the slight decrease in the reproduction of E. crypticus was not dose-dependent. In food, the highest test concentration of tire particles reduced F. candida survival by 38%. These results suggest that micro-sized tire particles can affect soil invertebrates at concentrations found at roadsides, whilst short-term impacts at concentrations found further from the roadsides are unlikely.


Assuntos
Artrópodes , Oligoquetos , Poluentes do Solo , Acetilcolinesterase , Animais , Invertebrados , Microplásticos , Plásticos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
3.
Bull Environ Contam Toxicol ; 105(2): 244-249, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32556691

RESUMO

The aim of the study was to assess the effects of silver nanoparticles (AgNPs1 = 2.7 d·nm, AgNPs2 = 6.5 d·nm) and silver nitrate (AgNO3) on Enchytraeus crypticus and Folsomia candida using toxicity tests (OECD Guideline 220, 232). A 28-day chronic toxicity study was performed to evaluate the reproduction and mortality rate. E. crypticus reproduction was more sensitive to AgNO3 with a 28dEC50 of 86.40 (62.52-119.4) mg·kg-1 dry weight (d.w.) compared to AgNPs1 (28dEC50 = 119.3 (60.4-235.6) mg·kg-1 d.w). Similarly, the reproduction of F. candida was inhibited the most by AgNO3 with a 28dEC50 of 126.2 (104.2-152.9) mg·kg-1 d.w. followed by AgNPs1 (28dEC50 = 158.7 (64.05-393.2) mg·kg-1 d.w.) and AgNPs2 (28dEC50 = 206.4 (181.9-234.1) mg·kg-1 d.w.). No mortalities were observed for tested soil invertebrates exposed to AgNPs at concentrations up to 166 mg·kg-1 d.w. of AgNPs1 and 300 mg·kg-1 d.w. of AgNPs2, respectively. It was found that silver ions are more toxic in comparison with AgNPs.


Assuntos
Artrópodes/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Nitrato de Prata/toxicidade , Prata/toxicidade , Poluentes do Solo/toxicidade , Animais , Íons , Nanopartículas Metálicas/química , Reprodução/efeitos dos fármacos , Prata/química , Solo/química , Solo/normas , Poluentes do Solo/química , Testes de Toxicidade Crônica
4.
Bull Environ Contam Toxicol ; 104(4): 400-410, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32077985

RESUMO

The main aim of this short review was to assess the effect of test medium on the bioavailability of metals to the soil invertebrate Folsomia candida and the barley plant Hordeum vulgare. Solution-only exposures and sand-solution media were suitable media with control survival of > 80%. Comparing toxicity and accumulation data, LC50 and/or EC50 values as well as internal concentrations of cadmium (Cd) and copper (Cu) were similar in the tests with different porewater composition for springtails and barley plants. Similar results for toxicity and bioaccumulation of Cd and Cu using different test substrates, suggest the importance of physiological handling of the effects by the organisms rather than the influence of test medium composition.


Assuntos
Artrópodes/efeitos dos fármacos , Cádmio/toxicidade , Cobre/toxicidade , Hordeum/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Disponibilidade Biológica , Transporte Biológico , Cádmio/metabolismo , Cobre/metabolismo , Dose Letal Mediana , Solo/química , Poluentes do Solo/metabolismo
5.
Ecotoxicology ; 27(7): 764-771, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29616379

RESUMO

In the field, long-term exposure is a rule rather than an exception. As a consequence, the relatively short-term standard toxicity tests may not be adequate for assessing long-term effects of pesticide exposure. This study determined the toxicity of the neonicotinoid thiamethoxam, both pure and in the formulation Actara® (25% active substance), to the springtail Folsomia candida, over three generations (P, F1 and F2). For the parental generation (P), the toxicity of pure thiamethoxam and Actara® did not differ significantly, with LC50s and EC50s of 0.32-0.35 and 0.23-0.25 mg a.s./kg dry soil, respectively. For the F1 and F2 generations, LC50s were >0.37 mg a.s./kg dry soil for both compounds. Actara was more toxic towards reproduction in the F1 generation (EC50 0.16 mg a.s./kg dry soil) than pure thiamethoxam (EC50 0.23 mg a.s./kg dry soil). For generation F2, there was no significant difference in the toxicity of the compounds towards reproduction, with EC50s of >0.37 and 0.30 mg a.s./kg dry soil for Actara® and pure thiamethoxam respectively. These results suggest a slight decrease in the toxicity of the compounds throughout the generations tested. The similarity in the toxicity of pure and formulated thiamethoxam indicates that the ingredients in the formulation Actara® do not enhance toxicity.


Assuntos
Artrópodes/efeitos dos fármacos , Inseticidas/toxicidade , Poluentes do Solo/toxicidade , Tiametoxam/toxicidade , Animais , Dose Letal Mediana , Reprodução/efeitos dos fármacos , Testes de Toxicidade Crônica
6.
Ecotoxicol Environ Saf ; 139: 73-77, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28110048

RESUMO

Glycerol Monolaurate (GML) is a compound with known antimicrobial potential, however it is not much used due to its low solubility in water and high melting point. The nanoencapsulation of some drugs offers several advantages such as improved stability and solubility in water. The present study aimed to produce, characterize, and evaluate the ecotoxicity of GML nanocapsules. The nanocapsules were produced and presented a mean diameter of 210nm, polydispersity index of 0.044, and zeta potential of -23.4mV. The electron microscopy images showed the nanometric size and spherical shape. The assay in soil showed that GML has a high toxicity while the GML nanocapsules showed decreased toxic effects. Nanostructuration also protected the Rhamdia quelen against the toxic effects of GML. Concluding, the formulation shows positive results and is useful to predict the success of development besides not damaging the soil.


Assuntos
Anti-Infecciosos , Artrópodes/crescimento & desenvolvimento , Peixes/crescimento & desenvolvimento , Lauratos/toxicidade , Monoglicerídeos/toxicidade , Nanocápsulas/toxicidade , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/toxicidade , Artrópodes/efeitos dos fármacos , Ecotoxicologia , Exposição Ambiental
7.
Environ Manage ; 59(6): 1034-1042, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28275851

RESUMO

Growth of invasive, opportunistic plants (i.e. lampenflora) in popular tour caves is a significant concern for land managers worldwide. Numerous chemicals at various concentrations have been utilized to remove phototrophic lampenflora colonizing artificially lit surfaces within these caves; however formulations, effectiveness, and impacts appear anecdotal and temporally limited. At Crystal Cave, Sequoia National Park, California, we study lampenflora and cave springtail (Tomocerus celsus) response to a single 0.05 ml/cm2 dose of 1.0% sodium hypochlorite, 0.5% sodium hypochlorite, and 15.0% hydrogen peroxide compared to no treatment over the course of one year. Additionally, we explore potential food web impacts resulting from invasive lampenflora in naturally oligotrophic caves by utilizing stable isotope analysis of T. celsus found on and off lampenflora. Time-effect decay models indicate 1.0 and 0.5% sodium hypochlorite effectively eliminate lampenflora in 11 and 21 days, respectively, while lampenflora decay projections exceed 600 days with 15.0% hydrogen peroxide treatment. Repeat surveys of T. celsus indicate a negative response to 1.0% sodium hypochlorite (P = 0.02), and the probability of observing T. celsus was inversely related to the effectiveness of each treatment. Further, T. celsus had similar diets regardless of their lampenflora association (P = 0.92). We conclude that treatments of sodium hypochlorite at or below 0.5% achieve management goals with limited impacts to the presence or diet of a common cave-adapted indicator species.


Assuntos
Artrópodes/efeitos dos fármacos , Cavernas , Conservação dos Recursos Naturais/métodos , Espécies Introduzidas , Plantas/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Animais , California , Cadeia Alimentar , Parques Recreativos , Recreação
8.
BMC Evol Biol ; 16(1): 148, 2016 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-27423184

RESUMO

BACKGROUND: Climate oscillations in the Cenozoic reduced species richness and genetic diversity of terrestrial and aquatic animals and plants in central and northern Europe. The most abundant arthropods in temperate soils are Collembola that live in almost any soil-related habitat. Extant species show little morphological variation to Eocene fossils, suggesting persistence of species in stable habitats for millions of years. Collembola are able to evade adverse climatic conditions by moving into deeper soil layers and are tolerant to frost and draught. If these adaptations sufficed for surviving glacial periods remains open and needs to be investigated in a phylogeographic context, i.e. investigating spatial structure on molecular level. We investigated the molecular variation of three common species of Collembola at a pan-European scale to identify glacial refuges and post-glacial colonization patterns with three genetic markers. RESULTS: All genes revealed remarkable genetic structure between but not within populations, suggesting density dependent processes for establishment of populations (founder-takes-all principle), which is common for European animals and plants. In contrast to the post-glacial recolonization patterns of many aboveground organisms, divergence times of most geographic lineages indicate preservation of genetic structure since the Miocene. CONCLUSIONS: Collembola survived severe climatic changes including those during Quatenary glaciation and kept high genetic variance across Europe. Likely the buffering of temperature oscilliations in soil and the ability to evade adverse climatic conditions due to cold-tolerance and horizontal migration enabled Collembola to evade strong selective pressure of abiotic forces.


Assuntos
Artrópodes/genética , Evolução Molecular , Efeito Fundador , Animais , Mudança Climática , Europa (Continente) , Fósseis , Estruturas Genéticas , Variação Genética , Filogenia , Filogeografia
9.
J Exp Biol ; 219(Pt 16): 2567-76, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27312471

RESUMO

The ventral eye of the water-surface-inhabiting springtail Podura aquatica has six ommatidia with horizontal and vertical microvilli and perceives light from the ventral, frontal and frontodorsal regions, whereas the dorsal eye possesses two upward-looking ommatidia with vertical microvilli. The ventral eye may detect water by its polarization sensitivity, even if the insect is resting with its head slightly tipped down on a raised surface. The polarization sensitivity and polarotaxis in springtails (Collembola) have not been investigated. Therefore, we performed behavioural choice experiments to study them in P. aquatica We found that the strength of phototaxis in P. aquatica depends on the polarization characteristics of stimulating light. Horizontally and vertically polarized light were the most and least attractive, respectively, while unpolarized stimulus elicited moderate attraction. We show that horizontally polarized light attracts more springtails than unpolarized, even if the polarized stimulus was 10 times dimmer. Thus, besides phototaxis, P. aquatica also performs polarotaxis with the ability to measure or at least estimate the degree of polarization. Our results indicate that the threshold d* of polarization sensitivity in P. aquatica is between 10.1 and 25.5%.


Assuntos
Insetos/fisiologia , Luz , Água/química , Animais , Imageamento Tridimensional , Estimulação Luminosa , Polarimetria de Varredura a Laser
10.
Ecotoxicol Environ Saf ; 127: 22-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26796529

RESUMO

Mercury (Hg) is a highly toxic nonessential trace metal. Despite its natural occurrence in the Earth's Crust, its concentrations have been steadily increasing in the environment due to anthropogenic sources. Recent studies have showed great concern about soil fauna, once the potential adverse effects of mercury concentrations in the environment of these invertebrates are still poorly understood, especially when linked to forest soils and tropical biota. Different collembolan species can show distinct toxicity effects to the contaminants, impairing its developing lifelong and affecting its diversity and abundance in the environment. Laboratory studies were performed to evaluate the ecotoxicity of Hg(II) to collembolan species collected in Brazil, Proisotoma minuta (autochthonous) and Folsomia candida (allochthonous), as a tool to predict effects in ecological risk assessment of tropical regions. Behavioral, acute and chronic tests were carried under temperatures of 20°C and 24°C using two test soils, natural and artificial, spiked with increasing mercury concentrations. F. candida was more sensitive to mercury contamination than P. minuta, presenting the most restrictive values of EC50 and LC50. Reproduction was a considerably more sensitive endpoint than avoidance and mortality. The 28-day lower EC50 values were found in chronic tests for F. candida in natural soil to 24°C (3.32mgHgkg(-1)), while for P. minuta was in tropical artificial soil to 20°C (4.43mgHgkg(-1)). There were similarity for each collembolan species to respond at the Hg(II) effects when exposed at 20°C and 24°C. F. candida can be suitable as a bioindicator species to mercury ecotoxicity tests in tropical forest soils.


Assuntos
Artrópodes/efeitos dos fármacos , Monitoramento Ambiental , Mercúrio/toxicidade , Poluentes do Solo/toxicidade , Testes de Toxicidade , Animais , Bioensaio , Brasil , Ecotoxicologia , Floresta Úmida , Reprodução/efeitos dos fármacos , Medição de Risco
11.
Oecologia ; 179(2): 537-49, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26001605

RESUMO

Both the environment and the spatial configuration of habitat patches are important factors that shape community composition and affect species diversity patterns. Species have traits that allow them to respond to their environment. Our current knowledge on environment to species traits relationships is limited in spite of its potential importance for understanding community assembly and ecosystem function. The aim of our study was to examine the relative roles of environmental and spatial variables for the small-scale variation in Collembola (springtail) communities in a Dutch salt marsh. We used a trait-based approach in combination with spatial statistics and variance partitioning, between environmental and spatial variables, to examine the important ecological factors that drive community composition. Turnover of trait diversity across space was lower than for species diversity. Most of the variation in community composition was explained by small-scale spatial variation in topography, on a scale of 4-6 m, most likely because it determines the effect of inundation, which restricts where habitat generalists can persist. There were only small pure spatial effects on species and trait diversity, indicating that biotic interactions or dispersal limitation probably were less important for structuring the community at this scale. Our results suggest that for springtails, life form (i.e. whether they live in the soil or litter or on the surface/in vegetation) is an important and useful trait to understand community assembly. Hence, using traits in addition to species identity when analysing environment-organism relationships results in a better understanding of the factors affecting community composition.


Assuntos
Artrópodes/fisiologia , Ecossistema , Áreas Alagadas , Animais , Biodiversidade , Dinâmica Populacional , Solo
12.
J Econ Entomol ; 108(1): 228-36, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26470124

RESUMO

A series of experiments were conducted to determine the impact of Protaphorura fimata Gisin (Family: Onychiuridae) feeding on seeds and germinating seedlings of lettuce, Lactuca sativa L. (Asteraceae). First, various densities of P. fimata were incubated with 25 lettuce seeds for 7 d and feeding injury was evaluated in three soilless arena experiments. As a second step, 100 P. fimata were incubated with 25 lettuce seeds in three arena experiments with soil media. Finally, in a commercial field the incidence and impact of P. fimata on recently planted lettuce was assessed following applications of pyrethroid-insecticides: 2 d before planting, at planting, and 20 d later. In experiments without soil, the number of ungerminated seeds, feeding injury sites, and plants with injury were significantly greater in arenas with P. fimata than without. Similarly, the number of germinated seedlings, shoot fresh, and dry weights, and the length and width of fully opened-leaves were greater in arenas without than with P. fimata in assays with soil. In the field, P. fimata densities were significantly lower in beds that received insecticides at 2 d before and at planting than in untreated beds. Also, the fresh and dry weights of lettuce plants were significantly greater in the beds that received insecticide than in untreated. The results clearly show that P. fimata is a pest of lettuce and can cause severe feeding injury to germinating seeds or seedlings, thereby reducing their growth rate. The potential implications of P. fimata feeding and feeding injury characteristics are discussed.


Assuntos
Artrópodes , Herbivoria , Lactuca , Animais , California
13.
Cryobiology ; 69(1): 181-3, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25025820

RESUMO

A 9 kDA antifreeze protein (AFP) was isolated and purified from the Antarctic springtail, Gomphiocephalus hodgsoni. By combining selective sampling procedures and a modified ice affinity purification protocol it was possible to directly isolate a single AFP protein without recourse to chromatographic separation techniques. Mass spectrometry identified a single 9 kDa component in the purified ice fraction. Intramolecular disulphide bonding was suggested by the presence of 12 cysteine residues. The specific amino acid composition is unique, particularly with regard to the presence of histidine (11.5%). But it also shows noticeable commonalities with insect AFPs in the abundance of cysteine (13.8%), while simultaneously hinting, through the presence of glycine (11.5%), that the metabolic building blocks of AFPs in Collembola may have a phylogenetically-determined component.


Assuntos
Proteínas Anticongelantes/química , Proteínas Anticongelantes/isolamento & purificação , Adaptação Fisiológica , Animais , Regiões Antárticas , Artrópodes , Temperatura Baixa , Gelo/efeitos adversos , Espectrometria de Massas , Estrutura Secundária de Proteína
14.
Environ Toxicol Chem ; 43(5): 1090-1096, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38421212

RESUMO

Biotic ligand modeling (BLM) approaches are already applied to predict the bioavailability and possible risk of metals in surface water, but need further development for soils. The present study investigated the effect of major cations (Ca2+, Mg2+, Na+, K+, and H+) on cadmium bioaccumulation in the springtail Folsomia candida. To avoid the complexity of real soils and enable control of elemental speciation in the exposure medium, the animals were exposed to different cadmium concentrations in an inert quartz sand-solution medium. Accumulation of cadmium in the animals was measured after 7 days exposure at different cation concentrations. Among the cations, only Ca2+ significantly affected the uptake of cadmium in the springtails. Mg2+ also had higher effects compared with other selected cations. Using a BLM approach, the uptake of cadmium in the animals predicted by taking into account both Ca2+ and Mg2+ activities correlated well with the measured values (R2 = 0.68). The final estimated conditional binding constants for cadmium (log KCd-BL), Ca (log KCa-BL), and Mg (log KMg-BL) of 1.06, 2.14, and 1.23 L/mol, respectively, were in agreement with previously reported values. The match between predicted and measured uptake data confirms the applicability and usefulness of the BLM for predicting the bioavailability of cadmium to springtails and opens the way for its application in soil. Environ Toxicol Chem 2024;43:1090-1096. © 2024 SETAC.


Assuntos
Cádmio , Cátions , Poluentes do Solo , Animais , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Artrópodes/efeitos dos fármacos , Artrópodes/metabolismo , Areia , Ligantes , Modelos Biológicos
15.
Ecol Evol ; 14(6): e11519, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895565

RESUMO

Biodiversity patterns are shaped by the interplay between geodiversity and organismal characteristics. Superimposing genetic structure onto landscape heterogeneity (i.e., landscape genetics) can help to disentangle their interactions and better understand population dynamics. Previous studies on the sub-Antarctic Prince Edward Islands (located midway between Antarctica and Africa) have highlighted the importance of landscape and climatic barriers in shaping spatial genetic patterns and have drawn attention to the value of these islands as natural laboratories for studying fundamental concepts in biology. Here, we assessed the fine-scale spatial genetic structure of the springtail, Cryptopygus antarcticus travei, which is endemic to Marion Island, in tandem with high-resolution geological data. Using a species-specific suite of microsatellite markers, a fine-scale sampling design incorporating landscape complexity and generalised linear models (GLMs), we examined genetic patterns overlaid onto high-resolution digital surface models and surface geology data across two 1-km sampling transects. The GLMs revealed that genetic patterns across the landscape closely track landscape resistance data in concert with landscape discontinuities and barriers to gene flow identified at a scale of a few metres. These results show that the island's geodiversity plays an important role in shaping biodiversity patterns and intraspecific genetic diversity. This study illustrates that fine-scale genetic patterns in soil arthropods are markedly more structured than anticipated, given that previous studies have reported high levels of genetic diversity and evidence of genetic structing linked to landscape changes for springtail species and considering the homogeneity of the vegetation complexes characteristic of the island at the scale of tens to hundreds of metres. By incorporating fine-scale and high-resolution landscape features into our study, we were able to explain much of the observed spatial genetic patterns. Our study highlights geodiversity as a driver of spatial complexity. More widely, it holds important implications for the conservation and management of the sub-Antarctic islands.

16.
Mitochondrial DNA B Resour ; 9(1): 178-181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38288250

RESUMO

The complete mitochondrial genome of Tomocerus caputiviolaceus was sequenced and assembled. The complete mitochondrial genome is 15,519 bp in length. The mitogenome contained 37 genes, including 13 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs. In phylogenetic analysis based on the nucleotide sequences of 13 PCGs, T. caputiviolaceus is closely related to Tomocerus qinae Yu, Yao & Hu, 2016, both of which belong to the genus Tomocerus within the family Tomoceridae.

17.
ACS Nano ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315048

RESUMO

Developing a superomniphobic surface that exceeds the static and dynamic repellency observed in nature's springtails for various liquids presents a significant challenge in the realm of surface and interface science. However, progress in this field has been particularly limited when dealing with low-surface-tension liquids. This is because dynamic repellency values are typically at least 2 orders of magnitude lower than those observed with water droplets. Our study introduces an innovative hierarchical topography demonstrating exceptional dynamic repellency to low-surface-tension liquids. Inspired by the structural advantages found in springtails, we achieve a static contact angle of >160° and the complete rebound of droplet impact with a Weber number (We) of ∼104 using ethanol. These results surpass all existing benchmarks that have been reported thus far, including those of natural surfaces. The key insight from our research is the vital role of the microscale air pocket size, governed by wrinkle wavelength, in both static and dynamic repellency. Additionally, nanoscale air pockets within serif-T nanostructures prove to be essential for achieving omniphobicity. Our investigations into the wetting dynamics of ethanol droplets further reveal aspects such as the reduction in contact time and the occurrence of a fragmentation phenomenon beyond We ∼ 350, which has not been previously observed.

18.
Environ Toxicol Chem ; 43(5): 1173-1183, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38546206

RESUMO

Current standard toxicity tests on nontarget soil invertebrates mainly focus on the endpoints survival and reproduction. Such results are likely insufficient to predict effects at higher organizational levels, for example, the population level. We assessed the effects of exposure to the pesticide teflubenzuron on the collembolan Folsomia candida, by performing a full life-cycle experiment exposing single individuals via contaminated food (uncontaminated control and 0.2, 0.32, 0.48, 0.72, 1.08, and 1.6 mg/kg dry yeast). Several life-history traits were considered by following the growth and development of newly hatched individuals over a period of 65 days. We assessed survival, body length, time to first oviposition, cumulative egg production, and hatchability of eggs. A two-stage model was applied to calculate the population growth rate (λ) combined with elasticity analysis to reveal the relative sensitivity of λ to the effects of teflubenzuron on each life-history parameter. Body length was the least sensitive life-history parameter (median effective concentration = 1.10 mg teflubenzuron/kg dry yeast) followed by time to first oviposition (0.96 mg/kg), survival (median lethal concentration = 0.87 mg/kg), cumulative egg production (0.32 mg/kg), and egg hatchability (0.27 mg/kg). Population growth decreased with increasing concentrations of teflubenzuron (λ = 1.162/day in control to 1.005/day in 0.72 mg/kg dry yeast, with populations going extinct at 1.08 and 1.6 mg/kg dry yeast). Elasticity analysis showed that changes in juvenile survival had a greater impact on the population growth rate compared with the other life-history traits. Our study provides a comprehensive overview of individual-level effects of long-term exposure to teflubenzuron and integrates these effects to assess the potential risk to collembolan populations. Environ Toxicol Chem 2024;43:1173-1183. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Artrópodes , Benzamidas , Hormônios Juvenis , Crescimento Demográfico , Animais , Hormônios Juvenis/toxicidade , Hormônios Juvenis/farmacologia , Benzamidas/toxicidade , Benzamidas/farmacologia , Artrópodes/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Éteres Fenílicos/toxicidade , Feminino
19.
Environ Toxicol Chem ; 42(7): 1516-1528, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37036256

RESUMO

Neonicotinoids have been among the most widely and abundantly used insecticides for most of the current century. The effects of these substances on nontarget terrestrial and aquatic organisms have resulted in a significant decrease in their use in many parts of the world. In response, the application of several novel classes of insecticides including diamides, ketoenols, pyridines, and butenolides has significantly increased. The hexapod subclass Collembola is an ecologically significant and widely distributed group of soil invertebrates often found in leaf litter and in surficial soils. We exposed the parthenogenic collembolan species Folsomia candida to six insecticides in a sandy loam soil for 28 days, including two neonicotinoids (thiamethoxam and clothianidin), a diamide (cyantraniliprole), a ketoenol (spirotetramat), a pyridine (flonicamid), and a butanolide (flupyradifurone) to assess the effect of each insecticide on survival and reproduction. Clothianidin, thiamethoxam, and cyantraniliprole (median effective concentration [EC50] values for reproduction: 0.19, 0.38, and 0.49 mg/kg soil, respectively) had a greater effect on survival and reproduction of F. candida than flupyradifurone, spirotetramat, and flonicamid (EC50 values for reproduction: 0.73, >3.08, and 5.20 mg/kg soil, respectively). All significant impacts found in our study were observed at concentrations below concentrations of the active ingredients that would be expected in agricultural soils. Environ Toxicol Chem 2023;42:1516-1528. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Artrópodes , Inseticidas , Animais , Inseticidas/toxicidade , Tiametoxam , Neonicotinoides , Reprodução , Solo/química
20.
Sci Total Environ ; 857(Pt 3): 159690, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36302410

RESUMO

The ecotoxicological effects of microplastics, a new and widespread ecosystem pollutant, have been extensively reported. However, it remains unclear whether soil fauna transfer microplastics and whether migration behaviours influence subsequent ecological functions in terrestrial ecosystems. We investigated the transfer patterns of microplastics and their adsorbed substances by soil animals (the springtail, Folsomia candida) and the effect of the transfer on the decomposition of soil organic matter through a standardized cotton strip assay. The results showed that springtails had a strong ability to transfer microplastics into the soil. The adsorbed nutrient (nitrogen; N), pollutant (cadmium; Cd), and green fluorescent Escherichia coli (GFP-E. coli) were also transferred with the microplastics. In addition, cotton strip decomposition was accelerated when the microplastics adsorbed N, but the adsorption of Cd decreased decomposition. These ecological effects were particularly strong for small microplastics. Microplastic transfer regulated soil bacterial communities, promoting the growth of Ascomycota fungi and inhibiting that of Basidiomycota, leading to cotton strip decomposition. Thus, microplastic pollution may occur at one site, but microplastics can be transferred anywhere in terrestrial ecosystems by soil animals and adsorb other substances, including nutrients and pollutants, that affect ecosystem function. Therefore, more studies on the migration behaviour of microplastics are necessary.


Assuntos
Microplásticos , Poluentes do Solo , Animais , Solo , Plásticos , Ecossistema , Poluentes do Solo/toxicidade , Cádmio , Escherichia coli
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