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Lundgren Bendix posted an update 6 months, 2 weeks ago
t waves should continue in order to ensure adequate adaptation in the future.Global demand for silver nanoparticles (AgNPs), and their inevitable release into the environment, is rapidly increasing. AgNPs display antimicrobial properties and have previously been recorded to exert adverse effects upon marine phytoplankton. However, ecotoxicological research is often compromised by the use of non-ecologically relevant conditions, and the mechanisms of AgNP toxicity under environmental conditions remains unclear. To examine the impact of AgNPs on natural marine communities, a natural assemblage was exposed to citrate-stabilised AgNPs. Here, investigation confirmed that the marine dominant cyanobacteria Prochlorococcus is particularly sensitive to AgNP exposure. Whilst Prochlorococcus represents the most abundant photosynthetic organism on Earth and contributes significantly to global primary productivity, little ecotoxicological research has been carried out on this cyanobacterium. To address this, Prochlorococcus was exposed to citrate-stabilised AgNPs, as well as silver in its ionic fo and biogeochemical cycling, their higher susceptibility to AgNP exposure is a concern in hotspots of pollution.The migration of geogenic gases in continental areas with geothermal activity and active faults is an important process releasing greenhouse gases (GHG) to the lower troposphere. In this respect, caves in hypogenic environments are natural laboratories to study the compositional evolution of deep-endogenous fluids through the Critical Zone. Vapour Cave (Alhama, Murcia, Spain) is a hypogenic cave formed by the upwelling of hydrothermal CO2-rich fluids. Anomalous concentrations of N2O and NO2 were registered in the cave’s subterranean atmosphere, averaging ten and five times the typical atmospheric backgrounds, respectively. We characterised the thermal conditions, gaseous compositions, sediments, and microbial communities at different depths in the cave. We did so to understand the relation between N-cycling microbial groups and the production and transformation of nitrogenous gases, as well as their coupled evolution with CO2 and CH4 during their migration through the Critical Zone to the lower troposphere. Oaviour of this and other archaeal phyla.Mortality and metabolic responses of four-armed larvae of Strongylocentrotus intermedius under CO2-induced seawater acidification were investigated. Gametes of S. intermedius were fertilized and developed to the four-armed larval stage in either current natural seawater pH levels (as Control; pH = 7.99 ± 0.01) or laboratory-controlled acidified conditions (OA1 ΔpH = -0.3 units; OA2 ΔpH = -0.4 units; OA3 ΔpH = -0.5 units) according to the predictions of the Intergovernmental Panel on Climate Change (IPCC). The degrees of spicule exposure and asymmetry and mortality of four-armed larvae of S. intermedius were observed; each had a significant linearly increasing trend as the seawater pH level decreased. Comparative metabolome analysis identified a total of 87 significantly differentially expressed metabolites (SDMs, UP 57, DOWN 30) in OA-treated groups compared with the control group. Twenty-three SDMs, including carnitine, lysophosphatidylcholine (LPC) 183, lysophosphatidyl ethanolamine (LPE) 161, glutathione (GSH) and L-ascorbate, exhibited a linear increasing trend with decreasing seawater pH. Nine SDMs exhibited a linear decreasing trend as the seawater pH declined, including hypoxanthine, guanine and thymidine. Among all SDMs, we further mined 48 potential metabolite biomarkers responding to seawater acidification in four-armed larvae of S. intermedius. These potential metabolite biomarkers were mainly enriched in five pathways glycerophospholipid metabolism, glutathione metabolism, purine metabolism, pyrimidine metabolism and the tricarboxylic acid cycle (TCA cycle). Our results will enrich our knowledge of the molecular mechanisms employed by sea urchins in response to CO2-induced seawater acidification.Our work addresses a neglected aspect of heavy metal (HM) pollution of sediments in small floodplain reservoirs. Very little is known about this type of water bodies, in contrast to oxbow lakes or old river beds. The study examines the spatial horizontal distribution of HM and the effect of texture, organic carbon (OC) content, morphometric and location features on HM concentrations. Moreover, the data from the assessment of sediment toxicity were analysed with respect to recent years’ droughts to estimate the potential toxicity of sediments as soils. The statistical analyses showed that the texture and the OC content had a significant impact on the HM concentrations. Fine-grained and OC-rich sediments exhibited higher HM pollution. Only one morphometric/location factor was shown to affect HM levels in sediments – the angle between the reservoir axis and the riverbed. The angle value affected the texture and, consequently, the HM content with a rising angle the share of the coarse-grained fraction increased leading to a decrease in the HM concentration. The spatial horizontal HM distribution did not show statistically significant results, nonetheless, HM content was found to rise along with the distance from the initial part of reservoir. The toxicity levels were not exceeded in sediments, however, the evaluation of the material as soil showed that, according to European Union guidelines, the content of at least one HM was toxic in 80% of the samples. Epertinib Contaminated floodplain reservoirs should be regarded as a double threat to riverine ecosystems. On the one hand, they are one of the main non-point sources of river valley pollution; on the other hand, given the drying up of reservoirs, sediments become soils and the soil-bound heavy metals become more toxic to the environment.Hyperaccumulation describes plants’ ability to take up high amounts of soil metals such as Ni and allocate them to aboveground tissues. Little is known, however, about the rate at which Ni is allocated to different plant parts, or about the consumers related to these parts, including their pollinator mutualists. In this study, we examine the interface between the serpentine endemic Ni-hyperaccumulator Odontarrhena lesbiaca and its consumers of different plant parts leaves (consumers), floral parts (consumers and primitive pollinators), and floral rewards (true pollinators). The study was conducted at two serpentine areas on Lesvos, Greece. Over 13 rounds of sampling during the flowering period of O. lesbiaca in both areas we collected plant stems with flowers, consumers of different plant parts, and flower visitors. Collected animals were mainly insects and some spiders. Chemical analyses showed negligible Ni-concentration differences between the two areas. Among all plant parts, the lowest Ni concentration was found in pollen and the highest in leaves.