Noisy waters can influence young-of-year lobsters' substrate choice and their antipredatory responses

Noise accelerates embryonic development in a key crab species: Morphological and physiological carryover effects on early life stages

Anthropogenic noise is considered one important global pollutant. The impact of noise on marine invertebrates has been less assessed. The present study evaluated the chronic effect of the motorboat noise obtained from a lagoon's soundscape, the natural habitat of the key crab Neohelice granulata, on its whole embryonic development, considering morphological and physiological carryover effects on embryos and hatched larvae. Results demonstrated that embryonic development was shortened under noise exposure. The effects on advanced embryos, larvae and adult females were: increased heartbeats and non-viable eggs, and decreased fecundity. Biochemical responses showed lipid peroxidation in embryos while antioxidant enzymes were activated in larvae and adults, indicating a counteracting effect related to the life stage. The negative effects on fitness offspring may imply ecological consequences at the population level. Results are discussed in terms of the ecosystem engineer species studied and the habitat, a MAB UNESCO Reserve lagoon, suggesting the urgent need to develop mitigation plans.

Anthropogenic noise limits resource distribution without changing social hierarchies

Increasing evidence demonstrates that anthropogenic noise is a global pollutant that threatens marine ecosystems. Mounting numbers of studies show its diverse effects on individuals and their behaviour. However, little is known about how individual changes in response to anthropogenic noise could cascade through groups and populations affecting resource distribution vital for survival and fitness. Here we test the hypotheses that anthropogenic noise could alter resource distribution, associated hierarchies and consequently individual benefits. We used groups of hermit crabs, a globally distributed model system for assessing impacts of environmental change on wildlife and measured in controlled laboratory conditions the resource distribution of their reusable shelters (gastropod shells) under ship noise and ambient control playbacks. We applied vacancy chain theory to test three predictions about how new resource units create benefits for a population. A new resource unit leads to (i) a cascade of resource abandonments and acquisitions (= chain of vacancy moves) based on an internal (ii) hierarchy (here size-based) which allows (iii) more than one individual to benefit. All three predictions were supported under control sound. Under anthropogenic noise however, fewer individuals benefitted from the arrival of a new, empty shell, while the size-based hierarchy was maintained. The latter was apparent in chain structures, which were concordant between sound treatments. This experiment shows that anthropogenic noise can affect individual behaviours that cascade through groups. This has the potential to disrupt wider resource distribution in populations.

Low-frequency noise pollution impairs burrowing activities of marine benthic invertebrates

Sounds from human activities such as shipping and seismic surveys have been progressively invading natural soundscapes and pervading oceanic ambient sounds for decades. Benthic invertebrates are important ecosystem engineers that continually rework the sediment they live in. Here, we tested how low-frequency noise (LFN), a significant component of noise pollution, affects the sediment reworking activities of selected macrobenthic invertebrates. In a controlled laboratory setup, the effects of acute LFN exposure on the behavior of three abundant bioturbators on the North Atlantic coasts were explored for the first time by tracking their sediment reworking and bioirrigation activities in noisy and control environments via luminophore and sodium bromide (NaBr) tracers, respectively. The amphipod crustacean Corophium volutator was negatively affected by LFN, exhibiting lower bioturbation rates and shallower luminophore burial depths compared to controls. The effect of LFN on the polychaete Arenicola marina and the bivalve Limecola balthica remained inconclusive, although A. marina displayed greater variability in bioirrigation rates when exposed to LFN. Furthermore, a potential stress response was observed in L. balthica that could reduce bioturbation potential. Benthic macroinvertebrates may be in jeopardy along with the crucial ecosystem-maintaining services they provide. More research is urgently needed to understand, predict, and manage the impacts of anthropogenic noise pollution on marine fauna and their associated ecosystems.

Reduction of environmental chemicals, toxicity and particulate matter in wet scrubber device to achieve zero emissions

The fine particles generated by the foundry industry are present in the atmosphere; they have an impact on the climate because of their influence on atmospheric radioactive phenomena. As a result of this scenario, there is a rising amount of legislation restricting the emission of pollutants from foundry industries and related businesses. In response to this situation, many researchers have concentrated on end-of-pipe technologies, one of which is the wet scrubber, which is a device that is primarily used in foundries to control pollution and is one of the devices that has been incorporated. The disadvantage of using this wet scrubber, on the other hand, is that it contributes to secondary pollution when it is used. In order to combat secondary pollution, a model of an enhanced wet scrubber system that incorporates a multi-sand filtering technology was developed. The performance of this redesigned wet scrubber system was evaluated with the use of computational fluid dynamics (CFD) software. In CFD, the Reynolds stress model was applied for simulation. The pressure magnitudes and velocity magnitudes are obtained by this simulation. The volume fraction of the dust was evaluated through the DPM approach. Because of the introduction of the filtration tank's computation, it was discovered that successful filtration was accomplished using sand filters, meaning that environmental chemicals and particles were totally filtered from 0.17 kg at the entrance to zero kg of particles at the outflow.