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1.
Glob Chang Biol ; 30(3): e17211, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38439736

RESUMO

Most protected area (PA) planning aims to improve biota representation within the PA system, but this does not necessarily achieve the best outcomes for biota retention across regions when we also consider habitat loss in areas outside the PA system. Here, we assess the implications that different PA expansion strategies can have on the retention of species habitat across an entire region. Using retention of forest habitat for Colombia's 550 forest-dependent bird species as our outcome variable, we found that when a minimum of 30% of each species' habitat was included in the PA system, a pattern of PA expansion targeting areas at highest deforestation risk (risk-prevention) led to the retention, on average, of 7.2% more forest habitat per species by 2050 than did a pattern that targeted areas at lowest risk (risk-avoidance). The risk-prevention approach cost more per km2 of land conserved, but it was more cost-effective in retaining habitat in the landscape (50%-69% lower cost per km2 of avoided deforestation). To have the same effectiveness preventing habitat loss in Colombia, the risk-avoidance approach would require more than twice as much protected area, costing three times more in the process. Protected area expansion should focus on the contributions of PAs to outcomes not only within PA systems themselves, but across entire regions.


La mayor parte de la planificación de áreas protegidas (AP) tiene como objetivo mejorar la representación de la biota dentro del sistema de AP, pero esto no necesariamente logra los mejores resultados para la retención de biota a nivel de paisaje cuando también consideramos la pérdida de hábitat en áreas fuera del sistema de AP. Aquí evaluamos las implicaciones que diferentes estrategias de expansión de AP pueden tener en la retención del hábitat de las especies en toda una región. Utilizando la retención de hábitat forestal para las 550 especies de aves dependientes de bosque de Colombia como nuestra variable de resultado, encontramos que cuando un mínimo del 30% del hábitat de cada especie es incluido en el sistema de AP, se observó que un patrón de expansión de AP dirigido a áreas con mayor riesgo de deforestación (prevención de riesgos) condujo a la retención, en promedio, de un 7.2% más de hábitat por especie para 2050 que un patrón enfocado en áreas con menor riesgo (evasión de riesgos). El enfoque de prevención de riesgos costó más por km2 de tierra conservada, pero fue más rentable para retener el hábitat en el paisaje (entre un 50% y un 69% menos costo por km2 de deforestación evitada). Para tener la misma eficacia en la prevención de la pérdida de hábitat en Colombia, el enfoque de evasión de riesgos requeriría más del doble de área protegida, lo que costaría tres veces más en el proceso. La expansión de las AP debería centrarse en las contribuciones de las AP a los resultados no sólo dentro de los propios sistemas de AP, sino en regiones enteras.


Assuntos
Biota , Florestas , Colômbia
2.
Sci Rep ; 14(1): 5261, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438419

RESUMO

Drivers and dynamics of initial human migrations across individual islands and archipelagos are poorly understood, hampering assessments of subsequent modification of island biodiversity. We developed and tested a new statistical-simulation approach for reconstructing the pattern and pace of human migration across islands at high spatiotemporal resolutions. Using Polynesian colonisation of New Zealand as an example, we show that process-explicit models, informed by archaeological records and spatiotemporal reconstructions of past climates and environments, can provide new and important insights into the patterns and mechanisms of arrival and establishment of people on islands. We find that colonisation of New Zealand required there to have been a single founding population of approximately 500 people, arriving between 1233 and 1257 AD, settling multiple areas, and expanding rapidly over both North and South Islands. These verified spatiotemporal reconstructions of colonisation dynamics provide new opportunities to explore more extensively the potential ecological impacts of human colonisation on New Zealand's native biota and ecosystems.


Assuntos
Biodiversidade , Ecossistema , Humanos , Biota , Arqueologia , Atividades Humanas
3.
Zootaxa ; 5415(4): 501-528, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38480186

RESUMO

Being areas of biotic overlap located between biogeographic regions, transition zones function as natural laboratories. The present study explores the phylogenetic history of the dung beetle subfamily Scarabaeinae, in order to present an evolutionary scenario that allows inference of the biogeographic history of the Mexican Transition Zone (MTZ) and integration of the distributional patterns of its biota. The species sampling included 94 New World taxa (93 species of Scarabaeinae and one species of Aphodiinae). The phylogenetic relationships of the main clades recovered in our study were supported with PP values 0.95. Based on the BAYAREALIKE model to reconstruct the ancestral distributional patterns of Scarabaeinae, we inferred a complex scenario with 19 dispersal events, 15 vicariance events, and three extinctions. We suggest that the Ancient Neotropical and Tropical Paleoamerican patterns represent the most likely ancestral distributional patterns for the Scarabaeinae of the MTZ, which probably settle there during the Eocene-Oligocene. The rest of the Scarabaeinae distributional patterns were assembled in subsequent periods. The results suggest that the MTZ had two separate formation stages: a Paleo-MTZ (Eocene-Miocene) and a current MTZ (Pliocene-Anthropocene). We conclude that the evolutionary history as well as the dispersal-vicariance scenario for the Scarabaeinae of the MTZ fits the out of the tropics model.


Assuntos
Besouros , Animais , Filogenia , Besouros/genética , Evolução Biológica , México , Biota
4.
Ecol Lett ; 27(2): e14370, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348631

RESUMO

Species coexistence in ecological communities is a central feature of biodiversity. Different concepts, i.e., contemporary niche theory, modern coexistence theory, and the unified neutral theory, have identified many building blocks of such ecological assemblies. However, other factors, such as phenotypic plasticity and stochastic inter-individual variation, have received little attention, in particular in animals. For example, how resource polyphenisms resulting in predator-prey interactions affect coexistence is currently unknown. Here, we present an integrative theoretical-experimental framework using the nematode plasticity model Pristionchus pacificus with its well-studied mouth-form dimorphism resulting in cannibalism. We develop an individual-based model that relies upon synthetic data based on our empirical measurements of fecundity and polyphenism to preserve demographic heterogeneity. We demonstrate how the interplay between plasticity and individual stochasticity result in all-or-nothing outcomes at the local level. Coexistence is made possible when spatial structure is introduced.


Assuntos
Nematoides , Comportamento Predatório , Animais , Fertilidade , Biota , Dinâmica Populacional
5.
Harmful Algae ; 132: 102565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38331537

RESUMO

Benthic dinoflagellates produce potent toxins that may negatively affect humans and the marine biota. Understanding the factors that stimulate their growth is important for management strategies and to reduce their potential negative impacts. Laboratory cultures have been extensively used to study microalgae physiology and characterize life cycles, nutrition, growth rates, among other processes. A systematic review of the literature on the growth parameters of the benthic dinoflagellates Ostreopsis cf. ovata, Prorocentrum lima species complex and Coolia malayensis obtained in laboratory cultures of strains isolated from all over the world was performed. The effects of temperature, light intensity, photoperiod, salinity and culture media on the growth rate of these species were evaluated using multiple regressions and a model selection approach, based on the Akaike Information Criteria (AIC). The potential effects of the initial culture abundance and the media volume used on the growth of the species were also assessed. Data from 50 articles (25 for O. cf. ovata, 21 for P. lima and 6 for C. malayensis), resulting in 399 growth parameter values (growth rate, doubling time and maximum yield) were compiled in a database. The genetic clades of O. cf. ovata and P. lima species complex were also noted. Growth rate was the most frequently reported growth parameter for the three species, and 127 values were retrieved for O. cf. ovata, 90 for P. lima and 56 for C. malayensis. Temperature was the factor that best explained the growth response of P. lima and C. malayensis, whereas for O. cf. ovata, temperature and salinity were equally important. Light intensity and photoperiod were included among the six best models for the studied species but presented a weaker effect on growth. Given the observed and future projected climate change, increasing ocean temperature will promote the growth of these species, likely leading to an expansion of their impacts on ecosystems and human health. The use of common garden experiments using multiple strains from different geographic domains, particularly addressing underrepresented lineages is recommended, as they will provide more balanced insight regarding the species physiological responses to environmental drivers.


Assuntos
Dinoflagelados , Humanos , Dinoflagelados/fisiologia , Ecossistema , Toxinas Marinhas , Biota
6.
Ecol Appl ; 34(2): e2947, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38305124

RESUMO

Revegetation plantings are a key activity in farmland restoration and are commonly assumed to support biotic communities that, with time, replicate those of reference habitats. Restoration outcomes, however, can be highly variable and difficult to predict; hence there is value in quantifying restoration success to improve future efforts. We test the expectation that, over time, revegetation will restore bird communities to match those in reference habitats; and assess whether specific planting attributes enhance restoration success. We surveyed birds in 255 sites in south-east Australia, arranged along a restoration gradient encompassing three habitat types: unrestored farmland (paddocks), revegetation plantings (comprising a chronosequence up to 52 years old) and reference habitats (remnant native vegetation). Surveys were undertaken in 2006/2007 and again in 2019, with data used to compare bird assemblages between habitat types. We also determined whether, in the intervening 12 years, bird communities in revegetation had shifted toward reference habitats on the restoration gradient. Our results showed that each habitat contained a unique bird community and that, over time, assemblages in revegetation diverged away from those in unrestored farmland and converged toward those in reference habitats. Two planting attributes influenced this transition: the bird assemblages of revegetation were more likely to have diverged away from those of unrestored farmland (with scattered mature trees) 12 years later if they were located in areas with more surrounding tree cover, and were mostly ungrazed by livestock (compared with grazed plantings). Our results highlight three key ways in which revegetation contributes to farmland restoration: (1) by supporting richer and more diverse bird assemblages than unrestored farmland, (2) by enhancing beta diversity in rural landscapes through the addition of a unique bird community, and (3) by shifting bird assemblages toward those found in reference habitats over time. However, revegetation plantings did not replicate reference habitats by ~40-50 years in our region, and complete convergence may take centuries. These findings have implications for environmental offset programs and mean that effective conservation in farmland environments depends on the retention and protection of natural and seminatural habitats as a parallel management strategy to complement restoration.


Assuntos
Biota , Aves , Animais , Fazendas , Gado , Árvores
7.
J Environ Manage ; 354: 120217, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340666

RESUMO

The underground community of soil organisms, known as soil biota, plays a critical role in terrestrial ecosystems. Different ecosystems exhibit varied responses of soil organisms to soil physical and chemical properties (SPCPs). However, our understanding of how soil biota react to different soil depths in naturally established population of salinity tolerant Tamarix ramosissima in desert ecosystems, remains limited. To address this, we employed High-Throughput Illumina HiSeq Sequencing to examine the population dynamics of soil bacteria, fungi, archaea, protists, and metazoa at six different soil depths (0-100 cm) in the naturally occurring T. ramosissima dominant zone within the Taklimakan desert of China. Our observations reveal that the alpha diversity of bacteria, fungi, metazoa, and protists displayed a linear decrease with the increase of soil depth, whereas archaea exhibited an inverse pattern. The beta diversity of soil biota, particularly metazoa, bacteria, and protists, demonstrated noteworthy associations with soil depths through Non-Metric Dimensional Scaling analysis. Among the most abundant classes of soil organisms, we observed Actinobacteria, Sordariomycetes, Halobacteria, Spirotrichea, and Nematoda for bacteria, fungi, archaea, protists, and metazoa, respectively. Additionally, we identified associations between the vertical distribution of dominant biotic communities and SPCPs. Bacterial changes were mainly influenced by total potassium, available phosphorus (AP), and soil water content (SWC), while fungi were impacted by nitrate (NO3-) and available potassium (AK). Archaea showed correlations with total carbon (TC) and AK thus suggesting their role in methanogenesis and methane oxidation, protists with AP and SWC, and metazoa with AP and pH. These correlations underscore potential connections to nutrient cycling and the production and consumption of greenhouse gases (GhGs). This insight establishes a solid foundation for devising strategies to mitigate nutrient cycling and GHG emissions in desert soils, thereby playing a pivotal role in the advancement of comprehensive approaches to sustainable desert ecosystem management.


Assuntos
Ecossistema , Tamaricaceae , Solo/química , Conservação dos Recursos Naturais , Archaea/genética , Bactérias , Biota , Nutrientes , Fungos , Potássio , Microbiologia do Solo
8.
Chemosphere ; 352: 141411, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350515

RESUMO

As an emerging form of pollution, microplastic contamination of the coastal ecosystems is one of the world's most pressing environmental concerns. Coastal sediments have been polluted to varying degrees by microplastics, and their ubiquitous presence in sediments poses a threat to marine organisms. However, there is currently no ecological risk assessment of microplastics on aquatic biota in sediments. This study, for the first time, established a new procedure to evaluate the toxicity of microplastics on aquatic biota in sediments, based on the probabilistic risk assessment (PRA) concept. The choice of Zhelin Bay as the case study site was based on its severe pollution status. The average content of microplastics in the sediments of Zhelin Bay was 2054.17 items kg-1 dry weight, and these microplastics consisted of 46 different species. Microplastics in sediments exist in five different forms, with the film form being the main composition, and the majority of microplastics have particle sizes ranging from 100 to 500 µm. Correlation analysis (CA) reveals significant negative correlations between microplastic abundance, and Al2O3 and SiO2. The toxicity of microplastics, based on the PRA concept, suggests that Zhelin Bay surface sediments had a low probability (3.43%) of toxic effects on aquatic biota.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Ecossistema , Dióxido de Silício , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Biota , Medição de Risco , Sedimentos Geológicos
9.
PeerJ ; 12: e16664, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188173

RESUMO

Background: The niche conservatism hypothesis postulates that physiological and phylogenetic factors constrain species distributions, creating richness hotspots with older lineages in ancestral climatic conditions. Conversely, niche convergence occurs when species successfully disperse to novel environments, diversifying and resulting in areas with high phylogenetic clustering and endemism, low diversity, and lower clade age. The Mexican Transition Zone exhibits both patterns as its biotic assembly resulted from successive dispersal events of different biotic elements called cenocrons. We test the hypothesis that biogeographic transitionallity in the area is a product of niche conservatism in the Nearctic and Typical Neotropical cenocrons and niche convergence in the Mountain Mesoamerican cenocron. Methods: We split the avifauna into three species sets representing cenocrons (sets of taxa that share the same biogeographic history, constituting an identifiable subset within a biota by their common biotic origin and evolutionary history). Then, we correlated richness, endemism, phylogenetic diversity, number of nodes, and crowning age with environmental and topographic variables. These correlations were then compared with the predictions of niche conservatism versus niche convergence. We also detected areas of higher species density in environmental space and interpreted them as an environmental transition zone where birds' niches converge. Results: Our findings support the expected predictions on how niches evolved. Nearctic and Typical Neotropical species behaved as predicted by niche conservatism, whereas Mountain Mesoamerican species and the total of species correlations indicated niche convergence. We also detected distinct ecological and evolutionary characteristics of the cenocrons on a macroecological scale and the environmental conditions where the three cenocrons overlap in the Mesoamerican region.


Assuntos
Evolução Biológica , Biota , Animais , Filogenia , Aves
10.
Sci Rep ; 14(1): 103, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167527

RESUMO

Loki's Castle Vent Field (LCVF, 2300 m) was discovered in 2008 and represents the first black-smoker vent field discovered on the Arctic Mid-Ocean Ridge (AMOR). However, a comprehensive faunal inventory of the LCVF has not yet been published, hindering the inclusion of the Arctic in biogeographic analyses of vent fauna. There is an urgent need to understand the diversity, spatial distribution and ecosystem function of the biological communities along the AMOR, which will inform environmental impact assesments of future deep-sea mining activities in the region. Therefore, our aim with this paper is to provide a comprehensive inventory of the fauna at LCVF and present a first insight into the food web of the vent community. The fauna of LCVF has a high degree of novelty, with five new species previously described and another ten new species awaiting formal description. Most of the new species from LCVF are either hydrothermal vent specialists or have been reported from other chemosynthesis-based ecosystems. The highest taxon richness is found in the diffuse venting areas and may be promoted by the biogenic habitat generated by the foundation species Sclerolinum contortum. The isotopic signatures of the vent community of LCVF show a clear influence of chemosynthetic primary production on the foodweb. Considering the novel and specialised fauna documented in this paper, hydrothermal vents on the AMOR should be regarded as vulnerable marine ecosystems and protective measures must therefore be implemented, especially considering the potential threat from resource exploration and exploitation activities in the near future.


Assuntos
Ecossistema , Fontes Hidrotermais , Ecologia , Cadeia Alimentar , Biota , Oceanos e Mares
11.
Ecol Lett ; 27(1): e14358, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38288867

RESUMO

Beyond abiotic conditions, do population dynamics mostly depend on a species' direct predators, preys and conspecifics? Or can indirect feedback that ripples across the whole community be equally important? Determining where ecological communities sit on the spectrum between these two characterizations requires a metric able to capture the difference between them. Here we show that the spectral radius of a community's interaction matrix provides such a metric, thus a measure of ecological collectivity, which is accessible from imperfect knowledge of biotic interactions and related to observable signatures. This measure of collectivity integrates existing approaches to complexity, interaction structure and indirect interactions. Our work thus provides an original perspective on the question of to what degree communities are more than loose collections of species or simple interaction motifs and explains when pragmatic reductionist approaches ought to suffice or fail when applied to ecological communities.


Assuntos
Biota , Modelos Biológicos , Dinâmica Populacional , Ecossistema
12.
Glob Chang Biol ; 30(1): e17094, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273479

RESUMO

External nutrient loading can cause large changes in freshwater ecosystems. Many local field and laboratory experiments have investigated ecological responses to nutrient addition. However, these findings are difficult to generalize, as the responses observed may depend on the local context and the resulting nutrient concentrations in the receiving water bodies. In this research, we combined and analysed data from 131 experimental studies containing 3054 treatment-control abundance ratios to assess the responses of freshwater taxa along a gradient of elevated nutrient concentrations. We carried out a systematic literature search in order to identify studies that report the abundance of invertebrate, macrophyte, and fish taxa in relation to the addition of nitrogen, phosphorus, or both. Next, we established mixed-effect meta-regression models to relate the biotic responses to the concentration gradients of both nutrients. We quantified the responses based on various abundance-based metrics. We found no responses to the mere addition of nutrients, apart from an overall increase of total invertebrate abundance. However, when we considered the gradients of N and P enrichment, we found responses to both nutrients for all abundance metrics. Abundance tended to increase at low levels of N enrichment, yet decreased at the high end of the concentration gradient (1-10 mg/L, depending on the P concentration). Responses to increasing P concentrations were mostly positive. For fish, we found too few data to perform a meaningful analysis. The results of our research highlight the need to consider the level of nutrient enrichment rather than the mere addition of nutrients in order to better understand broad-scale responses of freshwater biota to eutrophication, as a key step to identify effective conservation strategies for freshwater ecosystems.


Assuntos
Ecossistema , Invertebrados , Animais , Água Doce , Biota , Peixes , Nutrientes/análise , Fósforo/análise , Nitrogênio/análise , Eutrofização
13.
Am Nat ; 203(1): 1-13, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207143

RESUMO

AbstractAverage concentrations of biota in the ocean are low, presenting a critical problem for ocean consumers. High-resolution sampling, however, demonstrates that the ocean is peppered with narrow hot spots of organism activity. To determine whether these resource aggregations could provide a significant solution to the ocean's food paradox, a conceptual graphical model was developed that facilitates comparisons of the role of patchiness in predator-prey interactions across taxa, size scales, and ecosystems. The model predicts that predators are more reliant on aggregated resources for foraging success when the average concentrations of resources is low, the size discrepancy between predator and prey is great, the predator has a high metabolic rate, and/or the predator's foraging time is limited. Size structure differences between marine and terrestrial food webs and a vast disparity in the overall mean density of their resources lead to the conclusion that high-density aggregations of prey are much more important to the survival of oceanic predators than their terrestrial counterparts, shaping the foraging decisions that are available to an individual and setting the stage on which evolutionary pressures can act. Patches of plenty may be rare, but they play an outsized role in behavioral, ecological, and evolutionary processes, particularly in the sea.


Assuntos
Ecossistema , Comportamento Predatório , Animais , Cadeia Alimentar , Oceanos e Mares , Biota
14.
Ecol Lett ; 27(1): e14360, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38183675

RESUMO

Communities worldwide are losing multiple species at an unprecedented rate, but how communities reassemble after these losses is often an open question. It is well established that the order and timing of species arrival during community assembly shapes forthcoming community composition and function. Yet, whether the order and timing of species losses can lead to divergent community trajectories remains largely unexplored. Here, we propose a novel framework that sets testable hypotheses on the effects of the order and timing of species losses-inverse priority effects-and suggests its integration into the study of community assembly. We propose that the order and timing of species losses within a community can generate alternative reassembly trajectories, and suggest mechanisms that may underlie these inverse priority effects. To formalize these concepts quantitatively, we used a three-species Lotka-Volterra competition model, enabling to investigate conditions in which the order of species losses can lead to divergent reassembly trajectories. The inverse priority effects framework proposed here promotes the systematic study of the dynamics of species losses from ecological communities, ultimately aimed to better understand community reassembly and guide management decisions in light of rapid global change.


Assuntos
Biota , Ecossistema
15.
Commun Biol ; 7(1): 103, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228754

RESUMO

Animal species, encompassing both pollinators and herbivores, exhibit a preference for plants based on optimal foraging theory. Understanding the intricacies of these adaptive plant-animal interactions in the context of community assembly poses a main challenge in ecology. This study delves into the impact of adaptive interaction rewiring between species belonging to different guilds on the structure and stability of a 3-guild ecological network, incorporating both mutualistic and antagonistic interactions. Our findings reveal that adaptive rewiring results in sub-networks becoming more nested and compartmentalized. Furthermore, the rewiring of interactions uncovers a positive correlation between a plant's generalism concerning both pollinators and herbivores. Additionally, there is a positive correlation between a plant's degree centrality and its energy budget. Although network stability does not exhibit a clear relationship with non-random structures, it is primarily influenced by the balance of multiple interaction strengths. In summary, our results underscore the significance of adaptive interaction rewiring in shaping the structure of 3-guild networks. They emphasize the importance of considering the balance of multiple interactions for the stability of adaptive networks, providing valuable insights into the complex dynamics of ecological communities.


Assuntos
Herbivoria , Polinização , Animais , Simbiose , Biota , Plantas
16.
PLoS Comput Biol ; 20(1): e1011770, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241353

RESUMO

Until recently, most ecological network analyses investigating the effects of species' declines and extinctions have focused on a single type of interaction (e.g. feeding). In nature, however, diverse interactions co-occur, each of them forming a layer of a 'multilayer' network. Data including information on multiple interaction types has recently started to emerge, giving us the opportunity to have a first glance at possible commonalities in the structure of these networks. We studied the structural features of 44 tripartite ecological networks from the literature, each composed of two layers of interactions (e.g. herbivory and pollination), and investigated their robustness to species losses. Considering two interactions simultaneously, we found that the robustness of the whole community is a combination of the robustness of the two ecological networks composing it. The way in which the layers of interactions are connected to each other affects the interdependence of their robustness. In many networks, this interdependence is low, suggesting that restoration efforts would not automatically propagate through the whole community. Our results highlight the importance of considering multiple interactions simultaneously to better gauge the robustness of ecological communities to species loss and to more reliably identify key species that are important for the persistence of ecological communities.


Assuntos
Biota , Polinização , Herbivoria , Ecossistema
17.
Mar Pollut Bull ; 199: 115978, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38217911

RESUMO

The detrimental effects of anthropogenic underwater noise on marine organisms have garnered significant attention among scientists. This review delves into the research concerning the repercussions of underwater noise on marine species, with specific emphasis on the physiological and molecular responses of marine biota. This review investigates the sensory mechanisms, hearing sensitivity, and reaction thresholds of diverse marine organisms, shedding light on their susceptibility to underwater noise disturbances. The physiological and molecular effects of anthropogenic underwater noise on marine biota include oxidative stress, energy homeostasis, metabolism, immune function, and respiration. Additionally, changes in the gene expression profile associated with oxidative stress, metabolism, and immunological response are among the responses reported for marine biota. These effects pose a threat to animal fitness and potentially affect their survival as individuals and populations.


Assuntos
Organismos Aquáticos , Ruído , Humanos , Animais , Organismos Aquáticos/fisiologia , Audição/fisiologia , Biota
18.
Mar Pollut Bull ; 199: 116005, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219292

RESUMO

This study examines the mercury content in the marine matrices water column, surface sediment and benthic invertebrates of Coronel and Coliumo bays, central Chile, under winter and summer conditions. Coronel Bay has been subject to intense industrialization in the last three decades, while Coliumo Bay remains as a fisherman's cove and a popular summer tourism destination. Our results reveal significantly higher mercury concentrations in the three environmental matrices analyzed for Coronel Bay, while Coliumo Bay exhibits levels within the range considered natural. Moreover, the mercury levels in Coronel Bay exceed the optimal criteria for aquatic life, indicating a deterioration in environmental quality of this locality. Industrial development is identified as main factor explaining the differences observed between these two coastal water bodies. This study presents the most updated record of mercury levels in the Southeast Pacific and represents the first comprehensive evaluation of marine environmental matrices in two bays with divergent activities.


Assuntos
Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Chile , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água do Mar , Água , Biota , Baías , Sedimentos Geológicos
19.
J Hazard Mater ; 465: 133520, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38232553

RESUMO

Assessing the ecological risks of microplastics is difficult because of the limited availability of reliable ecotoxicity data. Although freshwater is a valuable sink for microplastics, the current framework for ecological risk assessment using traditional toxicity data is not applicable to freshwater ecosystems. Herein, species sensitivity distribution (SSD) curves were compared for edible and all microplastics exposed to aquatic organisms based on traditional endpoint-based and all-endpoint-based databases. Freshwater toxicity data for microplastics were screened after verifying microplastic presence in test species (56 toxicity datapoints for one microalga, three water fleas, one fish, and one crab; 0.02-100 µm-sized microplastics). SSD and curve parameters were compared with or without non-traditional toxicity endpoints. The HC50 in all endpoint databases was more sensitive than that in the traditional endpoint database and showed a good fit. SSD curves derived from the database for all microplastics were compared and analyzed with edible microplastics. HCx increased for edible microplastics (0.02-100 µm-sized) than for all microplastics (0.02-200 µm-sized), and the size of edible microplastics was lower than of all microplastics. Thus, using non-traditional toxicity data, the SSD approach compensates for the limited ecotoxicity data on microplastics while considering the internalization of microplastics in biota.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Plásticos , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água Doce , Biota
20.
Chemosphere ; 351: 141201, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246502

RESUMO

This study explores the accumulation of total mercury (THg) in deep-sea sediments and demersal megafauna of the ultra-oligotrophic Southeastern Mediterranean Sea (SEMS) across bathymetric gradients in the range 35-1900 m, sampled in seven cruises during 2013, 2017-2021, and 2023. Measurements of THg were conducted in surficial (0.0-0.5 cm) and subsurface (9.0-10 cm) sediments, demersal sharks, demersal teleost fish, and benthic crustaceans. Sedimentary organic carbon and biota δ13C and δ15N values were determined to explore possible foraging habitats and dietary sources of THg. The results exhibit an increasing trend of THg in surficial sediments with increasing bottom depth, while in the subsurface, pre-industrial sediments, THg remains lower, slightly increasing with depth. Having no major terrestrial point sources in this area, this increasing trend of THg in surficial sediments across bathymetric gradients is controlled by atmospheric mercury deposition, scavenged by the biological pump, and by lateral transport of particulate Hg in winnowed fine particles from the shelf. Similarly, the THg in benthic crustaceans and demersal fish ranged between 0.02 and 2.71 µg g-1 wet weight (0.06 and 10.8 µg g-1 dry weight) and increased with muscle δ13C as a function of distance offshore, while presenting a low THg-δ15N bio-magnification power. Our results suggest that foraging habitats, longevity, and species-specific depth distribution control their muscle THg bioaccumulation. Despite this complexity, the pooling of THg in megafauna into specific deep zones reflected the trend of increasing anthropogenic THg across bathymetric gradients. Furthermore, many of the biota measurements exceeded safe consumption thresholds for Hg and therefore, should be considered carefully in the development and regulation of deep-sea trawling in this region.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Mar Mediterrâneo , Ecossistema , Biota , Músculos/química , Peixes , Crustáceos , Poluentes Químicos da Água/análise , Monitoramento Ambiental
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