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1.
Ecol Evol ; 14(11): e70470, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39493613

RESUMO

The microfossil record contains abundant, diverse, and well-preserved fossils spanning multiple trophic levels from primary producers to apex predators. In addition, microfossils often constitute and are preserved in high abundances alongside continuous high-resolution geochemical proxy records. These characteristics mean that microfossils can provide valuable context for understanding the modern climate and biodiversity crises by allowing for the interrogation of spatiotemporal scales well beyond what is available in neo-ecological research. Here, we formalize a research framework of "micropaleoecology," which builds on a holistic understanding of global change from the environment to ecosystem level. Location: Global. Time period: Neoproterozoic-Phanerozoic. Taxa studied: Fossilizing organisms/molecules. Our framework seeks to integrate geochemical proxy records with microfossil records and metrics, and draws on mechanistic models and systems-level statistical analyses to integrate disparate records. Using multiple proxies and mechanistic mathematical frameworks extends analysis beyond traditional correlation-based studies of paleoecological associations and builds a greater understanding of past ecosystem dynamics. The goal of micropaleoecology is to investigate how environmental changes impact the component and emergent properties of ecosystems through the integration of multi-trophic level body fossil records (primarily using microfossils, and incorporating additional macrofossil data where possible) with contemporaneous environmental (biogeochemical, geochemical, and sedimentological) records. Micropaleoecology, with its focus on integrating ecological metrics within the context of paleontological records, facilitates a deeper understanding of the response of ecosystems across time and space to better prepare for a future Earth under threat from anthropogenic climate change.

2.
Mar Environ Res ; 202: 106803, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39432955

RESUMO

Changes in oceanographic conditions can affect species distribution in marine habitats. Global climate change may negatively influence the oceanographic factor-species distribution relationship. Here, we assessed the influence of oceanographic conditions on chub mackerel (Scomber japonicus) distribution in northeastern Taiwan by constructing and using a habitat ensemble model incorporating chub mackerel fishery, climatic oscillation, and oceanography data. Our results indicated that the chub mackerel catch was mainly influenced by the Western Pacific Oscillation. Moreover, sea-surface height and mixed-layer depth exerted the most and least significant effects on chub mackerel distribution, respectively. The chub mackerel catch rate peaked in the study area with a sea-surface temperature of 29 °C, sea-surface chlorophyll of 0.25 mg/m3, sea-surface salinity of 33.7 psµ, and SSH of 0.575 m. Chub mackerel was the most widely distributed in the area between 25°N, 120.5°E and 26.2°N, 121.5°E. Our findings can be used to develop critical adaptation plans for managing chub mackerel fisheries in the northeastern waters of Taiwan. Considering changing climate conditions globally, the incorporation of this knowledge into managerial strategies may aid decision-makers in protecting not only other ocean fisheries but also individuals dependent on them.

3.
iScience ; 27(10): 111034, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39474063

RESUMO

We use molecular analyses, color patterns, and records of distribution of mating pairs to reconstruct the global phylogeography of Alpheus lottini, a complex of cryptic coral-associated snapping shrimp species. Molecular data support the delineation of ancestral clades A, B, and C, and suggest five additional subdivisions within clades A and B. Clades A, B1, B2, and C exhibit color pattern differences and/or evidence of assortative mating, and thus merit species-level recognition. There is no evidence for assortative mating within clades A and B1, with likely reproductive compatibility (i.e., fertile clutches) in areas of sympatry. The clade diversity peaks in the Mariana Islands and the early branching clade C is restricted to the northern periphery of the Central and Western Pacific suggesting a Pacific origin of this group outside of the Coral Triangle. These findings underscore the prevalence of allopatric processes with possible ecological or microallopatric speciation in areas where clades overlap.

4.
Mar Pollut Bull ; 209(Pt A): 117154, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39471721

RESUMO

Coral reefs are maintained by a balance between formation (calcifiers) and destructive processes (dissolution and erosion). In eastern tropical Pacific reefs, Porites genus is the second-largest contributor to CaCO3 production, but is affected by bioerosion. In this study, we evaluate the interaction between Lithophaga and Porites in an island reef in the Mexican Pacific by quantifying bioerosion rate, its impact on CaCO3 production, and contrasting growth models. To achieve this, Porites lobata colonies were collected to evaluate calcification and CaCO3 production. Shells of Lithophaga (Leiosolenus plumula) were extracted from corals, and age and length fed into a growth model. Our results indicate a high bioerosion rate (21.9 ± 4.1 %), representing 8.3 % of overall CaCO3 production. Bivalves' age (8 y) was less than corals (12.6 y), and cohort analysis indicates an intense recruitment. We associate this with high productivity derived from the island's oceanography, promoting nutrient enrichment, a plausible scenario for reefs under eutrophication conditions.

5.
Adv Mar Biol ; 97: 191-215, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39307558

RESUMO

Marine space is three dimensional, the turnover of life forms is rapid, defining a fourth dimension: time. The definition of ecologically significant spatial units calls for the spatio-temporal framing of significant ecological connections in terms of extra-specific (biogeochemical cycles), intra-specific (life cycles), and inter-specific (food webs) fluxes. The oceanic volume can be split in sub-systems that can be further divided into smaller sub-units where ecosystem processes are highly integrated. The volumes where oceanographic and ecological processes take place are splittable into hot spots of ecosystem functioning, e.g., upwelling currents triggering plankton blooms, whose products are then distributed by horizontal currents, so defining Cells of Ecosystem Functioning (CEFs), whose identification requires the collaboration of physical and chemical oceanography, biogeochemistry, marine geology, plankton, nekton and benthos ecology and biology, food web dynamics, marine biogeography. CEFs are fuzzy objects that reflect the instability of marine systems.


Assuntos
Ecossistema , Oceanos e Mares , Organismos Aquáticos/fisiologia , Cadeia Alimentar , Animais
6.
iScience ; 27(9): 110838, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39318536

RESUMO

A recurring trend in evidence scrutinized over the past few decades is that disease outbreaks will become more frequent, intense, and widespread on land and in water, due to climate change. Pathogens and the diseases they inflict represent a major constraint on seafood production and yield, and by extension, food security. The risk(s) for fish and shellfish from disease is a function of pathogen characteristics, biological species identity, and the ambient environmental conditions. A changing climate can adversely influence the host and environment, while augmenting pathogen characteristics simultaneously, thereby favoring disease outbreaks. Herein, we use a series of case studies covering some of the world's most cultured aquatic species (e.g., salmonids, penaeid shrimp, and oysters), and the pathogens (viral, fungal, bacterial, and parasitic) that afflict them, to illustrate the magnitude of disease-related problems linked to climate change.

7.
Commun Earth Environ ; 5(1): 480, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39239114

RESUMO

Although internal seiches are ubiquitous in large, deep lakes, little is known about the effect of higher vertical-mode seiches on deepwater dynamics. Here, by combining entire summer season current and temperature observations and 3D numerical modeling, we demonstrate that previously undetected vertical mode-two and mode-three Poincaré waves in 309-meter deep Lake Geneva (Switzerland/France) generate bottom-boundary layer currents up to 4 cm s-1. Poincaré wave amphidromic patterns revealed three strong cells excited simultaneously. Weak hypolimnetic stratification (N 2 ≈ 10-6 s -2), typical of deep lakes, significantly modified the wave structure by shifting the lower vertical node in the lake's center from ~75-meter depth (without stratification) to ~150-meter depth (with stratification). This shift induces shear in the middle of the hypolimnion and strengthens bottom currents, with important implications for hypolimnetic mixing and sediment-water exchange. Our findings demonstrate that classical concepts based on constant temperature layers cannot correctly characterize higher vertical-mode Poincaré seiches in deep lakes.

8.
Data Brief ; 55: 110728, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39113788

RESUMO

The U.S. Gulf of Mexico contains a complex network of existing, decommissioned, and abandoned oil and gas pipelines, which are susceptible to a number of stressors in the natural-engineered offshore system including corrosion, environmental hazards, and human error. The age of these structures, coupled with extreme weather events increasing in intensity and occurrence from climate change, have resulted in detrimental environmental and operational impacts such as hydrocarbon release events and pipeline damage. To support the evaluation of pipeline infrastructure integrity for reusability, remediation, and risk prevention, the U.S. Gulf of Mexico Pipeline and Reported Incident Datasets were developed and published. These datasets, in addition to supporting advanced analytics, were constructed to inform regulatory, industry, and research stakeholders. They encompass more than 490 attributes relating to structural information, incident reports, environmental loading statistics, seafloor factors, and potential geohazards, all of which have been spatially, and in some cases temporally matched to more than 89,000 oil and gas pipeline locations. Attributes were acquired or derived from publicly available, credible resources, and were processed using a combination of manual efforts and customized scripts, including big data processing using supercomputing resources. The resulting datasets comprise a spatial geodatabase, tabular files, and metadata. These datasets are publicly available through the Energy Data eXchange®, a curated online data and research library and laboratory developed by the U.S. Department of Energy's National Energy Technology Laboratory. This article describes the contents of the datasets, details the methods involved in processing and curation, and suggests application of the data to inform and mitigate risk associated with offshore pipeline infrastructure in the Gulf of Mexico.

9.
ISME Commun ; 4(1): ycae090, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39165394

RESUMO

Passive sinking flux of particulate organic matter in the ocean plays a central role in the biological carbon pump and carbon export to the ocean's interior. Particle-associated microbes colonize particulate organic matter, producing "hotspots" of microbial activity. We evaluated variation in particle-associated microbial communities to 500 m depth across four different particle size fractions (0.2-1.2, 1.2-5, 5-20, >20 µm) collected using in situ pumps at the Bermuda Atlantic Time-series Study site. In situ pump collections capture both sinking and suspended particles, complementing previous studies using sediment or gel traps, which capture only sinking particles. Additionally, the diagenetic state of size-fractionated particles was examined using isotopic signatures alongside microbial analysis. Our findings emphasize that different particle sizes contain distinctive microbial communities, and each size category experiences a similar degree of change in communities over depth, contradicting previous findings. The robust patterns observed in this study suggest that particle residence times may be long relative to microbial succession rates, indicating that many of the particles collected in this study may be slow sinking or neutrally buoyant. Alternatively, rapid community succession on sinking particles could explain the change between depths. Complementary isotopic analysis of particles revealed significant differences in composition between particles of different sizes and depths, indicative of organic particle transformation by microbial hydrolysis and metazoan grazing. Our results couple observed patterns in microbial communities with the diagenetic state of associated organic matter and highlight unique successional patterns in varying particle sizes across depth.

10.
Ecology ; 105(10): e4412, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39193809

RESUMO

Patterns of population connectivity shape ecological and evolutionary phenomena from population persistence to local adaptation and can inform conservation strategy. Connectivity patterns emerge from the interaction of individual behavior with a complex and heterogeneous environment. Despite ample observation that dispersal patterns vary through time, the extent to which variation in the physical environment can explain emergent connectivity variation is not clear. Empirical studies of its contribution promise to illuminate a potential source of variability that shapes the dynamics of natural populations. We leveraged simultaneous direct dispersal observations and oceanographic transport simulations of the clownfish Amphiprion clarkii in the Camotes Sea, Philippines, to assess the contribution of oceanographic variability to emergent variation in connectivity. We found that time-varying oceanographic simulations on both annual and monsoonal timescales partly explained the observed dispersal patterns, suggesting that temporal variation in oceanographic transport shapes connectivity variation on these timescales. However, interannual variation in observed mean dispersal distance was nearly 10 times the expected variation from biophysical simulations, revealing that additional biotic and abiotic factors contribute to interannual connectivity variation. Simulated dispersal kernels also predicted a smaller scale of dispersal than the observations, supporting the hypothesis that undocumented abiotic factors and behaviors such as swimming and navigation enhance the probability of successful dispersal away from, as opposed to retention near, natal sites. Our findings highlight the potential for coincident observations and biophysical simulations to test dispersal hypotheses and the influence of temporal variability on metapopulation persistence, local adaptation, and other population processes.


Assuntos
Larva , Modelos Biológicos , Oceanos e Mares , Animais , Larva/fisiologia , Fatores de Tempo , Distribuição Animal , Simulação por Computador , Oceanografia , Ecossistema , Perciformes/fisiologia , Demografia
11.
iScience ; 27(7): 110236, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39015147

RESUMO

The reduction in sea ice cover with Arctic warming facilitates shipping through remarkably shorter shipping routes. Automatic identification system (AIS) is a powerful data source to monitor Arctic Ocean shipping. Based on the AIS data from an online platform, we quantified the spatial distribution of shipping through this area, its intensity, and the seasonal variation. Shipping was heterogeneously distributed with power-law exponents that depended on the vessel category. We contextualized the estimated exponents with the analytical distribution of a transit model in one and two dimensions. Fishing vessels had the largest spatial spread, while narrower shipping routes associated with cargo and tanker vessels had a width correlated with the sea ice area. The time evolution of these routes showed extended periods of shipping activity through the year. We used AIS data to quantify recent Arctic shipping, which brings an opportunity for shorter routes, but likely impacting the Arctic ecosystem.

12.
Toxins (Basel) ; 16(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38922174

RESUMO

Despite the fact that the first red tide reported on the coasts of the Iberian Peninsula was due to Lingulodinium polyedra, knowledge about their frequency and, particularly, about the environmental conditions contributing to bloom initiation is still scarce. For this reason, L. polyedra bloom episodes were observed and studied in three Galician rias during the summer season based on the 1993-2008 record database period; additionally, samples were collected in summer 2008. Proliferations of L. polyedra occurred in the rias of Ares and Barqueiro in June and August, respectively, while in the Ria of Coruña, they persisted from the end of June to early September. Red tides developed when the surface temperature reached 17 °C, with "seasonal thermal window" conditions, and when salinities were ≥30, i.e., an "optimal salinity window"; when these parameters were lower than these thresholds, cyst germination decreased. A cyst transport mechanism from sediments to the surface must also exist; this mechanism was found to be natural (tidal currents) in the ria of Barqueiro or anthropogenic (dredging) in the rias of Ares and Coruña. Surface temperatures during summer were usually favorable for cyst germination (85 to 100%) during the 1993-2008 period; however, water temperatures below 10 m depth only rarely reached the 17 °C threshold (2 to 18%). During this 16-year period, dredging activities could explain 71% (Coruña) and 44% (Ares) of the recorded bloom events. When a bloom episode developed in early summer, favorable conditions did not lead to a new red tide, probably due to the lag period required by cysts for germination. Moreover, blooms did not develop when high densities of diatoms (>1,000,000 cells·L-1) remained in the water column as a result of summer upwelling pulses occurring in specific years. The temperature-sediment disturbance pattern found in this study provides a useful tool for the prevention of eventual risks resulting from red tides of this dinoflagellate.


Assuntos
Dinoflagellida , Proliferação Nociva de Algas , Temperatura , Dinoflagellida/crescimento & desenvolvimento , Espanha , Estações do Ano , Monitoramento Ambiental , Água do Mar , Sedimentos Geológicos , Salinidade
13.
Proc Natl Acad Sci U S A ; 121(19): e2319937121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38696469

RESUMO

Subtropical oceans contribute significantly to global primary production, but the fate of the picophytoplankton that dominate in these low-nutrient regions is poorly understood. Working in the subtropical Mediterranean, we demonstrate that subduction of water at ocean fronts generates 3D intrusions with uncharacteristically high carbon, chlorophyll, and oxygen that extend below the sunlit photic zone into the dark ocean. These contain fresh picophytoplankton assemblages that resemble the photic-zone regions where the water originated. Intrusions propagate depth-dependent seasonal variations in microbial assemblages into the ocean interior. Strikingly, the intrusions included dominant biomass contributions from nonphotosynthetic bacteria and enrichment of enigmatic heterotrophic bacterial lineages. Thus, the intrusions not only deliver material that differs in composition and nutritional character from sinking detrital particles, but also drive shifts in bacterial community composition, organic matter processing, and interactions between surface and deep communities. Modeling efforts paired with global observations demonstrate that subduction can flux similar magnitudes of particulate organic carbon as sinking export, but is not accounted for in current export estimates and carbon cycle models. Intrusions formed by subduction are a particularly important mechanism for enhancing connectivity between surface and upper mesopelagic ecosystems in stratified subtropical ocean environments that are expanding due to the warming climate.


Assuntos
Bactérias , Oceanos e Mares , Água do Mar , Água do Mar/microbiologia , Água do Mar/química , Bactérias/metabolismo , Carbono/metabolismo , Ciclo do Carbono , Clorofila/metabolismo , Ecossistema , Fitoplâncton/metabolismo , Estações do Ano , Biomassa , Microbiota/fisiologia , Oxigênio/metabolismo
14.
Environ Monit Assess ; 196(5): 415, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568381

RESUMO

In this study, we used a comprehensive array of sampling techniques to examine the pollution caused by organic micropollutants in Izmit Bay for the first time. Our methodology contains spot seawater sampling, semi-permeable membrane devices (SPMDs) passive samplers for time-weighted average (TWA), and sediment sampling for long-term pollution detection in Izmit Bay, together. Additionally, the analysis results obtained with these three sampling methods were compared in this study. Over the course of two seasons in 2020 and 2021, we deployed SPMDs for 21 days in the first season and for 30 days in the second season. This innovative approach allowed us to gather sea water samples and analyze them for the presence of polycyclic aromatic hydrocarbons (Σ15 PAHs), polychlorinated biphenyls (Σ7 PCBs), and organochlorine pesticides (Σ11 OCPs). Using SPMD-based passive sampling, we measured micropollutant concentrations: PAHs ranged from 1963 to 10342 pg/L in 2020 and 1338 to 6373 pg/L in 2021; PCBs from 17.46 to 61.90 pg/L in 2020 and 8.37 to 78.10 pg/L in 2021; and OCPs from 269.2 to 8868 pg/L in 2020 and 141.7 to 1662 pg/L in 2021. Our findings revealed parallels between the concentrations of PAHs, PCBs, and OCPs in both SPMDs and sediment samples, providing insights into the distribution patterns of these pollutants in the marine ecosystem. However, it is worth noting that due to limited data acquisition, the suitability of spot sampling in comparison to instantaneous sampling remains inconclusive, highlighting the need for further investigation and data collection.


Assuntos
Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Baías , Ecossistema , Monitoramento Ambiental , Poluição Ambiental
15.
iScience ; 27(4): 109564, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38617563

RESUMO

The successful commercialization of algal biophotovoltaics (BPV) technology hinges upon a multifaceted approach, encompassing factors such as the development of a cost-efficient and highly conductive anode material. To address this issue, we developed an environmentally benign method of producing reduced graphene oxide (rGO), using concentrated Chlorella sp. UMACC 313 suspensions as the reducing agent. The produced rGO was subsequently coated on the carbon paper (rGO-CP) and used as the BPV device's anode. As a result, maximum power density was increased by 950% for Chlorella sp. UMACC 258 (0.210 mW m-2) and 781% for Synechococcus sp. UMACC 371 (0.555 mW m-2) compared to bare CP. The improved microalgae adhesion to the anode and improved electrical conductivity of rGO brought on by the effective removal of oxygen functional groups may be the causes of this. This study has demonstrated how microalgal-reduced GO may improve the efficiency of algal BPV for producing bioelectricity.

16.
mSystems ; 9(3): e0130623, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38411098

RESUMO

The continental shelf of the Western Antarctic Peninsula (WAP) is a highly variable system characterized by strong cross-shelf gradients, rapid regional change, and large blooms of phytoplankton, notably diatoms. Rapid environmental changes coincide with shifts in plankton community composition and productivity, food web dynamics, and biogeochemistry. Despite the progress in identifying important environmental factors influencing plankton community composition in the WAP, the molecular basis for their survival in this oceanic region, as well as variations in species abundance, metabolism, and distribution, remains largely unresolved. Across a gradient of physicochemical parameters, we analyzed the metabolic profiles of phytoplankton as assessed through metatranscriptomic sequencing. Distinct phytoplankton communities and metabolisms closely mirrored the strong gradients in oceanographic parameters that existed from coastal to offshore regions. Diatoms were abundant in coastal, southern regions, where colder and fresher waters were conducive to a bloom of the centric diatom, Actinocyclus. Members of this genus invested heavily in growth and energy production; carbohydrate, amino acid, and nucleotide biosynthesis pathways; and coping with oxidative stress, resulting in uniquely expressed metabolic profiles compared to other diatoms. We observed strong molecular evidence for iron limitation in shelf and slope regions of the WAP, where diatoms in these regions employed iron-starvation induced proteins, a geranylgeranyl reductase, aquaporins, and urease, among other strategies, while limiting the use of iron-containing proteins. The metatranscriptomic survey performed here reveals functional differences in diatom communities and provides further insight into the environmental factors influencing the growth of diatoms and their predicted response to changes in ocean conditions. IMPORTANCE: In the Southern Ocean, phytoplankton must cope with harsh environmental conditions such as low light and growth-limiting concentrations of the micronutrient iron. Using metratranscriptomics, we assessed the influence of oceanographic variables on the diversity of the phytoplankton community composition and on the metabolic strategies of diatoms along the Western Antarctic Peninsula, a region undergoing rapid climate change. We found that cross-shelf differences in oceanographic parameters such as temperature and variable nutrient concentrations account for most of the differences in phytoplankton community composition and metabolism. We opportunistically characterized the metabolic underpinnings of a large bloom of the centric diatom Actinocyclus in coastal waters of the WAP. Our results indicate that physicochemical differences from onshore to offshore are stronger than between southern and northern regions of the WAP; however, these trends could change in the future, resulting in poleward shifts in functional differences in diatom communities and phytoplankton blooms.


Assuntos
Diatomáceas , Diatomáceas/genética , Regiões Antárticas , Fitoplâncton/genética , Oceanos e Mares , Plâncton/metabolismo , Ferro/metabolismo
17.
Mov Ecol ; 12(1): 10, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297368

RESUMO

BACKGROUND: Measuring coastal-pelagic prey fields at scales relevant to the movements of marine predators is challenging due to the dynamic and ephemeral nature of these environments. Whale sharks (Rhincodon typus) are thought to aggregate in nearshore tropical waters due to seasonally enhanced foraging opportunities. This implies that the three-dimensional movements of these animals may be associated with bio-physical properties that enhance prey availability. To date, few studies have tested this hypothesis. METHODS: Here, we conducted ship-based acoustic surveys, net tows and water column profiling (salinity, temperature, chlorophyll fluorescence) to determine the volumetric density, distribution and community composition of mesozooplankton (predominantly euphausiids and copepods) and oceanographic properties of the water column in the vicinity of whale sharks that were tracked simultaneously using satellite-linked tags at Ningaloo Reef, Western Australia. Generalised linear mixed effect models were used to explore relationships between the 3-dimensional movement behaviours of tracked sharks and surrounding prey fields at a spatial scale of ~ 1 km. RESULTS: We identified prey density as a significant driver of horizontal space use, with sharks occupying areas along the reef edge where densities were highest. These areas were characterised by complex bathymetry such as reef gutters and pinnacles. Temperature and salinity profiles revealed a well-mixed water column above the height of the bathymetry (top 40 m of the water column). Regions of stronger stratification were associated with reef gutters and pinnacles that concentrated prey near the seabed, and entrained productivity at local scales (~ 1 km). We found no quantitative relationship between the depth use of sharks and vertical distributions of horizontally averaged prey density. Whale sharks repeatedly dove to depths where spatially averaged prey concentration was highest but did not extend the time spent at these depth layers. CONCLUSIONS: Our work reveals previously unrecognized complexity in interactions between whale sharks and their zooplankton prey.

18.
iScience ; 27(1): 108585, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38161413

RESUMO

Over the past few decades, Indonesia's marine conservation governance has been criticized. This article analyzes the overlaps and gaps in domestic law and policy regimes for cetaceans or marine mammal management and examines issues of institutional arrangements and legal frameworks related to cetacean conservation in Indonesia. The legal framework's progress on cetacean governance shows three distinct phases: 1975-1985 (species-focused governance approach), 1990-2009 (area-based approach), and 2010-present (broader marine governance approach). This study reveals that the main shortcoming of the legal framework is unclear mandates and overlapping jurisdictions. This study suggests several urgent policies that should be accommodated in the current legal regime to strengthen cetacean conservation. In addition, this research also recommends creating a collaboration mechanism between institutions and encouraging Indonesia to join as a full member of the International Whaling Commission and the Conservation of Migratory Species of Wild Animals Convention to strengthen cetacean governance and conservation.

19.
Ann Rev Mar Sci ; 16: 25-53, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37669566

RESUMO

In the outer solar system, a growing number of giant planet satellites are now known to be abodes for global oceans hidden below an outer layer of ice. These planetary oceans are a natural laboratory for studying physical oceanographic processes in settings that challenge traditional assumptions made for Earth's oceans. While some driving mechanisms are common to both systems, such as buoyancy-driven flows and tides, others, such as libration, precession, and electromagnetic pumping, are likely more significant for moons in orbit around a host planet. Here, we review these mechanisms and how they may operate across the solar system, including their implications for ice-ocean interactions. Future studies should continue to advance our understanding of each of these processes as well as how they may act together in concert. This interplay also has strong implications for habitability as well as testing oceanic hypotheses with future missions.


Assuntos
Camada de Gelo , Lua , Oceanografia
20.
Data Brief ; 52: 109828, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38105904

RESUMO

Coastal observations along the Texas coast are valuable for many stakeholders in diverse domains. However, the management of the collected data has been limited, creating gaps in hydrological and atmospheric datasets. Among these, water and air temperature measurements are particularly crucial for water temperature predictions, especially during freeze events. These events can pose a serious threat to endangered sea turtles and economically valuable fish, which can succumb to hypothermic stunning, making them vulnerable to cold-related illness or death. Reliable and complete water and air temperature measurements are needed to provide accurate predictions of when cold-stunning events occur. To address these concerns, the focus of this paper is to describe the method used to create a complete 10-year dataset that is representative of the upper Laguna Madre, TX using multiple stations and various gap-filling methods. The raw datasets consist of a decade's worth of air and water temperature measurements within the Upper Laguna Madre from 2012 to 2022 extracted from the archives of the Texas Coastal Ocean Observation Network and the National Park Service. Large portions of data from the multiple stations were missing from the raw datasets, therefore a systematic gap-filling approach was designed and applied to create a near-continuous dataset. The proposed imputation method consists of three steps, starting with a short gap interpolation method, followed by a long gap-filling process using nearby stations, and finalized by a second short gap interpolation method. This systematic data imputation approach was evaluated by creating random artificial gaps within the original datasets, filling them using the proposed data imputation method, and assessing the viability of the proposed methods using various performance metrics. The evaluation results help to ensure the reliability of the newly imputed dataset and the effectiveness of the data imputation method. The newly created dataset is a valuable resource that transcends the local cold-stunning issue, offering viable utility for analyzing temporal variability of air and water temperatures, exploring temperature interdependencies, reducing forecasting uncertainties, and refining natural resource and weather advisory decision-making processes. The cleaned dataset with minimal gaps (<2%) is ready and convenient for artificial intelligence and machine learning applications.

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