Spatial Abundance Research Articles

The Use of Image‐Based Data and Abundance Modelling Approaches for Predicting the Location of Vulnerable Marine Ecosystems in the South Pacific Ocean

ABSTRACTVulnerable marine ecosystems (VMEs) are typically fragile and slow to recover, thereby making them susceptible to disturbance, including fishing. In the high seas, the United Nations General Assembly (UNGA) requested regional fishery management organisations (RFMOs) to implement measures to prevent significant adverse impacts on VMEs. Here, we predict spatial abundances of 15 taxa, 13 VME indicator taxa, in the South Pacific RFMO (SPRFMO) area. Models used seafloor imagery data, an important advance on previously developed presence‐only predictions, to provide information on spatial variation in taxa abundance that is crucial for better inferring likely location of VMEs, rather than just distribution of VME indicator taxa. Abundance models varied in predictive power (mean R2 ranged 0.02–0.40). Uncertainty estimates of model predictions were developed to inform future spatial planning processes for conservation and management of VMEs. Using the VME index concept, abundance model outputs and previously published presence‐only model predictions were weighted using vulnerability scores, to explore how modelled outputs could provide spatial estimates of likely VME distribution. Spatial predictions of abundance improved on previous modelling to provide an almost complete suite of abundance models for VME indicator taxa in the western portion of the SPRFMO Convention area. Nevertheless, to improve utility of modelled outputs, we recommend more high‐quality seafloor imagery data be gathered within the SPRFMO Convention area to (1) validate abundance models developed here with independent data from the model area, (2) update models, if necessary, (3) link abundance information to ecosystem function and (4) explore validity of the adapted VME index approach used here.

Single-colony MALDI mass spectrometry imaging reveals spatial differences in metabolite abundance between natural and cultured Trichodesmium morphotypes.

Trichodesmium, a globally significant N2-fixing marine cyanobacterium, forms extensive surface blooms in nutrient-poor ocean regions. These blooms consist of a dynamic assemblage of Trichodesmium species that form distinct colony morphotypes and are inhabited by diverse microorganisms. Trichodesmium colony morphotypes vary in ecological niche, nutrient uptake, and organic molecule release, differentially impacting ocean carbon and nitrogen biogeochemical cycles. Here, we assessed the poorly studied spatial abundance of metabolites within and between three morphologically distinct Trichodesmium colonies collected from the Red Sea. We also compared these results with two morphotypes of the cultivable Trichodesmium strain IMS101. Using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) coupled with liquid extraction surface analysis (LESA) tandem mass spectrometry (MS2), we identified and localized a wide range of small metabolites associated with single-colony Trichodesmium morphotypes. Our untargeted MALDI-MSI approach revealed 80 unique features (metabolites) shared between Trichodesmium morphotypes. Discrimination analysis showed spatial variations in 57 shared metabolites, accounting for 62% of the observed variation between morphotypes. The greatest variations in metabolite abundance were observed between the cultured morphotypes compared to the natural colony morphotypes, suggesting substantial differences in metabolite production between the cultivable strain IMS101 and the naturally occurring colony morphotypes that the cultivable strain is meant to represent. This study highlights the variations in metabolite abundance between natural and cultured Trichodesmium morphotypes and provides valuable insights into metabolites common to morphologically distinct Trichodesmium colonies, offering a foundation for future targeted metabolomic investigations.IMPORTANCEThis work demonstrates that the application of spatial mass spectrometry imaging at single-colony resolution can successfully resolve metabolite differences between natural and cultured Trichodesmium morphotypes, shedding light on their distinct biochemical profiles. Understanding the morphological differences between Trichodesmium colonies is crucial because they impact nutrient uptake, organic molecule production, and carbon and nitrogen export, and subsequently influence ocean biogeochemical cycles. As such, our study serves as an important initial assessment of metabolite differences between distinct Trichodesmium colony types, identifying features that can serve as ideal candidates for future targeted metabolomic studies.

In Vitro Analysis of Aerodynamic Properties and Co-Deposition of a Fixed-Dose Combination of Fluticasone Furoate, Umeclidinium Bromide, and Vilanterol Trifenatate.

Effective airway delivery of a fixed-dose combination of triple-aerosolized inhaled corticosteroid (ICS)/long-acting beta agonist (LABA)/long-acting muscarinic antagonist (LAMA) is likely to positively affect therapeutic responses predicted in patients with asthma and chronic obstructive pulmonary disease. This study aimed to conduct in vitro fluticasone furoate, vilanterol trifenatate, and umeclidinium bromide depositions in a Next Generation Impactor. The aerodynamic properties of these inhaled medications influence the spatial distribution and drug abundance, particularly in the smaller airways, to reverse or alleviate disease pathology. The Next Generation Impactor was used to demonstrate the aerodynamic particle size distributions of fluticasone furoate, vilanterol trifenatate, and umeclidinium bromide delivered from a dry powder inhaler at different flow rates across all stages of the impactors. This in vitro study analyzed the distribution pattern of individual drug components to simulate mono-component deposition and co-deposition in the official model in the United States Pharmacopeia. An Andersen cascade impactor together with scanning electron microscope-energy-dispersive X-ray was employed to observe the drug deposition on each stage of the impactor. We found that the distribution pattern of each component at the same cascade level was comparable, and the aerosol particles of the three drugs reached the in vitro representation of the lower airway compartment. The specified flow rates generated the desired fine particle fraction, fine particle dose, and mass median aerodynamic diameter. Our results also demonstrated visualized deposition patterns of the delivered drugs from different stages of the cascade impactor that may predict deposition as it occurs in vivo. Spatial distribution and abundance of ICS/LABA/LAMA in the same cascade levels were closely comparable, and the aerosol particles were able to reach the small aerosol-sized cascades at the lower levels to some extent.

Identifying macrofloating debris hotspots in the Mediterranean Sea applying multiplatform methodologies

The Mediterranean Sea is considered the world's sixth greatest hotspot for marine litter; however, quantifying the extent of marine debris in the oceans is a challenge, especially due to variations in survey methodologies. This study aims to assess the spatial abundance and distribution of macrofloating debris (> 2.5 cm) in the Mediterranean basin through visual surveys carried out by methods (research vessel, sailing vessel, and aerial) and approaches (science and citizen science). Aerial and research vessel surveys estimated litter at 1.88 ± 2.3 items·km−2 and 0.89 ± 1.61 items·km−2 respectively for the whole Mediterranean; moreover both methods agreed that the main macrofloating debris hotspots were in the east of Algeria, Tyrrhenian, Adriatic and Alboran Seas. Likewise, for the common blocks analysed aerial surveys estimated greater amounts of macrofloating debris than research vessels (mean 1.92 ± 2.61 items·km−2 vs. 0.94 ± 1.69 items·km−2) highlighting the different detection capacities of the two methods. In the Spanish Mediterranean continental shelf, results obtained from research vessels showed mean values of 8.6 ± 7.8 items·km−2 for 2021 and 3.86 ± 3.96 items·km−2 for 2022. Sailing vessels along the Spanish coastline registered up to 70.87 ± 257.23 items·km−2 in waters of the Cabrera Island, which is a Marine Protected Area. No significant differences between citizen science and scientific methods were found, which suggests that the implementation of this tool could be very useful in obtaining greater datasets. Results on the abundance of macrofloating debris could be attributed to various factors, including the influence of mighty rivers, a dense population in these areas, especially during some seasons like summer, and the effect of some currents and eddies, such as the Algerian and the northern currents, which also influence the transboundary plastics.

Investigating the deposition of fibrous zeolite particles on leaf surfaces: A novel low-cost method for detecting the presence of airborne hazardous mineral fibers

Naturally occurring fibrous minerals, such as erionite, can pose a significant threat to human health when disturbed and subsequently respired. Understanding the spatial abundance and characteristics of these hazardous fibrous minerals in ambient air is crucial for minimizing human exposure and assessing risk. Conventional detection methods for airborne hazardous mineral fibers, such as those developed for asbestos, are of limited utility in environmental settings where fiber concentrations are low and different fiber types may be present and can be costly especially when monitoring large areas over long periods of time. This study presents an innovative methodology for detecting and identifying the presence of airborne naturally occurring fibrous zeolites, using leaf surface deposition sampling, SEM-EDX analysis for the detection and assessment of elemental composition, and TEM-SAED with continuous rotation diffraction (MicroED) to determine their crystallographic unit cell parameters. In total, 309 fibrous zeolite particles (FZPs) were identified on a range of tree leaf surfaces across 80% of the sampling sites located close to both active and disused zeolite quarries in the Taupo Volcanic Region, New Zealand. The FZPs displayed various morphologies including aggregates, bundles, and fibril-like structures. Of the FZPs detected, 91.2% were < 5µm in length. Tetrahedral Si:(Si+Al) ratio results indicated that 40% of the FZPs were in the reference range for zeolite mordenite. TEM-SAED plus MicroED analysis resulted in 61% of tested FZPs indexed to unit cell parameters that matched with mordenite. This research demonstrates the potential of leaf sampling as a cost-effective method for detecting airborne FZPs while the MicroED data can be utilized for distinguishing between different types of airborne fibrous zeolites in ambient air.

Chemical Abundance Gradients of Organic Molecules within a Protostellar Disk

Observations of low-mass protostellar systems show evidence of rich, complex organic chemistry. Their low luminosity, however, makes determining abundance distributions of complex organic molecules within the water snowline challenging. However, the excitation conditions sampled by differing molecular distributions may produce substantive changes in the resulting emission. Thus, molecular excitation may recover spatial information from spatially unresolved data. By analyzing spatially unresolved NOrthern Extended Millimeter Array observations of CH3OH and CH3CN, we aim to determine if CH3OH and CH3CN are distributed differently in the protostellar disk around HOPS-370, a highly luminous intermediate-mass protostar. Rotational diagram analysis of CH3OH and CH3CN yields rotational temperatures of 198 ± 1.2 K and 448 ± 19 K, respectively, suggesting the two molecules have different spatial distributions. Source-specific 3D LTE radiative transfer models are used to constrain the spatial distribution of CH3OH and CH3CN within the disk. A uniform distribution with an abundance of 4 × 10−8 reproduces the CH3OH observations. In contrast, the spatial distribution of CH3CN needs to be either more compact (within ∼120 au versus ∼240 au for CH3OH) or exhibit a factor of ≳15 increase in abundance in the inner ∼55 au. A possible explanation for the difference in spatial abundance distributions of CH3OH and CH3CN is carbon-grain sublimation.

Understanding mammal resource choices and subsistence strategies during the Holocene Climate Optimum: Integration of evidence from palaeodistribution modelling, animal bones and archaeological remains in the farming-pastoral ecotone, northern China

The farming-pastoral ecotone (FPE) is considered to be the most sensitive and unstable area in relation to the surrounding environment in northern China. The ecological improvement during the Holocene Climate Optimum (HCO) profoundly influenced livelihoods and adaptability of early sedentary communities. The reason for diverse utilization of mammals and specific subsistence strategies among different FPE sites remains unclear due to the lack of reconstructions demonstrating explicit spatial distribution and abundance of species that people ate. In five case studies during HCO from FPE in China, I illustrate what palaeodistribution modelling powered by Species Distribution Models (SDMs) tells us about three different large and medium-sized mammal species, and how the integration of this information with Site Catchment Analysis (SCA) helps to understand resource choices and subsistence strategies in these different sites. Analysis indicates that reduced residential mobility at FPE during HCO is associated with the spatial distribution of mammals within site catchments. Inhabitants of the ecotone may adapt to distinct mammal resources by long-distance logistical mobility, high residential mobility, improving technological flexibility, or intensifying the utilization of certain wild species. This evidence provides valuable insights into the highly flexible adaptability of early sedentism in FPE.

Spatial heterogeneity and prognostic significance of TAMs and TILs infiltrates in different staging esophageal squamous carcinoma

BackgroundThe prognostic value and clinical relevance of tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) in esophageal squamous cell carcinoma (ESCC) remain unclear. AimsTo investigate the prognostic value and functional involvement of TILs in ESCC. MethodsWe included 40 patients across different stages of ESCC from Xinjiang. Multiplex fluorescent immunohistochemistry characterized TILs and TAMs. TILs in different tumor regions were quantified and correlated with overall survival (OS) using log-rank test and Cox regression analyses. ResultsInvasive ESCC exhibited increased CD4 T cells and Tregs compared to carcinoma in situ, with a higher Tregs/CD4 T cells ratio (p < 0.05). TAMs, primarily in stromal regions, were significantly associated with Foxp3+ cells (p < 0.05). Higher infiltration of stromal TAMs and a higher CD4/CD8 T cells ratio correlated with poorer OS, while a higher CD8 T/Foxp3+ cells ratio indicated better survival. Multivariate Cox analysis revealed TNM stage, tumor length, and stromal CD4/CD8 T cells ratio as independent prognostic factors (p < 0.05). An immune prognostic risk score-based nomogram was constructed to predict patient outcomes. ConclusionsThe spatial distribution and abundance of TILs significantly correlated with prognosis, providing a useful immune classification for ESCC.

Modelling bluetongue and African horse sickness vector (Culicoides spp.) distribution in the Western Cape in South Africa using random forest machine learning.

Culicoides biting midges exhibit a global spatial distribution and are the main vectors of several viruses of veterinary importance, including bluetongue (BT) and African horse sickness (AHS). Many environmental and anthropological factors contribute to their ability to live in a variety of habitats, which have the potential to change over the years as the climate changes. Therefore, as new habitats emerge, the risk for new introductions of these diseases of interest to occur increases. The aim of this study was to model distributions for two primary vectors for BT and AHS (Culicoides imicola and Culicoides bolitinos) using random forest (RF) machine learning and explore the relative importance of environmental and anthropological factors in a region of South Africa with frequent AHS and BT outbreaks. Culicoides capture data were collected between 1996 and 2022 across 171 different capture locations in the Western Cape. Predictor variables included climate-related variables (temperature, precipitation, humidity), environment-related variables (normalised difference vegetation index-NDVI, soil moisture) and farm-related variables (livestock densities). Random forest (RF) models were developed to explore the spatial distributions of C. imicola, C. bolitinos and a merged species map, where both competent vectors were combined. The maps were then compared to interpolation maps using the same capture data as well as historical locations of BT and AHS outbreaks. Overall, the RF models performed well with 75.02%, 61.6% and 74.01% variance explained for C. imicola, C. bolitinos and merged species models respectively. Cattle density was the most important predictor for C. imicola and water vapour pressure the most important for C. bolitinos. Compared to interpolation maps, the RF models had higher predictive power throughout most of the year when species were modelled individually; however, when merged, the interpolation maps performed better in all seasons except winter. Finally, midge densities did not show any conclusive correlation with BT or AHS outbreaks. This study yielded novel insight into the spatial abundance and drivers of abundance of competent vectors of BT and AHS. It also provided valuable data to inform mathematical models exploring disease outbreaks so that Culicoides-transmitted diseases in South Africa can be further analysed.

Abundance, distribution, and dynamics of Anopheles species (Diptera: Culicidae) in Iowa, United States.

Malaria was once endemic in the United States prior to its elimination in 1951. However, due to consistent introductions of travel-associated malaria cases and the presence of several native Anopheles species (Diptera: Culicidae) that are competent vectors of malaria, the potential for local (autochthonous) malaria transmission remains a persistent threat in the United States. While several intermittent cases of local malaria transmission have occurred in the United States in the decades since elimination, the emergence of autochthonous transmission in 4 states in 2023 demonstrates the continued risk for future outbreaks. Moreover, these recent examples also highlight significant gaps in current mosquito surveillance efforts that have predominantly focused on threats of arboviral disease, such that our understanding of Anopheles distributions relies only on historical records and offers limited insight into the ecological factors that influence their abundance. Herein, we summarize mosquito surveillance data collected over the last 20 years (2004-2023) across 59 Iowa counties to provide essential information into the spatial distribution, temporal abundance, and trap preferences of Anopheles species in the state. Further analyses of the 2 most abundant species, Anopheles punctipennis Say and Anopheles quadrimaculatus Say, reveal the additional influence of precipitation and forested habitats in defining An. punctipennis abundance. Together, we believe these results provide an increased understanding of previously neglected Anopheles species that have the potential for autochthonous malaria transmission in Iowa and that can be extended to other regions of the United States to enhance preparedness for future malaria outbreaks.

Introducing IsoMad, a compilation of isotopic datasets for Madagascar

We present the first open-access, island-wide isotopic database (IsoMad) for modern biologically relevant materials collected on Madagascar within the past 150 years from both terrestrial and nearshore marine environments. Isotopic research on the island has increasingly helped with biological studies of endemic organisms, including evaluating foraging niches and investigating factors that affect the spatial distribution and abundance of species. The IsoMad database should facilitate future work by making it easy for researchers to access existing data (even for those who are relatively unfamiliar with the literature) and identify both research gaps and opportunities for using various isotope systems to answer research questions. We also hope that this database will encourage full data reporting in future publications.

The effect of the tidal cycle on the phytoplankton community assemblage in a mangrove-dominated tropical tidal creek.

A comparative assessment of phytoplankton dynamics during low tide (LT) and high tide (HT) was conducted from February 2022 to January 2023 in a tropical mesotidal creek, Manori, Mumbai, India. In total, 124 phytoplankton species were recorded. The HT resulted in greater species richness (124 species) and diversity indices (Shannon-Wiener's index) than the LT (102 species). The Pielou's evenness (J') and Simpson's dominance index (1-D) did not show significant fluctuations with the tides due to the marine phytoplankton species moving rhythmically in and out of the creek with the tides. Overall, the seasonal abundance was maximum during pre-monsoon at HT (5.79 × 103 u/L) and lowest in monsoon at LT (0.45 × 103 u/L), whereas spatial abundance was maximum at S1 (HT- 4.04 × 103 u/L) at HT and lowest at S3 (LT- 0.75 × 103 u/L) at LT. The diatoms dominated in their abundance (1.83 × 103 u/L and 3.82 × 103 u/L in HT) and diversity (77 in LT and 92 in HT). The species such as Coscinodiscus centralis, Coscinodiscus granii, Coscinodiscus radiatus, Triops furca, Melosira varians, Nitzchsia palea, Chaetoceros affinis, Skeletonema marinoi, Stephanocyclus meneghinianus, Planktoniella sol and Skeletonema costatumwere the dominant native residents in the creek. SIMPER analysis revealed that the maximum similarity was during the monsoon (47.65%), and the minimum was during the pre-monsoon (38.10%) at LT. However, in HT, the maximum similarity of phytoplankton shifted to post-monsoon (63.85%) and the minimum during the pre-monsoon (46.71%). The mean value of richness (d') and Shannon's diversity (H') showed a moderate phytoplankton diversity in the system. The environmental parameters (water temperature > pH > nitrate > salinity > DO > Alk > silicate) have a greater influence on the distribution of the phytoplankton community with tides as revealed by the Canonical correspondence analysis. Therefore, it has been found that tides play a significant role in the distribution and abundance of the phytoplankton community in a mesotidal creek environment.

Uncovering habitat associations and thresholds—insights for managing breeding waterfowl in Eastern Canada

ContextUnderstanding how habitat influences species abundance is crucial in developing ecologically sound wildlife conservation management plans. Exploring habitat associations and ecological thresholds in species’ responses allows for better conservation and management on a landscape-scale.ObjectivesThis work aimed to identify habitat drivers and response thresholds of waterfowl and waterbird species’ densities in eastern Canada to support key landscape-level decisions for habitat conservation and wetland management.MethodsWe developed predictive abundance models for 17 species across eastern Canada from 2001 to 2015 using data from four regional surveys and identified areas where prioritizing enhancement of wetlands would increase the breeding density of five priority waterfowl species.ResultsHabitat associations and spatial abundance patterns varied across species, but most species responded strongly to forest composition, agriculture, and wetland features. Threshold effects occurred and varied among species, yet generally once 14% of a plot was covered in wetlands, positive effects of increased wetland diminished for most species. Our results allow for the targeting of investments in increasing wetland area along portions of eastern Canada that provide the best opportunities to increase breeding densities for priority waterfowl species.ConclusionsUnderstanding species-habitat associations and response thresholds allows for landscape management and planning and prioritization of limited resources. We suggest that management and wetland enhancement efforts for waterfowl in eastern Canada should be guided by predictive models and response thresholds of key habitat attributes to best prioritize actions that will have the biggest positive impact on multiple species.

Seasonal and Spatial Distribution of Zooplankton Communities with Relation to some Physico-Chemical Parameters in the South East Coast of Bangladesh

Seasonal and spatial distribution of zooplankton communities in relation with some physico-chemical parameters in the south eastern coastal waters of Bangladesh was carried out from January 2016 to November 2016. Zooplankton samples were collected from seven different selected stations covering various ecosystems, viz.: Riverine (Bhola, Barishal &amp; Chandpur), Offshore Island water (Sandwip &amp; Hatia) and Nearshore (Cox’s bazar &amp; Naf River) regions. In total 33 genera were recorded during sampling periods and the highest abundance of zooplankton were recorded at Naf River (331.318 ind/m3) and the lowest at Chandpur (22.6414ind/m3) during post-monsoon. In pre-monsoon the highest abundance was recorded at Sandwip (31.49435ind/m3) and the lowest at Bhola (8.239854ind/m3). During monsoon the highest abundance was recorded at Cox’s Bazar (51.64085ind/m3) and the lowest at Barishal (4.389972ind/m3). A total of 24, 22 and 32 individuals (genera) of zooplankton identified during monsoon, pre-monsoon and post-monsoon respectively from all sampling stations. Calanoida, Cyclopoida, Fish larvae, Lucifer and Shrimp Zoea were common in every sampling station. Dictoyptera was the only species found in marine water. The statistical analysis of water quality parameters as temperature, pH, salinity, transparency, DO, TDS and TSS indicated the substantial relationship with seasonal and spatial distribution, diversity and abundance of zooplankton. Diversity index also indicated seasonal and spatial variation of zooplankton communities in the south eastern coastal waters of Bangladesh. The Chittagong Univ. J. B. Sci.,Vol. 10(1 &amp;2):95-119, 2020

In situ imaging of LPMO action on plant tissues

Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that oxidatively cleave recalcitrant polysaccharides such as cellulose. Several studies have reported LPMO action in synergy with other carbohydrate-active enzymes (CAZymes) for the degradation of lignocellulosic biomass but direct LPMO action at the plant tissue level remains challenging to investigate. Here, we have developed a MALDI-MS imaging workflow to detect oxidised oligosaccharides released by a cellulose-active LPMO at cellular level on maize tissues. Using this workflow, we imaged LPMO action and gained insight into the spatial variation and relative abundance of oxidised and non-oxidised oligosaccharides. We reveal a targeted action of the LPMO related to the composition and organisation of plant cell walls.

Environmental risk assessment, spatial distribution, and abundance of heavy metals in surface sediments of Dal Lake-Kashmir, India

This study assesses the pollution levels of Dal Lake in Kashmir, India, focusing on the spatial distribution, abundance, and risk of heavy metals in surface sediments. Granulometric analysis revealed a complex interplay of sedimentation processes, characterized by a wide range of sand (1.25% to 47.03%), silt (2.65% to 58.21%), and clay (38.35% to 94.48%) contents across sediment samples. The average CaCO3 content of 18.65% is notably higher than observed in other regional and global lakes, indicating higher production or preservation of carbonates. The organic matter (OM) content within the sediment samples varied significantly, ranging from 3.9% to 25.01%, reflecting complex sedimentary dynamics. Utilizing environmental assessment indices (Contamination Factor, degree of contamination, Pollution Load Index, Potential ecological risk index, Enrichment Factor, and Geo-accumulation Index) and multivariate statistical analyses (Pearson's Correlation, Principal Component Analysis, Cluster Analysis), it examines the contamination by Iron, Manganese, Cobalt, Chromium, Copper, Nickel, Lead, and Zinc across 32 samples. Results indicate spatial variability in metal concentrations, with Cobalt ranging from 24.1178 ppm to 52.95 ppm and Iron from 25,800.99 ppm to 164,747.82 ppm, highlighting areas of significant contamination and potential ecological risks, especially from Nickel, which exceeds safe levels for benthic invertebrates. The Pollution Load Index suggests moderate contamination of the lake. These findings emphasize the urgent need for continuous monitoring and effective management to protect Dal Lake's ecological integrity.

Spatial Distribution and Abundance of a Pelagic Squid during the Evolution of Eddies in the Southeast Pacific Ocean

The Humboldt squid (Dosidicus gigas), is a significant economic species off Peru. The abundance and distribution of the species are highly susceptible to fluctuations in marine environmental conditions. The evolution of mesoscale eddies represents one of the dynamic processes in the ocean, exerting varying degrees of influence on regional biogeochemical processes from generation to dissipation. However, the mechanisms governing the regulation of abundance and spatial distribution of D. gigas off Peru during this evolution remain unclear. Therefore, this study employed normalization techniques and the habitat suitability index (HSI) model, utilizing data from the D. gigas fishery, mesoscale eddies, and marine environmental factors (including sea surface temperature, temperature at 50 m depth, and chlorophyll-a concentration) to analyze the environmental changes and the abundance, spatial distribution, and habitat changes of D. gigas during the evolution of mesoscale eddies. The results indicate that eddies undergo four stages: formation, intensification, maturity, and decay. During eddy evolution, the abundance of D. gigas exhibited an initial increase and a subsequent decrease within cyclonic eddies (CEs), whereas, within anticyclonic eddies (AEs), abundance showed a gradual decline. The outcome of the HSI model revealed that, the habitat suitability and the proportion of suitable habitat areas within eddies were highly consistent with the abundance of D. gigas during all stages of the eddies other than the intensification stage of AEs. The study speculated that both CEs and AEs can create favorable environmental conditions during the maturity stage, thereby leading to an increase in suitable habitat and abundance of D. gigas. These findings emphasize the significant impact of mesoscale eddy evolution on the abundance and habitat distribution of D. gigas.

Characterization of deep-sea sponge ground (Asconema setubalense) using structure from motion methodology.

The hexactinellid sponge Asconema setubalenseKent, 1870 is a deep-sea species characterized by its expansive cup-shaped morphology, which contributes significantly to the three-dimensional complexity of the marine ecosystems. This sponge forms grounds that offer protection to pelagic organisms and juvenile stages. Despite its ecological relevance, there is a lack of information on the ecology, behavior and population structure of this species. The research aimed to conduct a multitemporal analysis of this sponge in the Aviles Canyon System over a ten-year period, focusing on spatial distribution and abundance. Changes in fishing pressure were estimated using the presence of fishing gears as a proxy. Additionally, the study sought to provide a detailed morphometric description through 3D photogrammetric reconstructions based on the latest data. The multi-temporal analysis revealed a subtle increase in sponge density, particularly at depths ranging from 320 to 390 m, exhibiting an irregular spatial distribution in 2022, with maximal values of 0.08 individuals/m2. Despite a small decrease on the loss of fishing gears in the overlapping area between samplings in 2012 and 2022, there was not a clear indication of a decline in fishing pressure over the years. Notably, more sightings of fishing gears were found in transect IC222TV_16 (0.07 gears/m2) than in IC222_TV02 (0.04 gears/m2) in 2022, suggesting potential spatial preferences for fishing activities. Visual analysis of temporal populations revealed an increase of 7% in specimen perturbations over ten years, with the population in IC222_TV16 being healthier (9% of the individuals presenting severe deformations) than in IC222_TV02 (40%). High-density fishing gear locations coincided with areas inhabited by sponges displaying the highest perturbation levels in both transects. Morphometric analysis using data from 2022 indicated a prevalence of individuals with heights concentrated between 0.18 and 0.38 m, osculum and flounce diameters reaching 0.4 and 0.56 m and osculum and flounce surfaces of 0.02–0.04 and 0.06–0.19 m2 respectively. Over 80% of measured specimens exhibited a high degree of asymmetry. Strong correlations were observed between heights and osculum and flounce surfaces, but external factors may be included for explaining wall deformities. These findings contribute valuable insights into the characterization of A. setubalense, serving as a foundation for future research in the area. Moreover, this work highlights the promising potential of photogrammetry as an efficient tool for monitoring of vulnerable marine ecosystems (VME) and marine protected areas.

Spatial metabolomics reveal metabolic alternations in the injured mice kidneys induced by triclocarban treatment

Triclocarban (TCC) is a common antimicrobial agent that has been widely used in medical care. Given the close association between TCC treatment and metabolic disorders, we assessed whether long-term treatment to TCC at a human-relevant concentration could induce nephrotoxicity by disrupting the metabolic levels in a mouse model. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was applied to investigate the alterations in the spatial distributions and abundances of TCC, endogenous and exogenous metabolites in the kidney after TCC treatment. The results showed that TCC treatment induced the changes in the organ weight, organ coefficient and histopathology of the mouse kidney. MSI data reveled that TCC accumulated in the all regions of the kidney, while its five metabolites mainly distributed in the cortex regions. The abundances of 79 biomolecules associated with pathways of leukotriene E4 metabolism, biosythesis and degradation of glycerophospholipids and glycerolipids, ceramide-to-sphingomyelin signaling were significantly altered in the kidney after TCC treatment. These biomolecules showed distinctive distributions in the kidney and displayed a favorable spatial correlation with the pathological damage. This work offers new insights into the related mechanisms of TCC-induced nephrotocicity and exhibits the potential of MALDI-MSI-based spatial metabolomics as a promising approach for the risk assessment of agents in medical care.

Clustered and rotating designs as a strategy to obtain precise detection rates in camera trapping studies

Abstract Camera traps have transformed the way we monitor wildlife and are now routinely used to address questions from a wide range of ecological and conservation aspects. Sampling design optimization and a better understanding of drivers determining the precision of detection rates (i.e. the number of detections per unit of effort) are important methodological issues. Little attention has been focused on the effect of placing more than one camera on each sampling point (hereafter, clustered design), and/or rotating (i.e. redeploying) the cameras to new placements during the sampling period. We explored the differences in the precision of detection rates between clustered vs. single camera designs when cameras remained in the same location during the study. Furthermore, the effect of keeping the placement of cameras fixed or rotating them (i.e. moving them to new locations during the sampling period), when a limited number of camera devices are available, was also evaluated. We used simulations and field data to test differences in detection rate precision for the different sampling designs. We simulated three different population distributions (random, trail‐based and aggregated) and three abundance scenarios. The simulations were validated with a field experiment focused on eight species with different behavioural traits, including artiodactyls, carnivores, lagomorphs, and birds. When a fixed number of sampling points were monitored simultaneously, clustered designs generally resulted in an increase in the precision of detection rates compared to single designs. The absolute reduction in the coefficient of variation by clustered designs was on average 0.07 units (min: 0.01, max: 0.15), which represents an average relative reduction in CV of 31% (min:6%, max:44%). An improvement in precision was also observed as a higher number of sampling points was used for all population distributions and sampling designs tested. When a fixed number of cameras were available, rotating the cameras to independent locations improved precision (an absolute reduction of 0.19 CV units) when monitoring aggregated populations, but not for random and trail‐based population distributions. Synthesis and applications: Our research provides a guideline for wildlife managers and researchers to improve the precision of camera trap detection rates and optimize resource allocation. In general, the study design should accommodate the behaviour of the target species (e.g. spatial aggregation and abundance), monitoring program logistic resources (both human and economic) and study area characteristics (e.g. accessibility and vandalism).