Peru Basin Research Articles

Accurate Identification Method of Small-Size Polymetallic Nodules Based on Seafloor Hyperspectral Data

Polymetallic nodules are spherical or ellipsoidal mineral aggregates formed naturally in deep-sea environments. They contain a variety of metallic elements and are important solid mineral resources on the seabed. How best to quickly and accurately identify polymetallic nodules is one of the key questions of marine development and deep-sea-mineral-resource utilization. We propose a method that uses YOLOv5s as a reference network and integrates the IoU (Intersection over Union) and the Wasserstein distance in the optimal transmission theory to accurately identify different sizes of polymetallic nodules. Experiment using deep-sea hyperspectral data obtained from the Peru Basin was performed. The results showed that better recognition effects were achieved when the fusion ratio of overlap and Wasserstein distance metric was 0.5, and the accuracy of the proposed algorithm reached 84.5%, which was 6.2% higher than that of the original baseline network. In addition, the rest of the performance indexes were also improved significantly compared to traditional methods.

Effect of Broadness of Wave Spectrum on Significant Wave Height and Wave Power for Open Ocean Conditions of the Peru Basin

Abstract When estimating significant wave height and wave power, it is regularly assumed 4 for the spectral estimate factor. It means considering a narrowband wave spectrum. That approach is accurate enough when the spectral broadness parameter is near zero. Since the Peru Basin is an open ocean: swells and local wind waves can overlap; therefore, its wave spectrum should be considered broadband. This work aims to demonstrate that the wave spectrum in the Peru Basin has waves in a broad band of frequencies and also discuss how this characteristic affects estimating the significant wave height and wave power. The methodology comprises numerical methods, inferential statistics, and spectral analysis applied to ocean data. The paper's conclusions declare the Peru Basin wave spectrum as broadband. The estimated significant wave height for broadband wave spectrum is 7% lower than if the wave spectrum was considered narrowband. We propose 3.7 as the spectral estimate factor for calculating the significant wave height in the Peru Basin instead of the commonly used 4. The significant wave height error when assuming a narrowband wave spectrum slightly affects the spectral parametric wave power calculation, causing a maximum overestimation of 5%. Nevertheless, accurately estimating significant wave height is critical for diverse marine technologies.

Short and decadal impacts of seafloor physical perturbation on the abundances of Lebensspuren ‘traces of life’ in the Peru Basin manganese nodule province

Interest in deep-sea mining for polymetallic nodules as an alternative source to onshore mines for various high-technology metals has risen in recent years, as demands and costs have increased. The need for studies to assess its short- and long-term consequences on polymetallic nodule ecosystems is therefore also increasingly prescient. Recent image-based expedition studies have described the temporal impacts on epi-/megafauna seafloor communities across these ecosystems at particular points in time. However, these studies have failed to capture information on large infauna within the sediments or give information on potential transient and temporally limited users of these areas, such as mobile surface deposit feeders or fauna responding to bloom events or food fall depositions. This study uses data from the Peru Basin polymetallic nodule province, where the seafloor was previously disturbed with a plough harrow in 1989 and with an epibenthic sled (EBS) in 2015, to simulate two contrasting possible impact forms of mining disturbance. To try and address the shortfall on information on transient epifauna and infauna use of these various disturbed and undisturbed areas of nodule-rich seafloor, images collected 6 months after the 2015 disturbance event were inspected and all Lebensspuren, ‘traces of life’, were characterized by type (epi- or infauna tracemakers, as well as forming fauna species where possible), along with whether they occurred on undisturbed seafloor or regions disturbed in 1989 or 2015. The results show that epi- and endobenthic Lebensspuren were at least 50% less abundant across both the ploughed and EBS disturbed seafloors. This indicates that even 26 years after disturbance, sediment use by fauna may remain depressed across these areas.

Chronology and Paleoenvironment of the Tunga Formation, a new lowermost Miocene sequence in the East Pisco Basin of southern Peru

The East Pisco Basin, occupying the coastal plain of Peru between 13°S and 16°S, is widely known for its extensive Eocene to Quaternary biosiliceous deposits and excellent preservation of fossil marine vertebrates. Biochronologic studies published over the past 35 years record a hiatus of about 13 million years (*32–19 Ma) separating the youngest Paleogene deposits (Otuma Formation) from the oldest Neogene deposits (Chilcatay Formation). We describe a newly identified Lower Miocene depositional sequence that lies below documented Chilcatay strata, rich in diatoms and benthic foraminifers, which we name the Tunga Formation. A low-latitude diatom assemblage from the Tunga Formation indicates an age of 21.6 to 20.5 Ma age, whereas an ash within basal Tunga strata yields an 206Pb/238U weighted mean age of 20.58 ± 0.13 Ma. Benthic foraminifer paleodepth analysis and the diatom assemblage of the Tunga Formation indicate deposition took place along the continental margin at upper bathyal depths under hypoxic conditions beneath highly productive waters, a scenario also supported by the presence of abundant clupeoid fish scales and dolomitized horizons. The Tunga Formation is characterized by a profound scarcity of cetacean fossils, unlike the cetacean-rich neritic sediments of the overlying Chilcatay Formation.

Architecture and Authority: A Spatial Analysis of Power and Control at Three Spanish Colonial Silver Refineries (Puno, Peru)

This paper examines the spatial layout of three Spanish colonial silver refineries from the western Lake Titicaca Basin of southern Peru. These sites, located approximately 15 km from the city of Puno, Peru, were operated by Indigenous laborers throughout the Middle Colonial period (AD 1600–1800). Space syntax analysis is employed to evaluate the degree of control and access across these sites, examining the location of dormitories, storage buildings, administrative patios, work areas, entrances, and exits. Using both intra- and inter-site comparisons, results indicate the presence of restricted and segregated areas at all three refineries. However, inter-site comparisons highlight the integrated nature of the smaller, more rural refineries, revealing how control of labor manifested in diverse ways at the local scale.

A new species of Lelegeis Champion, 1886 from lowland natural forest of the Amazon basin of Peru (Coleoptera: Tenebrionidae, Diaperini).

A new species of Lelegeis Champion, 1886 from lowland natural forest of the Amazon basin of Peru (Coleoptera: Tenebrionidae, Diaperini).

Major fine-scale spatial heterogeneity in accumulation of gelatinous carbon fluxes on the deep seabed

Abyssal plain communities rely on the overlying water column for a settling flux of organic matter. The origin and rate of this flux as well as the controls on its fine-scale spatial distribution following seafloor settlement are largely unquantified. This is particularly true across regions where anthropogenically-induced seafloor disturbance has occurred. Here, we observed, quantified and mapped a mass deposition event of gelatinous zooplankton carcasses (pyrosomes) in July-September 2015 across one such physically disturbed region in the Peru Basin polymetallic nodule province (4150 m). Seafloor in this area was disturbed with a plough harrow in 1989 (as part of the DISCOL experiment) causing troughs in the sediment. Other parts were disturbed with an epibenthic sled (EBS) during a cruise in 2015 resulting in steep-walled, U-shaped troughs. We investigated two hypotheses: a) gelatinous food falls contribute significantly to the abyssal plain carbon pump and b) physical seafloor disturbance influences abyssal distribution of organic matter. We combined optical and bathymetric seafloor observations, to analyze pyrosome distribution on seabeds with different levels of disturbance. 2954 pyrosome colonies and associated taxa were detected in > 14,000 seafloor images. The mean regional carbon (C) deposition associated with pyrosome carcasses was significant compared to the flux of particulate organic C (182 to 1543%), and the total respired benthic C flux in the DISCOL Experimental Area (39 to 184%). EBS-disturbed seafloor tracks contained 72 times more pyrosome-associated C than an undisturbed reference site, and up to 4 times more than an area disturbed in 1989. Deposited pyrosomes collected had a higher proportion of labile fatty acids compared to the sediment. We document the temporal and spatial extent of an abyssal food fall event with unprecedented detail and show that physical seafloor disturbance results in the accumulation of detrital material. Such accumulation may reduce oxygen availability and alter benthic community structure. Understanding both the relevance of large food falls and the fine scale topography of the seafloor, is necessary for impact assessment of technologies altering seafloor integrity (e.g. as a result of bottom-trawling or deep seabed mining) and may improve their management on a global scale.

Evaluation of Soil Loss and Sediment Yield Based on GIS and Remote Sensing Techniques in a Complex Amazon Mountain Basin of Peru: Case Study Mayo River Basin, San Martin Region

This study aims to estimate the average annual rate of soil loss by rainfall in terms of spatial distribution and sediment rate using RUSLE and GIS techniques. Additionally, remote sensing and available soil property information are applied for erosion analysis. The work reveals a very severe type of soil erosion, with the highest mean rate in the steep areas. Annual mean erosion in many parts of the basin is in the range of 0 to 9237.0 t/km2/year with an average of 403 t/km2/year. Approximately 45% (in the upper basin) of the total area has moderate to high soil loss by water, especially in five catchments, namely Serranoyacu, Naranjos, Naranjillo, Yuracyacu, and Tonchima at 886.8 t/km2/yr, 985.1 t/km2/yr, 691.3 t/km2/yr, 567.3 t/km2/yr, and 506.9 t/km2/yr, respectively. Catchment-wise soil loss estimates suggest that these areas are experiencing much higher soil loss in comparison to others; hence, these catchments are prioritized for soil conservation efforts. Sediment rate assessments indicate high sediment deposition along the flow direction of the mainstream of the catchment; in the upper Mayo part, the highest sediment rates are in Yuracyacu, Serranoyacu and Tonchima. Finally, the parts most vulnerable to increased erosion rate are the central part of the basin, which indicates progressive sediment deposition.

On the Estimation of the Wave Energy Period and a Kernel Proposal for the Peru Basin

The energy period is a crucial parameter needed for assessing wave energy. This parameter is regularly approximated using standard wave spectrums that do not always characterise an actual ocean region, even more if this region is far from the Northern Hemisphere, where most of the energy period approximations have been developed. In this work, diverse approximations for the energy period were evaluated using spectral data from a region of the Peru Basin. It included the assessment of a proposed Kernel “coefficient” curve. They were assessed regarding their time series, wave climate, and temporal variability. The time series analysis showed that the approximations based on the peak period do not have a realistic physical representation of ocean waves. On the other hand, the proposed Kernel correlation gave the best results for computing the energy period and the monthly/seasonal variability indexes for temporal variability analysis. Additionally, the correlations based on the zero-up-crossing period generated the best results for computing the coefficient of variation. Conversely, the highest errors were calculated for the correlations based on the traditional Bretschneider and JONSWAP spectrums. The wave climate indicated an annual average energy period equal to 9.8 s, considered stable due to its low variability.

Variations in Morphological and Geochemical Characteristics in Manganese Nodules from the East Siberian Arctic Shelf with Varying Water Depths

AbstractIn this study, we explore the morphological and geochemical characteristics for 440 manganese nodules collected from two different water depths [ARA12B-St52 (150 m, n = 239) and ARA12B-St58i (73 m, n = 201)] on the continental shelf of the East Siberian Sea from the ARA12B expedition in 2021. We also discussed the variations in the characteristics of manganese nodules with varying water depths in the Arctic Sea. The sizes of the nodules are generally greater than 3 cm at both sites. However, there is an obvious difference in the morphology with water depths. For the nodules collected at 150 m, brown-black colored tabular, tube, and ellipsoidal shapes with a rough surface texture are dominant. On the other hand, yellow-brown tabular shapes with a smooth surface texture are common for the nodules collected at 73 m. Furthermore, the slope of trend line between size and weight is significantly different at both sites: particularly, the slopes of nodules at 150 and 73 m are 1.60 and 0.84, respectively. This indicates the difference in the internal structure, porosity, and constituting elements between both nodules. Micro X-ray Flourescence (μ-XRF) results clearly demonstrate that the internal textures and chemical compositions are different with water depths. The nodules at 150 m are composed of a thick Mn-layer and a thin Fe-layer centered on the nucleus, while the nodules at 73 m are alternately grown with thin Mn- and Fe- layers around the nucleus. The average chemical compositions obtained by μ-XRF are 40.6 wt% Mn, 5.2 wt% Fe, and 7.9 Mn/Fe ratio at 150 m, and 10.3 wt% Mn, 19.0 wt% Fe, and 0.6 Mn/Fe ratio at 73 m. The chemical compositions of the nodules at 150 m are similar to those of nodules from the Peru Basin in the Pacific Ocean, while the compositions of the nodules at 73 m are similar to those of nodules from the Cook Islands or the Baltic Sea. The observed morphological and geochemical characteristics of the nodules show a clear difference at the two sites, which indicates that the aqueous conditions and formation processes of the nodules in the Arctic Sea vary with the water depths.이번 연구에서는 2021년 ARA12B 탐사를 통해 동시베리아해 대륙붕의 서로 다른 수심을 갖는 2개의 정점에서 수집한 망가니즈단괴 440개[ARA12B-St52 (150 m, n = 239), ARA12B-St58i (73 m, n = 201)]에 대하여 형태학적·지화학적 분석을 수행하고, 수심에 따른 단괴의 특성 변화를 고찰하였다. 단괴의 크기는 두 정점 모두에서 3 cm 이상의 크기가 일반적이다. 그러나 단괴의 외형적 특징은 수심에 따라 크게 차이가 있다. 수심 150 m에서 획득된 단괴의 일반적인 형태는 거친 표면조직을 가지는 갈색-흑색의 판상형, 원통형 및 타원체형이다. 반면, 수심 73 m에서 회수된 단괴들은 매끄러운 표면을 가지는 노랑-갈색의 판상형 단괴가 대부분을 차지한다. 또한 단괴의 내부조직, 공극률 및 구성원소와 관련이 있는 크기와 무게 간 추세선의 기울기는 150 m의 단괴의 경우 약 1.60, 83 m 단괴는 약 0.84로 큰 차이가 있음이 확인되었다. 이는 단괴의 내부조직 및 화학조성에 차이로부터 기인한다. 단괴의 내부조직과 화학조성 분석 결과, 수심 150 m의 단괴들은 핵을 중심으로 두꺼운 Mn층과 얇은 Fe층들로 이루어진 반면, 83 m의 단괴들은 핵을 중심으로 얇은 Mn 및 Fe층이 교호하며 성장한다. 마이크로 X선 형광분석(μ-XRF)을 통해 단괴의 절개면에서 분석된 평균 화학조성은 150 m 단괴의 경우 Mn 40.6 wt%, Fe 5.2 wt%, Mn/Fe 비 7.9이며, 83 m 단괴의 경우 Mn 10.3 wt%, Fe 19.0 wt%, Mn/Fe 비 0.6이다. 타 해역 단괴들의 화학조성과 비교한 결과 수심 150 m에서 회수된 단괴의 조성은 태평양의 페루 분지의 단괴들과 유사한 반면, 83 m에서 획득된 단괴의 조성은 태평양의 쿡 섬 또는 발트해의 단괴들과 유사하다. 관찰된 단괴들의 형태학적·지화학적 특성은 두 정점에서 뚜렷한 차이를 나타내며, 이는 북극해 대륙붕의 수심에 따라 단괴의 형성 당시의 환경적 조건에 명확한 차이가 있음을 지시한다.Keywords : East Siberian Sea, continental shelf, ARA12B expedition, manganese nodule, morphology

Delayed response of hermit crabs carrying anemones to a benthic impact experiment at the deep-sea nodule fields of the Peru Basin?

The deep Peru Basin is characterised by a unique abyssal scavenging community featuring large numbers of hermit crabs (Probeebei mirabilis, Decapoda, Crustacea). These are atypical hermit crabs, not carrying a shell, but on some occasions carrying an anemone (Actiniaria). The reason why some hermit crabs carry or not carry anemones is thought to be indicative of a changed environment, outweighing the cost/benefit of their relationship. Here we present the temporal variation of abundances of P. mirabilis with and without anemones, spanning more than two decades, following a benthic impact experiment. An overall decrease in hermit crab densities was observed, most noticeable and significant after 26 years and characterised by a loss of Actiniaria on the Probeebei mirabilis' pleon. Whether this is a delayed response to the benthic impact experiment carried out 26 years’ prior or a natural variation in the population remains to be corroborated by an extension of the time-series. Attention is drawn to the limitations of our knowledge over time and space of the abyssal community dynamics and the urgent necessity to fill in these gaps prior to any type of deep-sea exploitation.

Analysis of a new species of the Astyanax orthodus group (Characiformes: Characidae) from the upper Madre de Dios River, Amazon River Basin, Peru

Based on ten specimens, using morphometric, meristic and osteological characters, Astyanax leoni n. sp. is described from the upper Madre de Dios River drainage, Amazon River Basin of Peru. A. leoni n. sp. is a member of the Astyanax orthodus species group and is distinguished (except from A. multidens, A. villwocki, and A. gandhiae) in having an inconspicuous rod-shaped stripe on the caudal peduncle that extends anteriorly on top of a silver lateral stripe. It differs from the species mentioned above as follows: from A. multidens by having shorter chevron marks that cover up to only two series of scales above and below the apex of the chevron (vs. chevrons taller, with extensions that cover three series of scales); from A. villwocki by having chevron markings along the entire body (vs. no chevrons on the caudal peduncle); It differs from Astyanax gandhiae in having the caudal peduncle spot extending anteriorly to beyond the tip of the dorsal fin (vs. caudal peduncle spot not reaching anteriorly to tip of dorsal fin), and not of a uniform width as in A. villwocki. A dichotomous key to the species of Astyanax orthodus group is included.

Etiologies of Acute Undifferentiated Febrile Illnesses in and near Iquitos from 1993 to 1999 in the Amazon River Basin of Peru.

The objective of this study was to determine the etiology of febrile illnesses among patients from October 1, 1993 through September 30, 1999, in the urban community of Iquitos in the Amazon River Basin of Peru. Epidemiological and clinical data as well as blood samples were obtained from consenting patients at hospitals, health clinics and private residences. Samples were tested for arboviruses in cell cultures and for IgM and IgG antibodies by ELISA. Blood smears were examined for malaria, and sera were tested for antibodies to Leptospira spp. by ELISA and microscopic agglutination. Among 6,607 febrile patients studied, dengue viruses caused 14.6% of the cases, and Venezuelan equine encephalitis virus caused 2.5%, Oropouche virus 1.0%, Mayaro virus 0.4%, and other arboviruses caused 0.2% of the cases. Also, 22.9% of 4,844 patients tested were positive for malaria, and of 400 samples tested, 9% had evidence of acute leptospirosis. Although the study was not designed to assess the importance of these pathogens as a cause of human morbidity in the total population, these results indicate that arboviruses, leptospirosis, and malaria were the cause of approximately 50% of the febrile cases. Although the arboviruses that were diagnosed can produce asymptomatic infections, our findings increased the overall understanding of the relative health burden of these infections, as well as baseline knowledge needed for designing and implementing further studies to better assess the health impact and threat of these pathogens in the Amazon Basin of Peru.

Impact of returning scientific cruises and prolonged on-site presence on litter abundance at the deep-sea nodule fields in the Peru Basin.

Marine litter can be found along coasts, continental shelves and slopes, down into the abyss. The absence of light, low temperatures and low energy regimes characterising the deeper habitats ensure the persistence of litter over time. Therefore, manmade items within the deep sea will likely accumulate to increasing quantities. Here we report the litter abundance encountered at the Pacific abyssal nodule fields from the Peru Basin at 4150m depth. An average density of 2.67 litter items/ha was observed. Litter composed of plastic was the most abundant followed by metal and glass. At least 58% of the items observed could be linked to the research expeditions conducted in the area and appeared to be mostly accidental disposals from ships. The data gathered was used to address temporal trends in litter abundance as well as the impact of human on-site presence and return cruises in the context of future deep-sea mining efforts.

Taxonomic assessment of deep-sea decapod crustaceans collected from polymetallic nodule fields of the East Pacific Ocean using an integrative approach

Deep-sea decapod crustaceans (Crustacea: Decapoda) collected during nine research cruises to the Clarion-Clipperton Zone (CCZ) in the NE Pacific Ocean and the Peru Basin in the SE Pacific Ocean were studied comprehensively using an integrative taxonomic approach. The abyssal seafloors of both areas are rich in economically interesting polymetallic nodules. All specimens were morphologically identified and genetically analysed using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI). Eight species were collected, comprising three anomurans, three carideans, one dendrobranchiate, and one brachyuran, from water depths ranging between 4089 and 4511 m. COI sequences for representatives of the genera Parapagurus Smith, 1879, Ethusina SI Smith, 1884, and Bathystylodactylus Hanamura & Takeda, 1996 are provided for the first time. The molecular barcodes of the species provided herein will be valuable for the full taxonomic assignment of sequences produced in future metabarcoding and eDNA monitoring work. The new records extend the geographical distributional ranges or fill geographical gaps of the species reported, although none of the species is endemic to polymetallic nodule areas. This study is part of a taxonomic series aiming to describe the biodiversity of areas targeted for future deep-sea mining.

Dracophyes cepedai gen. et sp. nov., a new Dracoderidae genus and species (Kinorhyncha: Allomalorhagida) from the Peru Basin

A new Dracoderidae genus, Dracophyes gen. nov., and a new species Dracophyes cepedai sp. nov. from the Peru Basin are described. The new genus is characterized by the presence of acicular spines showing conspicuous intracuticular structures on segments 1–9 (either anchor for the dorsal or groove-like for the lateral series), alternating laterally displaced dorsal spines, becoming more lateral towards the posterior segments, males with two pairs of minute, poorly sclerotized penile spines, and its conspicuous obovate trunk shape. The new genus accommodates three species: Dracophyes toyoshioae comb. nov., Dracophyes chaac comb. nov. and D. cepedai sp. nov. The latter was collected in abyssal depths in the Peru Basin (East Pacific Ocean) and is recognised by having dorsal acicular spines on segments 1 to 9, alternating laterally displaced from the middorsal line, ventral acicular spines in ventrolateral position on segment 1, lateroventral position on segments 2–4 and 6–9, and in lateral accessory position on segment 5, tubes in lateroventral position on segment 5 and in lateral accessory position on segments 2 and 8, type 2 glandular cell outlets in lateroventral position on segment 10 and extremely long lateral terminal spines. Moreover, with the erection of the new genus, emended diagnoses for the family Dracoderidae and the former single genus within the family, Dracoderes, are proposed.

Diversity and distribution of Kinorhyncha in abyssal polymetallic nodule areas of the Clarion-Clipperton Fracture Zone and the Peru Basin, East Pacific Ocean, with the description of three new species and notes on their intraspecific variation

Polymetallic nodule fields represent a large reservoir of undiscovered biodiversity that becomes particularly evident for meiobenthic organisms, the smallest-sized faunal group. Knowledge gaps are especially noticeable for the generally low-density metazoan groups, such as Kinorhyncha, the so-called mud dragons. Using both morphological and genetic (metabarcoding) approaches, we provide a general overview and comparison of the diversity of kinorhynchs collected during nine sampling campaigns (2016–2019) that targeted abyssal environments in several contract areas for exploration in the Clarion-Clipperton Fracture Zone (CCZ) and in the Peru Basin. Our findings from morphological analyses reveal a highly diverse mud dragon community, with 16 species present in the CCZ. Of these, 12 appear in the German contract area, including three new species described in the present contribution: Echinoderes delaordeni sp. nov., Echinoderes sanctorum sp. nov., and Echinoderes zeppilliae sp. nov. Furthermore, metabarcoding data of the kinorhynch community gathered from the area is provided, together with the geographic distribution of the known species stated per contractor area, including new records and still undescribed species. Most of the identified species in the CCZ seem to have a wide distribution, with Echinoderes sp.4 being the most common and abundant species with a distribution spreading across the CCZ and also present in the Peru Basin. Metabarcoding analyses targeting the V1V2 hypervariable region of the 18S gene from the 253 stations of the CCZ revealed 14 amplicon sequence variants (ASVs) belonging to Kinorhyncha with grade values higher than 98% detected at 15 different stations within six different areas along the CCZ. Concurring with morphology, the family Echinoderidae was the most diverse as the genus Cephalorhyncha had five ASVs, followed by Echinoderes with four ASVs. Semnoderes, however, showed the widest spread ASV, being detected at six stations. In the CCZ, the metabarcoding data showed there were no shared ASVs between the CCZ areas as well as the highest number of uniques, which was 11. Our morphological study showed a low number of specimens inhabiting nodules (surface/crevices), suggesting that specific kinorhynch species do not typically inhabit the nodules in addition to the surrounding sediment.

Associated factors of the co-occurrence of trachoma and soil-transmitted helminthiases in children 1 to 9 years old in rural communities of the Amazon basin in Loreto Department, Peru: Results from a population-based survey.

BackgroundThere is evidence of the occurrence of trachoma in Peru, and studies have shown that soil-transmitted helminthiases (STH) are affecting rural communities in the Amazon basin in Loreto Department. This study was done to estimate trachoma prevalence, STH prevalence, and the associated factors for both diseases in children aged 1–9 years in rural communities of Peru.MethodologyA population-based cross-sectional survey was carried out in rural communities of Loreto. A standardized survey questionnaire with individual and household risk factors related to both diseases was used. Ocular examination was done for all participants aged one year and above, and eye swab samples were collected from children with follicular trachoma (TF). Anthropometric measurements, stool samples for STH, and blood samples for hemoglobin measurement were taken from children.Principal findingsTF prevalence was 7.74% (95% CI 5.08–11.63%), STH prevalence was 49.49% (95% CI 25.00–52.43%), and prevalence of co-occurrence of both diseases was 5.06% (95% CI 2.80–8.98%) in children aged 1–9 years. Being at age 3–8 years old (AOR = 6.76; 95% CI 1.346–33.947), have an unclean face (AOR = 24.64; 95% CI 6.787–89.444), and having been dewormed in the last six months (AOR = 2.47; 95% CI 1.106–5.514), were risk factors of TF. Being a female (AOR = 0.22; 95% CI 0.103–0.457) was associated with decreased odds of TF. Having been dewormed in the last six months (AOR = 0.30; 95% CI 0.139–0.628) was a preventative factor for STH. Risk factors for children with both diseases mirrored the findings for risk factors for individual diseases.ConclusionsNeglected tropical diseases and associated risk factors overlap in communities living in vulnerable conditions in the Amazon basin of Peru. These findings support the need to implement integrated interventions, including mass drug administration, water, sanitation, and hygiene for both diseases in the study area.

Fossil Bioapatites with Extremely High Concentrations of Rare Earth Elements and Yttrium from Deep-Sea Pelagic Sediments

Detailed geochemical and mineralogical insights into some of the richest rare earth elements and yttrium (REY)-containing bioapatites from ocean-floor sediments have been provided by combining laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), electron probe microanalysis (EPMA), Rietveld X-ray diffraction analysis, and Ce L3-edge high energy-resolution X-ray absorption near edge structure (HR-XANES) spectroscopy. Bioapatites at 1.94 and 4.70 m below the seafloor (mbsf) of the Clarion-Clipperton Zone (CCZ) of the Pacific Ocean have 26,600 (RSD = 15.7%, n = 20) and 30,300 (RSD = 14.6%, n = 10) mg/kg (mg/kg) total REY, respectively, and bioapatites at 2.28 and 6.95 mbsf of the Peru Basin have 15,500 (RSD = 15.6%, n = 20) and 15,700 (RSD = 17.8%, n = 29) mg/kg total REY, respectively. All bioapatite specimens have a variety of isomorphic substitutions in all atomic positions of the crystallographic structure. The average crystallochemical formula of bioapatites at 6.95 mbsf of the Peru Basin is [(PO4)2.71(SiO4)0.04(CO3,SO4)0.25][Ca4.57Na0.29Y0.04][F0.87Cl0.21]. All other substituents are below 0.04 atoms per formula unit. HR-XANES provides the first direct evidence for trivalent Ce in sediment apatites. The strong negative geochemical anomaly of Ce in fossil bioapatites is well explained by the occurrence of four valent Ce-MnO2 and CeO2 within the sediment and in seafloor ferromanganese nodules.

Seabed mining and blue growth: exploring the potential of marine mineral deposits as a sustainable source of rare earth elements (MaREEs) (IUPAC Technical Report)

Abstract The expected growth of the global economy and the projected rise in world population call for a greatly increased supply of materials critical for implementing clean technologies, such as rare earth elements (REEs) and other rare metals. Because the demand for critical metals is increasing and land-based mineral deposits are being depleted, seafloor resources are seen as the next frontier for mineral exploration and extraction. Marine mineral deposits with a great resource potential for transition, rare, and critical metals include mainly deep-sea mineral deposits, such as polymetallic sulfides, polymetallic nodules, cobalt-rich crusts, phosphorites, and rare earth element-rich muds. Major areas with economic interest for seabed mineral exploration and mining are the following: nodules in the Penrhyn Basin-Cook Islands Exclusive Economic Zone (EEZ), the Clarion–Clipperton nodule Zone, Peru Basin nodules, and the Central Indian Ocean Basin; seafloor massive sulfide deposits in the exclusive economic zones of Papua New Guinea, Japan, and New Zealand as well as the Mid-Atlantic Ridge and the three Indian Ocean spreading ridges; cobalt-rich crusts in the Pacific Prime Crust Zone and the Canary Islands Seamounts and the Rio Grande Rise in the Atlantic Ocean; and the rare earth element-rich deep-sea muds around Minamitorishima Island in the equatorial North Pacific. In addition, zones for marine phosphorites exploration are located in Chatham Rise, offshore Baja California, and on the shelf off Namibia. Moreover, shallow-water resources, like placer deposits, represent another marine source for many critical minerals, metals, and gems. The main concerns of deep-sea mining are related to its environmental impacts. Ecological impacts of rare earth element mining on deep-sea ecosystems are still poorly evaluated. Furthermore, marine mining may cause conflicts with various stakeholders such as fisheries, communications cable owners, offshore wind farms, and tourism. The global ocean is an immense source of food, energy, raw materials, clean water, and ecosystem services and suffers seriously by multiple stressors from anthropogenic sources. The development of a blue economy strategy needs a better knowledge of the environmental impacts. By protecting vulnerable areas, applying new technologies for deep-sea mineral exploration and mining, marine spatial planning, and a regulatory framework for minerals extraction, we may achieve sustainable management and use of our oceans.