Western Shore Research Articles

Seiche‐Induced Fish Kills in the Sea of Galilee—A Possible Explanation for Biblical Miracles?

AbstractIn Lake Kinneret (the biblical Sea of Galilee), Israel, internal waves of significant amplitude are induced by westerly winds. These waves give rise to upwelling into the surface mixed layer of colder, oxygen‐depleted water from the hypolimnetic and metalimnetic layers. If upwelling occurs soon after the onset of annual thermal stratification, when surface mixed layer extends over a narrow depth range, but the hypolimnion is already anoxic, there is a potential for massive fish kills as fish cannot escape the anoxic water that intrudes into the surface mixed layer along the western shore. This study uses a coupled three‐dimensional atmosphere‐lake model to elucidate the mechanisms behind these infrequent major fish kills in Lake Kinneret. Remarkably, nowadays fish‐kill events happen at the same location in the lake where the biblical Miracle of Loaves and Fishes and presumably the Miraculous Catch of Fish occurred two millennia before the present and may explain the appearance of large numbers of easy‐to‐collect fish close to the shore described in the biblical narratives.

A new species within the Enteromius kerstenii complex (Actinopterygii, Cyprinidae, Smiliogastrinae) from south-western Ethiopia

A new species of small-sized smiliogastrin barb, Enteromius gamo sp. nov., is described from tributaries to lakes Abaya and Chamo in south-western Ethiopia. The new species belongs to a readily diagnosable group commonly identified as E. kerstenii, exhibiting a thickened and serrated last unbranched ray in the dorsal fin, a low number of scales in the lateral series (≤ 27), and a yellow, orange or reddish blotch on operculum. Pairwise genetic distances between the new species from Ethiopia and specimens of E. kerstenii from close to the type locality in north-eastern Tanzania were 7.5–8.3 % (COI) and 8.9–10.1 % (cytb). Enteromius gamo sp. nov. is morphologically distinguished from E. kerstenii and all examined congeners from Tanzania, Kenya, and Uganda primarily by short anterior (15.8–35.1 %, mean 27.4 %, of snout length) and posterior (63.2–95.7 %, mean 81.0 %, of snout length) barbels. The new species is known only from wetlands and side channels of rivers (Hare, Sile, and Sago) along the western shores of lakes Abaya and Chamo.

Continuous Wavelet Transform Analysis of Climate Variability, Resiliency, and Restoration Strategies in Mesohaline Tidal Creeks

This research article employs the continuous wavelet transform analysis to identify the climatological effects among various water quality parameters to identify the successfulness of upland stream restoration on the receiving mesohaline tidal creeks. Estuaries and their corresponding tidal creeks have been impacted by human anthropogenic influences for decades, allowing a variety of restoration practices to be implemented in upland streams. In the face of climate variability and continuous human development pressures, this research performs statistical analysis and a wavelet coherence on, before, and after stream restoration for water quality changes in Chesapeake Bay’s tidal tributaries in the Lower Western Shore to identify if the restoration strategies have been effective in the mesohaline tidal creeks. Statistical analysis showed that currently, the receiving tidal basins are not seeing the required positive improvements in water quality after years of upland stream restoration. Compounding this is the fact climate variability cannot be ignored. Results indicate that the North Atlantic Oscillation (NAO) has significant wavelet coherence with bottom dissolved oxygen, precipitation, and nutrients. This suggests that current restoration efforts may not be able to keep up with climate variability, and other techniques (restoration or policies) may need to be implemented.

Invasion of Prosopis trees into arid ecosystem alters soil carbon and nitrogen processes and soil trace gases emissions

The invasion of drylands by leguminous mesquite (Prosopis spp.) is frequently associated with increases in the soil organic carbon (C) and nitrogen (N) pools. These increases stimulate soil microbial activity and accelerate soil C and N cycling. However, the impact of mesquite invasion on soil biogeochemistry, especially the emission of trace gases, in an ecosystem with an already established population of N-fixing plants is not well studied. To fill this knowledge gap, we quantified the in-situ soil trace gas emissions and the potential microbial activity in soils under invasive mesquite (Prosopis juliflora) trees (Prosopis), native acacia (Acacia tortilis) trees (Acacia), and in unvegetated soil between trees (Bare soil) on the western shore of the Dead Sea. To account for contributions of spatial and weather variabilities to the emission processes we conducted measurements across two geographic sites, 45 km apart, over two years, both under naturally dry soil conditions and after soil wetting. Before wetting, soil emissions of carbon dioxide (CO2) and nitric oxide (NOx) followed the order: Acacia > Prosopis ≥ Bare soil, while soil nitrous oxide (N2O) emissions were low and uniform across the three habitats. The soil inorganic N concentration, microbial biomass, and water-extractable organic C were significantly higher under the A. tortilis canopies compared with P. juliflora and Bare soil. After wetting, soil trace gases emissions increased up to 66, 1534, and 42 times, for CO2, N2O, and NOx, respectively, and remained higher under the native A. tortilis than under P. juliflora and Bare soil (Acacia > Prosopis > Bare soil). The potential soil microbial activity, however, was similar between the soils under the tree canopies. Our results show that the establishment of invasive leguminous trees increase soil CO2 and gaseous N emissions relative to the Bare soils, but not relative to native leguminous trees.

Examining hydro-morphological modulations in proximity to a drain's estuarine outlet, case study: Kitchener Drain, Northern Coast of Egypt

In recent years, the Kitchener Drain has been affected by littoral erosion and sedimentation at the estuary where its discharge enters the Mediterranean Sea. Several measures have been taken to mitigate the impact of these problems. From 1993 to 2007, four stages of hard protection work were finished, including the construction of groins and detached breakwaters along the drain's eastern and western shores. Work on these projects began in 1992. At the drain outlet, dredging works are still proceeding. Nevertheless, shoreline instability continues even after these efforts. The Coastal Modelling System (CMS) was used to figure out what effect the ongoing hard work had on the erosion and accretion hot spot near the drain's output. The CMS-flow and CMS-wave steering modules are part of the CMS, a two-dimensional model of hydrodynamic circulation. To begin mitigating this effect, we ran the simulation beginning in 2012 and experimented with different calibration settings. After the calibration phase, the research area was subsequently simulated for five years. This study aims to assess the current state of affairs concerning the stabilization of the outflow sedimentation process and the erosion that is taking place on the eastern and western sides. In addition to that, we offered alternate structural modulation scenarios that incorporate both hard and soft structures. We looked at plenty of different possibilities. The scenario with the 600-meter-long jetty and sand nourishment was the most similar to the original coastal characteristics. Regarding a sediment reduction to ‐5706.99 m3 from ‐15321.70 m3 (at benchmark) computed at the outlet zone, this scenario was the most similar to the shoreline's initial appearance. Reducing sediment from ‐133433 m3 (at benchmark) to ‐114512 m3 was also achieved on the western side. Despite this, it was determined that the stability of the coastline would be influenced subtly by this circumstance.

Russia’s Participation in the Development of Transport and Logistics Highways of the EAEU Member States

Aim. An overview analysis of the prospects for trade and economic relations in the EAEU, the SCO countries and other interested states, coupled with interests in the geo-economic and geopolitical Eurasian space in the conditions of artificial escalation of local tensions by the collective West.Tasks. Search and evaluation of optimal routes for the development of traditional and new transport and logistics highways, their branched corridors from the perspective of strengthening economic integration agreements, security and interaction of the Eurasian Union with the SCO countries.Methods. The article uses methodological tools of spatial economics, economic, geographical and geopolitical analysis of the interests of states, analysis and synthesis of interests and synergy of interests of the participating states of global Eurasian projects.Conclusions. The study showed the possibilities of new and old transport magistral (the highway) systems (TMS), both through Kazakhstan and through the development of a unique alternative — the Northern Sea Route (NSR) with the construction of a completely new infrastructure and their maintenance. The issues of TMS on the BAM and Trans-Siberian railway were touched upon. An assessment of alternatives to TMS in terms of cost and time is given. The potential opportunities of the expanding TMS and cargo traffic along the Caspian-Caspian corridor, both overland from the east (Turkmenistan — Kazakhstan — Russia) and the western shore of the Caspian Sea (Iran — Azerbaijan — Russia), as well as along waterways along the same “North — South” corridor, are indicated.Results. An assessment of effective routes has been carried out; strategic objectives have been identified for newly opened transport and logistics highways, which are defined as “new lye routes” through the territories of the EAEU and neighboring interested states (China, India, Pakistan, Afghanistan, Iran, etc.), which gradually plan to enter into closer relations from participating observers relations in the international division of labor.

Sex-based Differences in Fatty Acids and Macro Elements Composition in Garfish, European Barracuda and Anglerfish from Aegean Sea, Türkiye

Background: Fish, owing to its nutritional attributes, serves as a pivotal component of a wholesome diet. The constituents found in fish, specifically macroelements and polyunsaturated fatty acids (PUFA), play a crucial role in promoting human health. This study investigates the fatty acid profiles and macro element contents of economically significant fish species, including garfish (Belone belone), European barracuda (Sphyraena sphyraena) and anglerfish (Lophius piscatorius), with a specific focus on gender-based differences. The research addresses a notable gap in existing literature, providing a comprehensive evaluation of the nutritional quality of these species. Methods: In February 2023, marine fish species, were obtained from the Aegean Sea located between the western and southwestern shores of Türkiye and the eastern shores of Greece. A total of fifteen samples, representing each fish species and gender within the sampling area, were collected for the analysis of fatty acids and macro elements. Result: The findings of this study indicate that, regardless of fish species and gender, the major fatty acids in the SFAs, MUFAs and PUFAs classes were palmitic (C16:0), oleic (C18:1n-9) and DHA (C22:6n-3), respectively. The examined species in this study exhibit average macro element levels. While PUFA, EPA and DHA values meet target levels of content for human health and quality food consumption, achieving these levels minimally implies that the studied species lack a rich fatty acid profile compared to those in prior research. Nonetheless, it is concluded that monitoring seasonal variations is essential for a comprehensive understanding of their fatty acid composition.

Temporal variability of sinkhole hazard illustrated in the western shore of the Dead Sea

AbstractThe growing economic and societal damage caused by sinkhole activity worldwide requires the development of scientifically sound sinkhole hazard assessment approaches. Currently, there is a striking paucity of quantitative sinkhole hazard studies largely related to the incompleteness of sinkhole inventories and the lack of chronological data. Moreover, the probability of occurrence of sinkholes (i.e., sinkhole hazard) is commonly considered as a steady variable, a concept that may lead to significant hazard over- or under-estimates. The extraordinarily high frequency of sinkhole occurrence of the studied sector of the western shore of the Dead Sea has allowed us to explore for the first time the potential temporal variability of sinkhole hazard parameters. Here, we produced six multi-temporal sinkhole inventories with morphometric data between 2005 and 2021 using remote-sensed imagery. The frequency-size relationships generated for successive time intervals with a total of 667 new sinkholes reveal substantial temporal changes in the sinkhole hazard components (i.e., frequency and size). Moreover, the work illustrates that spatial redundancy (sinkholes nested within or intersecting pre-existing ones) can lead to significant hazard overestimates if not considered, especially in areas with high sinkhole density and clustering. This work discusses the limitations of some widely used methods and concepts for sinkhole hazard assessment and illustrates the advantages of detailed multi-temporal mapping for assessing frequency-size relationships and their temporal trends.

Ecological Studies of Saurashtra Coast and Neighbouring Islands: I. Diu Island

The plant ecology of Diu, an island of irregular outline, situated in 20°43' N & 71°02' E and separated from the southern extremity of the peninsula of Saurashtra by a narrow channel on western shore of India is presented in this paper. Several plant communities are grouped into three ecosystems : Rock-strand, Strand and Inland sandy plain. The community type is a sub-division of an ecosystem, that is, it is recognised by the features of both its plant cover and its habitat. Plant communities under each of the three abovementioned ecosystems are described and also analysis of rocks and soils presented in tabular form to study soil features in relation to vegetation.

Polycyclic aromatic hydrocarbons in seawater after the mysterious oil spill of 2019 on the Pernambuco coast, northeast Brazil

In 2019, one of Brazil's most significant environmental disasters occurred, involving an oil spill that directly affected Pernambuco state. Contamination along the coast was evaluated by the quantification of polycyclic aromatic hydrocarbons (PAHs) in fifty seawater samples collected in the summer and winter of 2021. Analysis using fluorescence spectroscopy revealed that for all the samples, levels of dissolved/dispersed petroleum hydrocarbons (DDPHs) were higher than the regional baseline for tropical western shores of the Atlantic Ocean. GC–MS analyses quantified 17 PAHs in the samples, with highest total PAHs concentrations of 234 ng L−1 in summer and 33.3 ng L−1 in winter, which were consistent with the highest risks observed in ecotoxicity assays. The use of diagnostic ratios showed that the coast was impacted by a mixture of PAHs from petrogenic and pyrolytic sources. The results indicated the need for continuous monitoring of the regions affected by the 2019 spill.

STRAW-b (STRings for Absorption length in Water-b): the second pathfinder mission for the Pacific Ocean Neutrino Experiment

Since 2018, the potential for a high-energy neutrino telescope, named the Pacific Ocean Neutrino Experiment (P-ONE), has been thoroughly examined by two pathfinder missions, STRAW and STRAW-b, short for STRAW and STRAW-b. The P-ONE project seeks to install a neutrino detector with a one cubic kilometer volume in the Cascadia Basin's deep marine surroundings, situated near the western shores of Vancouver Island, Canada. To assess the environmental conditions and feasibility of constructing a neutrino detector of that scale, the pathfinder missions, STRAW and STRAW-b, have been deployed at a depth of 2.7 km within the designated site for P-ONE and were connected to the NEPTUNE observatory, operated by Ocean Networks Canada (ONC). While STRAW focused on analyzing the optical properties of water in the Cascadia Basin, STRAW-b employed cameras and spectrometers to investigate the characteristics of bioluminescence in the deep-sea environment. This report introduces the STRAW-b concept, covering its scientific objectives and the instrumentation used. Furthermore, it discusses the design considerations implemented to guarantee a secure and dependable deployment process of STRAW-b. Additionally, it showcases the data collected by battery-powered loggers, which monitored the mechanical stress on the equipment throughout the deployment. The report also offers an overview of STRAW-b's operation, with a specific emphasis on the notable advancements achieved in the data acquisition (DAQ) system and its successful integration with the server infrastructure of ONC.

Каналы озера Каменное: к вопросу о крестьянских гидротехнических сооружениях Карелии

There are a large number of unexplored structures in Karelia related to peasant economic activities. These are mills, storage facilities, barns, hunting traps, paddocks, and roads located outside the boundaries of historical villages. In the paper, we will consider the objects of the Karelian rural water transport infrastructure group – channels. In the absence of good roads in the White Sea Karelia, waterways were the only convenient way to travel between villages throughout the year.The first field study of the channels was carried out by an archaeological expedition of the National Museum of the Republic of Karelia in 2015 on Lake Kamennoe (Kiitehenjarvi) in the Kostomuksha Nature Reserve. Two channels were examined near the village of Shappovaara on the western shore of the lake and the village of Luzhmaguba near the beginning of the Kamennaya River. The first channel (90 m long) was photographed by Finnish photographer K.I. Inha in 1894. There were two wooden crosses and two karsikkos near it and boats passed through it, the second channel (306 m) was probably used for transporting logs during the rafting period. The estimated dating of both structures is the second half of the XIX century. The closest analogies are located on the territory of Finland.

Detecting Shoreline Changes on the Beaches of Hainan Island (China) for the Period 2013–2023 Using Multi-Source Data

This study presents an in-depth analysis of the dynamic beach landscapes of Hainan Island, which is located at the southernmost tip of China. Home to over a hundred natural and predominantly sandy beaches, Hainan Island confronts significant challenges posed by frequent marine natural disasters and human activities. Addressing the urgent need for long-term studies of beach dynamics, this research involved the use of CoastSat to extract and analyze shoreline data from 20 representative beaches and calculate the slopes of 119 sandy beaches around the island for the period from 2013 to 2023. The objective was to delineate the patterns of beach evolution that contribute to the prevention of sediment loss, the mitigation of coastal hazards, and the promotion of sustainable coastal zone management. By employing multi-source remote sensing imagery and the CoastSat tool, this investigation validated slope measurements across selected beaches, demonstrating consistency between the calculated and actual distances despite minor anomalies. The effective use of the finite element solution (FES) in the 2014 global tidal model for tidal corrections further aligned the coastlines with the mean shoreline, underscoring CoastSat’s utility in enabling precise coastal studies. The analysis revealed significant seasonal variations in shoreline positions, with approximately half of the monitored sites showing a seaward progression in summer and a retreat in winter, which were linked to variations in wave height. The southern beaches exhibited distinct seasonal variations, which contrasted with the general trend due to differing wave impacts. The western and southern shores showed erosion, while the northern and eastern shores displayed accretion. The calculated slopes across the island indicated that the southern beaches had steeper slopes, while the northern areas exhibited more pronounced slope variations due to wave and tidal impacts. These findings highlight the critical role of integrated coastal management and erosion control strategies in safeguarding Hainan Island’s beaches. By understanding the mechanisms driving seasonal and regional shoreline changes, effective measures can be developed to mitigate the impacts of erosion and enhance the resilience of coastal ecosystems amidst changing environmental conditions. This research provides a foundational basis for future efforts aimed at the sustainable development and utilization of coastal resources on Hainan Island.

The range of ice thrusts and ice piles as reflected by ice scars on trees growing on the shores of coastal lagoons: The case of the Szczecin Lagoon

We studied the phenomena associated with the thrusting of ice onto the shore of the Szczecin Lagoon based on the occurrence of tree ice scars. The measurements concerned mostly the maximum height, length and width of ice scars on trees, and the distance of these trees from the shore in the period 2017–2022. It was observed that sheets of ice advanced up to 64 m inland, and piled to form hummocks reaching up to 4.3 m above the water level. These maximum values occurred mostly on eastern shores, which is where the highest numbers of damaged and broken trees were observed. This should be associated with the strongest and most frequently occurring wind blowing from the western direction in the winter-spring period. To the contrary, the lowest number of damaged trees were observed on the western shore. This is due not only to the lower frequency of wind blowing from the east, and the associated cooling (Ta < 0°C) and ice cover stabilization, but also due to the presence of extensive reed belts. Our results enable an indirect insight into the ice phenomena dynamics, especially in areas lacking systematic ice observations. Similar conclusions may be extended for all the sheltered basins as lakes or lagoons.

The impact of global climate changes on trace and rare earth elements mobilization in emerging periglacial terrains: Insights from western shore of Admiralty Bay (King George Island, Antarctic)

In the rapidly changing climate, the biogeochemical behaviours of trace elements and Rare Earth Elements (REEs) in emerging periglacial environments assumes profound importance. This study provides pivotal insights into this dynamic by investigating the Antarctic's response to global climate change. The bedrock of King George Island is rich in REEs, with the presence of trace metals (TEs), with the highest concentrations of metals found in ornithogenic soil (∑REE 84.01–85.53 mg∙kg−1 dry weight). REEs in the studied soil, found mainly in igneous rocks, as is indicated by the positive correlation of these elements with sodium and calcium. The TEs released as a result of weathering are leached by water flowing down local watercourses to Admiralty Bay, as indicated by the decreasing results of ∑REE = 11.59 μg∙dm−3 in watercourse water, ∑REE = 1.62 μg∙dm−3 in watercourse pools and ∑REE = 0.66 μg∙dm−3 in the water of Admiralty Bay at the outlet of the watercourse. Water originating from the melting of snow on the glacier also carried REEs (∑REE = 0.14 μg∙dm−3), a fact which suggest the further influx of these elements from atmospheric deposition. The Prasiola crispa turned out to be the most susceptible to the accumulation of REEs (∑ 80.73 ± 5.05 μg g−1) and TEs, with the exception of chromium and zinc, whose concentrations were found to be at their highest in Deschampsia antarctica. In Usnea antarctica, Xanthoria candelaria, and Ceratodon purpureus and Politrichastrum alpinum, a dominant role in the accumulation of REEs was played by HREEs. The determined enrichment factor (EF) indicates that the soil cover is a source of REEs (EFAlgae for ∑REE = 5.07; EFLichen for ∑REE = 6.65; EFBryophyta for ∑REE = 5.04; EFVascular for ∑REE = 4.38), while Ni, As and Pb accumulated in plants may originate from other sources than the soil.

Combined Genomic and Imaging Techniques Show Intense Arsenic Enrichment Caused by Detoxification in a Microbial Mat of the Dead Sea Shore

AbstractMicrobial mats and microbialites are essential tools for reconstructing early life and its environments. To better understand microbial trace element cycling, a microbial mat was collected from the sinkhole systems of the western shores of the Dead Sea, a dynamic environment exhibiting diverse extreme environments. Intense arsenic enrichment was measured (up to 6.5 million times higher than current concentrations in water, and 400 times the bulk concentration in the mat). Arsenic was found predominantly as As(V) in organic molecules, as shown by XANES spectra and high‐resolution elemental mapping. Arsenic cycling genes obtained from metagenomic analysis were associated with arsenic detoxification, supporting an active mechanism of As(V) uptake, As(III) efflux and organoarsenic accumulation in the extracellular polymeric substances (EPS) of the mat. Thus, we propose that such localized As enrichment can be attributed to a transient increase in As(V) concentrations in the circulating subsurface water of the Dead Sea shore and its subsequent incorporation into organoarsenic molecules through microbial detoxification processes. Our data set supports the possibility of metalloid enrichment recorded in very localized facies due to rapid geogenic fluctuations in the chemistry of the water flowing over a biofilm. In this context, this example calls for caution in interpreting metal(loid) enrichment in organic matter‐rich layers and microbialites of Paleoproterozoic origin. Arsenic signatures in Precambrian organic matter and carbonate rocks may host biosignatures, including evidence for extracellular polymeric substances, As‐binding and detoxification processes, without supporting arsenotrophy. However, they provide clues to better assess the paleoenvironmental conditions at the time of microbial mat formation.

Discontinuous transtensional rupture during the Mw 7.2 1995 Gulf of Aqaba earthquake

The Gulf of Aqaba earthquake occurred on 22 November 1995 in the Northern Red Sea and is the largest instrumentally recorded earthquake in the region to date. The event was extensively studied during the initial years following its occurrence. However, it remained unclear which of the many faults in the gulf were activated during the earthquake. We present results from multi-array back projection that we use to inform Bayesian kinematic rupture models constrained by geodetic and teleseismic data. Our results indicate that most of the moment release was on the Aragonese fault via left-lateral strike slip and shallow normal faulting that may have been dynamically triggered by an early rupture phase on the Arnona fault. We also identified a predominantly normal fault-segment on the eastern shore of the gulf that was activated in the event. We dismiss the previously proposed hypothesis of a co-seismic sub-event on the western shore of the gulf and confirm that observed deformation can be rather attributed to post-seismic activity. In conclusion, the gulf shows many signs of active tectonic extension. Therefore, more events close to the shorelines are to be expected in the future and should be considered conducting infrastructure projects in the region.

The Spatiotemporal Variation and Historical Evolution of Heavy Metal Pollution in Sediments from the Pearl River Estuary, China

Many tributaries of the Pearl River carry large amounts of terrestrial pollutants into estuarine areas. Heavy metals accumulate in estuarine sedimentary environments, and coupled and changing biogeochemical processes occur in estuarine areas. The results of this study showed that the heavy metal contents in the sediment were the highest near the confluence of the Humen and Jiaomen outlets in 2005 and 2019; they were the second-highest near the remaining outlets, and gradually decreased toward the lower reaches, with high contents on the western shore and low contents on the eastern shore. The heavy metal pollution mainly originated from the Pearl River runoff. The historical evolution of heavy metals in the Pearl River Estuary (PRE) effectively reflected the impacts of pollutant inputs from the river basin as well as industrial and agricultural production and anthropogenic activities in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). In 2019, the surface sediments were not contaminated with Hg, and the Pb and Zn contents decreased significantly, indicating significant advances in environmental management; however, the Cu and Cd levels still indicated heavy pollution level in the upper reaches.

Results of synchronous measurements of the content of nitrogen and sulfur oxides in the atmosphere of Southern Baikal in July 2023

The paper presents the results of synchronous measurements of the content of small gas impurities at the three atmospheric monitoring stations located on the shore of Southern Baikal, July 2023. The measurements were carried out using automatic gas analyzers, which enabled to obtain data on the content of sulfur and nitrogen oxides in the atmospheric air with high temporal resolution. The studies showed that in spite of a small distance between the observation stations, the fluctuations of concentrations of small gas impurities on different shores of Southern Baikal occur independently of each other. We suggested that an increase of nitrogen and sulfur oxide concentrations on the western shore in summer is probably correlated more with the impact of regional thermal power plants (TPP) and on the eastern shore with the orographic features of the southern basin of the lake and local sources. The influence of meteorological conditions on the content of gas components in the atmosphere of Southern Baikal was estimated using multivariate statistical methods, namely, NWR and PSCF.

Coupling and de-coupling of the El Niño Southern Oscillation to the supply of larval fishes to benthic populations in the Hawaiian Islands.

Several recent high intensity ENSO events have caused strong negative impacts on the adult phases of foundational species in coral reef ecosystems, but comparatively little is known about how climatic variables related to recent ENSOs are impacting the supply of larvae to benthic populations. In marine fishes and invertebrates, reproductive adults and planktonic larvae are generally more sensitive to environmental variability than older, non-reproductive adults. Further, the transport of larvae in ocean currents may also be strongly ENSO dependent. The interactions between the dynamics of larval survivorship and larval transport could lead to population bottlenecks as stronger ENSO events become more common. We tested the predictions of this hypothesis around the Main Hawaiian Islands (MHI) by constructing a correlation matrix of physical and biological time series variables that spanned 11 years (2007-2017) and multiple ENSO events. Our correlation matrix included four types of variables: i. published ENSO indices, ii. satellite-derived sea surface temperature (SST) and chlorophyll variables, iii. abundance and diversity of larval fishes sampled during the late winter spawning season off Oahu, and iv. abundance and diversity of coral reef fish recruits sampled on the western shore of the Big Island of Hawaii. We found that the abundance and diversity of larval fishes was negatively correlated with the Multivariate El Niño Index (MEI), and that larval variables were positively correlated with measures of fall recruitment (September & November), but not correlated with spring-summer recruitment (May & July). In the MHI, SST variables were not correlated with the MEI, but two successive El Niño events of 2014-15 and 2015-2016 were characterized by SST maxima approaching 30°C. Two large pulses of benthic recruitment occurred in the 2009 and 2014 recruitment seasons, with > 8000 recruits observed by divers over the summer and fall months. Both events were characterized by either neutral or negative MEI indices measured during the preceding winter months. These patterns suggest that La Niña and the neutral phases of the ENSO cycle are generally favorable for adult reproduction and larval development in the spring and summer, while El Niño phases may limit recruitment in the late summer and fall. We hypothesize that episodic recruitment during non-El Niño phases is related to favorable survivorship and transport dynamics that are associated with the formation of pairs of anticyclonic and cyclonic eddies on the leeward sides (western shores) of the Main Hawaiian Islands.