Stable Isotopes - Science topic

Playa-lakes are highly sensitive to hydroclimate changes, which are often reflected in their sediments. In this study, we investigate the paleohydrological evolution of the Fuente de Piedra playa-lake (southern Spain), in connection to climate fluctuations during the Late Pleistocene-Holocene transition. Stable isotopes (δ18O and δ2H) of gypsum hyd...

Carbonate spherulites from hydrocarbon-derived thrombolites are newly described from a Lower Cretaceous cold seep in the Outer Carpathians (Poland). These spherulites were studied using various techniques, including optical microscopy, cathodoluminoscopy, SEM-EDS, Raman spectroscopy, EPMA, and carbon and oxygen stable isotopic analyses. Spherulites...

Understanding fish life history is essential for effective management of fisheries, but continuous tracking over lifetime temporal scales can be difficult. Fish otoliths contain a natural biogeochemical record of ambient environmental conditions and habitat use over such scales. However, ecological interpretations of these elemental compositions ca...

Drought disrupts nitrogen (N) cycling by simultaneously reshaping N dynamics in leaves and soils, potentially limiting plant growth and ecosystem productivity. Understanding how drought affects these coupled dynamics in forests is crucial for predicting future carbon–nitrogen interactions amid declining global N availability. Based on a long‐term e...

Later Stone Age (Iberomaurusian) hunter-gatherer groups in northwestern Africa appear to have experienced a major reorganization of land-use strategies and settlement dynamics around 15–13 cal ka BP, which broadly corresponds to the globally recognized Greenland Interstadial 1 (Bølling-Allerød) climate interval. However, our understanding of the lo...

Biogeochemical changes associated with Deccan volcanism and their potential link to the K/Pg extinction event are still debated in Palaeoclimate research. Contemporary terrestrial organosedimentary deposits are important archives for understanding the perturbation in the biogeochemical cycling during this critical episode in Earth's history. Here,...

Understanding the oceanic cycling and transport of the climatically relevant greenhouse gas, nitrous oxide (N2O), is imperative for interpreting how it could change with environmental conditions. We studied the distributions of N2O concentration and stable isotopes under biogeochemically and physically diverse environments along the GEOTRACES GP16...

The mycoheterotrophic nutritional mode, characterized by the acquisition of fungal-derived carbon by plants, has long captivated botanists and mycologists. Recent stable isotope analyses of fungal pelotons isolated from roots have advanced our understanding of this nutritional strategy; however, concerns remain regarding potential isotopic biases,...

Stable isotopes of atmospheric nitrate (NO3-) are valuable tools for tracing nitrogen sources and processes; however, their signals in ice core records are often disrupted by postdepositional processes. The ice core from the southeastern Dome (SE-Dome) in Greenland is a potential record of variations in atmospheric chemistry that has experienced a...

Conducting morphometric measurements on subfossil chironomid head capsules will be key to uncovering the long-term mechanisms of body size variations of aquatic invertebrates. However, the wider use of subfossil chironomids in phenotypic plasticity reconstructions has been limited by three main methodological gaps regarding the influence of laborat...

Food web interactions are generally considered to be size‐structured and occur at the individual or group level within species, yet many ecological models and tests of theory assign species‐level values to define trophic position or niches. Such studies ignore potential ontogenetic or within‐species size‐based changes in consumer behaviour and trop...

The effect of arbuscular mycorrhizal fungi (AMF) on decomposition can be regulated by their role in plant nitrogen acquisition due to their obligate biotrophic lifestyle. However, few studies have addressed the relationship between these two processes. We conducted an experiment using mycorrhizal‐defective mutants and wild‐types of two plant specie...

Water use strategies reflect the ability of plants to adapt to drought caused by climate change. However, how these strategies change with stand development and seasonal drought is not fully understood. This study used stable isotope techniques (δD, δ18O, and δ13C) combined with the MixSIAR model to quantify the seasonal changes in water use source...

Over the past century, drylands have undergone significant landscape transformations. Abandonment of traditional crops and pastures led to development of extensive afforestation programs with conifers, which often lacked an ecologically sound orientation, raising concerns on their potential consequences on recipient ecosystems. Forest streams heavi...

Groundwater contamination from legacy mining activities is a significant environmental concern, particularly in karst regions with vulnerable aquifers. This study investigates the isotopic composition of groundwater sulfates in a former mining area (Apuan Alps, Italy) to identify contamination sources and assess aquifer vulnerability. Sulfur and ox...

Magnesium, an essential biological element, exhibits stable isotope compositions that reflect organisms' dietary structure and trophic position. Accordingly, magnesium isotope analysis offers valuable potential for reconstructing the ecological niches of modern and ancient mammals within food webs. This study analyzes the magnesium isotope composit...

Establishing interlaboratory compatibility among measurements of stable isotope ratios of atmospheric methane (δ13C-CH4 and δD-CH4) is challenging. Significant offsets are common because laboratories have different ties to the VPDB or SMOW-SLAP scales. Umezawa et al. (2018) surveyed numerous comparison efforts for CH4 isotope measurements conducted...

This study explores the potential of stable carbon isotope (δ¹³C) composition of ambient carbonaceous aerosols in assessing the nature and apportionment of their sources. As part of the CarbOnaceous AerosoL Emissions, Source apportionment & ClimatE Impacts (COALESCE) network, δ¹³C measurements (n = 1120) were conducted on aerosol samples collected...

Subsurface flow in preferential pathways in soils may transport water more rapidly than the soil matrix, which may be quickly activated during precipitation events and enhancing infiltration or interflow. Vertical pathways are particularly important for runoff generation. However, identifying these pathways is challenging because traditional method...

Carnivorous and parasitic plants have captured attention not only for public but also for researchers for centuries. Instead of absorbing inorganic nitrogen from soils, they can obtain some or most of their nutrients from heterotrophic organisms. With such special strategies of ‘carnivory’ and ‘parasitism,’ they indeed successfully survive in oligo...

Many headwater catchments contain non-perennial streams that flow only during wet conditions or in response to rainfall events. The onset and cessation of flow result in a dynamic stream network that periodically expands and contracts. The onset of flow can flush sediment and nutrients from previously dry streambeds and enhance the rates of carbon...

Characterization of water-rock-microbe interaction in the subterranean estuary of a temperate high-energy beach (Northern Speiekroog island) by the analyses of the stable isotope composition of water, sulfate, and in particualr dissolved inorganic carbon, and the micro-phase analysis of minerals in the aquifer. Fresh-salt water mixing dominates the...

Trophic interactions operate across the lifetime of an individual organism, yet our understanding of these processes is largely limited to a single life stage or moment in time. Management and conservation implications of this knowledge gap are particularly important, given the mounting number, spread, and ecological impacts of invasive species. Bi...

Microbial communities living on plant leaves can positively or negatively influence plant health and, by extension, can impact whole ecosystems. Most research into the leaf microbiome consists of snapshots, and little is known about how microbial communities change over time. Weather and host physiological characteristics change over time and are o...

This project involves continuous measurements of stable isotope composition (2 H, 18 O) in rainfall in Bangui. The aim is to establish a local meteoric line, determine the effects influencing isotopic composition and assess the potential of these measurements for understanding the humid atmospheric processes prevalent in this geographical area. Ove...

The mid-Cretaceous Kem Kem beds of Morocco contains an overabundance of giant theropod dinosaurs, including Spinosaurus and Carcharodontosaurus—both longer than Tyrannosaurus. Compared to modern and other Mesozoic continental ecosystems, in which herbivores represent most of the vertebrate biomass, predators are overrepresented in the mid-Cretaceou...

The effects of global warming are most pronounced at high latitudes and are a threat to primary productivity patterns and, in particular, to sea ice algae. Here, we investigated the importance of ice algae in the diet of megabenthic organisms belonging to several feeding guilds across several locations in the Canadian Arctic characterised by differ...

Information on seabird diet is key to understanding their ecological role in the marine food web. The Mediterranean Sea is a biodiversity hotspot that is experiencing a series of growing threats, including overfishing and climate change. The Scopoli’s (Calonectris diomedea) and Yelkouan shearwaters (Puffinus yelkouan), two marine predators in the r...

© [Martin T. Bosnev] — Shared under Creative Commons BY 4.0 My sincere desire is to wish all future clinical trials on this subjects to be conducted only on human volunteers or on a tissue cultures aka bio-chips - search that term in the TED talks, also TED talks in Youtube !!!!!!! +Something New that it is NOT in the text below yet!! : Potential...

Typically used to reconstruct diets and migration histories, isotope ratios in human tissues also reflect physiological states associated with health and stress. The publication in 2013 of a paper in the American Journal of Human Biology reviewing such cases has been widely cited. This article revisits this topic and reviews key research exploring...

Mustelus lunulatus is a species that is part of the artisanal fishery of elasmobranchs in Baja California Sur (B.C.S.), in addition to being a member of the region’s food web. Local fisheries can be affected by various oceanographic phenomena such as the Blob and El Niño events. These oceanographic phenomena can affect species composition along the...

Maple trees repair cold‐induced embolism by generating positive stem pressure during their leafless state, altering sap transport in ways that remain poorly understood. This xylem pressure also drives sap exudation, enabling maple sap harvest for syrup production. This study investigates water source dynamics in leafless maples in early spring and...

Coral reefs receive both passive and active nutrient subsidies, supplied via oceanographic processes and animal-mediated transfer, which can bolster reef productivity and resilience to disturbance. We examined the relative importance of these two pathways across lagoonal and seaward reefs, reefs of different depths, and those around islands either...

The proton capture cross-section of the least abundant proton-rich stable isotope of cadmium, ¹⁰⁸Cd (natural abundance 0.89%), has been measured near the Gamow window corresponding to a temperature range of 3–4 GK. The measurement of the total capture reaction cross-section of ¹⁰⁸Cd(p,γ)¹⁰⁹In was conducted using the activation technique with 66.3%...

The expansion and development of aquaculture activities in the Tam Giang–Cau Hai lagoon system, including the Thuy Tu and Cau Hai lagoons, has generated waste that impacts the natural environment. This research focused on assessing the isotopic compositions of carbon and nitrogen in suspended organic matter within the aquaculture ponds and surround...

Long-lived bigmouth buffalo (Ictiobus cyprinellus) are declining and a species of special concern in central Canada whose densities may be impacted by invasive common carp (Cyprinus carpio). In addition, the bigmouth buffalo is a culturally important species for the File Hills Qu’Appelle Tribal Council Member First Nations, who have harvested them...

The biogeochemistry of Cr and its cycling in Earth's surface environments is reviewed. A synthesis and critical evaluation of the major processes controlling Cr mobility and isotope composition (δ⁵³Cr) is presented, taking a source to sink view beginning with Cr mobilization from Earth's crust. Transport and cycling in inland waters and input to th...

Aims Alley-cropping systems (ACS) often increase soil organic matter and microbial biomass with unknown effects on the decomposition of harvest residues. The central objective of the current field study was to address microbial decomposition processes in two distinct ACS. Methods Litterbags with ¹⁵N labelled C4-plant maize (Zea mays) root or stalk...

Drought frequency and severity intensify with climate change, challenging many Mediterranean cities to face securing sustainable water supplies. In this context, groundwater emerges as a key but often overlooked resource, particularly in urban areas historically reliant on external drinking water systems. This study provides a comprehensive hydroge...

Caves provide unique access to deeper levels of the Critical Zone (CZ), and speleothems formed within caves preserve dateable records of past CZ process. This study used a combination of modern cave climate monitoring, dripwater sampling, and geochemical investigation of speleothem records to consider how the mountain CZ in part of Utah, USA has ch...

Background One of the best-studied subjects in the area is gold mineralization, and researchers have focused on the veins, their direct weathering products, or fluid inclusion analyses. Abu Khusheiba gold deposits in Jordan were characterized as epithermal deposits, and the wadi sediments below were investigated in some studies. Although epithermal...

Climate change and resource exploitation in the Southern Ocean are important anthropogenic pressures on Antarctic food webs. Understanding the eco-functional roles of Antarctic communities is essential for ecosystem management and conservation. Amphipods are among the most dominant and ecologically important benthic taxa in the Southern Ocean. The...

Our knowledge about climate change is based on the availability of climate data from both the present and the past. Accurate reference data are essential for improving Earth System Models, which help us to analyse and predict climatic developments with greater accuracy. In this context, subfossil landsnail shells and their stable isotope compositio...

Our understanding of the role of tropical lakes in regional carbon budgets remains hampered by a lack of data covering the vast diversity of lake types and settings. Here, we provide a first comprehensive survey of the carbon (C) biogeochemistry of the Lake Alaotra system, a large shallow lake (surface of 200 km² and maximum depth of 2 m) surrounde...

Mass spectrometry-based proteomics enables comprehensive characterization of protein abundance, function, and interactions. Label-free approaches are simple to implement but challenging to scale to thousands of samples per day. Multiplexed techniques, such as plexDIA, can address these limitations but remain restricted by the lack of mass tags opti...

A pesar de los numerosos estudios zooarqueológicos en Pampa occidental-Patagonia, los registros de perros son escasos y, por lo tanto, es limitado el conocimiento del vínculo que tuvieron con las sociedades cazadoras-recolectoras. Las evidencias arqueológicas en períodos prehispánicos indican que estos cánidos desempeñaron roles como animales de co...

Understanding individual variations in animal behavior is crucial for ecology, evolution, conservation, and wildlife management. However, traditional bio‐logging methods have often impeded the reconstruction of long‐term behavioral patterns in mammals because of cost, battery life, and device size constraints. This study proposes and evaluates a no...

The closure of mining operations presents significant environmental challenges for groundwater protection and sustainable closure planning. Fractured and altered aquifers, which supply drinking water to nearly half the world’s population, are vulnerable to disruptions caused by mining. This study investigates groundwater flow and contaminant dynami...

The quality of rice is closely related to its planting mode. The rice produced in rice–crab co-cultivation fields often enjoy higher prices and consumption enthusiasm than traditional rice due to the use of fewer chemical inputs, making it a key target of commercial fraud. In this study, multi-element, stable isotope, metabolite analysis techniques...

Dietary restriction (DR), whether applied during adulthood or juvenile stages, extends lifespan across diverse species. However, the mechanisms by which early-life dietary interventions influence adult physiology and longevity remain poorly understood. Here, using Drosophila as a model, we demonstrate that protein restriction during the larval stag...

In this study, the spatial variations in total organic carbon (TOC), stable carbon isotopes (δ¹³Corg), C/N ratios, and nitrogen isotopes (δ¹⁵Norg) in East Sea sediments are examined to elucidate the sources, preservation, and diagenetic processes of organic matter. To this end, surface sediment samples were collected from the coastal regions of the...

Coastal seabirds are valuable indicators of ecological change in nearshore marine systems impacted by human activities. This study examined how human population growth and urban expansion have influenced the long-term dietary patterns of karoro (southern black-backed gull Larus dominicanus) in Auckland, Aotearoa | New Zealand. Specifically, we asse...

Seabirds are responsible for transporting marine material to oceanic islands, and attempts are being made to restore their function on many islands where they have become extinct. However, little is known about the original island ecosystems prior to disturbance. Minamiiwoto, located in the Ogasawara Islands, is an uninhabited oceanic island that r...

The blacktip grouper (Epinephelus fasciatus) is commercially important and serves as the top predator in reef ecosystems. Understanding its dietary habits is crucial for understanding its ecological role and informing conservation strategies. In this study, we investigated the dietary composition and feeding ecology of E. fasciatus to assess potent...

The Cochin backwater is one of the most dynamic estuaries, strongly influenced by seasonal river runoff and seawater intrusion. This study explores the relationship between monsoonal rains, salinity, and stable isotopic composition (δ¹⁸O and δ¹³C) to estimate the contribution of freshwater fluxes at different seasonal intervals for the Cochin Backw...

The marine ecosystems of the Svalbard archipelago are now propelled towards a new climatic state owing to the ongoing “Atlantification” process. Fjords represent valuable natural laboratories hosting both local and advected populations of zooplankton. Our goal was to study life‐history traits of two Calanus species (C. glacialis and C. finmarchicus...

What kind of waste from nuclear reactions that do not exist in nature could there be? Let us simply assume for a moment, without any explanations, although they are given in other preprints, the unimaginable. Let there is a mixture of different atoms inside the Earth, in which any two identical atoms, when brought together sharply to the minimum po...

Introduction Despite their size, relatively passive behavior, and commercial significance, knowledge of the behavioral ecology of whale sharks remains limited. The difficulty of tracking individual animals at sea encourages the use of retrospective biochemical approaches such as stable isotope analysis. Methods Whale sharks at Mafia Island in Tanz...

Aridity can exacerbate threats to endemic biodiversity, and arid intervals during the last couple of millennia may have contributed to endemic large herbivore extinctions on Madagascar. However, regional palaeoclimate records spanning multiple millennia are limited, and the tolerance of extinct taxa to past water scarcity is poorly known. To infer...

Hydrogen and oxygen stable isotopes are widely used as tracers of the water cycle, and surface water is an integral part of the water cycle. Compared with other waterbodies, surface water is more susceptible to different natural and anthropogenic factors, and an accurate understanding of surface water changes is of great significance in ensuring re...

Ecologists seek to understand the ways that human activities are altering the structures and processes that support biodiversity and nature's contributions to people. Food web research at the interface of community and ecosystem ecology is promising in this regard. An industry of studies has utilized stable isotopes in recent decades to rapidly cha...

Here, the trophic ecology of four mid-trophic level fishes is described for an Arctic coastal marine habitat near Iqaluit, Nunavut. Arctic charr (Salvelinus alpinus), Arctic cod (Boreogadus saida), Fish Doctor (Gymnelus viridis), and sculpins (Cottidae) diet and feeding strategies were estimated using gut content; dietary niches were compared using...

Migratory animals often transport allochthonous materials, energy or organisms from donor to recipient ecosystems, thereby affecting the dynamics of consumers, communities and ecosystems in the recipient systems. The biomass of migrants is commonly assumed to be equal to that of the allochthonous materials they transport, with the inherent assumpti...

Understanding variations in the routes by which wild animals gain and lose water is challenging, and common methods require longitudinal sampling, which can be prohibitive. However, a new approach uses Δ′¹⁷OBW (Δ′¹⁷O of animal body water), calculated from measurements of δ′¹⁷O and δ′¹⁸O in a single sample, as a natural tracer of water flux. Δ′¹⁷OBW...

We propose a reinterpretation of the origin and nature of the cosmic microwave background (CMB) within a Quantized Gravitational Emission Model, with our previous assumption that photons do not lose energy through space propagation. Contrary to the standard ΛCDM cosmology, which interprets the CMB as a relic of the Big Bang, our model treats the Un...

Fluid infiltration along seismically‐active faults and fluid‐rock interaction influence the mechanical behavior of faults. Nevertheless, how fluid infiltration and fluid‐rock interactions evolve at seismogenic depths with fault slip accumulation remain poorly constrained in the geological record. We used hydrogen and oxygen isotope geochemistry to...

Stable isotopes have frequently been used to study metabolic processes in live cells both in vitro and in vivo. Glutamine, the most abundant amino acid in human blood, plays multiple roles in cellular metabolism by contributing to the production of nucleotides, lipids, glutathione, and other amino acids. It also supports energy production via anapl...

In this study, we examined the major sources of particulate organic matter (POM) in the Godavari River during high flow and low flow periods, to understand the impact of excess nitrogen (N)-fertilizers used in agricultural fields. δ¹³C of particulate organic carbon (POC) and δ¹⁵N of particulate nitrogen (PN), elemental carbon (C) to N ratio and POC...

Predictions for the southwestern US with warming often suggest increased aridity. We investigate the sedimentary record of the Miocene Climate Optimum and Transition (MCO and MCT; ∼17–14 Ma) in northern New Mexico to understand the impact of warmer global temperatures and higher pCO2 on southwestern US hydroclimate. The MCO and MCT comprised a glob...

Lake ecosystems are affected globally by climate warming and anthropogenic influences. However, impacts on boreal lake ecosystems in eastern Siberia remain underexplored. Our aim is to determine if shifts in diatom assemblages in a remote lake in eastern Siberia are related to climate warming, similar to observations in temperate regions, while als...

Precipitation fluctuations strongly influence biomass production and its stability of terrestrial ecosystems. However, our understanding of the extent to which plant communities adjust their water‐use strategies in response to non‐growing season precipitation variations remains limited. Our 5‐year snow manipulation experiment in a semi‐arid grassla...

The Qilian Mountains are an important ecological security barrier in the northwest China and a major water supply area for the Hexi Corridor. It is of great significance to study their hydrological processes. Based on the stable isotope values of precipitation, soil water and groundwater in the subalpine shrub zone of the eastern Qilian Mountains f...

Iron is a key micronutrient for marine biota and potentially one of the main drivers of ocean feedback to changing climate. There is however no consensus on the relative role of different external iron sources to the ocean, hampering our ability to predict how the oceanic iron cycle and biological carbon pump will react to climate change. For the l...

Energy deficit is a potent physiological stressor that has shaped human evolution and can improve lifespan and healthspan in a wide range of species. Preserving locomotive capacity was likely essential for survival during the human hunter-gatherer period but surprisingly little is known about the molecular effects of energy deficit on human skeleta...

Zinc is a critical micronutrient that plays multifaceted roles in oxidative stress management, lipid metabolism, pancreatic function, and liver health, which are all closely interconnected with obesity. Maintaining adequate zinc levels is essential for overall metabolic health and proper functioning of these vital systems. The investigational new d...

Fluoride-enriched geothermal groundwater poses chronic health risks (e.g., dental and skeletal fluorosis) through prolonged exposure; nevertheless, hydrochemical-driven factors and the genetic mechanism of fluoride enrichment in such systems remain inadequately identified. This study employed hydrochemical characterization, isotopic tracing, and he...

Introduced fishes for enhancing sport angling tend to be large bodied and of high trophic position, raising ecological concerns on their impacts on prey communities and interactions with native fishes in the same functional guild. The piscivorous pikeperch Sander lucioperca is invasive in several European countries, including in England where it oc...