Impact Of Environmental Changes Research Articles

Hyposalinity elicits physiological responses and alters intestinal microbiota in Korean rockfish Sebastes schlegelii.

Global warming significantly impacts aquatic ecosystems, with changes in the salt environment negatively affecting the physiological responses of fish. We investigated the impact of hyposalinity on the physiological responses and intestinal microbiota of Sebastes schlegelii under the context of increased freshwater influx due to climate change. We focused on the osmoregulatory capacity, oxidative stress responses, and alterations in the intestinal microbiome of S. schlegelii under low-salinity conditions. Our findings revealed compromised osmoregulatory capacity in S. schlegelii under low-salinity conditions, accompanied by the activation of oxidative stress responses, indicating physiological adaptations to cope with environmental stress. Specifically, changes in Na+/K+-ATPase (NKA) activity in gill tissues were associated with decreased osmoregulatory capacity. Furthermore, the analysis of the intestinal microbiome led to significant changes in microbial diversity. Exposure to low-salinity environments led to dysbiosis, with notable decreases in the relative abundance of Gammaproteobacteria at the class level and specific genera such as Enterovibrio, and Photobacterium. Conversely, Bacilli classes, along with genera like Mycoplasma, exhibited increased proportions in fish exposed to low-salinity conditions. These findings underscore the potential impact of environmental salinity changes on the adaptive capacity of fish species, particularly in the context of aquaculture. Moreover, they highlight the importance of considering both physiological and microbial responses in understanding the resilience of aquatic organisms to environmental stress. Additionally, they highlight the importance of intestinal microbiota analyses in understanding the immune system and disease management in fish.

The immediate metabolomic effects of whole-genome duplication in the greater duckweed, Spirodela polyrhiza.

In plants, whole-genome duplication (WGD) is a common mutation with profound evolutionary potential. Given the costs associated with a superfluous genome copy, polyploid establishment is enigmatic. However, in the right environment, immediate phenotypic changes following WGD can facilitate establishment. Metabolite abundances are the direct output of the cell's regulatory network and determine much of the impact of environmental and genetic change on the phenotype. While it is well known that an increase in the bulk amount of genetic material can increase cell size, the impact of gene dosage multiplication on the metabolome remains largely unknown. We used untargeted metabolomics on four genetically distinct diploid-neoautotetraploid pairs of the greater duckweed, Spirodela polyrhiza, to investigate how WGD affects metabolite abundances per cell and per biomass. Autopolyploidy increased metabolite levels per cell, but the response of individual metabolites varied considerably. However, the impact on metabolite level per biomass was restricted because the increased cell size reduced the metabolite concentration per cell. Nevertheless, we detected both quantitative and qualitative effects of WGD on the metabolome. Many effects were strain-specific, but some were shared by all four strains. The nature and impact of metabolic changes after WGD depended strongly on the genotype. Dosage effects have the potential to alter the plant metabolome qualitatively and quantitatively, but were largely balanced out by the reduction in metabolite concentration due to an increase in cell size in this species.

Sedimentary ancient DNA sequences reveal marine ecosystem shifts and indicator taxa for glacial-interglacial sea ice conditions

Sedimentary ancient DNA (sedaDNA) analysis is a promising new approach for reconstructing the impact of past climate and environmental changes on marine paleobiodiversity. By recovering, amplifying, and sequencing taxonomically informative sedaDNA fragments preserved in sediments, it is possible to assess the response of a broad range of eukaryote taxa, including non-fossilizing lineages, to past climate change. Here we present a unique marine derived sedaDNA metabarcoding record, spanning the penultimate glacial-interglacial transition across Marine Isotope Stages 6 to 5d (>135–107 ka) from an Eirik Drift core-site in the Labrador Sea. We identified a range of marine groups including dinoflagellates, diatoms, coccolithophores, chlorophytes, and copepods. There were representatives of primary/secondary producers, grazers, and parasites, which may represent remnants of complex ecosystems and ancient food webs. There were significant biodiversity shifts following the penultimate deglaciation and changing sea ice conditions throughout the Last Interglacial. These shifts reflected the striking increase in community richness during periods of seasonal sea ice and reduction under extensive perennial sea ice cover and open ocean. We identify two potential sedaDNA indicator taxa sequences associated with past seasonal sea ice which are most likely pico-eukaryote representatives of Micromonas and Pyramimonas, both green algae with known sea ice associations in modern ecosystems. Our work demonstrates the importance of high resolution marine sedaDNA metabarcoding for unravelling climate-ecosystem linkages and strengthens the potential of sedaDNA signals for past sea ice reconstructions through indicator sequences.

Climate warming impacts on ringed seal breeding habitat in Svalbard

Global warming is occurring at an accelerated rate in the Arctic compared to other parts of the planet with sea-ice declines being among the most striking manifestations of Arctic climate-related changes. Impacts of ongoing Arctic environmental change have been documented for biota throughout marine ecosystems from protists to top predators. Ice-dependent species with specific habitat needs are particularly vulnerable to the ongoing changes. The ringed seal (Pusa hispida) is an ice-associated Arctic endemic species that gives birth and rests in snow caves built in drifts of snow over holes in the sea ice created and maintained by these seals. In this study we create a snow-on-sea-ice reproductive lair habitat model for ringed seals in the Svalbard Archipelago (Norway), a hot-spot of Arctic warming. We use SnowModel, a physics-based snow distribution and evolution simulation system, as the core for a lair habitat model. The model quantifies snow depth and blowing snow fluxes and also relates these variables to snow availability for seal lair habitat. This was accomplished by developing an ecologically informed snow variable that quantifies potential seal lair habitat availability as a function of blowing snow fluxes. Model simulations were performed for the period September 1987 – August 2021 (34 years) on a 500 m × 500 m grid using a daily time-step. Field observations of snow depth and gridded analyses of sea-ice concentration and near-surface (+10 m) atmospheric forcing (air temperature, relative humidity, precipitation, and wind speed and direction) were incorporated within the model simulations. The results show that both snow depth and potential seal lair habitat have been decreasing in Svalbard for the last two decades. If current trends continue, as expected, ringed seal lair habitat will cease to exist across much of the Svalbard Archipelago in the next decade, putting this important Arctic species at risk of regional extirpation.

Archaeology, climate change and human adaptation in southern Africa: Evidence from Mapela and Little Mapela, southern Africa

In Africa south of the Zambezi River, archaeologists and other experts have long explored the impact of climate and environmental changes to the development of ancient civilizations during the Iron Age (CE 200–1900). Some of the prevailing thought is however still rooted in environmental deterministic models informed by selected ethnographies, stable isotopes and archaeological evidence. For instance, the drought brought by the medieval Little Ice Age is assumed to have collapsed the civilisation at Mapungubwe in the Shashi-Limpopo valley around 1300 CE. And yet, within the wider region, and in similar ecological settings, upstream (Shashi and Upper Limpopo) and downstream civilisations (Lower Limpopo), persisted and thrived through the same climatic challenges. We draw on African cosmologies, resilience theory and archaeological evidence from Mapela and Little Mapela to spotlight adaptation strategies utilised by their inhabitants to build resilience through time. The main conclusion is that even in cases of climatic extremes, humans responded to opportunities and constraints in context specific ways.

Deep learning-based fishing ground prediction for albacore and yellowfin tuna in the Western and Central Pacific Ocean

Tuna is a crucial economic fish species in the ocean, and the research on predicting the location of tuna fishing grounds has always been a key issue in deep-sea fisheries. Tuna, being a highly active fish that moves vertically in the ocean, is extremely sensitive to changes in marine environmental factors. This study aimed to investigate the impact of environmental factors and water depth changes on the accuracy of tuna fishing ground prediction. To achieve this, convolutional neural networks (CNNs) were utilized to train datasets using four key environmental factors - concentration of chlorophyll-a (CHLa), seawater temperature (ST), concentration of dissolved molecular oxygen (Oxy), and seawater salinity (SS) - at various depths ranging from 0 to 300 meters. A binary classification fishing ground prediction model for high and low yield areas of albacore and yellowfin tuna in the Western and Central Pacific Ocean was constructed. The goal was to identify the optimal fishing ground prediction model trained under these conditions and to explore the potential impact of environmental factors and water depth on the prediction accuracy of the model. The data used in this study included information from the Western and Central Pacific Ocean albacore and yellowfin tuna fisheries from 2003 to 2016, along with corresponding environmental data, which were used as the training and validation sets. The fishing data and environmental data from 2017 were then utilized as the test set to develop fishing ground prediction models for the two fish species. The results indicate that using convolutional neural networks to construct fishing ground prediction models is indeed feasible, and spatio-temporal information plays a significant role in optimizing predicting models for tuna fishing ground. Among the models developed for the same fish species using the four marine environmental factors at different depths, the model based on CHLa at each depth was found to be the most effective, while the model constructed using Oxy at the same depth performed the worst. Furthermore, the albacore fishing ground prediction model demonstrated significantly higher efficacy compared to the yellowfin tuna fishing ground prediction model when using the same marine environmental factors. It was also observed that the accuracy of fishing ground prediction models for the same species varied depending on water depth, even when based on the same marine environmental factors. These findings highlight the importance of considering both environmental factors and water depth in predicting tuna fishing grounds accurately.

Variability in zoobenthic blue carbon storage across a southern polar gradient

The seabed of the Antarctic continental shelf hosts most of Antarctica's known species, including taxa considered indicative of vulnerable marine ecosystems (VMEs). Nonetheless, the potential impact of climatic and environmental change, including marine icescape transition, on Antarctic shelf zoobenthos, and their blue carbon-associated function, is still poorly characterised. To help narrow knowledge gaps, four continental shelf study areas, spanning a southern polar gradient, were investigated for zoobenthic (principally epi-faunal) carbon storage (a component of blue carbon), and potential environmental influences, employing a functional group approach. Zoobenthic carbon storage was highest at the two southernmost study areas (with a mean estimate of 41.6 versus 7.2 g C m−2) and, at each study area, increased with morphotaxa richness, overall faunal density, and VME indicator density. Functional group mean carbon content varied with study area, as did each group's percentage contribution to carbon storage and faunal density. Of the environmental variables explored, sea-ice cover and primary production, both likely to be strongly impacted by climate change, featured in variable subsets most highly correlating with assemblage and carbon storage (by functional groups) structures. The study findings can underpin biodiversity- and climate-considerate marine spatial planning and conservation measures in the Southern Ocean.

Middle to late Holocene human societies on the eastern margin of the Eurasian Steppe, and their adaptation to environmental changes

The impact of environmental changes on the development of human societies in the Eurasian Steppe is not well understood over the Holocene timescale. In this study, we have reported the phytoliths, grain size, and weight loss on ignition for an aeolian soil profile in the Liao River Basin at the eastern margin of the Eurasian Steppe. The profiles spanned the middle and late Holocene based on AMS 14C dating. By employing the summed radiocarbon probability distribution of archaeological sites and kernel density analysis, the spatial and temporal distributions of human populations and settlements were investigated in order to analyze the rise and fall of ancient cultures. Our findings indicated that the environment in the Liao River Basin underwent three stages of change. From 6700 to 5400 cal yr BP, the climate was warm and humid. The climate suddenly became cold and dry from 5400 to 4900 cal yr BP. The climate fluctuated, with a general tendency towards cold and dry conditions, from 4900 cal yr BP to 1700 cal yr BP. In addition, human societies in the region underwent significant changes, with rapid agricultural development and population growth in the warm and humid environment of the Middle Neolithic (6700–5000 yr BP). However, during the Late Neolithic (5000–4000 yr BP), the living environment suddenly became cold and dry, which limited the development of human society and drastically reduced its population. Nevertheless, the resilience of human societies continued to increase, and in the Bronze Age (4000–2000 yr BP), even in an overall cold and dry living environment, human societies still developed and their population increased sharply. Changes in the East Asia Summer Monsoon were an important driver of cultural change, and our study emphasizes the complex human-environment interactions that shaped societal development on the Eurasian Steppe.

Modeling coupling impacts of self-healing mechanisms and dynamic environments on systems subject to dependent failure processes

Modern smart products are endowed with the capability to autonomously repair damage from random shocks, thereby highlighting the critical necessity to incorporate this self-healing attribute in reliability assessments. This paper investigates periodically inspected self-healing systems that are exposed to dependent competing failure processes within dynamically evolving environments. The impact of environmental changes is manifested in that both the natural degradation process and the self-healing behavior are governed by distinct laws in varying environments. Explicit formulas for the system reliability and availability are analytically derived using the stochastic process theory, and their correctness is verified by proposed simulation algorithms respectively. Meanwhile, the inspection period is optimized by minimizing the long-run average cost rate. Lastly, a practical example of semiconductor lasers is applied to showcase the application of the presented methods. The sensitivity analysis reveals that increasing the self-healing time threshold or the shock arrival rate can improve the system performance while lowering the long-run average cost rate.

Ecological Grief, Eco-Anxiety and Climate Change; Development and Validation of the Solastalgia Scale

Background: As environmental changes accelerate, psychological impacts such as ecological grief and eco-anxiety become more pronounced. This study focuses on the validation and enhancement of the Solastalgia Scale, originally a unidimensional measure, to assess these complex psychological responses more effectively. Objective: To expand and validate the Solastalgia Scale into a three-dimensional tool encompassing ecological grief, environmental identity, and eco-anxiety, addressing gaps in current research methodologies. Methods: Our methodology involved two main phases: exploratory and confirmatory factor analysis. Initially, exploratory factor analysis was conducted on a purposive sample of 317 participants from Punjab (125 men, 192 women), using Principal Component Analysis, scree plots, and eigenvalues to extract 13 items across three factors. This was followed by confirmatory factor analysis on a new sample of 319 participants (141 men, 178 women) to validate the scale's three-dimensional structure and ascertain model fit indices. Results: The exploratory factor analysis identified three distinct factors, resulting in a 13-item scale. Confirmatory factor analysis confirmed the three-dimensional structure with excellent fit indices (CFI = 0.95, TLI = 0.93, RMSEA = 0.05, SRMR = 0.04). This multi-dimensional approach contrasts with previous research that employed a single-dimensional focus. Conclusion: The revised Solastalgia Scale is a robust tool for assessing the psychological impact of environmental change across multiple dimensions. This scale is instrumental for researchers and practitioners in understanding and mitigating the psychological effects of ecological grief, enhancing resilience and well-being in the face of environmental disruptions.

Which Local Jurisdictions Are Environmental Policy Entrepreneurs? Insights from Israel

Environmental challenges demand local-level engagement. This study delves into the often overlooked entrepreneurial role played by “off-the-map” local authorities in environmental policy. By examining factors influencing Local Environmental Policy Initiatives (LEPIs), including demographic and socioeconomic characteristics, environmental impact, and promotion strategies, we offer a comprehensive analysis. In contrast to studies that spotlight prominent cities, we prioritize the majority—ordinary local governments. Leveraging Israel as a case study, we employ a mix of quantitative and qualitative methods, to validate prior hypotheses suggesting that economically stable and larger authorities tend to initiate more LEPIs. Nevertheless, our research reveals a pro-environmental inclination, even among authorities traditionally not categorized as entrepreneurial. Consequently, smaller and less influential authorities adopt tailored approaches such as problem-framing and terminology strategies to drive environmental initiatives forward. These findings underscore the critical role of local authorities in advancing environmentally sustainable practices, emphasizing their significance in the broader landscape of environmental policy. Notably, they highlight the imperative nature of targeting strategies toward untypical entrepreneurial authorities, to maximize the potential impact of widespread environmental change from the bottom up.

A research on the relationship between landslide area changes and environmental factors in the southern Tibetan plateau

Introduction: Landslides are known to be one of the most frequent types of geological disasters. However, there is not an established method for large-scale, rapid, and high-precision landslide extraction. The quantitative impact of environmental changes on landslide development is also not well understood, which hinders accurate assessments and decision-making in environmental and disaster response. The polar regions, including the Antarctic, the Arctic, and the Tibetan plateau (TP), sensitive to global environmental changes, are significantly affected by global warming. This leads to extensive landslide development, particularly in the southern TP. This research focuses on new landslides in the southern TP, exploring extraction methods and the relationship between landslides and environmental factors.Methods: Utilizing the Google Earth Engine (GEE) and an improved Otsu threshold segmentation algorithm, we processed remote sensing images with 10 m resolution to identify landslide areas. The proposed Normalized Landslide Bare-soil Separation Index (NDLBSI) achieved an 87% pre-extraction accuracy in extracting landslides from Sentinel-2 images from 2019 to 2023. For the pre-extraction results, manual interpretation and correction were carried out, and a model correlating annual landslide changes with environmental factors was established based on least squares multivariate statistical methods.Results: Results show that a significant increase in landslide areas in the southern TP over the past 5 years, correlating with the watershed-wide increase in annual average temperature and vegetation cover, along with a decrease in snow cover area.Discussion: These changes could affect soil and rock moisture, influencing soil stability and landslide occurrence. The study provides valuable insights for large-scale landslide detection and understanding the environmental factors influencing landslides, which is of some significance for landslide hazards early warning.

Distribution and ecology of shallow-water black corals across a depth gradient on Galápagos rocky reefs

AbstractAntipathes galapagensis is a prevalent habitat-forming black coral in subtidal ecosystems of the Galápagos Marine Reserve (GMR). Despite their ecological importance and status as a CITES-regulated order, little is known about their depth distribution, population structure and ecology in the GMR. Surveys were conducted in 2021 and 2022 at 9 sites in the central Galápagos Archipelago to investigate how black coral densities, occupancy, size, habitat utilization, and epizoan overgrowth varied between 2.0 and 20.0 m depth. The shallowest black corals occurred at 3.4 m depth, one of the shallowest occurrences of an Antipathes spp. in the world. Coral density increased with depth, with a maximum density of 5.2 colonies per m2 observed across the depth range surveyed. Occupancy modeling also yielded curves with increasing probabilities of black coral presence with depth at all sites. Colony height increased with depth at 8 out of 9 sites and was positively correlated with coral density at 6 of 9 sites. Overall, 47% of colonies surveyed occupied cryptic habitats and 53% were attached to exposed substrate, but black coral habitat usage patterns varied with depth at 5 of 9 sites. At these sites, colonies on shallower transects (5.0, 10.0 m depth) more frequently displayed cryptic habitat usage while colonies along the deeper transects (15.0, 20.0 m) were more often exposed. In general, coral density, probability of occupancy, height, and exposed habitat utilization increased with depth, while the average degree of overgrowth and number of epibiont taxa were unrelated to depth. Five hypotheses regarding factors potentially limiting the shallow (upper) depth distribution of A. galapagensis—ranging from negative impacts of the physical environment to high predation on exposed substrates—are presented for future testing. These results provide a comprehensive ecological characterization of Galápagos black coral populations that can be used to assess the impact of future environmental change and applied to management decisions for this key marine foundation species in the GMR.

Body and Brain Quality-Diversity in Robot Swarms

In biological societies, complex interactions between the behavior and morphology of evolving organisms and their environment have given rise to a wide range of complex and diverse social structures. Similarly, in artificial counterparts such as swarm-robotics systems, collective behaviors emerge via the interconnected dynamics of robot morphology (sensory-motor configuration), behavior (controller), and environment (task). Various studies have demonstrated morphological and behavioral diversity enables biological groups to exhibit adaptive, robust, and resilient collective behavior across changing environments. However, in artificial (swarm robotic) systems there is little research on the impact of changing environments on morphological and behavioral (body-brain) diversity in emergent collective behavior, and the benefits of such diversity. This study uses evolutionary collective robotics as an experimental platform to investigate the impact of increasing task environment complexity (collective behavior task difficulty) on the evolution and benefits of morphological and behavioral diversity in robotic swarms. Results indicate that body-brain evolution using coupled behavior and morphology diversity maintenance yields higher behavioral and morphological diversity, which is beneficial for collective behavior task performance across task environments. Results also indicate that such behavioral and morphological diversity maintenance coupled with body-brain evolution produces neuro-morpho complexity that does not increase concomitantly with task complexity.

Metabarcoding advances agricultural invertebrate biomonitoring by enhancing resolution, increasing throughput and facilitating network inference

Abstract Biomonitoring of agriculturally important insects is increasingly vital given our need to understand: (a) the severity of impacts by pests and pathogens on crop yield and health and (b) the impact of environmental change and land management on insects, in line with sustainable development and global conservation targets. Traditional entomological traps remain an important part of the biomonitoring toolbox, but sample processing is laborious and introduces latency, and accuracy can be variable. The integration of molecular techniques such as environmental DNA and DNA metabarcoding into insect biomonitoring has gained increasing attention, but the advantages of doing so, the kind of data this can generate, and how easily and effectively molecular analyses can be integrated with the diverse types of entomological traps currently used remains relatively unclear. In this review, we examine how combining DNA metabarcoding with a range of conventional and unconventional entomological sampling techniques can advance biomonitoring in a way that is useful to researchers and practitioners. We highlight some of the key challenges and how to mitigate them, using examples of its integration with different sampling methods from the literature (e.g., interception, pitfall and sticky traps) to demonstrate efficacy and suitability. We discuss how metabarcoding data can be used to infer ecological networks, emphasizing the importance of this as a framework for understanding species interactions and ecosystem functioning for more effective and descriptive biomonitoring. Finally, future advances in biomonitoring are highlighted, alongside recommendations of best practice for researchers both new to and experienced in invertebrate biomonitoring with metabarcoding.

Resource Scheduling Optimization of Fresh Food Delivery Porters Considering Ambient Temperature Variations

In the context of an evolving socio-economic landscape and rising living standards, the online market for fresh products, encompassing fruits, vegetables, meats, dairy, and eggs, has seen substantial growth, necessitating sophisticated logistics for e-commerce home delivery. This study tackles the distinct challenges of fresh product delivery, which demand rigorous adherence to climate conditions and product mix during transport, significantly influencing the operational strategies and scheduling of delivery platforms. To address these challenges, a comprehensive mathematical model was developed to optimize fresh food home delivery scheduling, focusing on reducing spoilage rates and accommodating the dynamic impact of environmental temperature changes. The model posits assumptions of a consistent and ample supply of fresh goods, standard initial quality loss, and efficient porter assignment for multi-category order combinations. It introduces three objective functions, targeting the minimization of fresh food loss, maximization of customer satisfaction, and reduction of distributor costs. The efficacy of the model and its genetic-algorithm-based solution method was assessed through numerical analysis and case studies, illustrating that the model enhances delivery efficiency and service quality across varying temperature conditions. This substantiates the critical role of environmental temperature management in optimizing fresh food delivery, offering a robust framework for advancing logistical operations in the perishable goods sector and ensuring quality and efficiency in fresh food e-commerce delivery.

Rural occupancy in a montane burrowing snake: the importance of thermal and microhabitat resources during the rainy season

Thermal and microhabitat resources are two fundamental requirements that affect the life history of any ectotherm. Furthering our understanding of how reptilian species meet these ecological requirements is crucial for assessing the impact of environmental and anthropogenic changes on populations. Here, we explored some fundamental aspects of the thermal and microhabitat ecology of Conopsis biserialis, a small, burrowing, and endemic earthsnake of central Mexico. The study was conducted during the rainy season in a montane site disturbed by rural activities. The mean field body temperature (Tb) of C. biserialis was 26 ± 0.6 ºC. Field Tb did not differ significantly between sex and development stages. However, we found that Tb was positively correlated with substrate, air, and under-rock temperatures (Ts, Ta, and Tr) in the rural microhabitat. Regression analysis showed that substrate and under-rock temperatures (Ts and Tr) were the parameters that best explained Tb variability in the individuals. The temperature and relative humidity under shelter did not differ significantly among shelter types and/or rock sizes. In addition to these thermal traits, earthsnakes selected and utilized six common biotic and physical elements of the rural microhabitat. Most individuals used high proportions of large and medium rocks for sheltering, and these rocks were selected around crop fences and cleared grasslands where the soil can be either covered with low vegetation or bare. Our results suggest that, during the rainy season, individuals of C. biserialis use and select some biotic and structural resources of the rural microhabitats, and were capable of actively regulating their temperature by using shelters with high values of microclimatic homogeneity.

Productivity of mixed kelp communities in an Arctic fjord exhibit tolerance to a future climate

Arctic fjords are considered to be one of the ecosystems changing most rapidly in response to climate change. In the Svalbard archipelago, fjords are experiencing a shift in environmental conditions due to the Atlantification of Arctic waters and the retreat of sea-terminating glaciers. These environmental changes are predicted to facilitate expansion of large, brown macroalgae, into new ice-free regions. The potential resilience of macroalgal benthic communities in these fjord systems will depend on their response to combined pressures from freshening due to glacial melt, exposure to warmer waters, and increased turbidity from meltwater runoff which reduces light penetration. Current predictions, however, have a limited ability to elucidate the future impacts of multiple-drivers on macroalgal communities with respect to ecosystem function and biogeochemical cycling in Arctic fjords. To assess the impact of these combined future environmental changes on benthic productivity and resilience, we conducted a two-month mesocosm experiment exposing mixed kelp communities to three future conditions comprising increased temperature (+ 3.3 and + 5.3°C), seawater freshening by ∼ 3.0 and ∼ 5.0 units (i.e., salinity of 30 and 28, respectively), and decreased photosynthetically active radiation (PAR, - 25 and - 40 %). Exposure to these combined treatments resulted in non-significant differences in short-term productivity, and a tolerance of the photosynthetic capacity across the treatment conditions. We present the first robust estimates of mixed kelp community production in Kongsfjorden and place a median compensation irradiance of ∼12.5 mmol photons m−2 h−1 as the threshold for positive net community productivity. These results are discussed in the context of ecosystem productivity and biological tolerance of kelp communities in future Arctic fjord systems.

Impact of rapid anthropogenic environmental change on water security in a tropical Andean basin

Rapid anthropogenic environmental change significantly impacts water security (WS) in the Andean highlands, limiting water availability and use. Amidst swift human-induced environmental transformations, discernible trends emerge in increased water demand and heightened ecosystem service valuation. This study examines water usage conflicts in an Andean basin and operationalizes WS using historical analysis for future applications. We focused on WS changes in the Upper Chicamocha River Basin (UCRB), encompassing rural and urban areas. An integrated water security (IWS) framework, with a composite indicator and eight dimensions, is employed to analyze the implications of observed changes over 40 years (1981–2020). Results show a “fair” IWS score 85 % of the time, with 15 % classified as “good”. Evaluation of demand coverage for water usage reveals users benefiting from sufficient water provision (mining, thermoelectric, services, environment, aquaculture, and agriculture), while the industrial and domestic sectors suffer from frequent shortages. Findings emphasize the need for trade-offs in addressing diverse water security outcomes for all users in a changing climate.

New insights into morphological adaptation in common mole-rats (Cryptomys hottentotus hottentotus) along an aridity gradient.

Morphological adaptation is the change in the form of an organism that benefits the individual in its current habitat. Mole-rats (family Bathyergidae), despite being subterranean, are impacted by both local and broad-scale environmental conditions that occur above ground. Common mole-rats (Cryptomys hottentotus hottentotus) present an ideal mammalian model system for the study of morphological variation in response to ecology, as this species is found along an aridity gradient and thus can be sampled from geographically non-overlapping populations of the same species along an environmental longitudinal cline. Using the mass of five internal organs, ten skeletal measurements and 3D morphometric analyses of skulls, we assessed the morphology of wild non-breeding individuals from five common mole-rat populations in South Africa. We found that the body mass and mean relative mass of the spleen and kidneys in arid populations was larger, and individuals from arid regions possessed shorter legs and larger inter-shoulder widths compared to individuals from mesic regions. Additionally, arid populations demonstrated greater skull depth, and shape change of features such as angular processes of the lower jaw than mesic individuals, indicating that these distinct geographic populations show differences corresponding to the aridity gradient, potentially in response to environmental factors such as the variation in food sources found between different habitats, in addition to different soil compositions found in the different regions. Arid populations potentially require a stronger jaw and neck musculature associated with mastication to chew xeric-adapted plants and to dig through hard soil types, whereas mesic populations excavate through soft, looser soil and may make use of their front limbs to aid the movement of soils when digging. Aridity influences the morphology of this species and could indicate the impact of environmental changes on speciation and mammalian skull morphology.