Impact Of Environmental Changes Research Articles

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.

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.

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

AbstractThermal 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.

Physics-informed data-driven model of dehydration reaction stage in the sintering process of ternary cathode materials

The sintering process is the main process that affects the performance of ternary cathode materials. Due to the closed, continuous, and long-term characteristics of the sintering process carried out in a roller kiln, the reaction state including reaction degree, particle size, and etc., of the raw materials cannot be directly obtained through sampling detection, resulting in ineffective temperature control. This article mainly focuses on modeling the dehydration reaction stage of the sintering process to obtain the reaction state of the raw materials. Firstly, a two-sphere model is established based on Newton’s second law and the particle volume conservation equation to describe the relationship between the particle radius and sintering temperature of lithium hydroxide and ternary precursor; Secondly, the chemical kinetic parameters of the dehydration reaction in the two-sphere model are obtained by combining the single heating rate scanning method with the multiple heating rate scanning method; Then, in order to improve the accuracy of the two-sphere model and reduce the impact of external environmental temperature changes, a physics-informed neural network model is constructed by combining the two-sphere model with the neural ordinary differential equation model. Finally, the effectiveness of the modeling method is verified through numerical simulation and empirical data.

Changes in Otitis Media During COVID-19.

During the COVID-19 pandemic, various non-pharmaceutical interventions such as individual hygiene practices like hand washing, social distancing, and mandates for the use of masks in public spaces were implemented to reduce the spread of the disease. Otitis media (OM) is a common infectious disease. How the changed environment due to the COVID-19 pandemic has influenced the prevalence of infectious diseases like OM is not known. This study aimed to investigate how OM prevalence and trends changed during COVID-19 in Korea. OM patient data from 2017 to 2021 were extracted from the Health Insurance Review and Assessment Service database. Patients diagnosed with disease code H66 (suppurative and unspecified otitis media) were selected for analysis. Data on OM prevalence, gender, region, medical institution, and number of ventilating-tube prescriptions were analyzed. All age groups were included, and ages were categorized into 5-year ranges. The number of patients diagnosed with the OM disease code decreased continuously from 2017 to 2021 (1 598 205, 1 560 178, 1 520 948, 983 701, and 734 901). The average OM prevalence per 1000 persons decreased by 45.0% from 30.2 in 2017 to 2019 to 16.6 in 2020 to 2021. The change of OM prevalence was greater for the 0 to 5 age group than other age groups. The decrease in average prevalence per 1000 persons was greatest in the 0 to 5 age group (48.6% decrease from 358.2 in 2017-2019 to 184.1 in 2020-2021). The impact of environmental changes on ventilation-tube insertion was smaller than on OM prevalence. The average number of ventilating-tube insertions decreased by 28.1% from 27 311 in 2017 to 2019 to 19 650 in 2020 to 2021. OM prevalence decreased by 45.0%, and the number of ventilating-tube insertions decreased by 28.1% in Korea during COVID-19.

Effects of multiple future environmental changes on flooding in coastal area: Case study in Qianshan River Basin, South China

Due to their unique geographical characteristics, coastal areas are not only impacted by climate change and urbanization but also by sea level rise-induced lower boundary jacking. This makes them vulnerable to rapid, intense, and short-duration flooding events. In this study, a comprehensive analysis was conducted considering future climate change, land use change, and sea level change. By employing a hydrological model, potential flood scenarios in Qianshan River Basin were simulated in efforts to understand the combined impact of multiple environmental changes on coastal flooding. The results indicate that the flood characteristics of Qianshan River Basin will increase due to multiple future environmental changes. Notably, Dachong experiences the most significant surge in peak discharge, while Hongwanchong and Guangchangchong experience the highest increase in peak water depth under normal and extreme conditions, respectively. The inundation area’s location remains predominantly situated in the southern part of the basin, with high-risk zones substantially increasing, particularly in Tanzhou Town and the outlet of Qianshanshuidao. The observed pattern of increasing flood characteristics follows a clear trend across future scenarios SSP126, SSP245, SPP370, and SSP585. The flood characteristics resulting from a design rainfall of grade n correspond to those produced by a design rainfall of grade (n + 1), (n + 2), (n + 3), and (n + 4) in the current period, respectively.

Human and animal health in Europe: the view from the European Academies Science Advisory Council (EASAC) on challenges in infectious disease

For the last seven years, the European Academies Science Advisory Council (EASAC) has conducted a series of projects defining and clarifying priorities for European policy in infectious disease. Both human and animal populations are increasingly threatened by emerging and re-emerging infections, including zoonoses, partly attributable to the impact of environmental change on the distributions of pathogens, hosts and vectors. Among the key challenges to be faced are the impact of climate change, the increase of antibiotic resistance and the need to develop novel global surveillance and early warning systems worldwide. Multidisciplinary approaches are required to build the new interfaces between human and animal medicine (One Health), with new connections between epidemiological and environmental data for surveillance, communication and risk assessment. This multidisciplinarity involves integration between microbiology, immunology, genetics and genomics, entomology, ecology and the social sciences, among other disciplines. Improved understanding of patterns of both human and animal disease also requires commitment to standardisation of surveillance methodologies and better analysis, co-ordination and use of the data collected. There must be sustained support for fundamental research, for example to explore how pathogens cross the species barrier, encouragement for industry innovation in developing diagnostics, therapeutics and vaccines, and the increased use of scientific evidence to inform coherent strategic development across different policy-making functions and to support international leadership. Our paper is intended as an introduction to some of the issues for building collaboration between human and animal medicine, to be discussed in greater detail in the other contributions to this Issue....

Intraspecific trait variation modulates the temperature effect on elemental quotas and stoichiometry in marine Synechococcus.

Diverse phytoplankton modulate the coupling between the ocean carbon and nutrient cycles through life-history traits such as cell size, elemental quotas, and ratios. Biodiversity is mostly considered at broad functional levels, but major phytoplankton lineages are themselves highly diverse. As an example, Synechococcus is found in nearly all ocean regions, and we demonstrate contains extensive intraspecific variation. Here, we grew four closely related Synechococcus isolates in serially transferred cultures across a range of temperatures (16-25°C) to quantify for the relative role of intraspecific trait variation vs. environmental change. We report differences in cell size (p<0.01) as a function of strain and clade (p<0.01). The carbon (QC), nitrogen (QN), and phosphorus (QP) cell quotas all increased with cell size. Furthermore, cell size has an inverse relationship to growth rate. Within our experimental design, temperature alone had a weak physiological effect on cell quota and elemental ratios. Instead, we find systemic intraspecific variance of C:N:P, with cell size and N:P having an inverse relationship. Our results suggest a key role for intraspecific life history traits in determining elemental quotas and stoichiometry. Thus, the extensive biodiversity harbored within many lineages may modulate the impact of environmental change on ocean biogeochemical cycles.

Climate change may improve the habitat suitability and connectivity of sika deer (Cervus nippon) in the Shennongjia area of China

In order to effectively conserve a species and manage its population, it is critical to understand the impact of climate change on habitat quality and connectivity. The sika deer (Cervus nippon) is a ungulate species endemic to East Asia and listed as a Category I State Key Protected Wild Animals under Chinese law. The C. nippon population was established in the Shennongjia area 30 years ago, and there is an urgent need to analyse the impact of environmental change on habitat quality. In this study, we compared suitable habitats and habitat connectivity of C. nippon in the Shennongjia area by utilizing an ecological niche model that integrated a set of environmental factors combined with a cost-distance approach for both the present time as well as in the future. The most encouraging findings were that the suitable habitat for C. nippon may be obviously enlarged and its habitat connectivity obviously improved under climate change. The suitable habitat of C. nippon in the Shennongjia area is limited at present; however, it is possible that the total area and number of suitable habitat patches can increase twenty- to thirty-fold and quadruple to sextuple, respectively, in the future (2050–2070). We detected a clear trend of suitable future habitat expansion into the northeast. The number of interpatch least-cost paths may dramatically increase (up to six to twelve times higher), and the lengths of least-cost paths and movement costs for the deer may decrease by half. Based on these results, several conservation recommendations have been suggested. Our study provides a valuable reference for protective actions that can be taken to conserve C. nippon in the Shennongjia area and can serve as a template for establishing conservation strategies for other species.