Natural Laboratory Research Articles

A hairy giant among dwarves: Trichopelma grande, a distinct new species of tarantula from Cuba (Araneae: Theraphosidae)

ABSTRACT Large size, tropical climate, topographic complexity, and millions of years of isolation have turned the Greater Antillean islands into natural laboratories of evolution. Several groups have experienced explosive diversification across these islands, leading to highly diverse and endemic biotas and species experiencing unique adaptations. Here we describe a new tarantula species from the Viñales area, a biodiversity hotspot in western Cuba. Despite being a middle-sized species with large projected setae on the legs, reminiscent of those in arboreal tarantulas, phylogenomic analysis, diagnostic morphological features, and trap-door retreat building behaviour identifies it as the largest known representative of Trichopelma, and the only one with such hirsute legs. We provide mitochondrial barcoding data and a database of ultraconserved elements loci of the holotype of this species, which will help to include it in future phylogenetic studies of Theraphosidae. Given its limited distribution range, and its apparent absence in natural history collections despite its distinct appearance, this species might be scarce, positioning it as a potential conservation concern. http://www.zoobank.org/urn:lsid:zoobank.org:pub:2F9ED7A1-1345-4295-A876-6B617ABF7C75

Late Quaternary fluvial terrace characteristics and ages of the Pamir‒Tian Shan convergence zone: indications of regional climate change and tectonic uplift

The Pamir‒Tian Shan collision zone, located at the northwestern edge of the Himalaya‒Qingzang orogenic belt, provides a natural laboratory for investigating the development of fluvial terraces controlled by regional climate change and tectonic uplift. In this study, we conducted geomorphological mapping and terrestrial cosmogenic nuclide 10Be dating of fluvial terraces in the Wuheshalu syncline, within the Pamir‒Tian Shan collision zone. Four major fluvial terraces were identified in the Wuheshalu syncline, with ages of approximately 187, 141, 90, and 19 ka, respectively. These terraces were abandoned during three glacial‒interglacial transition periods (Marine Isotope Stage 6/5 (MIS6/5), cold-to-warm transition period of MIS5, and end of MIS2 or MIS2/1) and one interglacial‒glacial period (MIS7/6), and exhibit a strong correlation with regional climate change. Tectonic uplift contributed only one-third of the observed fluvial incision. These results suggest that river incision and terrace formation in the Pamir‒Tian Shan collision zone are primarily driven by periodic fluctuations in climate, with a lesser contribution from tectonic uplift.

Secondary contact erodes Pleistocene diversification in a wide-ranging freshwater mussel (Quadrula).

The isolated river drainages of eastern North America serve as a natural laboratory to investigate the roles of allopatry and secondary contact in the evolutionary trajectories of recently diverged lineages. Drainage divides facilitate allopatric speciation, but due to their sensitivity to climatic and geomorphological changes, neighboring rivers frequently coalesce, creating recurrent opportunities of isolation and contact throughout the history of aquatic lineages. The freshwater mussel Quadrula quadrula is widely distributed across isolated rivers of eastern North America and possesses high phenotypic and molecular variation across its range. We integrate sequence data from three genomes, including female- and male-inherited mitochondrial markers and thousands of nuclear encoded SNPs with morphology and geography to illuminate the group's divergence history. Across contemporary isolated rivers, we found continuums of molecular and morphological variation, following a pattern of isolation by distance. In contact zones, hybridization was frequent with no apparent fitness consequences, as advanced hybrids were common. Accordingly, we recognize Q. quadrula as a single cohesive species with subspecific variation (Q. quadrula rumphiana). Demographic modeling and divergence dating supported a divergence history characterized by allopatric vicariance followed by secondary contact, likely driven by river rearrangements and Pleistocene glacial cycles. Despite clinal range-wide variation and hybridization in contact zones, the process-based species delimitation tool delimitR, which considers demographic scenarios like secondary contact, supported the delimitation of the maximum number of species tested. As such, when interpreting species delimitation results, we suggest careful consideration of spatial sampling and subsequent geographic patterns of biological variation, particularly for wide-ranging taxa.

The Middle East as a Natural Laboratory to Advance Our Understanding of Global Hyper-Arid Drylands

The Middle East as a Natural Laboratory to Advance Our Understanding of Global Hyper-Arid Drylands

Influence of Overpressured Fluid Expulsion on Hydrocarbon Accumulation in Deep‐Buried Miocene Reservoirs of the Yinggehai Basin, Northwestern South China Sea

ABSTRACTThe overpressure record of the Cenozoic rifting basins in China was recently renewed in the Miocene reservoirs of the Yinggehai Basin, which became an ideal natural laboratory for revealing the hydrocarbon accumulation mechanism under the ultrahigh overpressure setting. Using 3D seismic data, two new fluid expulsion structures were identified in the Yinggehai Basin: layer‐bound faults and pipes. Layer‐bound faults were primarily generated at ~10.5 Ma and subsequently served as vertical channels for hydrocarbon migration. Pipes can be divided into three episodes, generated at ~5.5, ~2.4 and < 1.9 Ma, caused by hydraulic fracturing during focused flow in highly overpressured reservoirs. Pipes generated simultaneously with hydrocarbon charging indicate that the aqueous pressure before hydrocarbon charging did not reach the threshold of hydraulic fracturing and could result in dynamic hydrocarbon accumulation. In contrast, pipes generated before and after hydrocarbon charging increased the unfilling and draining risks of the traps, respectively.

Non-Random Distribution of Boreus hyemalis Among Bryophyte Hosts: Evidence from Field and Laboratory Tests

Our understanding of herbivorous insect’s host selection is often based on observed associations with host plants, which can be biased by relative plant abundance, leading to inaccurate assumptions of preference. These biases may be particularly pronounced for insects associated with bryophytes, where dominance patterns are less evident. Estimating selection tendencies is also challenging for rare species with unique ecologies. Boreus hyemalis, a winter-active insect, associates with a range of bryophyte species, yet its specificity in moss-host selection remains unclear. This study investigates whether B. hyemalis shows non-random distribution among bryophyte species in natural habitats and laboratory settings. Field surveys revealed associations with 21 moss species, with significant selection tendencies toward Dicranella heteromalla and Hypnum cupressiforme, with moss species richness being a key factor for boreid inhabitance. Laboratory tests assessed selection among 14 moss species, including H. cupressiforme morphotypes, under controlled conditions. Results indicated Polytrichum formosum was the most frequently selected in the lab. Despite some discrepancies between field and lab findings, B. hyemalis shows specific selection tendencies for particular moss species. These results provide new insights into the ecological interactions between bryophytes and this winter-active insect, emphasizing the importance of moss structure and species richness in shaping B. hyemalis distribution.

Thermodynamics of the Primordial Universe

This review delves into the pivotal primordial stage of the universe, a period that holds the key to understanding its current state. To fully grasp this epoch, it is essential to consider three fundamental domains of physics: gravity, particle physics, and thermodynamics. The thermal history of the universe recreates the extreme high-energy conditions that are critical for exploring the unification of the fundamental forces, making it a natural laboratory for high-energy physics. This thermal history also offers valuable insights into how the laws of thermodynamics have governed the evolution of the universe’s constituents, shaping them into the forms we observe today. Focusing on the Standard Cosmological Model (SCM) and the Standard Model of Particles (SM), this paper provides an in-depth analysis of thermodynamics in the primordial universe. The structure of the study includes an introduction to the SCM and its strong ties to thermodynamic principles. It then explores equilibrium thermodynamics in the context of the expanding universe, followed by a detailed analysis of out-of-equilibrium phenomena that were pivotal in shaping key events during the early stages of the universe’s evolution.

Observed Variability in Convective Cell Characteristics and Near-Storm Environments across the Sea- and Bay-Breeze Fronts in Southeast Texas

Abstract During the DOE Atmospheric Radiation Measurement (ARM) Tracking Aerosol Convection Interactions Experiment (TRACER) IOP spanning June–September 2022, two fixed ARM sites and a mobile team concurrently sampled the airmass heterogeneity across sea- and bay-breeze fronts around the greater Houston metropolitan region. Here, we quantify the spatiotemporal variability between maritime (coastal/bay side of breeze fronts) and continental (inland side of breeze fronts) air masses over 15 IOP days characterized by strong sea-breeze forcing. We analyze environmental profile data from 177 radiosondes and use S- and C-band radar data to track and quantify the variability in attributes of more than 2300 shallow and transitioning cells across different air masses. The composite analysis of environmental profiles indicates that during the early afternoon, the sea-breeze maritime air mass exhibits lower convective available potential energy (CAPE) than the bay-breeze maritime air mass. As the sea breeze advances inland with time, CAPE within the maritime air mass exceeds that of the continental air mass to the north of the breeze fronts. In general, maritime cells have a larger mean composite reflectivity and cell widths than continental cells; however, the response varies between shallow and transitioning cells. Mean composite 20-dBZ echo-top heights, however, are similar across air masses for both shallow and transitioning cells. The continental and maritime inflow air mass for transitioning cells has significantly different mean values for mixed-layer entrainment CAPE, lifted condensation level, level of free condensation, boundary layer depth, and diluted equilibrium level. For shallow cells, only total precipitable water shows a significant difference. Significance Statement The greater Houston metropolitan area is a natural laboratory for understanding the individual impacts of background meteorology and aerosols on convective clouds. Due to its proximity to the Gulf Coast and Galveston Bay, the Houston region experiences a diurnal precipitation cycle in the summer, driven by convection triggered from sea- and bay-breeze fronts. These fronts act as a boundary between air masses with distinct thermodynamic and environmental characteristics. Convergence along these fronts and interactions between storm outflow and the fronts facilitate convection initiation in different mesoscale air masses. This study quantifies the heterogeneity among these air masses while investigating their influence on cloud microphysics. We find that the effect of airmass heterogeneity is more pronounced for the bulk microphysical properties in shallow clouds.

Beyond genes‐for‐behaviour: The potential for genomics to resolve long‐standing questions in avian brood parasitism

AbstractBehavioural ecology by definition of its founding ‘Tinbergian framework’ is an integrative field, however, it lags behind in incorporating genomic methods. ‘Finding the gene/s for a behaviour’ is still rarely feasible or cost‐effective in the wild but as we show here, genomic data can be used to address broader questions. Here we use avian brood parasitism, a model system in behavioural ecology as a case study to highlight how behavioural ecologists could use the full potential of state‐of‐the‐art genomic tools. Brood parasite–host interactions are one of the most easily observable and amenable natural laboratories of antagonistic coevolution, and as such have intrigued evolutionary biologists for decades. Using worked examples, we demonstrate how genomic data can be used to study the causes and mechanisms of (co)evolutionary adaptation and answer three key questions for the field: (i) Where and when should brood parasitism evolve?, (ii) When and how should hosts defend?, and (iii) Will coevolution persist with ecological change? In doing so, we discuss how behavioural and molecular ecologists can collaborate to integrate Tinbergen's questions and achieve the coherent science that he promoted to solve the mysteries of nature.

Neogene shale-detached extension and contraction linked system in the Akal Fold and Thrust Belt, Southeast Mexico

Structures related to shale mobility represent an important challenge for proper interpretation in seismic data sets. The large number of seismic sections obtained in recent times of the Akal Fold and Thrust Belt (AFTB) makes this province a natural laboratory for studying shale-related structural styles. The interpretation of two orthogonal 2D seismic sections reveals the geometry of a gravity-driven extension-contraction structural system that developed in the central portion of the AFTB during the Late Miocene to the Early Pliocene. The gravity-driven system was triggered by increasing the sedimentary load in the Miocene and developed a set of listric faults and related growth strata. The contracting structures are the in-sequence fold thrust that evolved from shale-cored detachment anticlines. An Oligocene sequence of soft, weak shale with alternating, rigid layers of sandstone and limestone and a low-resistivity signature acts as the detachment of the gravity-driven system. The progressive sequential restoration of a structural cross section provides more information about the progression of the gravity-driven system. We suggest that mobility started when the Oligocene shale reached a critical condition at >2–3 km burial depth. The coeval northeastward regional Chiapanecan shortening interferes with the last stage of the shale detachment (the Early Pliocene) in the study area and masks the previous interpretation of the gravity-driven system.

Controls on Corundum Formation: Metasomatism of Ultramafic Rock, Nattavit, South-East Greenland

Abstract The geotectonic setting for plumasite-type corundum occurrences is understudied, even though it is of importance for the understanding of trace-element patterns used for fingerprinting of ruby and sapphire. Mineral reactions related to metasomatism caused by pegmatite intrusion into ultramafic rock result in a characteristic trace element signature in corundum and thereby control its colour. The Nattivit area, Isertoq Terrane, South-East Greenland, provides a natural laboratory to investigate these mineral reactions and corundum trace element patterns given the excellent exposure of a typical plumasite-type occurrence where pegmatites intruded ultramafic rocks of different composition, namely lherzolite and dunite. The pegmatite dykes are 10 to 50 cm wide in the ultramafic rocks, whereas the adjacent alteration zone in the ultramafic rock reaches widths between 10 and 30 cm. Metasomatism resulted in desilication of the pegmatites and a decrease in Ca, Mg, K, Mn, Al and Fe away from the centre of the pegmatite dyke. Chromium, Ni, Mg, Fe, Sc, Co, V, Zn, Ti and Mn in the metasomatic reaction zones are predominantly derived from the ultramafic rock. We identify three zones with different mineral assemblages. In the lherzolite, tschermakite and biotite are formed in the centre of the reaction zone, which is followed by anorthite-rich plagioclase, hercynite, dolomite and ultimately pink corundum that occurs in the most heavily reacted part of the metasomatic reaction zone. The metasomatic reaction zones in the ultramafic rock include an intense reactionzone at direct contact to the pegmatite dyke with biotite and actinolite, and two alteration zones further away from the pegmatite dyke with enstatite, actinolite, anthophyllite, phlogopite, dolomite, sulphide, apatite and chrome-spinel. In the dunite, no biotite formed and hence, corundum contains more Fe, Mg and Ti. The plumasite-type corundum from Nattivit contains more Fe than Cr, which is typical of pink corundum hosted in mafic-ultramafic rocks. The corundum-forming reaction is dated from the pegmatite vein to 1843±4 Ma (U-Pb zircon age), which is coinciding with convergence of the Rae and North Atlantic cratons resulting in the Nagssugtoqidian Orogen. Only syn-tectonic, corundum-normative, peraluminous, calc-alkaline pegmatites of granitic to granodioritic composition that intrude into ultramafic rocks in the upper plate formed corundum in this area. The pegmatites are classified as muscovite class granitic pegmatites and intruded at upper amphibolite facies conditions. These pegmatites possible originated from partial melting of mafic granulite or a subducted oceanic plate. The formation of granitic pegmatites and related corundum mineralization in the upper plate of a collisional orogen described here is comparable to other corundum occurrences, e.g. Polar Urals, and thus is regarded as a typical geotectonic setting for plumasite-type corundum.

Higher oxygen content and transport characterize high-altitude ethnic Tibetan women with the highest lifetime reproductive success

We chose the "natural laboratory" provided by high-altitude native ethnic Tibetan women who had completed childbearing to examine the hypothesis that multiple oxygen delivery traits were associated with lifetime reproductive success and had genomic associations. Four hundred seventeen (417) women aged 46 to 86 y residing at ≥3,500 m in Upper Mustang, Nepal, provided information on reproductive histories, sociocultural factors, physiological measurements, and DNA samples for this observational cohort study. Simultaneously assessing multiple traits identified combinations associated with lifetime reproductive success measured as the number of livebirths. Women with the most livebirths had distinctive hematological and cardiovascular traits. A hemoglobin concentration near the sample mode and a high percent of oxygen saturation of hemoglobin raised arterial oxygen concentration without risking elevated blood viscosity. We propose ongoing stabilizing selection on hemoglobin concentration because extreme values predicted fewer livebirths and directional selection favoring higher oxygen saturation because higher values had more predicted livebirths. EPAS1, an oxygen homeostasis locus with strong signals of positive natural selection and a high frequency of variants occurring only among populations indigenous to the Tibetan Plateau, associated with hemoglobin concentration. High blood flow into the lungs, wide left ventricles, and low hypoxic heart rate responses aided effective convective oxygen transport to tissues. Women with physiologies closer to unstressed, low altitude values had the highest lifetime reproductive success. This example of ethnic Tibetan women residing at high altitudes in Nepal links reproductive fitness with trait combinations increasing oxygen delivery under severe hypoxic stress and demonstrates ongoing natural selection.

Adria microplate: a puzzling key stone in west-central Mediterranean geodynamics

The Mediterranean region denotes a special plate tectonic environment as the two big plates, Africa and Eurasia, primarily provide the main frame while the dominant players are the small oceanic basins and the continental micro plates (MP) that for the past 80 Ma was the Adria MP. In this environment slab rollback subduction, orogenic arc formation and rotation of crustal blocks are common. While the tectonic setting and involvement in geodynamic processes of Adria MP might not be unique in global terms, it presents Adria as an ideal natural laboratory to study the geodynamic processes individually and in their combined effects in a generally well-studied and rather wellaccessible region. The current extension of the Adria MP is defined by the continental Moho as far into the bounding orogens as the latter could be confirmed. The slabs surrounding Adria dominate and characterize the geodynamics of this MP and in most cases their geometries and the possible connection with Adria are well defined by tomographic images. The Ionian oceanic lithosphere slab subducting beneath Calabria has been torn off and detached from the very short South Apennines slab remaining attached to Adria. On the southeastern side we observe the Adria slab beneath the Hellenides that seems detached from the Ionian oceanic lithosphere slab of the Hellenic subduction zone. Along the Dinarides a slab gap is observed analogue to the slab window on Adria MP’s western side between the South Apennines and the North Apennines. Encircled by three orogens, the Adria continental lithosphere has been and still is strongly affected by the subductions surrounding it. In the northern part of the Adria MP, the North Apennines slab rollback is the obvious dominant geodynamic force acting locally on the plate while in contrast, the slabs beneath the Eastern Alps and beneath the Hellenides seem stagnant. This study presents a brief overview of the wealth of information aiming to summarize the main constraints on Adria MP available and it discusses some of the questions surrounding this key player in west-central Mediterranean geodynamics.

Microbiome flexibility enhances the resilience of the potentially invasive coral Tubastraea aurea to abrupt environmental changes: Insights from a shallow water hydrothermal vent transplantation study

To comprehend the effects of potentially invasive coral Tubastraea aurea on marine ecosystems, it is crucial to understand their adaptive strategies to survive environmental changes and perturbations. Therefore, a cross-transplantation study was conducted to assess the microbiome's role in the resilience of T. aurea to sudden environmental changes.Hydrographic analyses revealed distinct ecological conditions at two sites: a hydrothermal vent (HV) site, characterized by harsh environmental conditions serving as a natural laboratory for future oceanic changes, and a regular coastal site Fulong (FU). Both sites showed significant differences in pH, temperature, and dissolved oxygen. Using Oxford Nanopore Technologies, we examined bacterial dynamics in coral tissue, mucus and ambient sediment samples following cross-transplantation experiments. We observed a rapid shift in dominant bacterial groups post-transplantation with transplanted corals acquiring microbiomes similar to native corals from their respective sites within 16 days. The bacteria Endozoicomonas euniceicola and Ruegeria profundi were dominant in both native and transplanted corals, suggesting their critical role in coral resilience. Furthermore, the enrichment of certain bacterial taxa post-transplantation suggests that opportunistic species also contribute to host acclimatization. Functional profiling data indicated that there was site-specific adaptation because corals had acquired beneficial bacterial assemblages to assist them cope with environmental stressors. More specifically, there was a switch towards sulfur and nitrogen metabolism in corals that moved to high sulfidic environments, while corals transplanted into normal coastal environments showed enriched photoautotrophic processes due to their symbionts. Our study underscored the highly flexible microbiome of T. aurea and its pivotal role in facilitating host resilience to environmental perturbations, particularly in the context of its potential invasiveness. Hence, these findings contribute to the understanding of coral-microbiome dynamics and emphasize the necessity of considering microbially-mediated resilience in managing potentially invasive coral species in marine ecosystems around the world, especially as ocean conditions continue to change.

The Role of Hydrocarbons in the Genesis of Mississippi-Valley-Type (MVT) Zn–Pb Deposits: Insights from In Situ Sulfur Isotopes of Sphalerite from the Southwestern Margin of the Yangtze Block, SW China

The coexistence of numerous Mississippi-Valley-type (MVT) Zn–Pb deposits and (paleo) oil/gas reservoirs in the world suggests a close genetic relationship between mineralization and hydrocarbon accumulation. Xuequ–Shandouya middle MVT Zn–Pb deposits are mainly hosted in the Lower Cambrian Maidiping Member siliceous dolostone on the southwestern margin of the Yangtze Block, accompanied by large amount of bitumen in the orebodies. Therefore, this type of Zn–Pb deposit is a natural laboratory for studying the relationship between the mineralization and the accumulation of paleo-oil/gas reservoirs. The deposit is characterized by spheroidal and concentric banded sphalerite. In situ sulfur isotope studies are carried out to determine the sulfur sources, sulfate reduction mechanisms, and role of hydrocarbons in the zinc–lead mineralization process. According to the mineral paragenesis and relative temporal relationship, two mineralization stages (1 and 2) are identified. An in situ sulfur isotope analysis of spheroidal and concentric banded sphalerite particles from Stage 2 shows that there are the two following types of sulfur isotopes in the sphalerite: one with relatively invariable δ34S values in the core (+8.31 to +9.30‰), and the other with a gradual increase from the core margin (core) to the rim (+0.39 to +16.18‰). These two types reflect that they may have formed in different times, with first type forming in the early period of Stage 2, while the second type was formed in the late period of Stage 2. The sulfur isotopic data suggest the sulfur source of evaporated sulfate minerals and multiple formation mechanisms for reduced sulfur (H2S). In the early period of Stage 2 mineralization, the sulfate reduction mechanism is mainly a mixture of bacterial sulfate reduction (BSR) and/or thermochemical sulfate reduction (TSR), while a very small amount may come from the thermal decomposition of organic compounds (DOCs). In the late period of Stage 2, TSR is dominant, and the gradual increase in the δ34S value may be related to Rayleigh fractionation. The oil/gasreservoir not only acts as a reducing agent to provide the required hydrogen sulfide for zinc–lead mineralization through TSR or BSR, but also provides reduced sulfur for mineralization through the thermal decomposition of organic compounds directly.

Optimizing Science Laboratory Management for Enhanced Student Learning Outcomes

Background: Laboratory management is vital for improving science education, yet many institutions struggle to optimize these resources. Specific Background: Effective management enhances student interest and practical skills in natural sciences, but inadequate management leads to underutilization of laboratory facilities, negatively impacting learning experiences. Knowledge Gap: While the importance of laboratory management is acknowledged, studies on specific practices and their effects on student engagement in natural science remain limited. Aims: This study explores management practices in a natural science laboratory and their implications for educational outcomes. Results: Findings reveal that planning, organization, implementation, supervision, and evaluation are poorly executed, resulting in incomplete documentation and minimal follow-up. Although practical activities spark student interest, systemic issues hinder their effectiveness. Novelty: The research provides new insights into the operational challenges of laboratory management in a specific educational context. Implications: Enhanced management strategies are necessary to improve resource allocation and laboratory utilization, fostering student engagement and skill development in natural sciences. Highlights : Critical Role: Effective laboratory management enhances student interest and practical skills in science education. Systemic Issues: Inadequate management practices lead to underutilization of laboratory resources, negatively impacting learning experiences. Need for Improvement: Enhanced strategies are essential for optimizing resource allocation and fostering student engagement in natural sciences. Keywords: laboratory management, science education, student engagement, practical skills, educational outcomes

Does Proportionality Increase Turnout? A Study of Adaptation to Oscillating Electoral Systems

Does proportionality increase turnout? This article studies a national electoral reform in early twentieth-century Argentina that was implemented asymmetrically across districts, creating a natural laboratory in which some districts oscillated between electoral systems across elections. Leveraging this unusual variation in a difference-in-differences design, this article shows that a shift from multi-member plurality rules towards a slightly more proportional system—which removed one-third of the contested seats from the grasp of the dominant party—led to a four percentage point increase in turnout. An investigation into causal mechanisms indicates that more proportional rules, by increasing the odds that smaller parties obtain seats, promoted strategic party entry and intensified electoral competition, both between and within parties. These findings complement existing quasi-experimental results that focus exclusively on elections in European democracies, confirm that parties are able to adapt immediately to changes in electoral rules, and refute the belief that proportionality does not affect turnout in Latin America.

Separation of the Urbanization Effects on Thermal Environment

Rapid urbanization leads to changes in the thermal characteristics of urban areas. Despite cities serving as natural laboratories to investigate responses to global change, it remains unclear how urbanization affects the thermal environment during global warming. Urbanization effects can be categorized as either the effect of urban climate (UCE) or land cover change (LCCE). This study proposes a conceptual framework for separating the urbanization effects on the thermal environment in 29 major Chinese cities. Results show that land surface temperature increases with impervious surface fractions in the urban area and decreases with vegetation fractions in rural areas, resulting in significant UCE and LCCE across cities, with LCCE approximately 1.3 to 5.7 times greater than UCE. These findings provide a comprehensive understanding of the thermal environment change caused by urbanization. To mitigate the negative effects of urbanization on the thermal environment, reducing land cover change would be more effective.

The quantum yield of O(1S) in CO2 photolysis retrieved from the Martian atmosphere

Photochemistry studies the interactions between light and molecules. Ultraviolet radiation interacts with the atmosphere, and due to its energy, it can dissociate, excite, or ionize its constituents, which initiate other processes. A good knowledge of the interaction between photons of different energies with molecules and atoms is crucial for accurately modeling the atmospheric physics and for climate predictions. Despite its importance, photo-fragment dynamics lacks data because the experimental setup is difficult. We used the upper Martian atmosphere as a natural laboratory to measure the quantum yield O(1S) from CO2 + hv as a function of wavelength. We analyzed 4 years of continuous remote-sensing observations from the NASA MAVEN/IUVS spectrograph within a Bayesian framework analysis tool. We retrieved the quantum yield for the first time through its entire production spectral range, ≈80–126 nm, and achieved uncertainty from 10% to 20% on average. While at Lyman-α (121.6 nm), we achieved a precision of 2% by taking advantage of the properties of the upper Martian atmosphere.

Bacterial community and antibiotic resistance genes assembly processes were shaped by different mechanisms in the deep-sea basins of the Western Pacific Ocean.

As the intrinsic property of microorganisms, antibiotic resistance genes (ARGs) are fundamentally coupled to microbially-linked biogeochemical processes within ecosystems. However, human activities often obscure the natural distribution of ARGs through deterministic selective pressures. The deep-sea basin of the western Pacific Ocean is one of the least disturbed areas globally by human activities, providing a natural laboratory to investigate the intrinsic mechanisms governing ARGs in natural environments. In this study, we analyzed bacterial community and ARG diversity in 15 surface sediment samples from three deep-sea basins in the western Pacific Ocean. The relative abundance of ARGs in the surface sediments ranged from 3.10 × 10-3 to 5.37 × 10-2 copies/16S rRNA copies, with multidrug and β-lactam resistance genes dominated in all samples (49.06%-100%). The bacteria were mainly dominated by the Proteobacteria. The principal coordinate analysis (PCoA) showed significant spatial heterogeneity of ARGs and bacteria among the three basins. Null model, neutral community models (NCM), and normalized stochasticity ratio (NST) indicated that bacterial community was dominated by stochastic assembly, driven by geographic barriers leading to independent evolution. Conversely, the NST revealed that the ARGs profile was mainly shaped by deterministic processes. Environmental factors are more crucial than geographical factors and bacterial community for ARG occurrence among the selected factors. Meanwhile, we found that the spread of ARGs was mainly through vertical gene transfer in the pre-antibiotic era. The disparity between the assembly processes of bacterial community and ARGs may be attributed to the fact that ARG hosts were not the dominant bacteria in the community. This study first reported the distribution and assembly processes of ARGs and bacterial community in surface sediments of the western Pacific.