Hasil untuk "Natural history (General)"

F. Lomoc, N. Canosa, A. P. Boette et al.

We present a method for analyzing general time series by employing the history state formalism of quantum mechanics. This formalism allows us to describe a complete evolution based on a single quantum state, the history state, which simultaneously includes -also as a quantum system- the reference clock. It naturally leads to the concept of system-time entanglement, with the ensuing entanglement entropy constituting a measure of the effective number of distinguishable states visited in the history. Through a quantum coherent state embedding of the time series data, it is then possible to associate a quantum history state to the series. The gaussian overlap between these coherent states provides thus a smooth measure of distinguishability between the series data. The eigenvalues of the corresponding overlap matrix determine in fact the entanglement spectrum and entropy of the history state, which provide a rigorous characterization of the evolution. As illustration, the formalism is applied to typical financial time-series data. Through the entanglement entropy and spectrum, different evolution regimes can be identified. Entanglement based volatility indicators are also derived, and compared with standard volatility measures.

Hao Wang, Jinnan Jiang, Muhammad Ali et al.

Plumes and pockmarks are formed when shallow gas breaches the seabed and infiltrates into ocean currents, disrupting the original ecological environment and affecting biological habitats and migration behaviors. An independently developed experimental system was employed in this study to investigate the effects of gas source pressure, burial depth, and number of release orifices on plume morphology and pockmark characteristics, aiming to evaluate their impacts on seabed ecological functions. Experimental results show that the maximum fountain height and plume diameter increase no-linearly with the increase in pressure and orifice number but decrease with increasing burial depth. The plume angle is positively correlated with pressure and negatively correlated with burial depth, showing no correlation with orifice number. Pockmark depth, diameter, and volume exhibit similar variation trends, with pressure being the dominant factor. Analysis of variance reveals that pockmark volume is most sensitive to pressure, while diameter has the least influence. Soil strength measurements after gas release demonstrate distinct patterns: strength increases in the pockmark center and external areas due to compaction, whereas it decreases in the waistline and edge regions due to shear failure. These changes may regulate benthic community distribution by altering sediment stability and pore water chemistry. The findings provide experimental insights into how gas release parameters influence submarine geomorphology and sedimentary environments, contributing to risk assessment of marine ecological disturbances associated with shallow gas activities.

Elena D. Concepción

The EU institutions must align their visions for the future and decide if the EU will lead the transformative systemic change required to achieve the United Nations’ goals on climate, biodiversity, and sustainable development. If so, the EU must move beyond hesitation and inconsistency and commit to integrate coherent concrete actions across all sectoral policies and regulations to truly drive a genuine transformative change that ensures a thriving future for all.

Ping Li, Ping Li, Zhaoli Zhou et al.

Hainan gibbon (Nomascus hainanus) is China’s only endemic gibbon species and among the world’s rarest primate species. Documenting infant mortality and investigating their underlying causes are essential for informing evidence-based conservation strategies to support population recovery. From 2010 to 2024, we conducted demographic monitoring and behavioral observations of extant gibbon groups in Bawangling area of Hainan Tropical Rainforest National Park, China, recording four infant mortality cases through ad libitum sampling. Among these, three infants (75%) were born to primiparous females, while one (25%) was born to a multiparous female. Notably, we documented for the first time that 4-month-old infants began to move away from their mothers, and infant mortality events coincided temporally with their initial attempts at independent activities. These findings suggest that inadequate parenting experience (primiparity) in females and premature infant independence would be critical determinants of neonatal survival in Hainan gibbons. Specifically, infants born to primiparous mothers, particularly those aged 4-6 months, face elevated risks of accidental mortality. We propose that conservation efforts prioritize enhanced patrols and rescue protocols during this high-vulnerability stage. Long-term monitoring of infant birth-death dynamics, coupled with rigorous investigation of causative factors, is imperative for the conservation and population recovery of this Critically Endangered species.

L. Filipe O. Costa, Francisco Frutos-Alfaro, José Natário et al.

In a recent paper we discussed when it is possible to define reference frames nonrotating with respect to distant inertial reference objects (extension of the IAU reference systems to exact general relativity), and how to construct them. We briefly review the construction, illustrating it with further examples, and caution against the recent misuse of zero angular momentum observers (ZAMOs).

Emiel van Miltenburg, Chenghua Lin

This article provides a brief overview of the field of Natural Language Generation. The term Natural Language Generation (NLG), in its broadest definition, refers to the study of systems that verbalize some form of information through natural language. That information could be stored in a large database or knowledge graph (in data-to-text applications), but NLG researchers may also study summarisation (text-to-text) or image captioning (image-to-text), for example. As a subfield of Natural Language Processing, NLG is closely related to other sub-disciplines such as Machine Translation (MT) and Dialog Systems. Some NLG researchers exclude MT from their definition of the field, since there is no content selection involved where the system has to determine what to say. Conversely, dialog systems do not typically fall under the header of Natural Language Generation since NLG is just one component of dialog systems (the others being Natural Language Understanding and Dialog Management). However, with the rise of Large Language Models (LLMs), different subfields of Natural Language Processing have converged on similar methodologies for the production of natural language and the evaluation of automatically generated text.

Miguel Baltazar‐Soares, J. Robert Britton, Adrian Pinder et al.

Abstract Sea lamprey Petromyzon marinus is an anadromous and semelparous fish without homing behaviors. Despite being a freshwater, free‐living organism for a large part of their life cycle, its adulthood is spent as a parasite of marine vertebrates. In their native European range, while it is well‐established that sea lampreys comprise a single nearly‐panmictic population, few studies have further explored the evolutionary history of natural populations. Here, we performed the first genome‐wide characterization of sea lamprey's genetic diversity in their European natural range. The objectives were to investigate the connectivity among river basins and explore evolutionary processes mediating dispersal during the marine phase, with the sequencing of 186 individuals from 8 locations spanning the North Eastern Atlantic coast and the North Sea with double‐digest RAD‐sequencing, obtaining a total of 30,910 bi‐allelic SNPs. Population genetic analyses reinforced the existence of a single metapopulation encompassing freshwater spawning sites within the North Eastern Atlantic and the North Sea, though the prevalence of private alleles at northern latitudes suggested some limits to the species' dispersal. Seascape genomics suggested a scenario where oxygen concentration and river runoffs impose spatially varying selection across their distribution range. Exploring associations with the abundance of potential hosts further suggested that hake and cod could also impose selective pressures, although the nature of such putative biotic interactions was unresolved. Overall, the identification of adaptive seascapes in a panmictic anadromous species could contribute to conservation practices by providing information for restoration activities to mitigate local extinctions on freshwater sites.

Fortunatus Masanja, Ke Yang, Yang Xu et al.

Heatwaves have become increasingly frequent and intense, posing a significant threat to the survival and health of marine bivalves. The temperature fluctuations associated with heatwaves can cause significant alterations in the composition and quantity of microbial communities in bivalves, resulting in changes to their immunological responses, gut microbiome, oxidative stress levels, and other physiological processes and eventually making them more susceptible to diseases and mass mortalities. This is particularly concerning because some of these bivalves are consumed raw, which could represent a risk to human health. This paper provides an overview of the current state of knowledge regarding the impact of marine heatwaves on bivalves and their microbial communities, demonstrating the intricate relationship between heatwaves, microbial ecosystems, and bivalve health. Our analysis highlights the need for additional research to establish the underlying mechanisms of these reactions and to develop appropriate conservation and management strategies to limit the impact of heatwaves on bivalves and their microbial ecosystems.

Julia D. Sigwart, Angelika Brandt, Angelika Brandt et al.

The abyssal plains are vast areas without large scale relief that occupy much of the ocean floor. Although long considered relatively featureless, they are now known to display substantial biological heterogeneity across different spatial scales. Ecological research in these regions benefits increasingly from non-destructive visual sampling of epifaunal organisms with imaging technology. We analysed images from ultra-high-definition towed camera transects at depths of around 3500 m across three stations (100–130 km apart) in the Bering Sea, to ask whether the density and distribution of visible epifauna indicated any substantial heterogeneity. We identified 71 different megafaunal taxa, of which 24 occurred at only one station. Measurements of the two most abundant faunal elements, the holothurian Elpidia minutissima and two xenophyophores morphotypes (the more common identifiable as Syringammina limosa), indicated significant differences in local densities and patchy aggregations that were strikingly dissimilar among stations. One station was dominated by xenophyophores, one was relatively depauperate in both target taxa as well as other identified megafauna, and the third station was dominated by Elpidia. This is an unexpected level of variation within comparable transects in a well-mixed oceanic basin, reinforcing the emerging view that abyssal habitats encompass biological heterogeneity at similar spatial scales to terrestrial continental realms.

Guoqin Tang, Zengan Deng, Zengan Deng et al.

Internal tides have a great impact on the meridional overturning circulation and climate variability through contributing to diapycnal mixing. The Luzon Strait (LS) is one of the most important sites of internal tide generation in the global ocean. In this study, we evaluate the effect of the Kuroshio on the M2 and K1 internal tides in both summer and winter seasons in the South China Sea (SCS), particularly within the LS. High-resolution ocean numerical simulations with the Kuroshio Current were compared with those without. We found that the Kuroshio has negligible impact on the generation site of internal tides. Compared to seasonal variability in the total barotropic to baroclinic conversion rate over the LS, the Kuroshio has relatively little influence. However, the Kuroshio flow strongly guides the propagating direction of the internal tides from the LS into the SCS. The Kuroshio also substantially decreases the southward energy fluxes going out of the LS. For both M2 and K1 tides, turning off the Kuroshio leads to a weaker energy exchange between the background shear and internal tides. Turning off the Kuroshio also weakens the divergence of internal tide energy due to the advection of background flow. Thus, our results reveal a non-negligible effect of the Kuroshio on the internal tides in the LS. If one aims to realistically simulate, or better understand, internal tides, these results indicate that one should include realistic oceanic circulation fields.

Rebeka Aszalósné Balogh, Edit Farkas, Júlia Tüdősné Budai et al.

Cryptogams, often neglected in vegetation dynamics studies, compose a large part of biomass and contribute to the biodiversity of sandy grasslands. Since the work of Verseghy (1970s), their productivity has not been analyzed in Hungary. We studied the lichen and bryophyte dynamics (hereinafter called cryptogams) at two Eastern Hungarian dry sandy grassland sites. The sites of <i>Corynephorus canescens</i> and of <i>Festuca vaginata</i> dominance, respectively, belonging to the community <i>Festuco vaginatae–Corynephoretum</i> have been monitored. We aimed at (1) quantifying the diversity and biomass of the cryptogamic communities; (2) exploring the cryptogamic response to management changes; and (3) studying the effect of experimental management (fencing) on the cryptogamic assemblages. The sites have been compared in 2013 and 2018, respectively. Forty microplots per site per management have been analyzed in both years. Samples of lichens and bryophytes were hand-sorted, dried and then measured. Fencing has led to increased biomass of cryptogams within a few years. Lichens in general benefited comparatively more from exclosure than bryophytes. The increase in lichen biomass (especially that of <i>Cladonia rangiformis</i>) is clearly due to the over 10-year absence of grazing. The only lichen favored by moderate grazing is the legally protected <i>C. magyarica</i>. Short spells of low-intensity grazing can promote the species richness of cryptogams in the community.

William J. Wolf

I apply Dawid's Meta-Empirical Assessment (MEA) methodology to the theory of cosmological inflation. I argue that applying this methodology does not currently offer a compelling case for ascribing non-empirical confirmation to cosmological inflation. In particular, I argue that despite displaying strong instances of Unexpected Explanatory Coherence (UEA), it is premature to evaluate the theory on the basis of the No Alternatives Argument (NAA). More significantly though, I argue that the theory of cosmological inflation fails to sustain a convincing Meta-Inductive Argument (MIA) because the empirical evidence and theoretical successes that it seeks to draw meta-empirical support from do not warrant a meta-inductive inference to inflation. I conclude by assessing how future developments could pave the way towards crafting a more compelling case for the non-empirical confirmation of cosmological inflation.

Hagit Kvitt, Hagit Kvitt, Assaf Malik et al.

The current decrease in oceanic dissolved oxygen is a widespread and pressing problem that raises concern as to how marine biota in general, and coral reefs in particular will be affected. However, the molecular response underlying tolerance of corals to prolonged severe deoxygenation where acclimation to hypoxia can accrue is not yet known. Here, we investigated the effect of two weeks of continuous exposure to conditions of extreme deoxygenation, not hitherto exerted under laboratory conditions (~ 0.35 mg L−1 dissolved oxygen), on the physiology and the diurnal gene expression of the coral, Stylophora pistillata. Deoxygenation had no physiologically significant effect on tissue loss, calcification rates, symbiont numbers, symbiont chlorophyll-a content and symbiont photosynthesis rate. However, deoxygenation evoked a significant transcriptional response that was much stronger at night, showing an acute early response followed by acclimation after two weeks. Acclimation included increased mitochondria DNA copy numbers, possibly increasing energy production. Gene expression indicated that the uptake of symbiosis-derived components was increased together with a decrease in nematocyst formation, suggesting that prolonged deoxygenation could enhance the corals’ need for symbiosis-derived components and reduces its predation abilities. Coral orthologs of the conserved hypoxia pathway, including oxygen sensors, hypoxia-inducible factor (HIF) and its target genes were differentially expressed in a similar temporal sequence as observed in other metazoans including other species of corals. Overall, our studies show that by utilizing highly conserved and coral–specific response mechanisms, S. pistillata can acclimate to deoxygenation and possibly survive under climate change-driven oceanic deoxygenation. On the other hand, the critical importance of algal symbionts in this acclimation suggests that any environmental perturbations that disrupt such symbiosis might negatively affect the ability of corals to withstand ocean oxygen depletion.

Fengping Li, Fengping Li, Jiawen Zheng et al.

The marine gastropod Strombidae is widely distributed in tropical and subtropical regions all over the world and possesses high morphological diversity. In order to better understand how morphological characteristics evolved within Strombidae, a robust phylogenetic framework is needed. In the present study, the complete mitochondrial genomes of Lentigo lentiginosus, Euprotomus aratrum, and Canarium labiatum were sequenced. The three newly sequenced mt genomes contained 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and several non-coding regions, indicating a similar pattern with respect to genome size, gene order, and nucleotide composition compared with those of other strombids reported before. Two different datasets derived from mitochondrial genes were constructed to resolve the internal phylogenetic relationships of Stromboidea and Strombidae. Within Stromboidea, the sister group formed by Clade I [Rostellariidae + (Seraphsidae + Strombidae)] and Clade II [Xenophoridae + (Struthiolariidae + Aporrhaidae)] were fully recovered and supported by morphological synapomorphies as previously suggested. The phylogenetic positions of L. lentiginosus, E. aratrum, and C. labiatum were confirmed within Strombidae, and several morphological similarities were observed corresponding to the present phylogeny. A correlation between strombids speciation events and paleoclimate change was presumed. Our results indicate that complete mt genomes would be a promising tool to reconstruct a robust phylogeny of Strombidae with an increased taxon sampling in the future.

Thomas B. White, Joseph W. Bull, Theodore P. Toombs et al.

Abstract In the USA, Species Conservation Banking is a prominent example of compensatory biodiversity impact mitigation, with an annual market value estimated at US$354.2 million. Species Conservation Banking represents a useful case study of a well‐established program that can provide empirical insights into the practicalities of implementing quantitative compensatory biodiversity mitigation on‐the‐ground. Using semi‐structured key‐informant interviews structured around well‐established technical challenges to compensatory mitigation, this study aimed to understand (i) how and why these challenges are or are not addressed in practice; and (ii) how these challenges relate to practical challenges faced by conservation banking stakeholders on‐the‐ground. Challenges identified included: (i) defining trading currencies and equivalence, (ii) regulatory and political uncertainty, (iii) regulatory agency capacity, will and knowledge, (iv) lack of policies, standards, and competition with other mitigation mechanisms, (v) long‐term uncertainty/longevity, and (vi) lack of species knowledge and data transparency. These challenges are numerous, diverse, interlinked and transdisciplinary, and collectively inhibit the ability of practitioners to resolve underlying technical challenges—a finding likely applicable to related biodiversity offset programs. To help address challenges and navigate this complexity, we formulate several recommendations for conservation banking stakeholders to improve the chances of beneficial biodiversity outcomes being achieved.

Santosh K. Chettri, Ghanashyam Sharma, Kailash S. Gaira et al.

Forests in the Barsey-Singalila transboundary area under Khangchendzonga landscape (KL) are facing pressures of resource uses. Despite continuous utilizations, complete data are lacking from the ground level. Socioeconomic, demographic, and forest use data were obtained by interviewing 233 households across two study locations. Forest product market survey was undertaken to determine prices of forest products. Resource dependence index was (0.60) high for both the locations. Alnus nepalensis is highly preferred fuel species with probability of use (0.791), and Rhododendron arboreum with probability of use (0.09) is considered as least preferred species. Relatively bigger village with more population is aggravating utilization pressures. Resource use at Gorkhey-Samanden is low (20% in case of fuelwood) as compared to the use at Ribdi-Bhareng (80% for fuelwood). Only preferred medicinal plants or wild edibles, namely, Yushania maling are collected regardless of their availability for fuelwood and other uses, which is causing more pressure on a small group of plants. A huge shortfall between resource demand and production indicates the possible extraction of resources from surrounding reserve forests. The results provide significant information on peoples dependency on forest resources and may be utilized for developing forest conservation policies for enhanced ecosystem services and livelihoods in the region.

Şükrü Ozan

How can a text corpus stored in a customer relationship management (CRM) database be used for data mining and segmentation? In order to answer this question we inherited the state of the art methods commonly used in natural language processing (NLP) literature, such as word embeddings, and deep learning literature, such as recurrent neural networks (RNN). We used the text notes from a CRM system which are taken by customer representatives of an internet ads consultancy agency between years 2009 and 2020. We trained word embeddings by using the corresponding text corpus and showed that these word embeddings can not only be used directly for data mining but also be used in RNN architectures, which are deep learning frameworks built with long short term memory (LSTM) units, for more comprehensive segmentation objectives. The results prove that structured text data in a CRM can be used to mine out very valuable information and any CRM can be equipped with useful NLP features once the problem definitions are properly built and the solution methods are conveniently implemented.

Edward S. Riddell, Jaco Nel, Johan van Tol et al.

The semi-arid conditions in savanna landscapes ensure that ephemeral drainage dominates the hydrological network in these dryland systems. Quantification of their hydrological processes is important to inform ecosystem understanding and future conservation efforts under a changing climate, and to provide guidance for restoration. By combining in situ hydrometric observations, hydrochemistry, remote sensing and a soil water balance model, we characterise the groundwater–surface water interactions in ephemeral low-order catchments of the granitoid regions of the southern Kruger National Park (KNP). Streams at the lowest orders are augmented by lateral interflows from the catena, although the second- and third-order stream reaches are conduits for groundwater recharge to the fractured rock aquifer; the soils of the crests and foot-slopes also show preferential flow, and are truly recharge soils, whilst the duplex soils of the midslopes clearly show their responsive nature to a low soil moisture deficit in the shallow horizons. Actual evaporation (aET) differed between catena elements with surprisingly little variation at third-order hillslopes, with the greatest overall aET at the first order. Meanwhile, soil water balances demonstrated a significant variation in storage of the riparian zones as a result of interflow from upslope and aET losses. Furthermore, data support broader-scale observations that groundwater recharge through the vadose zone to the fractured rock aquifer is dependent upon threshold antecedent precipitation conditions. Moderate precipitation events (5 mm/day – 35 mm/day) over a 2–3 week period initiate groundwater responses with a 2–3 month lag, whilst intense precipitation events (100 mm/day) are expressed within 2–3 weeks. Conservation implications: Understanding the lateral connectivity of terrestrial ecosystems to the ephemeral drainage network expressed via hydrological processes in these savanna landscapes is important to infer potential impacts of climate variability on the continued conservation of these ecosystems, both within and external to protected areas.

Yann Fragnière, Loïc Pittet, Benoît Clément et al.

Glacial relicts, especially those with very narrow habitat requirements, are particularly affected by global warming. We considered <i>Papaver occidentale</i>, a glacial relict endemic to the Western Prealps, belonging to the alpine poppy complex (<i>P. alpinum</i> aggr.), as a model taxon to study the actual status and potential future distribution of species restricted to particular microrefugia. For this study, all known localities were visited, each population was georeferenced and the number of individuals was estimated. Species Distribution Modelling (SDM) was used to evaluate the present and future potential distribution range and habitat suitability, taking into account the specificity of its habitat (calcareous screes). According to our study, there are globally 19 natural populations of <i>P. occidentale</i>, and a total of about 30,000 individuals. The taxon is a highly specialized alpine plant growing in the majority of natural sites between 1900 and 2100 m a.s.l. on north-facing screes. Predictions for the end of the 21st century indicate that a suitable area will significantly decrease (0–30% remaining). Under the most severe climatic scenarios (RCP 8.5), the species risks complete extinction. The long-term in situ conservation of <i>P. occidentale</i>, and all other taxa of the <i>P. alpinum</i> complex, is unlikely to be achieved without slowing global climate change. More generally, our fine-scale study shows that local environmental buffering of large-scale climate change in high-mountain flora may be very limited in specialised taxa of patchy environments such as screes.