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Critical role of water conditions in the responses of autumn phenology of marsh wetlands to climate change on the Tibetan Plateau
Get PDFAbstractThe Tibetan Plateau, housing 20% of China's wetlands, plays a vital role in the regional carbon cycle. Examining the phenological dynamics of wetland vegetation in response to climate change is crucial for understanding its impact on the ecosystem. Despite this importance, the specific effects of climate change on wetland vegetation phenology in this region remain uncertain. In this study, we investigated the influence of climate change on the end of the growing season (EOS) of marsh wetland vegetation across the Tibetan Plateau, utilizing satellite‐derived Normalized Difference Vegetation Index (NDVI) data and observational climate data. We observed that the regionally averaged EOS of marsh vegetation across the Tibetan Plateau was significantly (p < .05) delayed by 4.10 days/decade from 2001 to 2020. Warming preseason temperatures were found to be the primary driver behind the delay in the EOS of marsh vegetation, whereas preseason cumulative precipitation showed no significant impact. Interestingly, the responses of EOS to climate change varied spatially across the plateau, indicating a regulatory role for hydrological conditions in marsh phenology. In the humid and cold central regions, preseason daytime warming significantly delayed the EOS. However, areas with lower soil moisture exhibited a weaker or reversed delay effect, suggesting complex interplays between temperature, soil moisture, and EOS. Notably, in the arid southwestern regions of the plateau, increased preseason rainfall directly delayed the EOS, while higher daytime temperatures advanced it. Our results emphasize the critical role of hydrological conditions, specifically soil moisture, in shaping marsh EOS responses in different regions. Our findings underscore the need to incorporate hydrological factors into terrestrial ecosystem models, particularly in cold and dry regions, for accurate predictions of marsh vegetation phenological responses to climate change. This understanding is vital for informed conservation and management strategies in the face of current and future climate challenges
The dissociating effects of fear and disgust on Multisensory Integration in Autism: Evidence from evoked potentials
Get PDFBackground. Deficits in Multisensory Integration (MSI) in ASD have been reported repeatedly and have been suggested to be caused by altered long-range connectivity. Here we investigate behavioural and ERP correlates of MSI in ASD using ecologically valid videos of emotional expressions. Methods. In the present study, we set out to investigate the electrophysiological correlates of audiovisual MSI in young autistic and neurotypical adolescents. We employed dynamic stimuli of high ecological validity (500 ms clips produced by actors) that depicted fear or disgust in unimodal (visual and auditory), and bimodal (audiovisual) conditions. Results. We report robust MSI effects at both the behavioural and electrophysiological levels and pronounced differences between autistic and neurotypical participants. Specifically, neurotypical controls showed robust behavioural MSI for both emotions as seen through a significant speed-up of bimodal response time (RT), confirmed by Miller’s Race Model Inequality (RMI), with greater MSI effects for fear than disgust. Adolescents with ASD, by contrast, showed behavioural MSI only for fear. At the electrophysiological level, the bimodal condition as compared to the unimodal conditions reduced the amplitudes of the visual P100 and auditory P200 and increased the amplitude of the visual N170 regardless of group. Furthermore, a cluster-based analysis across all electrodes revealed that adolescents with ASD showed an overall delayed and spatially constrained MSI effect compared to controls. Conclusion. Given that the variables we measured reflect attention, our findings suggest that MSI can be modulated by the differential effects on attention that fear and disgust produce. We also argue that the MSI deficits seen in autistic individuals can be compensated for at later processing stages by a) the attention-orienting effects of fear, at the behavioural level, and b) at the electrophysiological level via increased attentional effort
Regional accents: Spontaneous biases towards speakers who sound like us
Get PDFAccents provide information about a speaker’s geographical, socio-economic, and ethnic background. An additional important variable in the social evaluation of accented speech is the listener’s own accent. Just as with any in-group marker, there is a preference for accented speakers that sound like us. Here we employed an auditory version of the implicit association test to quantify own-accent bias. At a Welsh university, we recruited two groups of participants born and raised in distinct regions within the UK, Wales and England. These regions have a long-standing history of national rivalry. In Experiments 1 and 2 we show that the magnitude of the implicitly measured own-accent bias in both groups was comparable to biases based on visible group membership (e.g., race). In addition, Experiment 2 shows that this implicitly measured bias was large compared to the explicitly reported preference. The effect sizes of the in-group preference reported here may have societal impact
Impact of Brexit Disclosure on Trade Credit
Get PDFThe Financial Reporting Council (FRC) issued guidance for companies regarding the disclosure of significant changes in principal risks. We explore the nexus between Brexit disclosure and trade credit decisions. Our findings suggest a positive relationship between Brexit disclosure and trade credit decisions; however, this relationship varies across industries. This variation indicates that UK companies are responsive to regulatory requirements and pressures, undertaking the necessary adjustments to minimise their exposure to Brexit-related risks
Coming to light: How effective are sediment gravity flows in removing fine suspended carbonate from reefs?
Get PDFCoral reefs are hard calcified structures, mainly found in warm tropical water. These ecosystems serve important roles as, for example, a source of food, shelter and nursery for different organisms, and in coastal protection. Reef‐building organisms have evolved to inhabit a narrow ecological niche and thus are particularly susceptible to rapid changes in their environment, for example, under predicted climate‐change scenarios. Anthropogenic climate change is widely accepted as the leading cause of rising ocean temperatures, sea water acidity and sedimentation rate, which all affect a coral's productivity, health and, to some extent, skeletal strength. High‐energy weather events, such as storms and hurricanes, can erode reefs, thereby increasing the amount of suspended sediment and consequently the turbidity of the water. The removal of suspended sediment from the reef is vital for the health of reef producers, and a natural process that removes suspended sediment from reefs are sediment gravity flows. A key factor that controls the ability of sediment gravity flows to transport sediment is cohesion, as cohesion determines the run‐out distance of a flow through changes in its rheological properties. This study examines the cohesive nature of sediment gravity flows laden with fine‐grained CaCO3. These gravity flows laden with mud‐grade calcite are compared with flows carrying non‐cohesive, silt‐sized, silica flour, weakly cohesive kaolinite clay and strongly cohesive bentonite clay, by means of laboratory experiments. The results of these experiments show that the mud‐grade calcite flows behave more akin to the silica‐flour flows by reaching maximum mobility at considerably higher volumetric suspended sediment concentrations (47% for silica flour and 53% for CaCO3) than the kaolinite and bentonite flows (22% for kaolinite and 16% for bentonite). Fine CaCO3 gravity flows can therefore be regarded as physically non‐cohesive, and their high mobility may constitute an effective mechanism for removing suspended sediment from coral reefs, especially at locations where a slope gradient is present, such as at the reef front and forereef. However, biological cohesion, caused by ‘sticky’ extracellular polymer substances produced by micro‐organisms, can render mud‐grade calcite cohesive and sediment gravity flows less mobile. The present study should therefore be seen as a first step towards a more comprehensive analysis of the efficiency of removal of suspended sediment from coral reefs
Modeling the Impact of Tides and Geothermal Heat Flux on the Climate of Early Earth
No full textOn early Earth increased rates of tidal energy dissipation are likely, but depend on the (unknown) distribution of continents. A stronger tidal heating could provide an additional energy source during times of substantially lower solar input. So far, the problem has been assessed in terms of the negligible contribution to Earth's global energy budget. Here we present a spatially resolved investigation of the impact of tidal heating, mixing, and geothermal heat on early Earth's climate. Using a random landmass distribution, tidal heating is calculated for three different rotation periods (12, 18, 24 hr) and fed into a climate model. For each rotation rate, three climate states with different atmospheric levels are simulated. We find that, depending on the climate state, tidal heating can affect regional ocean dynamics and sea-ice cover. The impact is strongest when tidal heating alters sea-ice dynamics and meridional heat transport close to the sea-ice edge, but its global impact remains negligible with only small global mean changes in ice cover (0.3%) and temperature (C). Adding tidal mixing and geothermal heat, however, leads to significant reduction in sea-ice cover of 11% and 19%, respectively, and thus to larger global warming. As we do not consider the dynamical effects of a higher rotation rate or different landmass distributions, this is only a first glimpse at the importance of tides for the climate of early Earth. Nevertheless, our results suggest that tides and geothermal heat are important for understanding regional climates and could have contributed to warming early Earth
The global loss of avian functional and phylogenetic diversity from anthropogenic extinctions
Get PDFHumans have been driving a global erosion of species richness for millennia, but the consequences of past extinctions for other dimensions of biodiversity—functional and phylogenetic diversity—are poorly understood. In this work, we show that, since the Late Pleistocene, the extinction of 610 bird species has caused a disproportionate loss of the global avian functional space along with ~3 billion years of unique evolutionary history. For island endemics, proportional losses have been even greater. Projected future extinctions of more than 1000 species over the next two centuries will incur further substantial reductions in functional and phylogenetic diversity. These results highlight the severe consequences of the ongoing biodiversity crisis and the urgent need to identify the ecological functions being lost through extinction. Human activities are a leading cause of species extinctions, either directly or indirectly, for millennia. Matthews et al. investigated how extinctions have affected global bird diversity, specifically in terms of birds’ traits and evolutionary history (see the Perspective by Kemp). About 530,000 years, and these species are more distinct in terms of their traits and lineages then would be expected by chance, especially those that went extinct before 1500 CE. Species, functional, and phylogenetic diversity losses are greatest on islands. Projected future extinctions are predicted to cause even more severe effects on avian functional and phylogenetic diversity, emphasizing a need for conservation efforts, especially on islands. —Bianca Lope
Respiratory and Cardiac Interoceptive Sensitivity in the First Two Years of Life
Get PDFSeveral recent theoretical accounts have posited that interoception, the perception of internal bodily signals, plays a vital role in early human development. Yet, empirical evidence of cardiac interoceptive sensitivity in infants to date has been mixed. Furthermore, existing evidence does not go beyond the perception of cardiac signals and focuses only on the age of 5–7months, limiting the generalizability of the results. Here, we used a modified version of the cardiac interoceptive sensitivity paradigm introduced by Maister et al. (2017) in 3-, 9-, and 18-month-old infants using cross-sectional and longitudinal approaches. Going beyond, we introduce a novel experimental paradigm, namely the iBREATH, to investigate respiratory interoceptive sensitivity in infants. Overall, for cardiac interoceptive sensitivity (total n= 135) we find rather stable evidence across ages with infants on average preferring stimuli presented synchronously to their heartbeat. For respiratory interoceptive sensitivity (total n = 120) our results show a similar pattern in the first year of life, but not at 18 months. We did not observe a strong relationship between cardiac and respiratory interoceptive sensitivity at 3 and 9 months but found some evidence for a relationship at 18 months. We validated our results using specification curve- and mega analytic approaches. By examining early cardiac and respiratory interoceptive processing, we provide evidence that infants are sensitive to their interoceptive signals
What is it like to be a diplomat? Reflections on Donald Griffin and emotion
Get PDFThis commentary addresses three aspects of Donald Griffin’s work: (1) his thoughtsbeyond cognition, on emotion; (2) his views on the earliest origins of mind, including primitiveforms of consciousness; and (3) his diplomatic use of memorable phrases to facilitate change