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This study introduces a global land cover clustering using an unsupervised algorithm, incorporating the novel step of filtering data to retain only temporally stable pixels before applying K-means clustering. Unlike previous approaches that did not assess the pixel-level temporal stability, this method provides more reliable clustering results. The K-means identified 160 distinct clusters, with Cluster 13 Global Temporally Stable (Cluster 13-GTS) showing significant improvements in temporal stability. Compared to Cluster 13 Global (Cluster 13-G) from earlier research, Cluster 13-GTS reduced the coefficient of variation by up to 1% and increased the number of calibration locations from 23 to over 50. This study also validated these clusters using TOA reflectance from ground-truth measurements collected at the Radiometric Calibration Network (RadCalNet) Gobabeb (RCN-GONA) site, incorporating data from Landsat 8, Landsat 9, Sentinel-2A, and Sentinel-2B. The GONA Extended Pseudo Invariant Calibration Sites (EPICS) GONA-EPICS cluster used for the validation provided statistically comparable mean TOA reflectance to RCN-GONA, with a reduced chi-square test indicating minimal differences within the cluster's uncertainty range. Notably, the difference in reflectance between RCN-GONA and GONA-EPICS was less than 0.023 units across all the bands. Although GONA-EPICS exhibited slightly higher uncertainty (6.4% to 10.3%) compared to RCN-GONA site (<5%), it offered advantages such as 80 potential calibration points per Landsat cycle and reduced temporal instability, and it provided alternatives to reduce the reliance on single sites like traditional PICS or RCN-GONA, making it a valuable tool for calibration efforts. These findings highlight the potential of the newly developed EPICS for radiometric calibration and stability monitoring of optical satellite sensors. Distributed across diverse regions, these global targets increase the number of calibration points available for any sensor in any orbital cycle, reducing the reliance on traditional PICS and offering more robust targets for radiometric calibration efforts. [ABSTRACT FROM AUTHOR]

Dried soil layer (DSL) is a phenomenon of deep soil desiccation caused by soil water content (SWC) deficiency. Relevant studies in the fragmented terrain of Chinese Loess Plateau (CLP) remain limited. In a typical slope‐gully unit near the Liudaogou catchment, SWC was measured using neutron probes on 19 occasions at 15 observational locations. In order to reveal the temporal stability and elimination degree of DSLs, available soil moisture (ASM) and DSL were estimated by representative sites which were determined through the temporal stability method, and the reliability of simulating mean condition of the study area via representative locations was assessed. Results show that: (1) the dynamics of DSL was characterised by complexity and diversity. The ASM within the DSL (DSL‐ASM), ASM within the sandwiched DSL (SDSL‐ASM) and quantitative index (QI) varied within the range of 2.75%–3.11%, 2.98%–4.22% and 0.254–0.356, respectively. (2) The possibility of development and recovery for DSL and SDSL in deep layers were less than that in shallow layers. The maximum depth of DSL (DSLMD) was significantly and negatively related to the standard deviation of relative difference (SDRD) of DSL‐ASM, the maximum depth of SDSL (SDSLMD) was negatively related to the SDRD of SDSL‐ASM. (3) The prediction results of ASM above 300 cm depth were more accurate than other layers (R2 = 0.89). The DSL‐ASM had more accurate ability of prediction than SDSL‐ASM and QI. On the analysis of time stability characteristics of ASM and DSLs, the locations of A2 and C3 can better represent the mean conditions of ASM at three and four soil layers, respectively. C2, A1 and A1 can better represent the average levels of DSL‐ASM, SDSL‐ASM and QI, respectively (R2 = 0.43, 0.14 and 0.18). (4) The restoration degrees of DSLs mainly showed no elimination and slight elimination, the DSLs cannot be completely eliminated within a short time. We proposed that scientific regulation of SWC can alleviate the formation and development of DSLs at a certain extent, and provide the possibility for DSLs nonoccurrence. [ABSTRACT FROM AUTHOR]

High fatality rates in frequent rear-end crashes have underscored significant safety concerns in China. This study aims to explore the mechanisms and determinants of rear-end crashes, with a particular focus on the factors influencing crash severity during weekdays and weekends (W-W). Employing the Random Parameter Logit Model (RPLM) to account for variability in data, we analyzed W-W rear-end crashes on the Beijing-Shanghai Expressway in Jiangsu province from 2017 to 2019, considering three severity levels: no injury, minor injury, and severe injury. Our comprehensive analysis covered variables from temporal, roadway, vehicle, crash, and environmental categories, alongside calculating the marginal effects of each significant variable on crash severity. Findings reveal temporal instability over the three-year period and notable differences in W-W crash severity. Out of all variables, four displayed random parameter characteristics, indicating potential interactions that influence crash outcomes. Specifically, our results indicate that rear-end crashes involving three or more vehicles on bridges are more likely to result in casualties. Interchange segments typically saw no injuries in two-vehicle crashes. Speeding during winter or on sunny days significantly increases the risk of injuries and fatalities. Furthermore, rear-end crashes in interchange areas during winter are particularly prone to causing injuries. These findings offer guidance for the development of effective safety countermeasures targed at different pediods. [ABSTRACT FROM AUTHOR]

Soil moisture is a critical factor for vegetation restoration in arid regions. Poorly planned artificial sand-fixing vegetation systems often exacerbate soil moisture depletion, leading to further degradation. In this study, soil moisture content at various depths was continuously monitored from June to October 2023 in four key community plots—Corethrodendron scoparium, Calligonum mongolicum, and Artemisia ordosica, and bare sand—in a 31-year-old revegetated area located on the northeastern edge of the Tengger Desert. We analyzed the distribution and dynamic changes of soil moisture across the different and evaluated its temporal stability. The representative soil moisture depth was determined by using the coefficient of determination (R²) and the Nash-Sutcliffe efficiency (NSE). The results showed significant differences in soil moisture among the four plots. The bare sand plot had the highest soil water storage in the 0-200 cm layer, at 46.37 mm. In contrast, the Corethrodendron scoparium, Calligonum mongolicum, and Artemisia ordosicaa plots had similar soil water storage values ranging from 33.50 to 33.67 mm, indicating that vegetation restoration has increased soil moisture absorption by an average of 27.4%. Analysis using relative difference and Spearman rank correlation methods revealed varying levels of temporal stability in soil moisture across different soil depths and plots. The Corethrodendron scoparium and bare sand plots showed higher temporal stability compared to the Calligonum mongolicum and Artemisia ordosica plots. The representative depths of temporal stability for the four plots were determined to be 100 cm, 150 cm, 20 cm, and 100 cm, respectively. [ABSTRACT FROM AUTHOR]

Background: Assessing the relationships between spatial and temporal structures and functions of plant communities is an effective way to understand the changing dynamics of plant communities in specific environments. In this study, we investigated the response of structural and functional stabilities of plant communities to stocking rate in the desert steppe over a 16-year grazing period as the research background. Methods: We used classical statistical methods to investigate the quantitative characteristics of plant communities over time (2014–2019) and space (2017–2019) at four stocking rates (control, CK, 0 sheep·ha–1·month–1; light grazing, LG, 0.15 sheep·ha–1·month–1; moderate grazing, MG, 0.30 sheep·ha–1·month–1; heavy grazing, HG, 0.45 sheep·ha–1·month–1) in the Stipa breviflora desert steppe of Inner Mongolia. We then examined the relationship between structural and functional stability of plant communities. Results: On the spatial scale, the structural stability of plant community was the highest in the LG treatment and the lowest in the MG treatment. The functional stability of plant community was the highest in the MG treatment and the lowest in the HG treatment. On the temporal scale, the structural stability of plant community was the highest in the MG treatment and the lowest in the LG treatment. The functional stability of plant community was the highest in the LG treatment and the lowest in the HG treatment. Affected by the stocking rate, the structural stability of plant community fluctuated more widely on the spatial scale and its functional stability varied more widely on the temporal scale. Nonetheless, the functional stability of the plant community is more responsive to the stocking rate. Conclusions: Our findings suggest that influenced by the disturbance of stocking rate, the structural stability of plant community is more significant than the functional stability in the desert grassland ecosystem, which lays a solid foundation for the study of ecosystem stability. [ABSTRACT FROM AUTHOR]

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This study aimed to identify and compare the risk factors associated with motorcycle crash severity during both daytime and nighttime, for single and multivehicle incidents in Thailand using 2021–2024 data. The research employed the XGBoost (Extreme Gradient Boosting) method for statistical analysis and extensively examined the temporal instability of risk factors. The results highlight the importance of features impacting the injury severity of roadway collisions across various conditions. For single motorcycle crashes, the key risk factors included speeding, early morning incidents, off-road events, and long holidays. In multivehicle crashes, rear-end collisions, interactions with large vehicles, and collisions involving other motorcycles or passenger cars were linked to increased injury severity. The findings indicate that the important factors associated with motorcyclist injury severity in roadway crashes vary depending on the type of crash and time of day. These insights are valuable for policymakers and relevant authorities in developing targeted interventions to enhance road safety and mitigate the incidence of severe and fatal motorcycle crashes. [ABSTRACT FROM AUTHOR]

Climate change is impacting marine species, leading to shifts in their distribution to higher latitudes and to deeper locations. Parasite communities are dynamic systems influenced by biotic and abiotic factors, making them valuable tools for studying ecological processes of their hosts. This work aims to assess possible changes in parasite structure that occurred in the northern stock of Cynoscion guatucupa in the Argentine Sea, over approximately 25 years, by using parasites as tags in a region characterized as a hotspot of significant warming in recent decades. Parasite assemblages of adult and juvenile fish from two periods caught at two regions of the Argentine Sea were analyzed. Species richness remained relatively constant across samples, although four of the eight compared species from juvenile fish showed significant increases in prevalence, while for adults three species decreased. Differences in parasite assemblages were significant between periods, but not between regions, indicating that the stock structure has apparently remained stable in recent years, even under a warming process that, in turn, seems to have affected its parasite assemblages which however, continue showing homogeneous parasitological attributes throughout the habitats. Most results indicate that changes in parasite burdens are not related to the population density or geographic distribution of C. guatucupa, but to changes in temperature, salinity or in the density of top predators. Parasites seem to have felt the impact of global change before their host, thus, they can be considered early sentinels to monitor the stability and distribution of this important resource. [ABSTRACT FROM AUTHOR]

While the gut microbiome has been intensively investigated for more than twenty years already, its role in various disorders remains to be unraveled. At the same time, questions about what changes in the gut microbiota can be considered as normal or pathological and whether communities are able to recover after exposure to negative factors (diseases, medications, environmental factors) are still unclear. Here, we describe changes in the gut microbiota composition and the content of short-chain fatty acids in adult healthy volunteers (n = 15) over a 24 month-period. Intraindividual variability in gut microbial composition was 40%, whereas the short chain fatty acids profile remained relatively stable (2-year variability 20%, inter-individual 26%). The changes tend to accumulate over time. Nevertheless, both short-term and long-term changes in the gut microbiome composition were significantly smaller within individuals than interindividual differences (two-year interindividual variability was 75%). Seasonal changes in gut microbiota were found more often in autumn and spring involving the content of minor representatives (less than 1.5% of the community in average) in the phyla Actinobacteriota, Firmicutes and Proteobacteria. [ABSTRACT FROM AUTHOR]

This study explores the temporal instability and non-transferability of the determinants affecting injury severities of pedestrians struck by motorcycles and non-motorcycles. Using the pedestrian-vehicle crash data in Rawalpindi, Pakistan, over three years (2017–2019), three possible crash injury severity categories (minor injury, severe injury, and fatal injury) are estimated using alternative models to account for unobserved heterogeneity. These are a random-parameters multinomial logit (RP-ML) model with heterogeneity in means and variances and a latent-class multinomial logit (LC-ML) model with class probability functions. Temporal instability and non-transferability in the effects of explanatory variables are confirmed using a series of likelihood ratio tests based on the two alternative models. Various variables are observed to determine pedestrian-injury severities, and the estimation results show significant temporal instability and non-transferability in both RP-ML and LC-ML models. However, several explanatory variables produce relatively temporally stable and transferable effects, providing valuable insights to implement effective countermeasures from a long-term perspective. Moreover, out-of-sample predictions are simulated to confirm the temporal instability and non-transferability. At the same time, the LC-ML models produce higher differences for temporal instability and lower differences for non-transferability compared to the RP-ML model. Understanding and depth comparing the estimation results, likelihood ratio tests, and out-of-sample predictions using alternative models is a promising direction for future research to explore how the observed and unobserved heterogeneity can be estimated in terms of temporal instability and non-transferability. [ABSTRACT FROM AUTHOR]

The Pacific oyster Crassostrea gigas, one of the most exploited molluscs in the world, has suffered from massive mortality in recent decades, and the occurrence mechanisms have not been well-characterized. In this study, to reveal the relationship of associated microbiota to the fitness of oysters, temporal dynamics of microbiota in the gill, hemolymph, and hepatopancreas of C. gigas during April 2018–January 2019 were investigated by 16S rRNA gene sequencing. The microbiota in C. gigas exhibited tissue heterogeneity, of which Spirochaetaceae was dominant in the gill and hemolymph while Mycoplasmataceae enriched in the hepatopancreas. Co-occurrence network demonstrated that the gill microbiota exhibited higher inter-taxon connectivity while the hemolymph microbiota had more modules. The richness (Chao1 index) and diversity (Shannon index) of microbial community in each tissue showed no significant seasonal variations, except for the hepatopancreas having a higher richness in the autumn. Similarly, beta diversity analysis indicated a relatively stable microbiota in each tissue during the sampling period, showing relative abundance of the dominant taxa exhibiting temporal dynamics. Results indicate that the microbial community in C. gigas showed a tissue-specific stability with temporal dynamics in the composition, which might be essential for the tissue functioning and environmental adaption in oysters. This work provides a baseline microbiota in C. gigas and is helpful for the understanding of host-microbiota interaction in oysters. [ABSTRACT FROM AUTHOR]

A substantial body of empirical evidence suggests that anthropogenic disturbance can affect the structure and function of grassland ecosystems. Despite this, few studies have elucidated the mechanisms through which grazing and mowing, the two most widespread land management practices, affect the stability of natural grassland communities. In this study, we draw upon 9 years of field data from natural grasslands in northern China to investigate the effects of gazing and mowing on community stability, specifically focusing on community aboveground net primary productivity (ANPP) and dominance, which are two major biodiversity mechanisms known to characterize community fluctuations. We found that both grazing and mowing reduced ANPP in comparison to areas enclosed by fencing. Grazing reduced community stability by increasing the likelihood of single‐species dominance and decreasing the relative proportion of nondominant species. In contrast, mowing reduced the productivity of the dominant species but increased the productivity of nondominant species. As a consequence, mowing improved the overall community stability by increasing the stability of nondominant species. Our study provides novel insight into understanding of the relationship between community species fluctuation‐stability, with implications for ecological research and ecosystem management in natural grasslands. [ABSTRACT FROM AUTHOR]

Calibrating optical sensors has become a priority to maintain data quality and ensure consistency among sensors from different agencies. Achieving and monitoring radiometric calibration often involves the identification of temporally stable targets on the Earth's surface. Although some locations across North Africa have traditionally been used as primary targets for calibration purposes, it is crucial to explore alternative options to account for potential changes in these sites over time. This study conducted a global assessment of pixel-level temporal stability using Landsat 8 OLI data, with the primary goal of identifying regions suitable for global radiometric calibration efforts. This work followed a two-stage approach, including the testing and selection of an effective combination of statistical tests to differentiate between temporally stable and unstable pixels and the generation of a worldwide mosaic of temporally stable pixels through a per-pixel statistical analysis employing a combination of Spearman's rho and Pettitt's test for assessing long-term trends and detecting change points. Notably, comparing the temporal mean top-of-atmosphere (TOA) reflectance before and after applying the generated temporal filter to a site with documented unstable pixels revealed a substantial reduction in mean variation, up to 6%. In addition, slopes observed in the pre-filter mean TOA reflectance, ranging between −0.002 and −0.005, became zero or near-zero and statistically insignificant after the temporal filter was applied, demonstrating a reduction in total uncertainties by 3 to 4%. These findings evidence the potential of this work, placing it as a potential foundation in the continuous search to identify additional targets for global radiometric calibration efforts. [ABSTRACT FROM AUTHOR]

In recent decades, there has been increasing interest in studying the variability in soil water properties and, specifically, the spatiotemporal variability in the soil water content. This is motivated by the notable theoretical and applied research interests in soil moisture dynamics and their implications for many natural processes. This study aimed to study whether there are variations in the spatial pattern of the temporal stability of soil moisture over time and to analyze the possible influences of certain hydroclimatic (soil water content, precipitation, and evapotranspiration) and soil factors (texture, bulk density, and organic matter content) on these variations. This study was conducted within the Soil Moisture Measurement Stations Network of the University of Salamanca (REMEDHUS, Spain) under Mediterranean conditions, with daily surface moisture data (0-5 cm depth) obtained from 20 stations for the 2006-2023 period. The results showed differences between the average pattern obtained with the 18-year data series and that obtained with the data series for each year. In more than half of the years studied, the representative station differed from that derived from the average pattern. The mean annual precipitation and summer precipitation characteristics seem to be the main factors influencing the variability in the spatial pattern of the temporal stability of soil moisture. [ABSTRACT FROM AUTHOR]

Objective: The aims of this study were to examine changes in habitual optimism over a six-year period and to analyze the relationship between changes in optimism and changes in other quality of life-related variables. Method: A randomly selected community sample of the German adult general population (N  =  4,965) was surveyed twice, with a time interval of 6.04  years. Results: During the course of the 6  years, the mean score of the LOT-R total scale improved (effect size d  =  0.11). The temporal stability in terms of the test– retest correlation was r  =  0.61 for the total sample. There were only marginal gender differences in this temporal stability, however, the stability in the oldest age group ≥70  years (r  =  0.50) was lower than the stability of the other age groups. The cross-sectional correlations showed clear relationships between optimism on the one hand and quality of life, life satisfaction, social support, and low levels of anxiety and physical complaints on the other. The corresponding longitudinal correlations between changes in optimism and changes in the other variables were less pronounced, but in the same direction. Conclusion: The study confirmed the applicability of the LOT-R in longitudinal studies. In samples with participants of 70  years and above, the limited stability in the optimism assessments needs to be considered in clinical practice and epidemiologic research. [ABSTRACT FROM AUTHOR]

Asymmetric seasonal warming, characterized by more pronounced temperature increases in winter than in summer, has become a critical feature of global warming, especially in cold and high-altitude regions. Previous studies have primarily focused on year-round warming, while comparatively less attention was paid to winter warming. However, a significant knowledge gap exists regarding the impacts of winter warming on ecosystem functions. To address this, we conducted an 8-year manipulated warming experiment in an alpine grassland on the Tibetan Plateau, employing three treatments: no warming, year-round warming and winter warming. We found that neither year-round warming nor winter warming significantly alters species richness at the community level. Notably, community biomass stability was maintained via species asynchrony. However, warming exerted significant effects on the plant abundance groups (dominant, common and rare species). Specifically, winter warming enhanced the stability of dominant species by increasing species asynchrony of dominant species, as the compensatory dynamics occurred between the grass and forbs. In contrast, year-round warming reduced the stability of common species, correlated with an increase in species richness and a decline in asynchrony among common species. Thus, our study underscores the capacity of alpine grassland to maintain community biomass stability via asynchrony dynamics of species under different warming conditions, although the stability of different abundance groups would be changed. Importantly, our results provide valuable insights for understanding the alpine grassland ecosystem on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

In this study, we explored the temporal stability of the Personality Assessment Inventory (PAI), which has not been comprehensively reexamined since it was first published. Our three specific aims were to determine the utility of PAI indicators of basic protocol validity (inconsistent responses [ICN] and highly unusual/unlikely responses [INF]) in identifying suspect responding; calculate the stability coefficients for each PAI scale and subscale across 3-, 6-, and 9-week spans; and explore whether profile stability across four measurements could be prospectively predicted. We administered the PAI to a sample of undergraduates (N = 579) at four separate timepoints. ICN and INF effectively identified likely attriters and inconsistent responders. All PAI full scales and subscales evidenced good test–retest reliability, with some small exceptions. Finally, all PAI clinical scales were correlated with profile instability although many of these correlations were no longer significant when controlling for mean clinical elevation of the profile. We interpreted these results as evidence for the utility of PAI validity scales, the temporal reliability of the PAI, and the role of psychopathology in response variability over time. We also discussed some preliminary evidence that this variability can be prospectively predicted, suggesting that it in part reflects substantive changes rather than random error variance. [ABSTRACT FROM AUTHOR]

A lower helmet-wearing rate and overspeeding in Pakistan are critical risk behaviors of motorcyclists, causing severe injuries. To explore the differences in the determinants affecting the injury severities among helmeted and non-helmeted motorcyclists in motorcycle crashes caused by overspeeding behavior, single-vehicle motorcycle crash data in Rawalpindi city for 2017–2019 is collected. Considering three possible crash injury severity outcomes of motorcyclists: fatal injury, severe injury and minor injury, the rider, roadway, environmental, and temporal characteristics are estimated. To provide a mathematically simpler framework, the current study introduces parsimonious pooled random parameters logit models. Then, the standard pooled random parameters logit models without considering temporal effects are also simulated for comparison. By comparing the goodness of fit measure and estimation results, the parsimonious pooled random parameters logit model is suitable for capturing the temporal instability. Then, the non-transferability among helmeted and non-helmeted overspeeding motorcycle crashes is illustrated by likelihood ratio tests and out-of-sample prediction, and two types of models provide robust results. The marginal effects are also calculated. Several variables, such as age, cloudy and weekday indicators illustrate temporal instability. Moreover, several variables are observed to only show significance in non-helmeted models, showing non-transferability across helmeted and non-helmeted models. More educational campaigns, regulation and enforcement, and management countermeasures should be organized for non-helmeted motorcyclists and overspeeding behavior. Such findings also provide research reference for the risk-compensating behavior and self-selected group issues under overspeeding riding considering the usage of helmets. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is a key factor that determines the stability and functioning of desert ecological systems, but has been rarely studied due to the difficulty of sampling. The characterization of the temporal stability of soil moisture (SM TS) and its statistical parameters is much needed. To identify suitable locations to estimate SM status for the study area, and obtain greater insights into the SM TS of the Horqin Sand Land, SM was measured in a fixed dune (FD) over a depth profile of 0–1 m and on 14 occasions between May and July 2021. These data were combined with soil property and precipitation measurements to assess the SM TS and determine the optimal locations that could represent the mean SM of the area. Results indicated that (1) the mean SM of FD varied from 1.98% to 6.73%, with minimal spatial variation (mean standard deviation (STD) < 3%; mean coefficient of variation (CV) ranging between 42% and 56%). (2) SM continually decreased over time until considerable precipitation occurred. Temporal dynamics decreased with increasing soil depth. Further, only larger precipitation events (> 20 mm) led to significant SM increases. In deeper soil layers (> 60 cm), the SM response exhibited a lag. (3) The relationship between STD and mean SM indicated that SM becomes more variable under wetter conditions, such that SM increases were associated with CV increases in this region. (4) The Spearman's rank correlation coefficient (RS) values between different sampling dates indicated that most of the relationships were significant (p < 0.05), especially for soils in the 60–100 cm layer. (5) The mean values of mean relative differences (MRD) were smaller for soils < 40 cm and the mean corresponding standard deviation of MRD (SDRD) values were smaller for soils < 60 cm, indicating that SM tended to be more stable in deeper soil layers. (6) Linear regression analyses between the estimated means obtained from the identified locations and the actual field means led to the identification of the best representative SM locations for the 0–20, 20–40, 40–60, 60–80, and 80–100 cm layers at locations 8, 16, 8, 11, and 6, respectively. (7) The accumulated temporal stability index (ITS) of SM for different soil layers suggested that the 12th location (with a minimum ITS value) was the most representative location to approximate the mean SM of different soil layers in the FD. However, linear regression analyses of the SM between the actual field mean and that of the 12th representative location revealed a satisfactory fit only for soil layers above 40 cm. This study contributes to our understanding of SM patterns in arid environments, which have important implications for ground sampling design and hydro-logic modeling. [ABSTRACT FROM AUTHOR]

The semi-Lagrangian Reproducing Kernel (SL RK) has been successfully applied to simulations of extreme deformation problems thanks to intensive advancements in meshfree methods in recent decades. The SL RK shape function is constructed centered at a material point with a fixed spatial radius, and therefore it is a time-dependent function. When the SL RK is introduced in the weak form of the equation of motion, the time derivatives of SL RK lead to convective terms in the semi-discrete equation, significantly reducing the computational efficiency and accuracy. This paper presents a novel approximation scheme in which displacement, velocity, and acceleration are approximated by the same SL RK at a time instant. Consequently, the proposed concurrent SL RK formulation avoids the need to compute the convective terms, offering an effective numerical solution for high-strain rate dynamic problems. Furthermore, an eigenvalue analysis is performed on the semi-discrete equation of motion to investigate the temporal stability of the concurrent SL RK formulation. A comprehensive study of the eigenvalue and critical time step is conducted to identify the effective parameters for the stability of the system. Several manufactured dynamic problems are studied to validate the analytical estimate. The estimated analytical eigenvalue and the critical time step are consistent with the numerical result. [ABSTRACT FROM AUTHOR]

Recent extremes of flood and drought across Australia have raised questions about the recurrence of such rare events and highlighted the importance of understanding multi-decadal climate variability. However, instrumental records over the past century are too short to adequately characterise climate variability on multi-decadal and longer timescales or robustly determine extreme event frequencies and their duration. Palaeoclimate reconstructions can provide much-needed information to help address this problem. Here, we use the 600-year hydroclimate record captured in the eastern Australian and New Zealand Drought Atlas (ANZDA) to analyse drought and pluvial frequency trends for East Australian Natural Resource Management (NRM) clusters. This partitioning of the drought atlas grid points into recognised biophysical areas (i.e. NRM clusters) revealed their differences and similarities in drought intensity and pluvial events over time. We find sustained multi-decadal periods of a wet–dry geographic 'seesaw' between eastern to central and southern NRMs (e.g. 1550–1600 CE and 1700–1750 CE). In contrast, other periods reveal spatially consistent wetting (e.g. 1500–1550 CE) or drying (e.g. 1750–1800 CE). Emerging hot spot analysis further shows that some areas that appear naturally buffered from severe drought during the instrumental period have a greater exposure risk when the longer 600-year record is considered. These findings are particularly relevant to management plans when dealing with the impacts of climate extremes developed at regional scales. Our results demonstrate that integrating and extending instrumental records with palaeoclimate datasets will become increasingly important for developing robust and locally specific extreme event frequency information for managing water resources. [ABSTRACT FROM AUTHOR]

Remote sensing technology is an essential tool for tracking human-induced alterations on the water cycle, among which irrigation prevails. The possibility of obtaining detailed and accurate information on the actual irrigation extent through remote-sensing-based approaches is of paramount importance for water resources management. In this study, an update of the TSIMAP (Temporal-Stability-derived Irrigation MAPping) method, originally developed with satellite soil moisture as an input, is proposed. To demonstrate that the flexibility of the approach does not affect its main strength point (i.e., good accuracy in the face of high simplicity for users), a dual analysis relying on 1 km NDVI (Normalised Difference Vegetation Index) instead of soil moisture is carried out over the Ebro basin (Spain); data delivered by the Copernicus Global Land Service (CGLS) are used. First, results of this work are compared with outcomes from the method's original implementation obtained over a focus area (denominated "Ebro_CATAR") through satellite soil moisture. In the proposed configuration relying on NDVI, an overall accuracy (OA) up to 93% is found. Results highlight an increase in OA ranging from +2% to +6% depending on the validation strategy with respect to the TSIMAP implementation relying on soil moisture. Then, a basin-scale application is performed, providing performances still satisfactory (OA = 75%) notwithstanding a higher degree of heterogeneity. [ABSTRACT FROM AUTHOR]

It is well known that biodiversity positively affects ecosystem functioning, leading to enhanced ecosystem stability. However, this knowledge is mainly based on analyses using single ecosystem functions, while studies focusing on the stability of ecosystem multifunctionality (EMF) are rare. Taking advantage of a long‐term grassland biodiversity experiment, we studied the effect of plant diversity (1–60 species) on EMF over 5 years, its temporal stability, as well as multifunctional resistance and resilience to a 2‐year drought event. Using split‐plot treatments, we further tested whether a shared history of plants and soil influences the studied relationships. We calculated EMF based on functions related to plants and higher‐trophic levels. Plant diversity enhanced EMF in all studied years, and this effect strengthened over the study period. Moreover, plant diversity increased the temporal stability of EMF and fostered resistance to reoccurring drought events. Old plant communities with shared plant and soil history showed a stronger plant diversity–multifunctionality relationship and higher temporal stability of EMF than younger communities without shared histories. Our results highlight the importance of old and biodiverse plant communities for EMF and its stability to extreme climate events in a world increasingly threatened by global change. [ABSTRACT FROM AUTHOR]

We recently showed that subjects can learn motion state-dependent changes to motor output (temporal force patterns) based on explicit visual feedback of the equivalent force field (i.e., without the physical perturbation). Here, we examined the spatiotemporal properties of this learning compared with learning based on physical perturbations. There were two human subject groups and two experimental paradigms. One group (n = 40) experienced physical perturbations (i.e., a velocity-dependent force field, vFF), whereas the second (n = 40) was given explicit visual feedback (EVF) of the force-velocity relationship. In the latter, subjects moved in force channels and we provided visual feedback of the lateral force exerted during the movement, as well as the required force pattern based on movement velocity. In the first paradigm (spatial generalization), following vFF or EVF training, generalization of learning was tested by requiring subjects to move to 14 untrained target locations (0- to ±135-around the trained location). In the second paradigm (temporal stability), following training, we examined the decay of learning over eight delay periods (0 to 90 s). Results showed that learning based on EVF did not generalize to untrained directions, whereas the generalization for the vFF was significant for targets - 45-away. In addition, the decay of learning for the EVF group was significantly faster than the FF group (a time constant of 2.72 ± 1.74 s vs. 12.53 ± 11.83 s). Collectively, our results suggest that recalibrating motor output based on explicit motion state information, in contrast to physical disturbances, uses learning mechanisms with limited spatiotemporal properties. [ABSTRACT FROM AUTHOR]

Soil moisture is important for understanding climate, water resources, water storage, and land use management. This study used Sentinel-2 (S-2) satellite optical data to retrieve surface soil moisture at a 10 m scale on grassland sites with low hydraulic conductivity soil in a climate dominated by heavy rainfall. Soil moisture was estimated after modifying the Optical Trapezoidal Model to account for mixed land cover in such conditions. The method uses data from a short-wave infra-red band, which is sensitive to soil moisture, and four vegetation indices from optical bands, which are sensitive to overlying vegetation. Scatter plots of these data from multiple, infrequent satellite passes are used to define the range of surface moisture conditions. The saturated and dry edges are clearly non-linear, regardless of the choice of vegetation index. Land cover masks are used to generate scatter plots from data only over grassland sites. The Enhanced Vegetation Index demonstrated advantages over other vegetation indices for surface moisture estimation over the entire range of grassland conditions. In poorly drained soils, the time lag between satellite surface moisture retrievals and in situ sensor soil moisture at depth must be part of the validation process. This was achieved by combining an approximate solution to the Richards' Equation, along with measurements of saturated and residual moisture from soil samples, to optimise the correlations between measurements from satellites and sensors at a 15 cm depth. Time lags of 2–4 days resulted in a reduction of the root mean square errors between volumetric soil moisture predicted from S-2 data and that measured by in situ sensors, from ~0.1 m3/m3 to <0.06 m3/m3. The surface moisture results for two grassland sites were analysed using statistical concepts based upon the temporal stability of soil water content, an ideal framework for the intermittent Sentinel-2 data in conditions of persistent cloud cover. The analysis could discriminate between different natural drainages and surface soil textures in grassland areas and could identify sub-surface artificial drainage channels. The techniques are transferable for land-use and agricultural management in diverse environmental conditions without the need for extensive and expensive in situ sensor networks. [ABSTRACT FROM AUTHOR]

Questions: Although the relationships between biodiversity and individual ecosystem functions under resource enrichment have been extensively studied, there is limited understanding of how resource‐induced changes affect ecosystem multifunctionality and its temporal stability, along with the underlying biological mechanisms. Location: Inner Mongolia, China. Methods: We investigated the impact of biodiversity mechanisms on ecosystem multifunctionality and its temporal stability through a 3‐year field experiment. This experiment involved augmenting growing season precipitation and nitrogen deposition, conducted in a typical steppe ecosystem of Inner Mongolia alongside regular mowing. Results: Our findings revealed that the addition of water (W) and nitrogen (N) had varying effects on ecosystem multifunctionality and its temporal stability. The combination of N and W additions enhanced ecosystem multifunctionality, whereas both W and N + W additions promoted the temporal stability of ecosystem multifunctionality. Structural equation modeling demonstrated that the community‐weighted mean height, in response to nitrogen addition, played a key role in enhancing ecosystem multifunctionality. By contrast, increased species asynchrony because of water addition and greater functional diversity in terms of leaf area contributed to heightened temporal stability of ecosystem multifunctionality. Furthermore, the positive effects of community‐weighted mean height on ecosystem multifunctionality exhibited a gradual increase with rising threshold levels. Conclusions: Our study provides the first evidence of the independent effects of selection, exemplified by community‐weighted mean and complementarity, represented by factors such as species richness, functional diversity and species asynchrony on both ecosystem multifunctionality and its temporal stability. This underscores how global change factors can directly influence ecosystem multifunctionality and its temporal stability while also indirectly modulating biodiversity effects in the short term. Overall, our findings underscore the vital role of biodiversity conservation in enhancing grassland management and the delivery of ecosystem services in the context of global change, particularly in regions subject to extensive mowing. [ABSTRACT FROM AUTHOR]

There is growing evidence that land‐use management practices such as livestock grazing can strongly impact the local diversity, functioning, and stability of grassland communities. However, whether these impacts depend on environmental condition and propagate to larger spatial scales remains unclear. Using an 8‐year grassland exclosure experiment conducted at nine sites in the Tibetan Plateau covering a large precipitation gradient, we found that herbivore exclusion increased the temporal stability of alpine grassland biomass production at both the local and larger (site) spatial scales. Higher local community stability was attributed to greater stability of dominant species, whereas higher stability at the larger scale was linked to higher spatial asynchrony of productivity among local communities. Additionally, sites with higher mean annual precipitation had lower dominant species stability and lower grassland stability at both the spatial scales considered. Our study provides novel evidence that livestock grazing can impair grassland stability across spatial scales and climatic gradients. [ABSTRACT FROM AUTHOR]

Purpose: Entrepreneurial intention (EI) has been studied prolifically, as a precursor to entrepreneurial action, and a desired outcome of entrepreneurship education. Yet, the paucity of extant studies that analyze its temporal stability has been noted. This paper aims to address this gap by studying the temporal stability of EI, investigating its persistence as an attitudinal state over time. Design/methodology/approach: A series of intraindividual and group-level longitudinal analyses were undertaken, over an 11-year period, using a student sample from Portugal. The authors highlight the magnitude of EI change over time, where item-structure, relative and absolute stability and group and individual-level EI changes are all considered. Findings: Results indicate an initially strong to moderate EI item-structure stability and relative stability over the first five years, with moderate signs of deterioration. This deterioration becomes even more pronounced across the full 11-year period. Regarding EI absolute stability, while college students (as a group) did not display a general tendency to develop higher or lower EI during the first five years, a small deterioration was found over the 11-year period. At the individual level, EI instability was detected, and this increased with time. Finally, the exploratory results suggest that entrepreneurship education may buffer the deterioration of EI. Practical implications: The findings provide a more nuanced reasoning for dampened EI–entrepreneurial behavior associations and highlight key determinants of EI change, which can inform educational experts and policymakers. Originality/value: The legitimacy of the EI field lays heavily on the existence of a stable EI construct and a strong relationship between intentions and behavior. The methodology provides a new and more complete picture of EI's temporal stability. [ABSTRACT FROM AUTHOR]

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Entrepreneurial identity represents a powerful motivating force that can help explain individuals' entrepreneurial activity and has been found to be relevant to several new business venturing decisions. Although identity may entail some degree of temporal stability, personal agency and social interactions may change it. While understanding entrepreneurial identity formation and development is a promising research topic, longitudinal analyses are lacking. In this study, we propose a longitudinal model in which intra-individual entrepreneurial identity aspirations exhibit path dependency, and test different types of entrepreneurial experiences as mediators affecting this relationship. Applying structural equation modeling to a longitudinal sample composed of individuals formerly enrolled in higher education programs, we found that past entrepreneurial identity aspirations predicted identity aspirations 11 years later. We also found that, while prior successful entrepreneurial experiences positively influenced current identity aspirations, unsuccessful experiences did not decrease them. It is noteworthy that these results hold even when considering working for others in new business projects as an (indirect) entrepreneurial experience. Our study contributes to the literature by extending the scarce longitudinal evidence that supports the temporal stability of entrepreneurial identity and by adding novel evidence regarding the mediating impact of real-life entrepreneurial experiences while considering both their direct and indirect nature and their positive and negative outcomes. This study may be relevant to policymakers and entrepreneurship educators by providing evidence of a virtuous cycle between entrepreneurial identity and action and its boundary conditions. [ABSTRACT FROM AUTHOR]

Indian Blackbuck's social system is fluid and composed of distinct groups. Information on age-sex association, temporal stability, and socio-ecological correlates are scarce. For establishing a baseline information on these, we studied the Blackbuck population at Point Calimere Wildlife Sanctuary, southern India, aimed at understanding the (i) social structure, (ii) association patterns, temporal stability and (iii) socio-ecological correlates related to predation, season, and anthropogenic covariates. Focal herds were observed following scan sampling during 2017-2019. Female herds and territorial pseudo-harems spread tightly, while mixed herds were spread in different degrees. Bachelor herds were loose or scattered with small herds. Dyadic associations of female herds were stronger and more stable than mixed-sex herds and pseudo-harems, but males were in flux. Both grasslands and habitat openness were associated with higher levels of female sociality, indicating their importance in foraging, sociality, and predator vigilance, to which proliferating invasive Prosopis juliflora poses a detrimental effect. The presense of sympatric invasive species and lower level of anthropogenic activity was another significant covariate that influenced resource choice grouping, fission-fusion, and ultimately association dynamics. To help answer broader questions about the blackbuck's sociality, and its socio-ecological environment that drive its association patterns, we present here some baseline data on the species from a coastal forest. We suggest control of invasive species and more detailed societal studies to arrive at conservation and management clues through understanding evolutionary and ecological basis of sociability of the antelope species. [ABSTRACT FROM AUTHOR]

Nitrogen (N) enrichment threatens the ability of grasslands to support sustainable functions. However, we do not know whether grassland degradation can alter the effect of N enrichment on the multidimensional stability of plant community productivity.Using data from N enrichment experiments at temperate grassland sites (no, moderate and severe degradation) that experienced a flooding event, we tested the impact of N enrichment on multidimensional stability (resistance, resilience, recovery and temporal stability) of plant community productivity.In non‐degraded and moderately degraded grasslands, N enrichment negatively influenced resistance and temporal stability but positively altered resilience and did not change recovery. Species asynchrony altered all stability dimensions, except for recovery. In severely degraded grasslands, the effects of N enrichment on multidimensional stability shifted. Resilience and recovery were negatively affected by N enrichment, while resistance and temporal stability were not influenced. A decrease in dominant species stability reduced community resilience and recovery in severely degraded grasslands.Synthesis and application. Grassland degradation regulates the effect of N enrichment on the multidimensional stability of plant community productivity. Thus, our findings highlight the need to consider grassland degradation in future studies for a comprehensive understanding of grassland dynamics. [ABSTRACT FROM AUTHOR]

There is mounting evidence from experimental studies that drought and nutrient enrichment can interact to impact the biodiversity and productivity of terrestrial ecosystems. Whether such interactive effect influences plant diversity and the temporal stability of community productivity of natural ecosystems is unknown. To fill this knowledge gap, we combined a field survey of plant diversity and soil conditions with remote sensing temporal estimates of primary productivity in grasslands along a natural gradient in northern China. We found that aridity and soil ammonium (NH4+‐N) interacted to influence temporal stability of NDVI. That is, the relationship between ammonium and temporal stability of NDVI shifted from positive to negative due to increased standard deviation of NDVI with increasing aridity. Species richness was not related to temporal stability because it influenced the mean and standard deviation of NDVI proportionally. As a result, soil fertility outweighed the contribution of species richness to temporal stability. Our study demonstrates the synergistic effect of aridity and soil fertility, but not species richness, on temporal stability along a large natural gradient. Predicting how environmental drivers affect diversity and the stable provisioning of ecosystem services in real‐world ecosystems therefore requires a better understanding of the complex interactions among environmental drivers. [ABSTRACT FROM AUTHOR]

Roundabout crashes are common worldwide but have received little attention. In particular, the investigation remains relatively understudied in distinct collision modes of roundabout crashes, including angle and non-angle crashes. This study investigates differences in factors affecting injury severity between angle and non-angle crashes and how these differences change over time. Random parameter logit models with heterogeneity in mean and variance were estimated using 2012–2019 Florida crash data. Variables considered for the modeling include temporal characteristics, environmental characteristics, road characteristics, spatial characteristics, vehicle characteristics, crash characteristics, and human characteristics. In addition, likelihood ratio tests were used to investigate the temporal instabilities of the models and differences in collision modes. The results showed that only a few variables demonstrated temporally stable effects for angle collisions (weekend and dark-lighted) and non-angle collisions (paved shoulders and cyclists), respectively. Unique influencing factors of injury severity were identified for different collision modes, such as dark-lighted, straight alignment, merge, lane departure, the disabled driver for angle collisions, and clear, fog, commercial vehicles, and aggressive driving for non-angle collisions. The results of the out-of-sample prediction simulations further demonstrate the difference in injury severity over time for angle and non-angle collisions. Overall results suggest that countermeasures can be implemented to reduce the injury severity of angle crashes/non-angle crashes based on the significant variables identified. This study may be used to improve roundabout safety by considering different collision modes. [ABSTRACT FROM AUTHOR]

The Chinese Loess Plateau has undertaken a large-scale "Grain for Green" project since 1999. Understanding how reforestation affects soil moisture is crucial for ecological construction and the region's revegetation. In this study, soil sensors were installed to monitor the soil moisture content (SMC) and soil desiccation intensity in a 0–200 cm soil profile online during the growing season, with farmland as a control and Robinia (R.) pseudoacacia L., Pinus (P.) tabulaeformis Carr., Populus (P.) alba L., and Ulmus (U.) pumila L. were selected. The results showed that the SMC increased with soil depth, and the soil moisture storage (SMS) in the 0–200 cm soil profile was ranked as R. pseudoacacia L. (424.3 mm) < farmland (479.8 mm) < U. pumila L. (569.8 mm) < P. alba L. (583.9 mm) < P. tabulaeformis Carr. (589.8 mm). Secondly, the percentages of inefficient water and gravimetric water in soil moisture were ranked as R. pseudoacacia L. (63%) > farmland (49%) > U. pumila L. (43%) > P. alba L. (17%) > P. tabulaeformis Carr. (11%). The soil desiccation intensity of artificial forests was heavy in June, light in April and July, and no desiccation in the other months. Moderate desiccation was discovered in the 0–40 cm soil layer and mild desiccation occurred in the 40–60 cm soil layer. Additionally, the representative soil layer for SMS in farmland for P. tabulaeformis Carr., U. pumila L., and R. pseudoacacia L. was the 90 cm soil layer, and the SMS representative soil layer for P. alba L. was the 70 cm soil layer. In brief, an SMS deficit occurred after the conversion of the farmland to R. pseudoacacia L., but there was an SMS surplus after the conversion of the farmland to P. alba L., U. pumila L., and P. tabulaeformis Carr. This suggests that the artificial forest species could be optimized by introducing P. tabulaeformis Carr. instead of R. pseudoacacia L., and the degradation of R. pseudoacacia L. could be suppressed by the application of a nitrogen fertilizer. Our research demonstrated that soil moisture depletion patterns were closely related to artificial forest species, and attention should be paid to the vegetation restoration and maintenance of afforestation achievements in water-constrained arid regions in the future. [ABSTRACT FROM AUTHOR]

Distraction and overspeed behaviors are acknowledged as two significant contributors to single-vehicle motorcycle crashes, injuries and fatalities resulting from which are severe and critical issues in Pakistan. To explore the temporal instability and differences in the factors determining the injury severities between single-vehicle motorcycle crashes caused by distraction and overspeed behaviors, this study estimated two groups of random parameter logit models with heterogeneity in means and variances. Single-vehicle motorcycle crash data in Rawalpindi city between 2017 and 2019 was used for model estimation, and a wide variety of explanatory variables relating to the rider, roadways, environments, and temporal attributes was simulated in the models. The current study considered three possible crash injury severity outcomes: minor injury, severe injury and fatal injury. Likelihood ratio tests were conducted to explore the temporal instability and non-transferability. Marginal effects were also calculated to further reveal temporal instability of the variables. Except for several variables, the most significant factors reported temporal instability and non-transferability, manifested as the effects varied from year to year and across different crashes. Moreover, out-of-sample prediction was also implemented to capture temporal instability and non-transferability between distraction and overspeed crash observations. The non-transferability between motorcycle crashes caused by distraction and overspeed behaviors provides insights into developing differentiated countermeasures and policies targeted at preventing and mitigating single-vehicle motorcycle crashes caused by the two risk-taking behaviors. [ABSTRACT FROM AUTHOR]

One of the most crucial aspects of 3D facial models is facial reconstruction. However, it is unclear if face shape distortion is caused by identity or expression when the 3D morphable model (3DMM) is fitted into largely expressive faces. In order to overcome the problem, we introduce neural networks to reconstruct stable and precise faces in time. The reconstruction network extracts the 3DMM parameters from video sequences to represent 3D faces in time. Meanwhile, our displacement networks learn the changes in facial landmarks. In particular, the networks learn changes caused by facial identity, facial expression, and temporal cues, respectively. The proposed facial alignment network exhibits reliable and precise performance in reconstructing static and dynamic faces by leveraging these displacement networks. The 300 Videos in the Wild (300VW) dataset is utilized for qualitative and quantitative evaluations to confirm the effectiveness of our method. The results demonstrate the considerable advantages of our method in reconstructing 3D faces from video sequences. [ABSTRACT FROM AUTHOR]

Climate warming and extreme climatic events are threatening ecosystem processes and functions. However, it remains unclear how climate warming changes ecosystem stability in facing extreme rainfall events.Here, we investigated the temporal stability of above‐ground net primary productivity (ANPP) in an alpine meadow via a 5‐year warming experiment, during which two flooding events occurred, in an alpine meadow.We first found that warming significantly increased the temporal stability of ANPP in facing flooding events by increasing resistance to and decreasing recovery from flooding events. Second, we found that warming shifted the plant community structure by increasing the dominance of grasses and reducing species richness and asynchrony. Last, we detected the higher temporal stability of ANPP under warming, which was mainly ascribed to the warming‐induced increase in dominant species stability (Deschampsia caespitosa).Synthesis. These findings indicate that climate warming may mitigate the shock of flooding events on the temporal stability of community productivity via altering plant community structure in alpine grasslands. Our study highlights that to buffer ecosystems from climatic extremes, we should focus on promoting the maintenance or selection of dominant species rather than only focusing on increasing species richness. [ABSTRACT FROM AUTHOR]

Retrieving information from memory, compared with different control conditions, improves subsequent retention of that information. Given the ubiquitous demonstration of this retrieval practice effect, researchers have asked whether such benefit is moderated by individual-difference variables. An implicit assumption in individual-difference research is that the retrieval practice effect at the participant level is reliable across participants. In this study, we tested this reliability assumption. In two sessions, 54 participants studied foreign–native word pairs, repeatedly restudied half of the word pairs, repeatedly retrieval-practised the other half, and, finally, took a final test for all pairs. Different word pairs were used in each session. We replicated the retrieval practice effect at the group level in Sessions 1 (d = 0.54, 95% confidence interval [CI] = [0.27, 0.80]) and 2 (d = 0.79 [0.53, 1.05]). In addition, we found that the retrieval practice effect at the participant level was reliable over a 1-week span both for absolute agreement, intraclass correlation coefficient (ICC) =.33 [.12,.51], and for consistency estimates, ICC =.35 [.14,.53]. The result bridges a gap in the literature of individual differences on the retrieval practice effect. We suggest that future studies identify whether, and under which experimental conditions, the retrieval practice effect at the participant level may show even greater reliability estimates than the ones reported here. The finding may also pave the way for studies assessing whether the magnitude of the retrieval practice effect is domain-general or paradigm-specific. [ABSTRACT FROM AUTHOR]

Key message: We found that the stabilizing mechanisms for forest productivity varied across harvesting intensities in a mixed broad-leaved Korean pine forest. Effects of overyielding at high species richness and species asynchrony occurred only in unharvested and lightly harvested plots, whereas asymmetries between individuals of different size contributed significantly to stabilizing productivity when harvestings became intensive. Context: Understanding the driving factors of forest ecosystem stability has become increasingly crucial in forest management. However, it remains unclear whether and how the stabilizing mechanisms of forest productivity might be influenced by management practices. Aims: We related the temporal stability of aboveground biomass productivity to harvesting history. We further tested how three key driving mechanisms of stability might be modulated by selective harvesting intensities. Methods: Based on a 10-year monitoring (five repeated tree inventories) of a mixed broad-leaved Korean pine forest in Northeastern China recovering from selective harvesting, we examined the relative importance of two diversity-dependent mechanisms (overyielding and species asynchrony) and one size-dependent mechanism (asymmetric growth) for productivity stability across a wide range of intensities (0–73.4% basal area removed). Results: We found that selective harvesting significantly lowered the productivity stability, species asynchrony, and growth dominance coefficient. Growth dominance coefficient had an overall stronger effect on stability than species richness and asynchrony. Moreover, the strengths of stabilizing mechanisms varied across harvesting intensities: effects of overyielding at high species richness and species asynchrony were detected only in unharvested and lightly harvested plots, whereas the explanatory power of growth dominance coefficient outweighed the diversity-related variables when harvesting became intensive. Conclusions: We emphasized the importance to consider both diversity- and size-related explanatory variables as potential mechanisms for the temporal stability of forest productivity. In fact, how growth is partitioned among trees of different species as well as sizes may co-determine the response of forest stability to disturbances. [ABSTRACT FROM AUTHOR]

In order to enhance food security and promote sustainable agricultural development, there is extensive utilization of sloping land in China. However, soil and water loss are severe in sloping lands. Understanding the spatiotemporal variability of soil water content (θ) is therefore important for determining suitable soil and water conservation strategies. Nevertheless, there exists a dearth of current research that focuses on the spatiotemporal variability of θ in microscale sloping lands. This study used statistical and temporal stability (TS) analyses to explore the characteristics of the spatiotemporal variability of θ on slopes. Furthermore, this study aimed to quantify the impacts of soil depth, slope position, air temperature, and hydrological conditions on the TS of θ. The average θ increases with depth, and it follows a logarithmic increase above 1.3 m and a linear increase below 1.3 m. The spatial variability of θ is higher in shallow soils and wet seasons compared with deep soils and dry seasons. The temporal stability of θ is higher on the upper and lower slopes compared with the middle slope. Day-MRD is more effective at capturing the temporal stability of θ than all-MRD. The diurnal variation of the TS of θ on slopes is primarily influenced by soil depth, slope position, air temperature, and hydrological conditions. We found that soil depth had a greater impact on the TS of θ than the slope position and that air temperature has a greater influence than the hydrological conditions. This study accurately describes the spatiotemporal variability of θ at the microscale slope, which helps solve the problems of soil and water conservation and water resource management on slopes. [ABSTRACT FROM AUTHOR]

Environmental change is a crucial driver shaping grassland biodiversity and stability. Both environmental change and stability contain multiple dimensions. Nonetheless, few studies examined multiple dimensions of stability in response to environmental change, especially under the combined effects of climatic variability and grazing intensity. Here, we conducted a 7-year field sheep grazing experiment, and we evaluated the impacts of grazing intensity (GI) and climate variability (temperature and precipitation variability) on plant community diversity and productivity and multi-dimensional stability using linear and structural equation models. Our results show that increasing grazing intensity significantly decreased temporal stability but did not affect resistance stability. Compared with the non-grazing (NG) treatment, grazing reduced temporal stability by 35.78%. The decline is primarily attributed to the grazing-induced reduction in evenness and weakening of species asynchrony, which in turn impairs insurance effects. The insignificant change in resistance stability was attributed to a trade-off between reduced interspecific competition and direct negative effects. Furthermore, temperature variability and precipitation variability exacerbate and mitigate the effects of grazing on temporal stability (negative) and resistance stability (positive), respectively. Overall, temporal stability is mainly influenced by temperature variability and GI, while resistance stability is mainly affected by GI. Our findings highlight the importance of considering the dimensions of stability and disturbance. Different dimensions of stability may respond differently to disturbance. Multiple disturbances may also interact synergistically or antagonistically on plant community stability. [ABSTRACT FROM AUTHOR]

Soil moisture has a great influence on vegetation growth and survival in arid and semiarid regions. Information about deep soil moisture dynamics is vital for restoring vegetation and improving land management on the water-limited Loess Plateau. The spatiotemporal dynamics and temporal stability of deep soil moisture (at a soil depth of 600 cm) were observed in situ under Caragana korshinskii shrubs that had various stand ages (named CK-10yr, CK-20yr and CK-35yr) in the Loess hilly region of China. The results showed that under C. korshinskii, soil moisture generally decreased as the stand age rose. Meanwhile, its moisture was consistent with precipitation variation, and an obvious time lag in soil moisture was found compared to that in precipitation during the entire growing season. Along the soil profile, a transition belt linking the shallow with deep soil moisture occurred at a 200 cm soil depth in different slope positions and aspects. At the slope scale, both the slope aspect and slope position significantly affected soil moisture variation in the areas with planted C. korshinskii shrubs, experiencing a decreasing trend from semi-shady slopes to sunny ones and from lower positions to upper ones. However, the variance in soil moisture between different positions and slope aspects was small. For the slope aspect, except for CK-20yr, the different-aged C. korshinskii shrubs had higher soil moisture content on sunny slopes than on semi-shady slopes at the upper 0–200 cm soil depth, while the opposite was true at the 200–600 cm soil depths. For slope positions, the soil moisture variation was small between the 0 and 200 cm soil depths and larger between the 200 and 600 cm soil depths. Within the whole profiles, the representative depth under the C. korshinskii shrubs for the soil moisture content was mainly concentrated between the 400–500 cm soil depths, on average, showing a gradual deepening trend with increasing restoration age. In summary, the findings indicate that natural recovery with low-water consumption grasslands and manual management measures, such as thinning and mowing, should be strengthened to minimize the high soil moisture consumption rates that occur in a healthy soil moisture environment and maintain sustainable vegetation restoration. [ABSTRACT FROM AUTHOR]

Understanding the effects of diversity on ecosystem stability in the context of global change has become an important goal of recent ecological research. However, the effects of diversity at multiple scales and trophic levels on ecosystem stability across environmental gradients remain unclear. Here, we conducted a field survey of α‐, β‐, and γ‐diversity of plants and soil biota (bacteria, fungi, and nematodes) and estimated the temporal ecosystem stability of normalized difference vegetation index (NDVI) in 132 plots on the Mongolian Plateau. After climate and soil environmental variables were controlled for, both the α‐ and β‐diversity of plants and soil biota (mainly via nematodes) together with precipitation explained most variation in ecosystem stability. These findings evidence that the diversity of both soil biota and plants contributes to ecosystem stability. Model predictions of the future effects of global changes on terrestrial ecosystem stability will require field observations of diversity of both plants and soil biota. [ABSTRACT FROM AUTHOR]

Research on the concentration and stability of crime patterns at microplaces primarily examines years as the temporal unit of observation. This study examines temporal patterns between months to explore the impact of the modifiable temporal unit problem (MTUP). We analyzed 26,555 violent crime incidents reported to the St. Louis Metropolitan Police Department from a 60-month observation period and geocoded these incidents to 14,106 street segments. Street segments with crime experienced these incidents across a small number of months and there is much variability in which locations are hot spots between months. Only a small number of street segments experienced a seasonal pattern between months with most locations having complete instability or unpredictability in the months when crime does occur. [ABSTRACT FROM AUTHOR]

Citizens' attitudes towards and their perceptions of climate change are widely believed to influence citizens' actions related to climate change. Knowledge of these attitudes and willingness to pay (WTP) for environmental improvement can be useful in designing an environmental policy. Although citizens' attitudes and perceptions are likely to affect their WTP, they are rarely included in the non-market valuation. Furthermore, over time, attitudes and perceptions of environmental issues are likely to change. An understanding of temporal stability of attitudes towards climate change could shed the light on changes in citizens' WTP for environmental quality over time. This study examined changes in perceptions, attitudes, and actions towards climate change using two surveys in Queensland, Australia. The surveys were administered 10 years apart (2009 and 2018). The effect of attitudes over time on WTP was analysed using a contingent valuation (CV) method. The results confirmed that attitudes and perceptions of climate change were important factors affecting actions of respondents. Furthermore, over time, some attitudes and perceptions changed significantly. However, only some attitudes and perceptions were significant predictors of consumers' WTP for a change in environmental quality. [ABSTRACT FROM AUTHOR]

Our planet is facing a variety of serious threats from climate change that are unfolding unevenly across the globe. Uncovering the spatial patterns of ecosystem stability is important for predicting the responses of ecological processes and biodiversity patterns to climate change. However, the understanding of the latitudinal pattern of ecosystem stability across scales and of the underlying ecological drivers is still very limited. Accordingly, this study examines the latitudinal patterns of ecosystem stability at the local and regional spatial scale using a natural assembly of forest metacommunities that are distributed over a large temperate forest region, considering a range of potential environmental drivers. We found that the stability of regional communities (regional stability) and asynchronous dynamics among local communities (spatial asynchrony) both decreased with increasing latitude, whereas the stability of local communities (local stability) did not. We tested a series of hypotheses that potentially drive the spatial patterns of ecosystem stability, and found that although the ecological drivers of biodiversity, climatic history, resource conditions, climatic stability, and environmental heterogeneity varied with latitude, latitudinal patterns of ecosystem stability at multiple scales were affected by biodiversity and environmental heterogeneity. In particular, α diversity is positively associated with local stability, while β diversity is positively associated with spatial asynchrony, although both relationships are weak. Our study provides the first evidence that latitudinal patterns of the temporal stability of naturally assembled forest metacommunities across scales are driven by biodiversity and environmental heterogeneity. Our findings suggest that the preservation of plant biodiversity within and between forest communities and the maintenance of heterogeneous landscapes can be crucial to buffer forest ecosystems at higher latitudes from the faster and more intense negative impacts of climate change in the future. [ABSTRACT FROM AUTHOR]

Background: Radiochromic silicone-based dosimeters are flexible 3D dosimeters, which at appropriate concentration of leucomalachite green (LMG) and curing agent are dose-rate independent for clinical photon beams. However, their dose response is based on chemical processes that can be influenced by temporal and thermal conditions, impacting measurement stability. Purpose: The aim of this study was to investigate the temporal stability of the dose response of radiochromic dosimeters for different curing times and postirradiation storage temperatures. Methods:Six cylindrical dosimeters (5 cm diameter,5 cm length) were produced in a single batch and separated into two groups that were irradiated 72 and 118 h after production. The same photon plan, consisting of two 10 × 1.6 cm2 opposing fields, was delivered to all dosimeters. After irradiation,the dosimeters were separated into three groups, stored at 5◦C, 15◦C, and 20◦C, and read out for five consecutive days. Results: Storage temperature influenced the measurement stability, and changes in the optical response with time differed between irradiated and nonirradiated parts of the dosimeters. The relative change between signal and background was greater than 10% for all measurements performed 24 h or more after irradiation, except for dosimeters stored at 5◦C, which changed by 2%–5% after 24 h.The dosimeter temporal stability was not influenced by curing time. Conclusions: For room temperature storage (15◦C and 20◦C), readout should take place as soon as possible after irradiation since the background color increased rapidly for both curing times (72 and 118 h), whereas the dosimeters are stored at 5◦C, readout can be performed up to 24 h after. [ABSTRACT FROM AUTHOR]

The role of silver–silver chloride electrode for providing the reference potential is quite important for the precise potentiometric measurements. Our study focuses to find the conditions for its optimal use, especially, in perspective for a long-term viability of electrode. In particular, we reassessed the temporal stability of the standard potential and presented the results of its measurement for a time span of ten years. [ABSTRACT FROM AUTHOR]