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Temporal trends in the size composition (length frequency) and length–weight (L–W) relationship of chokka squid Loligo reynaudii on the south coast of South Africa were assessed over periods spanning 22 years: length frequencies from 1996 to 2017 (with 15 years represented); and L–W relationships over 9 years between 1994 and 2016. To allow for comparison, identical data selection and processing was adopted for all years considered (i.e. identical period of 60 days in spring–summer; the same depths and areas; chokka with empty stomachs; and squid of the same maturity stage). Although there were no significant long-term temporal trends in the mean lengths, there was a significant short-term drop in the mean lengths over the years 2014–2017 (especially in females), which could not be attributed with certainty to any cause. A tentative explanation is that this drop might be linked to the introduction of an additional closed season in these years. The estimated parameters of the L–W relationship also revealed no trend over the years considered. Investigation of the caecum colour, which indicates the state of starvation (white: 8 h on average after food ingestion; yellow: 6 to 7 h after food ingestion), showed significantly more starving males than starving females. Starvation of males on the spawning grounds might be associated with the spawning behaviour of chokka.

Background One of the most critical issues in human-computer interaction applications is recognizing human emotions based on speech. In recent years, the challenging problem of cross-corpus speech emotion recognition (SER) has generated extensive research. Nevertheless, the domain discrepancy between training data and testing data remains a major challenge to achieving improved system performance. Methods This paper introduces a novel multi-scale discrepancy adversarial (MSDA) network for conducting multiple timescales domain adaptation for cross-corpus SER, i. e., integrating domain discriminators of hierarchical levels into the emotion recognition framework to mitigate the gap between the source and target domains. Specifically, we extract two kinds of speech features, i.e., handcraft features and deep features, from three timescales of global, local, and hybrid levels. In each timescale, the domain discriminator and the emotion classifier compete against each other to learn features that minimize the discrepancy between the two domains by fooling the discriminator. Results Extensive experiments on cross-corpus and cross-language SER were conducted on a combination dataset that combines one Chinese dataset and two English datasets commonly used in SER. The MSDA is affected by the strong discriminate power provided by the adversarial process, where three discriminators are working in tandem with an emotion classifier. Accordingly, the MSDA achieves the best performance over all other baseline methods. Conclusions The proposed architecture was tested on a combination of one Chinese and two English datasets. The experimental results demonstrate the superiority of our powerful discriminative model for solving cross-corpus SER.

Otolith shape analysis provides a robust tool for the discrimination of many fish stocks in the context of fisheries management. However, there has been little research to examine within-stock temporal stability of otolith morphology in relation to changes in the environment and stock conditions. This study investigated the variability of Northeast Arctic (NEA) cod (Gadus morhua) otolith shape between 1933 and 2015, using elliptical Fourier descriptors extracted from archived material of 2968 mature fish. Series of hierarchical multivariate models were developed to relate shape to the identified optimal windows of some environmental drivers. Differences between years accounted for

The chief goal of the present study was to elucidate whether the short-term temporal relationships between depressive and anxious symptoms vary by sex. Three hundred and fifty-seven undergraduate students self-reported depressive and anxious symptomatology with the Beck Depression Inventory (BDI-II) and the Beck Anxiety Index (BAI) two times 11 weeks apart. A latent variable path model analysis found support for a bi-directional relationship between depressive symptoms and anxious symptoms for the overall sample. An equality constraint analysis revealed that depressive symptoms predicted anxious symptoms over time to a similar extent as anxious symptoms predicted depressive symptoms over time. However, several temporal relationships significantly varied by sex, namely, females demonstrated greater stability of depressive symptoms over time, and evidenced a stronger cross-lag relationship from depressive symptoms at Time 1 to anxious symptoms at Time 2, and males, on the other hand, exhibited a marginally more stable anxious symptoms test-retest relationship over time. The results supported the existence of a bi-directional relationship between depressive and anxious symptoms over a short-term period of time for emerging adults. We conclude that current states of depressive symptoms may be more influential for females’ subsequent negative affective states, whereas anxious symptoms may be more important for males’ subsequent negative affective states.

This paper addresses the Multi-Athlete Tracking (MAT) problem, which plays a crucial role in sports video analysis. There exist specific challenges in MAT, e.g., athletes share a high similarity in appearance and frequently occlude with each other, making existing approaches not applicable for this task. To address this problem, we propose a novel online multiple athlete tracking approach which make use of long-term temporal pose dynamics for better distinguishing different athletes. Firstly, we design a Pose-based Triple Stream Network (PTSN) based on Long Short-Term Memory (LSTM) networks, capable of modeling long-term temporal pose dynamics of athletes, including pose-based appearance, motion and athletes&rsquo, interaction clues. Secondly, we propose a multi-state online matching algorithm based on bipartite graph matching and similarity scores produced by PTSN. It is robust to noisy detections and occlusions due to the reliable transitions of multiple detection states. We evaluate our method on the APIDIS, NCAA Basketball and VolleyTrack databases, and the experiment results demonstrate its effectiveness.

Background and aimThe reciprocal relation between falling and concern about falling is complex and not well understood. We aimed to determine whether concern about falling increases after a fall and whether concern about falling increases the odds of future falls in community-dwelling older adults without a recent fall history.MethodsWe selected 118 community-dwelling older adults (mean age: 71.4 (SD: 5.3) years) without a self-reported history of falling, one year prior to baseline assessment, from the one-year VIBE cohort for analyses. On a monthly basis, we recorded concern about falling (using the Falls Efficacy Scale-International, FES-I), as well as the occurrence of falls (through questionnaires and telephone calls). We determined 1) whether falling predicts an increase in concern about falling and 2) whether a high concern about falling is predictive of falling. Standard linear (fixed-effects) regression and mixed effects regression analyses were performed over long-term, i.e. one year, and short-term, i.e. one-month, intervals, respectively and were adjusted for gender, age and physical activity (quantified as the average total walking duration per day). Analyses were performed separately for all reported falls and for injurious falls only.ResultsHigh concern about falling at baseline did not predict falls over the course of one year, nor over the course of one month. Furthermore, falls in between baseline assessment and one year thereafter did not predict increased concern about falling from baseline to one year later, independent of whether all falls or only injurious falls were considered. However, falls, either all or injurious only, happening somewhere over the course of a one-month interval, significantly predicted small increases in concern about falling (1.49 FES-I points, 95% CI [0.74, 2.25], pConclusionOlder adults without a recent history of falling seem to be resilient against developing concern about falling after having fallen, resulting in a short-term temporary effect of falling on concern about falling. Furthermore, we found no evidence that a high concern about falling predicts future falls over a one-month or a one-year follow-up period, suggesting that concern is not a primary cause for falls in older adults without a recent history of falling.

In order to investigate the effect of wave processes on the geotechnical characteristics of topmost sediments, a Portable Free Fall Penetrometer (PFFP) was deployed in the energetic nearshore zone of the U.S. Army Corps of Engineers' Field Research Facility (FRF) in Duck, NC. A total of 335 deployments were conducted from the FRF's 560 m long pier over six non-consecutive days in September and October of 2016. During the surveying period, significant wave heights varied between Hs = 0.8–2.4 m measured at a water depth of 17.4 m. The results showed that the sediment strength is affected by the wave climate. The derived average maximum quasi-static bearing capacities (qsbc), which reflects sediment strength, during low energy wave periods (September 22–24 and 26; Hs = 0.8–1.3 m) ranged between 67 and 73 kPa with maximum qsbc values of 120–136 kPa, while the average values were 47–59 kPa with a maximum qsbc of 82–98 kPa during the high energy wave periods (October 5–6; Hs = 2.4 m). Results also showed that the sediment strength decreased in the shallow water depth regions in spite of the increase in the particle size distribution, due to the increasing wave impact on the seabed within the shallow water region. The area where seabed strength variations were affected by the wave action became wider in the cross-shore direction as the wave height increased. Results further showed that the strength of the topmost sediment layers varied spatially along the profile and temporarily with variations in significant wave height. This likely reflects the impact of waves on sediment strength.

Purpose This study aims to capture the effective behavior of double-diffusion problem, which arises from the combined heat and mass transfer in porous medium and develop the modified characteristics finite element method. Design/methodology/approach The proposed finite element method deals with the nonlinear term temporal term by modified characteristics method. Then, the authors compute the velocity, pressure, temperature and concentration using the decoupled technique. Finally, to show the efficiency of the method, the authors give some numerical examples. Findings From the numerical results, one can see that the method has a good accuracy, which shows that the method can simulate this Darcy–Brinkman problem well. Originality/value The originality lies in the fact that the proposed scheme is the first time for solving the Darcy–Brinkman problem, which is a more complicated model, and includes the velocity, pressure, temperature and concentration.

Land cover and historical land use practices are the leading drivers of the hydrological response in most catchments systems. Timing, periodicity and magnitude of precipitation-discharge feedbacks are thus impacted by such site-specific characteristics. We analysed the long-term precipitation and discharge databases of four experimental catchments located in the Central Spanish Pyrenees and thus similar in their climate. Furthermore, they have a gradient of land cover (from a relatively pristine forested catchment, through an abandoned cultivated catchment with progressive plant recolonization, to an afforested catchment and ending by a bare degraded badland catchment); so, form a solid benchmark to assess such dynamic changes. For the analysis of the long-term precipitation and discharge time-series we use the wavelet transform methodology, which proves valuable to segregate the continuous hydrological response of the catchments in different and non-similar dominant time-scales. Precipitation and discharge events are not just identified and analysed in terms of magnitude or correlation relationships but also the time-localization of each transient precipitation and discharge events is retrieved. We thus no impose any fixed periodicity in the occurrence of hydrological events and ultimately, we are able to infer the real and site-specific temporal variability of each dataset through which we can infer the timing, variability and physical mechanisms of water storage/transport in each catchment. Thereby, this analysis reveals the land-cover-discharge feedbacks that takes place at different time-scales.

Agroecological schemes are implemented worldwide in order to reduce water quality impairment from agricultural pesticide use. However, evaluating the success or failure of these schemes is challenging because other influencing factors can confound their effects. For instance, aquatic pesticide pollution has been found to vary greatly due to the interannual variability in weather conditions (e.g., the timing, intensity, and duration of precipitation events) and changes in pesticide application practices (e.g., changing pest pressure, phasing-out and replacement of specific products, development of pesticide resistance).Our research investigates the necessary conditions to detect significant trends in pesticide concentrations in the context of the Swiss National Action Plan (NAP), which aims to halve aquatic pesticide pollution risk from agricultural pesticide use within Swiss river networks by 2027.We base our analyses for temporal trends on a calibrated model for pesticide transport at the catchment scale, which we use to separate the long-term effects of the NAP from interannual variability due to weather conditions. Our results indicate that the interannual variability due to weather conditions can override the effects of even a 50% reduction in pesticide application for rain-driven input. This implies that the concentration levels themselves may be insufficient to demonstrate the effectiveness of the NAP within a reasonable time horizon of a decade. This is because the lowering of in-stream pesticide concentrations can be due to the timing and intensity of precipitation relative to the application of pesticides and not from the effectiveness of pesticide mitigation measures. Therefore, we have further explored potential methods to account for the weather effects on the pesticide concentration levels. Accounting for the weather conditions by considering the dependence of concentration levels on discharge conditions during the application period improves the statistical power to detect trends.Furthermore, we assess the potential to extrapolate the trends observed at 23 monitoring sites from different catchments (varying in size 1 km2 to > 20,000 km2) across Switzerland to the entire Swiss river network. As a first step, we analyzed substances applied to corn because this crop is widespread in the country, is easy to follow as herbicides are applied only once a year, and only a few pesticides are applied. The analysis revealed that for some of these corn herbicides, the seasonal patterns were consistent across many catchments and in agreement with the crop specific expectations. However, for other herbicides we identified regional patterns with unexpected concentration peaks in the fall. This observation requires more detailed inquiries in regional use patterns and highlights the need to account for regionalized pesticide use when extrapolating monitoring data to larger scales.

In this chapter, we discuss the problems of the human now, that attracted much attention in the XX century, and a number of their comprehensive accounts proposed at the beginning of the XXI century. We combine these accounts under the term temporal experience or temporal consciousness and analyze them in detail. During this analysis, in parallel, we formulate some of the main premises making up the gist of our account of the human temporality and describe the basic elements of individual temporal dimension attributed to the mind. In particular, the following issues are discussed in detail: The structure of a single unit of temporal experience. How these units are combined into the stream of experiences and form the diachronic unit of temporal experience. The available experimental data elucidating the details and particular time scales characterizing the experiential now.

We compared long-term (1977 to 2014) trends in concentrations of PFAS in eggs of the marine sentinel species, the Northern gannet (Morus bassanus), from the Irish Sea (Ailsa Craig) and the North Sea (Bass Rock). Concentrations of eight perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonates (PFSAs) were determined and we report the first dataset on PFAS in UK seabirds before and after the PFOS ban. There were no significant differences in ∑PFAS or ∑PFSAs between both colonies. The ∑PFSAs dominated the PFAS profile (>80%); PFOS accounted for the majority of the PFSAs (98-99%). In contrast, ∑PFCAs concentrations were slightly but significantly higher in eggs from Ailsa Craig than in those from Bass Rock. The most abundant PFCAs were perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnA) which, together with PFOA, comprised around 90% of the ∑PFCAs. The ∑PFSAs and ∑PFCAs had very different temporal trends. ∑PFSAs concentrations in eggs from both colonies increased significantly in the earlier part of the study but later declined significantly, demonstrating the effectiveness of the phasing out of PFOS production in the 2000s. In contrast, ∑PFCAs concentrations in eggs were constant and low in the 1970s and 1980s, suggesting minimal environmental contamination, but residues subsequently increased significantly in both colonies until the end of the study. This increase appeared driven by rises in long chain compounds, namely the odd chain numbered PFTriDA and PFUnA. PFOA, had a very different temporal trend from the other dominant acids, with an earlier rise in concentrations followed by a decline in the last 15 years in Ailsa Craig; later temporal trends in Bass Rock eggs were unclear. Although eggs from both colonies contained relatively low concentrations of PFAS, the majority had PFOS residues that exceeded a suggested Predicted No Effect Concentration and ~ 10% of the eggs exceeded a suggested Lowest-Observable-Adverse-Effect., This work is part of the Predatory Bird Monitoring Scheme (PBMS) (http://pbms.ceh.ac.uk), which is supported by the Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability. The PBMS is additionally supported with funding from Natural England and the Campaign for Responsible Rodenticide Use (CRRU). We thank the licensed egg collectors who collected the eggs for the present study, Dr. Elba Garreta for carrying out chemical analysis and Dr. Peter Henrys for his advice on the statistical analyses. In Memoriam - Professor Richard Shore was a dedicated researcher who greatly contributed to wildlife science, and an esteemed colleague who will be deeply missed.

[ES] En el presente trabajo, se analizaron los cambios temporales en las curvas de duración de caudales CDC correspondientes a estaciones de caudales diarios en Colombia mediante la aplicación del test no paramétrico de Mann-Kendall, el Estimador de Pendiente de Sen y la pendiente de la regresión lineal de la serie. Se calculan caudales característicos con el fin de revisar tendencias a largo plazo entre distintas magnitudes o porcentajes de excedencia (percentiles 95, 75, 25 y 1). De forma adicional, se estima la tendencia en la desviación estándar en ventanas móviles de 10 años. Se observan tendencias crecientes significativas en las regiones del occidente (Chocó) y nordeste (Bajo cauca) de Colombia, mientras que para tendencias decrecientes no se observa ningún patrón espacial. Se encontraron tendencias con magnitudes entre –0.0068 m3/s/día y 0.047 m3/s/día., [EN] In this work, long term temporal changes are analyzed in several flow duration curves FDC from Colombian daily gauging stations by the mean of the application of non-parametric Mann-Kendall test, the Sen´s Slope Estimator and the slope of the linear regression of the time series. Characteristic flows were estimated aiming to analyze the existence of long-term trends in different flow magnitudes (percentiles corresponding to 95, 75, 25 and 1 percentage of exceedance). Additionally, standard deviation long term trend is estimated using a 10 years mobile window. Significant increasing trends are observed in the regions of Chocó (east) and Bajo Cauca (north-east) while decreasing trends did not present any particular spatial pattern. Long term trends magnitudes between –0.0068 m3/s/day and 0.047 m3/s/day were found., Los autores agradecen al Instituto de Hidrología Meteorología y Estudios Ambientales de Colombia IDEAM porque cuyos registros fueron parte fundamental de este análisis

This paper targets the SHL recognition challenge, which focuses on the location-independent and user-independent activity recognition using smartphone sensors. To address this long-range temporal problem with periodic nature, we propose a new approach (team IndRNN), an Independently Recurrent Neural Network (IndRNN) based long-term temporal activity recognition with spatial and frequency domain features. The data is first segmented into one second sliding windows, then temporal and frequency domain features are extracted as short-term temporal features. A deep IndRNN model is used to predict the unknown test dataset location. Under the predicted location, a deep IndRNN model is further used to classify the 8 activities with best performed features. Finally, transfer learning and model fusion are used to improve the result under the user-independence case. The proposed method achieves 86.94% accuracy on the validation set at the predicted location.

Traffic forecasting influences various intelligent transportation system (ITS) services and is of great significance for user experience as well as urban traffic control. It is challenging due to the fact that the road network contains complex and time-varying spatial-temporal dependencies. Recently, deep learning based methods have achieved promising results by adopting graph convolutional network (GCN) to extract the spatial correlations and recurrent neural network (RNN) to capture the temporal dependencies. However, the existing methods often construct the graph only based on road network connectivity, which limits the interaction between roads. In this work, we propose Geographic and Long term Temporal Graph Convolutional Recurrent Neural Network (GLT-GCRNN), a novel framework for traffic forecasting that learns the rich interactions between roads sharing similar geographic or longterm temporal patterns. Extensive experiments on a real-world traffic state dataset validate the effectiveness of our method by showing that GLT-GCRNN outperforms the state-of-the-art methods in terms of different metrics., 7 pages, 5 figures

Treatments on plantation forests, such as thinning, have a significant effect on the quality and quantity of water resources in the watersheds in Japan. However, few studies have performed intensive observations regarding the effects of thinning on the groundwater flow process with combined use of tracers, specially over a long period of time.In this study, stable isotope analysis and hydrological observations were applied to investigate the temporal variation of spring water and groundwater mean residence time in a small watershed at Mount Karasawa, Tochigi Prefecture, Japan. We have monitored the research area since 2010, with periodical sampling once a month for 9 years, with a lack of data in some years after the thinning. We analyzed the date for three different time periods, those are: Before Thinning, from July 2010 to September 2011, Soon After Thinning, from November 2011 to October 2013 and Long After Thinning, from September 2017 to August 2019.The mean residence time of spring water and groundwater were evaluated by using the stable isotopes of hydrogen and oxygen as tracers, then estimating their d-excess variations using two Lumped-Parameter Models, Exponential-Piston Flow Model and Dispersion Model. The SF6 concentrations were used as an Apparent Age analysis for determination of the model’s parameters. Both models show a tendency of the mean residence time getting older Soon After Thinning and then getting younger again Long After Thinning.According to a selection of the best model for this area, the Exponential-Piston Flow Model shows that the spring water mean residence time was 25 months Before Thinning, 30 months Soon After Thinning and 26 months Long After Thinning; the groundwater at 15m deep mean residence time was 39 months Before Thinning, 46 months Soon After Thinning and 38 months Long After Thinning and the groundwater at 30m deep mean residence time was 38 months Before Thinning, 47 months Soon After Thinning and 45 months Long After Thinning. These results suggest that Soon After Thinning there is a reduction of forest interception and tree evapotranspiration, leading to an increase in infiltration and groundwater storage. Then, Long After Thinning, the forest interception and tree evapotranspiration rise back again with the recovery of the understory vegetation, which leads to a decrease in infiltration and groundwater storage.

­­­Improved agricultural practices sequestering additional atmospheric C within the soil are considered as one of the potential solution for mitigating global climate change. However, agricultural used landscapes are complex and their capacity to sequester additional atmospheric C might differ substantially in time and space. Hence, accurate and precise information on the complex spatio-temporal CO2 flux pattern is needed to evaluate the effects/benefits of new agricultural practices aiming towards increasing soil organic carbon.To date, different approaches are used to measure and quantify CO2 flux dynamics of agricultural landscapes, such as e.g. eddy covariance, as well as manual and automatic chamber systems. However, all these methods fail to some extend in either accounting for small scale spatial heterogeneity (eddy covariance and automatic chambers) or short-term temporal variability (manual chambers). Although, automatic chambers are in principle capable to detect small-scale spatial differences of CO2 flux dynamics in a sufficient temporal resolution, these systems are usually limited to only a few spatial repetitions which is not sufficient to represent small scale soil heterogeneity such as present within the widespread hummocky ground moraine landscape of NE-Germany.To overcome these challenges, we developed a novel robotic chamber system allowing to detect small-scale spatial heterogeneity and short-term temporal variability of CO2 (as well as CH4 and N2O) flux dynamics for a range of different fertilization and tillage management practices. The system is equipped with two canopy chambers, CR6 data logger, CDM-A116 analog multiplexer and multiple sensors to measure plant activity/biomass development in parallel. The measurements of the gaseous C exchange is performed by moving the system along the tracks with each chamber along one half of the gantry crane. Thus, each chamber measures 18 plots, out of 36 plots (2x3m; 12 per soil type) established in the study area.Here, we present first CO2 flux measurement results (spring barley; 3 different soil types) using this novel system, to prove its overall accuracy and precision. Our results show clear small-scale/within field spatial pattern and short-term temporal dynamics regarding measured ecosystem respiration, net ecosystem exchange as well as derived gross primary productivity.

Objectives: To examine short-term associations between offending and victimization using daily data on criminal offenses. We also examine the within-individual association between several types of offenses and victimization and see whether incidents closer together in time are more likely reflect revenge motives. Method: We use total data on all victims ( n = 88,106) and offenders ( n = 60,584) in police-reported assaults in Finland during 2007–2009 to examine temporal clustering of the two outcomes. Monthly panel data ( n = 4,886) on offending and victimization are analyzed with fixed-effects regression models, while revenge motives are derived from detailed case descriptions ( n = 299). Results: The risk of violent victimization is higher in months following criminal offending. Although the offending rates directly before and after victimization are low on absolute terms, we find that these rates are higher around the time of victimization. Violent offenses closer to victimization incidents are more likely to include the same parties in opposite roles. Conclusions: Criminal offending increases the risk of victimization in a state-dependent matter. Closer analysis of situational and motivational dynamics of victimization and offending requires temporally detailed data, as a substantial share of the victim–offender overlap is explained by incidents that take place on the same day, complicating the analysis of the temporal sequence of those events.

Accurate estimates of cumulative N 2 O fluxes from agricultural soil are essential for quantifying global N 2 O emissions and for identifying effective mitigation strategies. This study focuses on the short term temporal variability of N 2 O fluxes, and on how the accuracy of annual cumulative estimates is affected by different (simulated) measuring frequencies of an automatic system based on the closed chamber method. Fluxes were measured with high temporal resolution (24 per day) for approximately one year on agricultural soil in the southwest of Sweden. The short-term temporal variability of N 2 O fluxes was considerable: the predictive power of measured fluxes decreased to negligible levels in a time frame of 4-5 h, and large intraday flux ranges were observed frequently, particularly in days with soil temperatures below 0 ∘ C. A time of day well suited for consistently providing good estimates of the mean daily flux could not be identified. Consequently, the accuracy of annual emission estimates strongly depended on the measuring frequency. Multiple measurements per day were necessary for consistently quantifying annual emission estimates with accuracy. Accuracy improved with measuring frequency increasing up to four times per day, and higher frequencies generated negligible further improvements. Based on this study the following recommendations are made with regard to measuring frequency: i) measure four times per day for maximum accuracy and ii) measure twice per day for a good compromise between accuracy and the number of plots that can be monitored.

Considering the potential importance of the concentration of ozone in the atmosphere and threat to its depletion in Pakistan’s environment, AQUA-AIRS Level-3 Daily Global satellite data is used to monitor the Total Column Ozone (TCO) over the entire region of the country. During 2003–2011 with spatial resolution of 1ox 1o lat/long grid, inter-annual analysis of TCO over the area (62°-76°E and 23°-37°N) showed that overall average distribution of TCO alterations are dependent on latitude and varied from 275 to 278 DU in the regions of Sindh and Baluchistan province with 297–300 DU in the northern and KPK province regions. Seasonal variations have shown that in the region 23°-29°N, highest concentration of ozone is recorded in summer season (JJA) and lowest in winter season (DJF) with mixed trend in both spring (MAM) and autumn (SON) seasons whereas in the region between 30°-37°N, maximum is recorded in winter (DJF) and spring (MAM) seasons with minimum in summer (JJA) and autumn (SON) seasons respectively. Statistical analysis revealed that linear relationship exists between year to year TCO and solar activity.

Normal aging is associated with a decline in memory and motor learning ability. However, the exact form of these impairments (e.g., the short-term temporal stability and affected learning mechanisms) is largely unknown. Here, we used a sensorimotor adaptation task to examine changes in the temporal stability of two forms of learning (explicit and implicit) because of normal aging. Healthy young subjects (age range, 19–28 years; 20 individuals) and older human subjects (age range, 63–85 years; 19 individuals) made reaching movements in response to altered visual feedback. On each trial, subjects turned a rotation dial to select an explicit aiming direction. Once selected, the display was removed and subjects moved the cursor from the start position to the target. After initial training with the rotational feedback perturbation, subjects completed a series of probe trials at different delay periods to systematically assess the short-term retention of learning. For both groups, the explicit aiming showed no significant decrease over 1.5 min. However, this was not the case for implicit learning; the decay pattern was markedly different between groups. Older subjects showed a linear decrease of the implicit component of adaptation over time, while young subjects showed an exponential decay over the same period (time constant, 25.61 s). Although older subjects adapted at a similar rate, these results suggest natural aging selectively impacts the short-term (seconds to minutes) temporal stability of implicit motor learning mechanisms. This understanding may provide a means to dissociate natural aging memory impairments from deficits caused by brain disorders that progress with aging.

Cognitive abilities enabling animals that feed on ephemeral but yearly renewable resources to infer when resources are available may have been favoured by natural selection, but the magnitude of the benefits brought by these abilities remains poorly known. Using computer simulations, we compared the efficiencies of three main types of foragers with different abilities to process temporal information, in spatially and/or temporally homogeneous or heterogeneous environments. One was endowed with a sampling memory, which stores recent experience about the availability of the different food types. The other two were endowed with a chronological or associative memory, which stores long-term temporal information about absolute times of these availabilities or delays between them, respectively. To determine the range of possible efficiencies, we also simulated a forager without temporal cognition but which simply targeted the closest and possibly empty food sources, and a perfectly prescient forager, able to know at any time which food source was effectively providing food. The sampling , associative and chronological foragers were far more efficient than the forager without temporal cognition in temporally predictable environments, and interestingly, their efficiencies increased with the level of temporal heterogeneity. The use of a long-term temporal memory results in a foraging efficiency up to 1.16 times better ( chronological memory) or 1.14 times worse ( associative memory) than the use of a simple sampling memory. Our results thus show that, for everyday foraging, a long-term temporal memory did not provide a clear benefit over a simple short-term memory that keeps track of the current resource availability. Long-term temporal memories may therefore have emerged in contexts where short-term temporal cognition is useless, i.e. when the anticipation of future environmental changes is strongly needed.

In a CPU cache utilizing least recently used (LRU) replacement, cache sets manage a buffer which orders all cache lines in the set from LRU to most recently used (MRU). When a cache line is brought into cache, it is placed at the MRU and the LRU line is evicted. When re-accessed, a line is promoted to the MRU position. LRU replacement provides a simple heuristic to predict the optimal cache line to evict. However, LRU utilizes only simple, short-term access patterns. In this paper, we propose a method that uses a buffer called the history queue to record longer-term access-eviction patterns than the LRU buffer can capture. Using this information, we make a simple modification to LRU insertion policy such that recently-recalled blocks have priority over others. As lines are evicted, their addresses are recorded in a FIFO history queue. Incoming lines that have recently been evicted and now recalled (those in the history queue at recall time) remain in the MRU for an extended period of time as non-recalled lines entering the cache thereafter are placed below the MRU. We show that the proposed LRU insertion prioritization increases performance in single-threaded and multi-threaded workloads in simulations with simple adjustments to baseline LRU.

OBJECTIVES To determine if temporal changes in dental fear over a 4-month period are predicted by changed cognitive vulnerability-related perceptions of going to the dentist. METHODS Australian adults (n = 484) completed mailed questionnaires at baseline and follow-up, containing measures of dental fear, cognitive vulnerability-related perceptions, dental services received, and possible aversive experiences during the study period. Change in dental fear was the main outcome measure, categorized as decreased (Fear- ), unchanged (Fear0 ), and increased (Fear+ ). RESULTS Across the study period, 15.5 percent of people had Fear- , 73.4 percent had Fear0 , and 11.1 percent had Fear+ . In a multinomial logistic regression, after controlling for participant gender, income, time since last dental visit at baseline, dental fear at baseline and experiencing an aversive event, increased vulnerability-related perceptions were significantly associated with Fear+ (OR = 2.83, P

Patient suffering of Major Depressive Disorder (MDD) often complain that subjective time seems to ‘drag’ with respect to physical time. This may point towards a generalized dysfunction of temporal processing in MDD. In the present study, we investigated temporal preparation in MDD. “Temporal preparation” refers to an increased readiness to act before an expected event; consequently, reaction time should be reduced. MDD patients and age-matched controls were required to make a saccadic eye movement between a central and an eccentric visual target after a variable duration preparatory period. We found that MDD patients produced a larger number of premature saccades, saccades initiated prior to the appearance of the expected stimulus. These saccades were not temporally controlled; instead, they seemed to reflect increased oculomotor impulsivity. In contrast, the latency of visually-guided saccades was strongly influenced by temporal preparation in controls; significantly less so, in MDD patients. This observed reduced temporal preparation in MDD was associated with a faster decay of short-term temporal memory. Moreover, in patients producing a lot of premature responses, temporal preparation to early imperative stimuli was increased. A reduction in premature saccades, however, was associated with reduced temporal preparation to late imperative stimuli.In conclusion, reduced temporal preparation and short-term temporal memory in the oculomotor domain supports the hypothesis that temporal processing was altered in MDD patients. These observed deficits could reflect other underlying aspects of abnormal time experience in MDD.

The comparability of data from active (ACT) and passive sampling (PAS) of persistent organic pollutants (POPs) in air is hindered by uncertainties related to the derivation of sampling rates and concentrations, as well as differences in the duration, volume and frequency of sampling. Although data from ACT have been used extensively in short-term PAS calibration studies, no attempts have been made to evaluate the comparability of long-term trends calculated from PAS to established ACT trends. This is crucial, as continuous long-term ACT is unfeasible in most regions of the world. To address these challenges, we calculated and compared trends for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) at the six sites in Europe with at least 5 years of co-located ACT and PAS data (2012–2016): Birkenes, Košetice, Pallas, Råö, Stórhöfði and Zeppelin. Strong agreement of ACT and PAS trends was observed for most OCPs and PCBs. Apart from two PCBs at Stórhöfði, all pairs of ACT and PAS trends followed the same direction. However, differences in the magnitude, significance and confidence intervals of their slopes were observed for some compounds and were primarily attributed to the short duration of the PAS time series. Despite some limitations, our results suggest that the comparability of ACT and PAS POP trends will continue to improve with additional years of data. This study confirms the suitability of PAS for the calculation of long-term POP trends in air, and highlights the importance of continuous sampling at established monitoring sites with consistent analytical methods. ISSN:2050-7887 ISSN:2050-7895

A thorough understanding of long-term temporal social-ecological dynamics at the national scale helps to explain the current condition of a country’s ecosystems and to support environmental policies to tackle future sustainability challenges. We aimed to develop a methodological approach to understand past long-term (1960-2010) social-ecological dynamics in Spain. First, we developed a methodical framework that allowed us to explore complex social-ecological dynamics among biodiversity, ecosystem services, human well-being, drivers of change, and institutional responses. Second, we compiled 21 long-term, national-scale indicators and analyzed their temporal relationships through a redundancy analysis. Third, we used a Bayesian change point analysis to detect evidence of past social-ecological thresholds and historical time periods. Our results revealed that Spain has passed through four socialecological thresholds that define five different time periods of nature and society relationships. Finally, we discussed how the proposed methodological approach helps to reinterpret national-level ecosystem indicators through a new conceptual lens to develop a more systems-based way of understanding long-term social-ecological patterns and dynamics, This work was supported by the Biodiversity Foundation (http://www.fundacion-biodiversidad.es/) of the Spanish Ministry of Agriculture, Food and Environment. Partial financial support was also provided by the Ministry of Economy and Competitiveness of Spain (project CGL2014-53782-P: ECOGRADIENTES). The Spanish National Institute for Agriculture and Food Research and Technology (INIA) funded Marina García-Llorente as part of the European Social Fund. Blanca González García-Mon participated in this article as a “la Caixa” Banking Foundation scholar. The funders had no role in the study design, data collection and analysis, preparation of the report, or the decision to submit the study for publication

The paper is focused on the evaluation of long-term changes in the chemical composition of precipitation in the mountain forests of Slovakia. Two stations with long-term measurements of precipitation quality were selected, namely the station of the EMEP (European Monitoring and Evaluation Programme) network Chopok (2008 m a.s.l.) and the station of the ICP Forests (International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests) network Poľana-Hukavsk&yacute, gr&uacute, ň (850 m a.s.l.). All basic chemical components were analyzed, namely sulfur (S-SO4), nitrogen (N-NH4, N-NO3), and base cations (Ca, Mg, and K) contained in precipitation. The time changes of the individual components were statistically evaluated by the Mann&ndash, Kendall test and Kruskal&ndash, Wallis test. The results showed significant declining trends for almost all components, which can significantly affect element cycles in mountain forest ecosystems. The evaluated forty one-year period (1987 to 2018) is characterized by significant changes in the precipitation regime in Slovakia and the obtained results indicate possible directions in which the quantity and quality of precipitation in the mountainous areas of Slovakia will develop with ongoing climate change.

Halocarbons are widely used in the Greater Pearl River Delta (PRD) region of China. To study the long-term trends, source changes and emissions of major halocarbons, a total of 1505 canister air samples were collected in the Greater PRD region during 2001–2018. Mixing ratios of CFCs decreased significantly over the past 18 years except for CFC-114, which significantly increased in the Greater PRD, consistent with the recent observations of significant CFC-114 emissions in East Asia. Declines in CFCs in the Greater PRD region were faster than those at the background Mauna Loa (MLO) site, indicating effective control regulations. Source apportionment simulations showed that refrigeration applications, including refrigeration industry and CFCs replacement, were the main sources of halocarbons. During the study period, refrigeration industry experienced a progressive decline in both mixing ratio and percentage, while the contribution of CFCs replacement remained increasing. Contribution of solvent use in electronic industry traced by C2Cl4 dramatically decreased during the study period, and stayed at a low level in recent years. Based on the measured ratios of halocarbons to CO, the estimated total halocarbon emissions in 2016 were 46.5 ± 16.7 Gg for the Greater PRD region. This study provides useful information for examining the evolving emission status of halocarbons in the Greater PRD region in response to control strategies and changing usage.

Choi, T.J.; Choi, J.Y.; Park, J.Y., and Yang, Y.J., 2020. Long-term temporal and spatial morphological variability of a nourished beach using the EOF analysis. In: Malvarez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 428–432. Coconut Creek (Florida), ISSN 0749-0208.Byeonsan Beach located at the west coast of Korea has been eroded seriously since 2006 after the construction of the Saemangeum dike. For this reason beach nourishment has been conducted from 2011 until 2017, and the result was successful by turning the beach in erosional phase of -4.1 cm/yr (2006 to 2010) into depositional condition of +2.0 cm/yr (2011 to 2017). Based on the EOF analysis of sixty-nine beach surveys during 13-year period from 2006 to 2019, the first four modes accounted for nearly 83% of total variability, leading to the interpretations of beach-nourishment effect, artificial construction, the influence of beach ridges migration, and irrigation-channel effect, respectively.

BackgroundIn earlier work, we examined whether the PM2.5-hospital admissions relative risk varies over time, using hospital admission data of U.S. Medicare beneficiaries and U.S. Environmental Prot...

We present evidence on the short-term differences in airborne pollution levels in terms of weekday/weekend (WD/WN) and weekday/Sunday (WD/Sun) intervals. To this end, we analyzed the hourly data of important pollutants (nitric oxide (NO), nitrogen dioxide (NO2), ozone (O3) and carbon monoxide (CO)) using the data acquired in the Yong-San district of Seoul, Korea from 2009 to 2013. For each week, the pollutant ratio (Rw) was estimated through either WD/WN or WD/Sun. Here, a week is defined as Sunday through Saturday, WD as Monday through Friday and WN as Sunday and Saturday. The WD/Sun Rw geometric means (and range) were 2.02 (0.27–15.5) for NO, 1.29 (0.49–5.7) for NO2 and 0.89 (0.17–7.2) for O3 while the fraction of Rw (WD/Sun) > 1 were 81, 71 and 38%, respectively. NO and CO levels were much higher in October through March (during Autumn and Winter) than April through September (during Spring and Summer), reflecting the potential effect of fuel consumption (e.g., in terms of use patterns of nationwide city natural gas). Thus, we provide a broader interpretation on the occurrence patterns of the major pollutants (e.g., NO, NO2, O3 and CO) in relation to temporal changes in man-made activities.

Deep convolutional neural networks have been great success for image based recognition tasks. However, it is still unclear how to model the temporal evolution of videos effectively by deep networks. While recent deep models for videos show improvement by incorporating optical flow or aggregating high level appearance across frames, they focus on modeling either the long term temporal relations or short term motion. We propose Temporal Difference Networks (TDN) that model both long term relations and short term motion from videos. We leverage a simple but effective motion representation: difference of CNN features in our network and jointly modeling the motion at multiple scales in a single CNN. It achieves state-of-the-art performance on three different video classification benchmarks, showing the effectiveness of our approach to learn temporal relations in videos.

Long-term trend of crop yields has been widely studied in global scales to find which crops and which geographic regions offer the best hope of meeting food demands, and which regions needed the most improvements. In this study, a mathematical method was applied to analyze spatial patterns in long-term temporal trends of three major crops’ yields in Japan archipelago. The changes in annual yields of rice, wheat, and soybean over a period of about 60 years in all 47 prefectures of Japan was analyzed by using the data of agricultural records. For all the three crops, the nationwide yields previously improved, but currently were stagnating in Japan. The result suggests that the annual yields were not improving in 53, 85, and 89% of those prefectures in Japan for rice, wheat, and soybean, respectively. The spatial patterns in temporal trends show that the percentage of number of yield-not-improving prefecture was higher in low latitude regions than high latitude regions. These results highlight the increasingly difficult challenge of meeting the growing demands and stagnating supplies in daily staple foods not only for agricultural scientists but also for Japanese society.

Much of the Baltic Sea is currently classified as 'affected by eutrophication'. The causes for this are twofold. First, current levels of nutrient inputs (nitrogen and phosphorus) from human activities exceed the natural processing capacity with an accumulation of nutrients in the Baltic Sea over the last 50-100 years. Secondly, the Baltic Sea is naturally susceptible to nutrient enrichment due to a combination of long retention times and stratification restricting ventilation of deep waters. Here, based on a unique data set collated from research activities and long-term monitoring programs, we report on the temporal and spatial trends of eutrophication status for the open Baltic Sea over a 112-year period using the HELCOM Eutrophication Assessment Tool (HEAT 3.0). Further, we analyse variation in the confidence of the eutrophication status assessment based on a systematic quantitative approach using coefficients of variation in the observations. The classifications in our assessment indicate that the first signs of eutrophication emerged in the mid-1950s and the central parts of the Baltic Sea changed from being unaffected by eutrophication to being affected. We document improvements in eutrophication status that are direct consequences of long-term efforts to reduce the inputs of nutrients. The reductions in both nitrogen and phosphorus loads have led to large-scale alleviation of eutrophication and to a healthier Baltic Sea. Reduced confidence in our assessment is seen more recently due to reductions in the scope of monitoring programs. Our study sets a baseline for implementation of the ecosystem-based management strategies and policies currently in place including the EU Marine Strategy Framework Directives and the HELCOM Baltic Sea Action Plan.

Disinfection by-products (DBPs) constitute a large family of compounds. Trihalomethanes and haloacetic acids are regulated in various countries, but most DBPs are not. Monitoring DBPs can be delicate, especially for small systems, because various factors influence their formation and speciation. Short-term variations of DBPs can be important and particularly difficult for small systems to handle because they require robust treatment and operation processes. According to our knowledge, for the first time, our study covers the short-term variability of regulated and non-regulated DBP occurrence in small systems in the summer. An intensive sampling program was carried out in six small systems in Canada. Systems in the provinces of Newfoundland and Labrador and Quebec were sampled daily at the water treatment plant and at six different locations along the distribution system. Five DBP families were studied: trihalomethanes, haloacetic acids, haloacetonitriles, halonitromethanes and haloketones. Results show that there were considerable variations in DBP levels from week to week during the month of study and even from day to day within the week. On a daily basis, DBP levels can fluctuate by 22% to 96%. Likewise, the large number of sampling locations served to observe DBP variations along the distribution system. Observations revealed some degradation and decomposition of non-regulated DBPs never before studied in small systems that are associated with the difficulty these systems experience in maintaining adequate levels of residual disinfectant. Finally, this study reveals that the short term temporal variability of DBPs is also influenced by spatial location along the distribution system. In the short term, DBP levels can fluctuate by 23% at the beginning of the system, compared to 40% at the end. Thus, spatial and temporal variations of DBPs in the short term may make it difficult to select representative locations and periods for DBP monitoring purposes in small systems.

Considerable theory explains the importance of understanding temporal variation in ecological processes. Nevertheless, long‐term variability in habitat selection is rarely assessed or even acknowledged. We explored temporal variability in the habitat selection of a top‐predator, the wolf (Canis lupus), at two time scales: interannual and seasonal variability. To do this, we developed resource utilization functions to relate wolf habitat selection to environmental variables in different years and seasons. We used radiotelemetry data collected from a wolf population in Yellowstone National Park during a 10‐year period (1998–2007) and added a Year variable in the models to account for interannual variation in the studied processes. We also used a three‐year data set (nested within the 10‐year data set) to incorporate additional variables in the models and test for differences in short‐ and long‐term patterns of habitat selection. Wolves exhibited seasonal variation in habitat selection with respect to distance from roads, elevation, openness, and habitat type. Habitat selection was considerably more complicated during the winter compared to summer, when wolves only selected habitat based on distance from roads. We detected clear patterns of habitat selection in the three‐year data set that could not be detected in the 10‐year data set, despite the longer data set had more statistical power for pattern detection. This observation is likely the result of the longer data set being comprised of several shorter‐term and countervailing patterns. This explanation is also consistent with having detected significant year effects in the 10‐year data set. Insomuch as habitat selection is important to conservation and management, this research is significant for demonstrating the different impressions that can be given by short‐term and long‐term studies. It may be common for short‐term data sets to suggest patterns of habitat selection that do not prevail over longer periods of time.

Major and trace metal concentrations were determined in western Adriatic sediment cores. Based on sediment chronology, the earliest anthropogenic influence appeared as a Zn and Pb increase in the Po River prodelta starting from ~. 1914. The increasing contamination signal of these trace metals propagated southward as far as 450. km with a growing delay, taking ~. 10. years to reach the south Adriatic Sea. Although greater inventories of excess trace metals in the northern sector pointed to the influence of the intense human activities in the Po River drainage basin and Venice lagoon system, we observed a reduction of excess trace metals from mid-1980s, related to the implementation of stricter environmental regulations on chemical wastewaters. In contrast, an increase in trace metal accumulation in surficial sediment from the 2000s in front of the cities of Ancona and Bari suggested a recent local input of trace metals, probably due to harbor activities.

One of the ways to assess the impacts of climate change on plants is analysing their long-term phenological data. We studied phenological records of 18 common tree species and their 8 phenological phases, spanning 65 years (1946-2010) and covering the area of the Czech Republic. For each species and phenophase, we assessed the changes in its annual means (for detecting shifts in the timing of the event) and standard deviations (for detecting changes in duration of the phenophases). The prevailing pattern across tree species was that since around the year 1976, there has been a consistent advancement of the onset of spring phenophases (leaf unfolding and flowering) and subsequent acceleration of fruit ripening, and a delay of autumn phenophases (leaf colouring and leaf falling). The most considerable shifts in the timing of spring phenophases were displayed by early-successional short-lived tree species. The most pronounced temporal shifts were found for the beginning of seed ripening in conifers with an advancement in this phenophase of up to 2.2 days year⁻¹ in Scots Pine (Pinus sylvestris). With regards to the change in duration of the phenophases, no consistent patterns were revealed. The growing season has extended on average by 23.8 days during the last 35 years. The most considerable prolongation was found in Pedunculate Oak (Quercus robur): 31.6 days (1976-2010). Extended growing season lengths do have the potential to increase growth and seed productivity, but unequal shifts among species might alter competitive relationships within ecosystems.

Background Takotsubo cardiomyopathy (TC) is an acute heart failure syndrome. Despite an often rapid recovery in left ventricular ejection fraction (LVEF), TC is associated with morbidity and mortality in select patients which may be due to persistent abnormalities in myocardial mechanics. Strain echocardiography quantifies myocardial deformation and is a sensitive marker of myocardial dysfunction. The aim of this study was to evaluate the short-term temporal changes in LVEF and myocardial deformation between presentation and close follow-up. Hypothesis Improvement in LVEF will occur prior to improvement in myocardial strain at short-term follow-up. Methods Patients with an ICD9/10 diagnosis code of TC were identified using the Northwestern University Enterprise Data Warehouse. All TC patients with echocardiograms at presentation and within 21 days of presentation were included. Two-dimensional speckle-tracking echocardiography (2DSTE) was performed using Tomtec Arena 2.21 software to assess LVEF, LV peak global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), as well as RV fractional area change (FAC) and peak free wall strain (FWS). Statistical analysis was performed using a paired samples Student's t-test with a p-value Results The study cohort included 80 patients with 80% females and mean age 65.6 ± 15.4 yrs. Patients were grouped by timing of follow-up echocardiogram: within 3 days, between 4-10 days, and between 11-21 days from presentation. Compared to baseline echocardiogram, there was significant improvement in LVEF (29.0% vs 37.6%, p = 0.001) and GLS (−10.6% vs −12.7%, p = 0.022) in patients with follow up echocardiograms within 3 days ( Table 1 ). Significant improvement in GCS (−15.3% vs −21.7%, p = 0.005) and GRS (24.2% vs 32.0%, p = 0.035) was not seen until 4-10 day follow up. At 21 day follow-up, significant improvement in RV FAC (27.5% vs 34.5%, p = 0.008) and RV FWS (−13.6% vs −18.4%, p = 0.002) was noted. Conclusion In our single-center cohort of TC patients, improvement in LVEF and GLS was noted relatively early after initial presentation. The improvement in GCS and GRS occurred later, indicating persistent cardiac dysfunction despite improved but not fully recovered LVEF. Furthermore, recovery in RV dysfunction occurred after improvement in all LV parameters. These persistent abnormalities in myocardial mechanics provide further insight into myocardial recovery in TC and the potential for improvements in risk stratification and management of these patients.

This paper focused on the temporal and spatial variability of sulphur dioxide (SO2) from 2004 to 2013 over 36 ground-based (GB) stations located in Gauteng and Mpumalanga provinces of South Africa. The assessment was based on the in situ SO2 data, where the GB stations were sorted into different groups and in addition, kriging-based analysis and OMI SO2 data (2004–2013) were deployed to study their seasonal spatial variability. It was observed that Pretoria west, Witbank and Randwater had high SO2 levels and standard deviations. Although, winter played a major role in having peak SO2 values in most of the stations, it was surpassing that in spring the SO2 levels of Witbank and Pretoria west stations dropped and Randwater had the highest standard deviation of 11.2 ppbv in October. A prominent seasonal variation was seen in all the groups, excluding Mpumalanga power stations (MP) group. This was particularly evident in the Vaal Triangle group. Highveld group ranked topmost level with elevated SO2 values proceeded by the MP group in all the temporal time scales. The spatial based analysis further proved that the highest SO2 levels were centred around major industrial regions of Mpumalanga, regardless of all the seasons.

Images of wide-angle visible standard CCD cameras contain information on in-vessel dusts such as dust creation events (DCEs) that occur during plasma operations, and their velocity. Analyzing the straight line-like dust traces in the shallow cylindrical shell-structured scrape-off layer along the vacuum vessel, a database on the short/long term temporal evolutions, spatial locations of DCEs caused by plasma–dust interaction, and the dust velocity distribution are built. We have studied DCEs of 2010 and 2011 KSTAR campaign.

Dissolved organic carbon (DOC) plays an important role in both terrestrial and aquatic ecosystems. In-stream DOC concentration is an important indicator of water quality, because high in-stream DOC concentrations naturally lead to reductions in dissolved oxygen. Recent studies indicate that DOC is responsible in transferring toxic metals (e.g., mercury, Hg) from terrestrial sources to aquatic ecosystems. However, assessing DOC or Hg dynamics is fairly challenging as a result of extreme spatiotemporal variation. Typically, process-based models with short-to-medium term temporal resolutions are required to model DOC and Hg dynamics. The objective of this research is to develop a watershed-based monthly DOC production and export model that integrates the treatment of (i) forest-litter decomposition (DOC production), (ii) wetland-to-watershed area ratio (DOC storage), and (iii) relevant hydrological processes (DOC export) in the simulation of in-stream concentrations. Model results are compared against DOC concentrations collected at the stream outlets of two separate forested watersheds in Kejimkujik National Park, Atlantic Canada. Comparisons for the two watersheds show that predicted monthly DOC concentrations are generally in good agreement with field-based concentrations, giving R2-values of 0.61 and 0.63 for Pine Marten Brook watershed and 0.72 and 0.75 for Moose Pit Brook watershed for model calibration and validation, respectively.