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Highlights: A method to investigate water consumption based on pressure data is developed. The method exploits the headloss-flowrate equation to obtain water-consumption data. The method is validated on a real case study, resulting in an average error of 2.3%. Limitations affecting the installation of domestic flow meters are overcome. Insights into the features of individual water-consumption events are provided. In the era of digital transformation of water distribution networks, an increasingly important role is played by smart metering technologies, which allow detailed characterization of water consumption up to the end-use (i.e., domestic-fixture) level. To this end, smart flow meters make the collection of water-consumption data at high temporal resolution possible, but their installation can be unfeasible due to technical and economic limitations. As an alternative to the traditional flow-measurement-based methods for end-use characterization, a pragmatic method to obtain information about end-use water consumption exclusively based on pressure data is proposed in this study. In particular, a dual-phase methodology is developed, exploiting (i) pressure data collected at two sections of the user's inlet pipeline and (ii) the pressure-flowrate relationship to discriminate between internal and external water-use events and estimate the household water-consumption time series, which is then subjected to individual-event analysis. The results obtained on a real case study undergone to 1-s resolution pressure monitoring over about one month and a half confirm the method's effectiveness in obtaining the flowrate time series with an average error of about 2.3% and successfully identifying water-consumption events along with their features. [ABSTRACT FROM AUTHOR]

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High‐resolution monitoring is fundamental to understand ecosystems dynamics in an era of global change and biodiversity declines. While real‐time and automated monitoring of abiotic components has been possible for some time, monitoring biotic components—for example, individual behaviours and traits, and species abundance and distribution—is far more challenging. Recent technological advancements offer potential solutions to achieve this through: (i) increasingly affordable high‐throughput recording hardware, which can collect rich multidimensional data, and (ii) increasingly accessible artificial intelligence approaches, which can extract ecological knowledge from large datasets. However, automating the monitoring of facets of ecological communities via such technologies has primarily been achieved at low spatiotemporal resolutions within limited steps of the monitoring workflow. Here, we review existing technologies for data recording and processing that enable automated monitoring of ecological communities. We then present novel frameworks that combine such technologies, forming fully automated pipelines to detect, track, classify and count multiple species, and record behavioural and morphological traits, at resolutions which have previously been impossible to achieve. Based on these rapidly developing technologies, we illustrate a solution to one of the greatest challenges in ecology: the ability to rapidly generate high‐resolution, multidimensional and standardised data across complex ecologies. [ABSTRACT FROM AUTHOR]

Herein, we conducted a study of the Zhangsanxi karst groundwater system in Zhangjiajie, Hunan Province, China, and used the results to develop a method for identifying the aquifer medium and its structural characteristics. To begin, rainfall, underground river flow dynamics, and groundwater level dynamics in the Zhangsanxi karst groundwater system were subjected to high-resolution monitoring to elucidate the groundwater system's rainfall-hydrological response characteristics under varying rainfall amounts and intensities. Next, an exponential attenuation curve was employed to analyze how the law of attenuation applies to underground river discharge and groundwater level during a typical rainfall event. Finally, we determined the degree of karst development at different depths, so the data can serve as a reference for local decision makers regarding karst water disaster prevention and water resource utilization. The results show that the flow response lag time in the karst groundwater system depicts good correlation with the rainfall amount but is also affected by the rainfall intensity. Thus, under conditions of identical rainfall, increasing rainfall intensity corresponds to a progressively shorter underground river flow lag time. The area's rainfall can be divided into four types, based on its concentration and intensity characteristics. The underground river flow generally has no evident response to type I rainfall, while the flow response lag time to types II III and IV rainfall is approximately 110, 60, and 40 h, respectively. Furthermore, the Zhangsanxi karst system's water-bearing medium is dominated by karst fissures and pores, which account for about 2/3 of its open space. Large karst conduits and caves account for the remaining 1/3. The degree of karst development in this system depicts evident depth variation but, overall, tends to increase as a function of burial depth. Responsible editor: Xianliang Yi. [ABSTRACT FROM AUTHOR]

Data centers are increasing in size and complexity, and we need scalable approaches to support their automated analysis and control. Performance counters and power consumption are their key "vital signs". State-of-the-Art (SoA) monitoring systems provide built-in tools to collect performance measurements, and custom solutions to get insight on their power consumption. However, with the increase in measurement resolution (in time and space) and the ensuing huge amount of measurement data to handle, new challenges arise, such as bottlenecks on the network bandwidth, storage and software overhead on the monitoring units. To face these challenges we propose a novel monitoring platform for data centers, which enables real-time high-resolution profiling (i.e., all available performance counters and the entire signal bandwidth of the power consumption at the plug—sampling up to 20 μ s —with an error below 1%) and analytics, both at the edge (node-level analysis) and on a centralized unit (cluster-level analysis). The monitoring infrastructure is completely out-of-band, scalable, technology agnostic and low cost, and it is already installed in a SoA high-performance compute cluster (i.e., D.A.V.I.D.E. —18th in Green500 November 2017). [ABSTRACT FROM AUTHOR]

Where rivers meet the sea, tides can exert a physical and chemical influence on the lower reaches of a river. How tidal dynamics in these tidal river reaches interact with upstream hydrological drivers such as storm rainfall, which ultimately determines the quantity and composition of material transferred from watersheds to estuaries, is currently unknown. We monitored a small freshwater tidal river in the Pacific Northwest, United States in high resolution over 1 year to evaluate the relative importance of tides vs. upstream hydrological flows (i.e., base flow and precipitation events) on basic physico-chemical parameters (pH, dissolved oxygen, turbidity, specific conductivity, and temperature), and how these interactions relate to the downstream estuary. Tidal variability and diurnal cycles (i.e., solar radiation) dominated water physico-chemical variability in the summer, but the influence of these drivers was overshadowed by storm-driven sharp pulses in river physico-chemistry during the remainder of the year. Within such events, we found incidences of counterclockwise hysteresis of pH, counterclockwise hysteresis of dissolved oxygen, and clockwise hysteresis of turbidity, although systematic trends were not observed across events. The dominance of storm rainfall in the river’s physico-chemistry dynamics, and similar pulses of decreased pH observed in adjacent estuarine waters, suggest that the linkage between tidal streams and the broader system is variable throughout the year. High-frequency monitoring of tidal river biogeochemistry is therefore crucial to enable the assessment of how the relative strength of these drivers may change with future sea level rise and altered precipitation patterns to modulate biogeochemical dynamics across the land-ocean-atmosphere continuum.

A 3-year high-resolution monitoring of shallow subsurface temperature (unsaturated and saturated zones) was performed in the experimental site of Mezzi Po (Po River plain, NW Italy) to investigate the thermal behaviour of subsurface and the dependency with the atmospheric (air) temperature. The unsaturated zone of the test site is mainly constituted by sands and silts, and the unconfined aquifer below is hosted in coarse sediments (mainly sands and gravels) with shallow depth to water table (5 m b.g.l). The monitoring results allowed for identifying two main phenomena correlated with the propagation of the atmospheric heat through the subsurface. First, the amplitude of temperature fluctuation during the year, calculated as the difference between maximum and minimum temperature value, reduces with increasing depth, with a maximum range (31.1 °C) in air and a minimum (2.0 °C) in the saturated zone, at 7.00 m below ground level (b.g.l.). Furthermore, a lag of mean temperatures in the subsurface respect to air occurs. The delay is as much longer as the depth increases. Mainly, the time shift ranges between 1 week in the shallow soil (at 0.60 m b.g.l.) and 17 weeks in the saturated zone (7 m b.g.l.). These results are consistent with a 1-D heat diffusion model, through which the thermal subsoil properties were derived for 0.60–7 m depth interval. More specifically, thermal diffusivity is 8.12 × 10–7 m2/s, and thermal conductivity is 1.40 W/mK. [ABSTRACT FROM AUTHOR]

• Identifying two fates of CO 2 generated by H 2 SO 4 and/or HNO 3 to estimate CO 2 emission. • Rainfall improved carbon sink flux by reducing CO 2 emission. • The δ13C DIC did not reflect the contribution of H 2 SO 4 and/or HNO 3 to karstification. To determine the mechanism underlying the effect of rainfall on the karst-related carbon cycle while controlled by that of H 2 SO 4 and/or HNO 3 , high-resolution monitoring was conducted in Lanhuagou Spring, which is a typical epikarst spring in southwest China. During the monitoring period, the signals from major elements and stable isotopes showed that the CO 2 generated by H 2 SO 4 and/or HNO 3 entirely escaped from the water. Therefore, the CO 2 consumption induced by H 2 CO 3 and CO 2 emission induced by H 2 SO 4 and/or HNO 3 jointly affected the karst-related carbon cycle. The CO 2 consumption induced by H 2 CO 3 dropped following rainfall events and recovered gradually thereafter, which was only affected by the retention time of infiltrating water (dilution effect of rainfall). However, the CO 2 emission induced by H 2 SO 4 and/or HNO 3 had showed a downward trend from the first rainfall event (R1) to the end of monitoring. The effects of rainfall on CO 2 emission induced by H 2 SO 4 and/or HNO 3 were related to both the dilution effect and the removal of H 2 SO 4 and/or HNO 3. Although the average CO 2 consumption induced by H 2 CO 3 dropped from 2.8 mmol/L before rainfall to 2.21 mmol/L thereafter (decreased by 21.07 %), the average CO 2 emission induced by H 2 SO 4 and/or HNO 3 dropped from 1.29 to 0.49 mmol/L (decreased by 62.02 %); the range of CO 2 emission induced by H 2 SO 4 and/or HNO 3 decline (0.8 mmol/L) was larger than that of CO 2 consumption induced by H 2 CO 3 (0.59 mmol/L), resulting in higher net CO 2 consumption (CO 2 consumption induced by H 2 CO 3 minus CO 2 emission induced by H 2 SO 4 and/or HNO 3) after rainfall than before rainfall in the monitoring period. Therefore, in the model used to predict karst-related carbon flux caused by global climate change, it is necessary to consider the impact of rainfall on CO 2 emission induced by H 2 SO 4 and/or HNO 3. Importantly, the net CO 2 consumption rather than CO 2 consumption induced by H 2 CO 3 , as well as runoff should be considered as two multipliers when carbonate weathering is interfered by H 2 SO 4 and/or HNO 3. [ABSTRACT FROM AUTHOR]

Tidal processes regulating sediment accretion rates and vegetated platform erosion in tidal systems strongly affect salt marsh evolution. A balance between erosion and deposition in a restored salt marsh is crucial for analyzing restoration strategies to be adopted within a natural context. Marsh morphology is also coupled with tidal mudflats and channel networks and this makes micro-tidal systems crucial for a detailed assessment of restoration interventions. Here, we present a methodological approach for monitoring channel morphodynamics and vegetation variations over a time frame of six years in a low tidal energy salt marsh of the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island (Maryland, USA). The project is a restoration site where sediment dredged from the shipping channels in the upper Chesapeake Bay is used to restore a tidal marsh habitat in mid-Chesapeake Bay. Aerial surveys with an Unmanned Aerial Vehicle (UAV) have been performed for the high-resolution mapping of a small tidal system. Flight missions were planned to obtain a Ground Sample Distance (GSD) of 2 cm. Structure-from-Motion (SfM) and Multi-View-Stereo (MVS) algorithms have been used to reconstruct the 3D geometry of the site. The mapping of channel morphology and an elevation assessment on the mudflat were performed using orthomosaics, Digital Terrain Models (DTMs) and GNSS survey. The results highlight that the workflow adopted in this pilot work is suitable to assess the geomorphological evolution over time in a micro-tidal system. However, issues were encountered for salt marsh due to the presence of dense vegetation. The UAV-based photogrammetry approach with GNSS RTK ground surveys can hence be replicated in similar sites all over the world to evaluate restoration interventions and to develop new strategies for a better management of existing shorelines.

Low dissolved oxygen concentrations are of increasing concern in aquatic ecosystems, particularly at the interface between freshwater and marine environments. Oxygen depletion occurs naturally in many perennially stratified systems and it remains to be seen how climate change will affect these habitats. This is due, in part, to a lack of highresolution, long-term data describing interannual variability in dissolved oxygen concentrations within stratified basins. Physicochemical parameters for Lough Furnace, an ecologically important tidal lagoon, were assessed using daily measurements (2009-14) from an undulating CTD (conductivity, temperature and depth) profiler and observations of tidal exchange flow. Continuous vertical saline stratification existed, with anoxia (> 0.1 mg L -1) typically persisting below 6 m. Tidal inflows were generally restricted, with deep-water renewal events by intrusions of denser spring tidal water occurring episodically (three times in 6 years), following prolonged periods of low freshwater input. Although wind forcing alone was not sufficient to generate basin-scale mixing, the conditions that led to deep-water renewals may also be conducive to wind-driven upwelling events in nearshore areas. These findings have wider application to larger-scale twolayered stratified systems with deep anoxia because the ability to forecast such dynamic events is important for assessing the ecological implications of dissolved oxygen depletion. [ABSTRACT FROM AUTHOR]

Load calculations of nutrients and suspended solids (SS) transported by rivers are usually based on discrete water samples. Water quality changes in cold climate regions often occur very rapidly and therefore discrete samples are unrepresentative of the range of water quality occurring. This leads to errors of varying magnitude in load calculation. High-resolution turbidity data were used to determine the SS and total phosphorus (TP), and paired with discharge to determine loads from two small catchments in southern Finland. The effect of sampling frequency was investigated by artificially sub-sampling the high frequency concentrations. Regardless of the sampling frequency, the TP load was more likely underestimated while using discrete samples. To achieve ±20% accuracy compared with the reference load, daily sampling should be performed. Hysteresis was detected to have an impact on TP load. Hysteresis analysis also revealed the main source of the TP to be in the fields of the catchment. Continuous measuring proved to be a valuable method for defining loads and short-term fluctuations in water quality in small clayey watercourses in a boreal cold climate, where the climate change will increase the frequency of winter floods. [ABSTRACT FROM AUTHOR]

This paper presents the hydrological and water quality response from a series of extreme storm events that passed across the UK during the winter of 2013/2014, in an experimental catchment with a strong rural-urban gradient across four nested sub-catchment areas. The Ray catchment in the upper Thames basin, UK, was extensively monitored using in-situ, high-resolution (15 min) flow and water quality instrumentation. Dissolved oxygen, ammonium, turbidity and specific conductivity are used to characterise the water quality dynamics. The impact of the Swindon sewage treatment works (SSTW) on water chemistry at the catchment outlet is considerable. Hydrological and water-quality response varies considerably during the events, with the rural catchments exhibiting a much slower hydrological response compared to urban areas. A simple hydrological model (TETIS) was developed to provide insight into water sources in nested subcatchments, highlighting the disparity of the hydrological dynamics across contrasting land-uses during events. The variation in stormwater runoff sources impacts water quality signals with urban sites contributing to dilution dynamics in ammonium, whereas the more rural site experiences a peak in ammonium during the same event. Dissolved oxygen concentrations vary on a rural-urban gradient and experience a notable sag at the Water Eaton outlet (4.4 mg/l) during the events, that would have resulted in significant ecological harm had they occurred during the summer in warmer temperatures. The water-quality legacy of these storms in the wider context of the hydrological year is somewhat negligible, with markedly poorer water quality signals being observed during the summer months of 2014. Although ammonium concentrations during the events are elevated (above the ‘good’ status threshold under the WFD), higher values are observed during spring and summer months. The high flows actually appear to flush contaminants out of the Ray and its subcatchments, though the urban sites demonstrate a resupply dynamic during interim dry periods. Data suggest winter storms following dry spells in urban catchments cause some short-lived and spatially extensive deteriorations in water quality. More chronic effects, although prolonged, are only seen downstream of SSTW. These are indicative of capacity of infrastructure being reached, and from the data do not appear to be severe enough to cause ecological harm. [ABSTRACT FROM AUTHOR]

Abstract: The Nitrates Directive regulations are a Programme of Measures under the EU Water Framework Directive to protect waters from agricultural transfers of nitrogen and phosphorus. Soil phosphorus management to an agronomic optimum and closed winter periods for organic and inorganic fertiliser amendments are among a suite of policy measures to curtail diffuse pollution at catchment scale. In this investigation, two intensive grassland and two arable catchments (7–12km2) in the Republic of Ireland were studied to link a high resolution spatial survey (≤2ha) of soil P availability with P delivery in receiving rivers; monitored on a sub-hourly basis over one year. Data indicated that source risk, as defined by soil P availability and organic P loading, was less important than mobilisation and hydrological transfer potential which increased delivery due to runoff flashiness as described by a hydrological metric during the winter. Overall, however, annual TP loads were low to moderate (0.175 to 0.785kgha−1 yr−1). The data also highlighted, without exception, the influences of summer background P loading and subsequent ecologically significant P concentrations from persistent point sources. This may have implications for expected ecological status and recovery in these catchments, which appeared more at risk in catchments with little buffering in terms of summer base flow dilution. Wetter winters and drier summers under climate change scenarios would likely increase stream P concentrations both during storms and during baseflows and would be particularly magnified in those catchments with flashy runoff and suppressed baseflow. These seasonal insights into source-to-delivery functions and risk (re)assessment were only possible with high resolution (spatial and temporal) data collection and will be important in influencing expectations of policies that are evaluated at larger scales but with coarser resolution sampling. [Copyright &y& Elsevier]

Abstract: Rural point sources of phosphorus (P), including septic tank systems, provide a small part of the overall phosphorus budget to surface waters in agricultural catchments but can have a disproportionate impact on the low flow P concentration of receiving rivers. This has particular importance as the discharges are approximately constant into receiving waters and these have restricted dilution capacity during ecologically sensitive summer periods. In this study, a number of identified high impact septic systems were replaced with modern sequential batch reactors in three rural catchments during a monitoring period of 4years. Sub-hourly P monitoring was conducted using bankside-analysers. Results show that strategic replacement of defective septic tank systems with modern systems and polishing filters decreased the low flow P concentration of one catchment stream by 0.032mgTPL−1 (0.018mgTRPL−1) over the 4years. However two of the catchment mitigation efforts were offset by continued new-builds that increased the density of septic systems from 3.4km−2 to 4.6km−2 and 13.8km−2 to 17.2km−2 and subsequently increased low flow P concentrations. Future considerations for septic system mitigation should include catchment carrying capacity as well as technology changes. [Copyright &y& Elsevier]

Abstract: Owing to intensified use of the coastal region and the frequent application of small-scale, tailored interventions such as beach nourishments, there is a growing need for coastal state information and knowledge on spatiotemporal scales of meters to kilometers and days to months. The design and implementation of engineering and management measures at these scales is hampered by limited predictability of their impact. Advanced, automated video stations open the door towards the collection of long-term, high-resolution data sets, which offer enhanced opportunities for the prediction of coastal processes at smaller scales. In this paper, the added value of high-resolution data sets for prediction purposes is explored. In particular the application of data-driven approaches as well as process models supported by video data are explored. In the data-driven approach, the inclusion of monthly video-derived data was found to not only improve confidence intervals on the predicted shoreline evolution, but also to facilitate the use of more sophisticated data extrapolation methods. Short-term, operational forecasts of the nearshore flow and sediment transport field were found to benefit from the inclusion of intertidal bathymetric data derived from video imagery. Though in its pioneering stage for video-based research, it is foreseen that significant advancement in prediction skill will be achieved through development of data-assimilation schemes which combine the best of existing process and empirical knowledge on coastal morphodynamics. [Copyright &y& Elsevier]

High-resolution measurements of total phosphorus (TP) concentrations in a stream draining a 5 km² agricultural catchment (a sub-catchment of Lough Neagh in Northern Ireland) were made every 10 mins by continuous flow instrumentation using new homogenisation, digestion and colorimetric phases. Concurrently, rainfall and stream discharge data were collected at 5 and 15 min. intervals. Major P flushing episodes during storm events peaked on the rising limbs of storm hydrographs. A period of baseflow also indicated the importance of other sources that maintain the stream in a eutrophic state between storm events. These data provide insights into catchment processes that conform to definite patterns that, in coarser sampling regime, might ordinarily be attributed to sampling and analytical 'noise.' [ABSTRACT FROM AUTHOR]

Although cliffs form approximately 75% of the world's coastline, the understanding of the processes through which they evolve remains limited because of a lack of quantitative data on the morphological changes they undergo. In this paper the combination of terrestrial time-of-flight laser scanning with high-resolution digital photogrammetry is examined to generate high-quality data-sets pertaining to the geomorphic processes governing cliff development. The study was undertaken on a section of hard rock cliffs in North Yorkshire, UK, which has been monitored over a 12-month period. High-density, laser-scanned point clouds have been used to produce an accurate representation of these complex surfaces, free from the optical variations that degrade photographic data. These data-sets have been combined with high-resolution photographic monitoring, resampled with the fixed accuracies of the terrestrial laser survey, to generate a new approach to recording the volumetric changes in complex coastal cliffs. This has led to significant improvements in the understanding of the activity patterns of coastal cliffs. [ABSTRACT FROM AUTHOR]

Tidal processes regulating sediment accretion rates and vegetated platform erosion in tidal systems strongly affect salt marsh evolution. A balance between erosion and deposition in a restored salt marsh is crucial for analyzing restoration strategies to be adopted within a natural context. Marsh morphology is also coupled with tidal mudflats and channel networks and this makes micro-tidal systems crucial for a detailed assessment of restoration interventions. Here, we present a methodological approach for monitoring channel morphodynamics and vegetation variations over a time frame of six years in a low tidal energy salt marsh of the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island (Maryland, USA). The project is a restoration site where sediment dredged from the shipping channels in the upper Chesapeake Bay is used to restore a tidal marsh habitat in mid-Chesapeake Bay. Aerial surveys with an Unmanned Aerial Vehicle (UAV) have been performed for the high-resolution mapping of a small tidal system. Flight missions were planned to obtain a Ground Sample Distance (GSD) of 2 cm. Structure-from-Motion (SfM) and Multi-View-Stereo (MVS) algorithms have been used to reconstruct the 3D geometry of the site. The mapping of channel morphology and an elevation assessment on the mudflat were performed using orthomosaics, Digital Terrain Models (DTMs) and GNSS survey. The results highlight that the workflow adopted in this pilot work is suitable to assess the geomorphological evolution over time in a micro-tidal system. However, issues were encountered for salt marsh due to the presence of dense vegetation. The UAV-based photogrammetry approach with GNSS RTK ground surveys can hence be replicated in similar sites all over the world to evaluate restoration interventions and to develop new strategies for a better management of existing shorelines. [ABSTRACT FROM AUTHOR]