Drainage Regime Research Articles

Impacts of forest canopy heterogeneity on plot-scale hydrometeorological variables - Insights from an experiment in the humid boreal forest with the Canadian Land Surface Scheme

High latitude regions, including the circumpolar boreal biome, are experiencing important changes in the availability of usable surface water because of climate change. In this context, an adequate representation of the land-atmosphere interaction is critical to ensure optimal management of current and future water resources, forest management, and climate prediction. However, the task is particularly intricate in high-latitude boreal forest, as land surface model faces several challenges due to the unique environmental conditions and ecological characteristics. The objective of this study is to quantify the impact of forest landscape heterogeneity, specifically stand leaf-area index (LAI), soil texture, and drainage regime, on surface water and energy balance in a small boreal high-latitude sub-catchment. To this end, hydrometeorological conditions at seventeen 20×20 m plots in a 1-km2 boreal forest sub-basin are simulated using the Canadian Land Surface Scheme (CLASS), a land surface model, at the point scale. The subplot-scale soil texture, drainage regime, and vegetation characteristics and type are based as closely as possible on field measurements and observations for the 17 plots. The model-driven experiment comprises two sets of simulations using CLASS, each employing the same model setup and run for the 17 experimental plots. The main set employs meteorological forcing from a local micrometeorological tower within the sub-basin to investigate the plot-to-plot variability of albedo, energy fluxes, and soil state variables. A second set of simulations is conducted using meteorological forcing from the ERA5-Land reanalysis, which spans from 1986 to 2022. This data provides a longer time series, enabling a more accurate representation of the interannual climatic variability in the sub-basin. The results of the main and secondary sets of CLASS simulations are used to assess the plot-to-plot and temporal variability of several key hydrometeorological variables by calculating a monthly spread. In brief, the following conclusions and broader implications can be drawn from the findings: i) The simulated total annual evapotranspiration remains relatively uniform between plots despite notable variation in its partitioning from plot to plot. ii) In the presence of a full snowpack, the albedo exhibits substantial heterogeneity at the subplot scale, linked to the canopy's LAI. iii) Local soil properties, drainage regime, and vegetation structure and type exhibit substantial influence on the plot-to-plot variability in soil water content. iv) When parameterized with localized observations and measurements, CLASS can represent and be responsive to the complex dynamics of energy and water fluxes at the plot scale within the heterogeneous surface of boreal forests.

Multifunctional Roles of Zinc in Cadmium Transport in Soil-Rice Systems: Novel Insights from Stable Isotope Fractionation and Gene Expression.

The effect of Zn on Cd accumulation in rice varies under flooding and drainage conditions, and the underlying mechanism during uptake and transport from the soil to grains remains unclear. Isotope fractionation and gene expression were investigated using pot experiments under distinct water regimes and with Zn addition to gain a deeper understanding of the molecular effects of Zn on Cd uptake and transport in rice. The higher OsHMA2 expression but constitutively lower expression of zinc-regulated, iron-regulated transporter-like protein (ZIP) family genes in roots under the drainage regime than the flooding regime caused the enrichment of nonheavy Zn isotopes in the shoots relative to roots but minimally affected Cd isotopic fractionation. Drainage regime seem to exert a striking effect on the root-to-shoot translocation of Zn rather than Cd, and increased Zn transport via OsHMA2. The changes in expression patterns in response to Zn addition were similar to those observed upon switching from the flooding to drainage regime, except for OsNRAMP1 and OsNRAMP5. However, soil solution-to-rice plants and root-to-shoot fractionation toward light Zn isotopes with Zn addition (Δ66Znriceplant-soilsolution = -0.49 to -0.40‰, Δ66Znshoot-root = -0.36 to -0.27‰) indicated that Zn transport occurred via nonspecific uptake pathways and OsHMA2, respectively. Accordingly, the less pronounced and minimally varied Cd isotope fractionation suggested that OsNRAMP5 and OsHMA2 are crucial for Cd uptake and root-to-shoot transport, respectively, facilitating Cd accumulation in grains. This study demonstrated that a high Zn supply promotes Cd uptake and root-to-shoot transport in rice by sharing distinct pathways, and by utilizing a non-Zn-sensitive pathway with a high affinity for Cd.

Effect of particles on foam drainage

Despite many applications, the three phase foam is so complicated and far from being fully understood. Drainage is critical to foam decay, so the effect of particles on foam drainage has been investigated in this research to better understand the complex three phase foam. The power law relationship, drainage regime, foam permeability and the residual solid particles were investigated with different particle concentration, particle hydrophobicity and particle size. It was found that the power law index increased with the increasing of particle concentration and particle hydrophobicity, which indicates the transition of drainage regime from node dominated to Plateau border dominated. It was also found that the medium size particles could increase the Plateau border viscous loss more obviously. Foam permeability with different particles was also discussed via fitting the viscous loss of both Plateau border and nodes. Finally, residual solid particle was used to study the particle behaviour during the free drainage after forced drainage. This research could help us better understand the drainage of three phase foam.

ИССЛЕДОВАНИЕ СИГНАЛЬНОГО НАЛОЖЕНИЯ ГИДРАВЛИКИ В МОДЕЛЯХ ПУСТОТ КАК ОБОСНОВАНИЕ ЭЛЕКТРОМЕТРИИ ДЛЯ КАРТИРОВАНИЯ КАРСТОПРОЯВЛЕНИЙ

The study of the karst territories for their use for optimal placement of subsurface use facilities, as well as the construction of engineering structures on them, is an important geotechnological and operational task. Based on the calculation of the hydraulic parameters of the geological environment, the article shows that karst objects are the cause of the formation of drainage regime and water loss, up to the drainage of this environment. It has been established that even small sizes of karst voids lead to fluctuations in the level of deep waters (UGW) and the formation of aeration layers. It is determined that in watered, deep strata, exploration and monitoring of karst objects is sufficiently reliable, in combination with the analysis of measured filtration rates according to the hydraulic model, methods of resistivimetry and thermometry of wells provide. Whereas, when mapping karsts above the UGV and in the covering strata, it is advisable to rely on the identification of signal aeration and dehumidification of the medium using the electrometric method, based on the connection of models of hydraulics and fields of electrical conductivity. The principal possibilities of geophysical methods of karst mapping are considered. It is established that the depth and coverage of exploration should exceed the size of the focus of filtration disturbances in the studied arrays. It is shown that the registration of high-frequency signals does not allow to ensure the reliability of the assessment of karstological safety.

Seasonal activity of anaerobic dehydrogenase of peat soils as related with some chemical factors of the redox environment of drained forest mires

The aim of the study was to study the specifics of seasonal fluctuations of anaerobic dehydrogenase of peat soils under the influence of forestry hydromelioration, a powerful exogenous factor affecting the speed and direction of biochemical processes. Location and time of the study. The southern taiga one of West Siberia during June–October 2001–2003 (geographical coordinates 56°23'071" NL, 84°34'04" EL). Methods. Investigation of the seasonal dynamics of the activity of anaerobic dehydrogenase and chemical components of the soil environment – C, NH4+, Fe2+, Fe3+, Fec (associated with organic matter) using the method of systemic ecological analysis. Results. The profile of drained forest peat soils was clearly differentiated into three zones: 0-5 cm of high anaerobic dehydrogenase activity, 5-10 cm of moderate activity and 10-30 cm of low activity of the enzyme. The main trend in seasonal fluctuations of the dehydrogenase activity from June to October was approximated by a second-order parabola. According to the regression equation parameters, in poorly drained soils the weekly increase in dehydrogenase activity averaged 0,205 units with a weekly average deceleration of 0,022. In the strongly drained soils, there was a weekly deceleration by an average of 0,131 with a weekly average acceleration of 0,022 units. Positively increased activity of anaerobic dehydrogenase was measured in 0-5 cm soil horizons, with the highest rates detected under poor drainage. Downwards the profile, there was mainly a negative increase during the entire observation period. A functional relationship between the activity of anaerobic dehydrogenase, mobile forms of iron, water-soluble organic matter and ammonium of medium and high density according to the type of parabola was revealed. Conclusions. The chemical components of the aqueous extract are the most important environmental factors controlling the kinetics of enzymatic reactions of peat soils. The cumulative proportion of the explained dispersion of dehydrogenase activity by mobile forms of iron (Fe2+, Fe3+, Fec) was 61 and 41%, by biogenic elements (organic matter and NH4+) – 25 and 44% respectively in weakly and intensively drained soils. The dominant factors determining seasonal fluctuations of the enzyme are iron-organic complexes and ammonium, regardless of the drainage regime, and oxidized iron under poor and reduced iron under strong drainage, respectively.

Effect of foam instability on drainage regime in forced drainage

Forced drainage has been widely used to study foam drainage regimes. Correct and accurate drainage regime of two phase foam is the base for better understanding the complicated three-phase froth. However, anomalies in data were uncovered in the presence of foam instability. Movement of bubbles in different foam instability conditions was firstly studied. Then, it was discussed that how the foam instability affected the power law relationship and the drainage regime. The power law index increased with the wider fitting range of liquid superficial velocity. Finally, the factors influencing foam instability and the power law relationship were analysed, including the position of imposed liquid, bubble size, and foam drying time. This paper advances our understanding of forced drainage in terms of foam instability.

Evaluation of the interFoam solver in the prediction of immiscible two-phase flow in imbibition and drainage on the pore-doublet system

Drainage and imbibition at low to moderate capillary number, are very important phenomena, in which the SCAL data are derived. In this venue, there is an increasing trend to apply computational fluid dynamic models at pore scale to extract the required parameters for multiphase flow study. Before applying these methods, their abilities to capture the real performance of fluids at the pore scale with corresponding capillary numbers should be validated. Moreover, due to the dimensional difference from pore to core scale, rigorous statistical methods are required to successfully extract the corresponding SCAL parameters. Hence for any model, before constructing any SCAL data via digital methods, validation at the pore scale along with the investigation of the possible effect of the dimensional change from pore to core scale are significant priorities. In this study, the performance of interFoam, a solver for immiscible two-phase flow from OpenFOAM, at the pore scale is evaluated. An image of the pore doublet system is digitized and meshed with different resolutions to capture the contact angle movement. The average pore diameters are different, and the pore diameter pathway varies. The experimental results are extracted from an article, which extensively performed the tests for different imbibition and drainage regime on this pore doublet system. Moreover, a sensitivity analysis on mesh geometry, refinement near boundaries, and contact angle is conducted. The drainage simulation and experimental results in the pore doublet system are in good agreement with each other. As expected, the displacement happens in the larger diameter and bypasses the wetting fluid in the narrow constriction. In imbibition, the displacement first takes place in the smaller constriction and then the wetting phase starts invading the larger diameter pore. From the sensitivity analysis, it is concluded that the instability of the front is mainly related to the slip condition at the walls. Moreover, the spreading of wetting film near the wall is prevalent at very low contact angles. The results show that the solver can predict the flow behavior in imbibition and drainage on the pore doublet system and the results are comparable with the experiments.

GIS MULTITEMPORAL ANALYSIS OF REMOTE SENSING IMAGES TO ASSESS THE SILTING OF ANTHROPOGENIC DAM LAKES IN THE OUTER SUBCARPATHIAN AREA. CASE STUDY: PUCIOASA ACCUMULATION LAKE, ROMANIA

On Romania's territory, after the major floods that took place during the 70s, the hydrotechnical setup of the large rivers that drain the peri-Carpathian areas was made. The purpose of building these anthropogenic dam lakes is complex, given that extreme hydrological phenomena occurred in late spring and early summer, caused by a significant rainwater supply (about 70%), the difference being made up by the underground supply. Such a hydrotechnical setup was made in the Subcarpathian areas, on large rivers, to mitigate flood waves, but also to create water resources to supply local communities. The main problem facing these lakes is the massive silting due on the one hand to the geological and geomorphological characteristics of the Subcarpathians and, on the other hand, to the high degree of anthropization. The Subcarpathians are, from a geological point of view, made up of friable deposits (marls, clays, marl-clays, gypsums, conglomerates), which trigger a series of geomorphological processes of slope erosion (areal streaming, ravine creation, runoffs, torrential rainfall, and landslides), all of which are involved in the hydrological drainage regime. The Subcarpathians also make up a geographical area with a high density of population and, implicitly, of anthropogenic activities, which under certain conditions favour the erosion and degradation of land. These factors ensure that the solid flow recorded on the Subcarpathian Rivers is between 5-25 million tons/ha per annum. All this leads to the intense silting of anthropogenic lakes, which causes the volume of water stored in the tank to sometimes decrease to 1/3 of its initial volume. Under these conditions, in the extremity of basins, lacustrine plains were formed, and within the dam area, the pelitic sedimentary deposits exceeded 7-10 m in thickness. The aim of this study is to perform a multitemporal analysis of lake silting in the Subcarpathian area by using GIS and integrating the suite of bathymetric elevations and the series of satellite images existing from the time of the lake's construction to present-day.

The role of soils in the regulation of ocean acidification.

Soils play an important role in mediating chemical weathering reactions and carbon transfer from the land to the ocean. Proposals to increase the contribution of alkalinity to the oceans through ‘enhanced weathering’ as a means to help prevent climate change are gaining increasing attention. This would augment the existing connection between the biogeochemical function of soils and alkalinity levels in the ocean. The feasibility of enhanced weathering depends on the combined influence of what minerals are added to soils, the formation of secondary minerals in soils and the drainage regime, and the partial pressure of respired CO2 around the dissolving mineral. Increasing the alkalinity levels in the ocean through enhanced weathering could help to ameliorate the effects of ocean acidification in two ways. First, enhanced weathering would slightly elevate the pH of drainage waters, and the receiving coastal waters. The elevated pH would result in an increase in carbonate mineral saturation states, and a partial reversal in the effects of elevated CO2. Second, the increase in alkalinity would help to replenish the ocean's buffering capacity by maintaining the ‘Revelle Factor’, making the oceans more resilient to further CO2 emissions. However, there is limited research on the downstream and oceanic impacts of enhanced weathering on which to base deployment decisions.This article is part of the theme issue ‘The role of soils in delivering Nature's Contributions to People’.

Improving the dimensioning of closed collecting and drainage network of drainage systems

Research relevance. Climatic changes determine the need to ensure a high productivity of drained lands through the use of appropriate adaptive measures for regulating and accumulating moisture in the soil. Therefore, the issue of changing approaches to the creation and operation of water reclamation facilities on drained lands gains relevance. Relevant are also changes in the methodology of projects for drainage systems construction and reconstruction and their optimal design solutions (type, design, systems parameters, and components of their technical elements) in the closed collecting and drainage network. In this case, the closed collecting and drainage network is a key element of the drainage system, which can operate in the drainage and soil moisture regime. 
 Aim of the study is to reveal new approaches to improving the methods of dimensioning the closed collecting and drainage network of drainage systems operating in the regime of drainage and soil moisture, based on justifying the relationship and considering the impact of network efficiency on the efficiency of water regulation on drained lands.
 Research methods. The analysis and generalization of the existing researches and methods on justification of the type, design, and parameters of the closed collecting and drainage network in the regime of drainage and soil moisture of the drained lands is executed. Systems approach and systems analyses were used to determine the existence of a structural relationship between the operation regime of the closed collecting and drainage network and the water regime of the drained lands. In performing the theoretical research, methods of mathematical modeling of the hydrodynamic structure of turbulent flow in pressure pipes using Navier-Stokes differential equations were applied. To confirm the adequacy of the obtained analytical models, the methods of statistical processing of experimental research results by Nikuradze I., Shevelyov F.O., and Altshul A.D. were used.
 Research findings and main conclusions. Thus, based on the performed theoretical and experimental research, we have proposed relatively new scientific positions in contrast to the semi-empirical theories for determining the hydrodynamic structure of the flow in the pressure pipe. This allows for dimensioning the entire hydrodynamic structure for all areas of the turbulent flow based on the application of the obtained universal equations. That is, we can construct a distribution profile of the total turbulent kinematic viscosity, averaged velocity, tangential stresses, and angular velocities of fluid particles. 
 Prospects. The presented approach will make it possible to determine the efficiency of flow in drainage pipes and in a closed collecting and drainage network. Also, this approach will further be helpful in improving the methods of designing and dimensioning technological and structural parameters of the network and ensuring the overall technical, technological, economic, and environmental efficiency of drainage systems.

Dissolved organic carbon loss from paddy fields by drainage and roles of common ions

Cations and anions exerted important effects on dissolved organic carbon (DOC) release and retention in arable soils. However, knowledge is limited on DOC loss from rice (Oryza sativa L.) paddies by drainage and its association with common ions under a conventional irrigation and drainage regime. This study aimed to investigate DOC dynamics in the soil-overlying water system and the synergistic behaviors of common ions (Na+, K+, Ca2+, Mg2+, Cl−, NO3− and SO42−) contributing to variations in DOC flux in drainage water at the pre-growing, vegetative and reproductive stages of rice cultivation in the Sanjiang Plain of NE China. Samples of overlying water and soil in three layers (0–20, 20–40, and 40–60 cm) were collected before drainage to evaluate variations of DOC and common ions across rice growing stages and to estimate DOC loss by drainage. Sorption experiments were conducted to determine DOC sorption capacities of surface soil (0–5 cm). Compared with the pre-growing stage, DOC concentrations in overlying water and soil significantly increased at the vegetative stage, while significant increases at the reproductive stage were merely in soil. Net movement of DOC was from soil to overlying water at the pre-growing and reproductive stages, and was close to equilibrium at the vegetative stage. Ca2+ and Mg2+ in surface soils (0–20 cm) displayed stronger capacities explaining DOC dynamics in the soil-overlying water system than the other common ions. As Ca2+ and Mg2+ in surface soils (0–20 cm) increased, DOC in the uppermost soil layers (0–20 and 20–40 cm) and overlying water increased, and DOC sorption capacities in surface soil were enhanced. DOC loss from paddy fields by drainage mainly occurred at the vegetative stage, occupying 62–83 % of the total, and much more attention ought to be paid to control drainage DOC loss during this period. In light of important roles of Ca2+ and Mg2+ in DOC dynamics and then DOC loss by drainage, appropriate measures with respect to addition of Ca2+ and Mg2+ could be taken into consideration in rice cultivation to alleviate paddy field DOC export.

The influence of the drainage regime on the installation and the response to vertical cyclic loading of suction caissons in dense sand

Offshore wind turbines are considered as an integral part of renewable energy. Dense sand often characterises the sea bed and suction caisson foundations are increasingly used to support offshore wind turbines at North Sea sites. Significant experience with this technology exists in the oil and gas industry, although these platforms are typically located in deeper water with predominantly clay soils. Therefore, research is required to transfer the existing knowledge. This paper discusses a series of centrifuge tests that investigate the installation and the load transfer mechanisms governing the response of suction caissons embedded in dense sand subjected to vertical cyclic loading. The effect of potential loosening of the internal soil plug during suction installation on the in-service foundation performance is evaluated through cone penetration tests inside the caisson following suction installation at different pumping flow rates. In accompanying tests, the load displacement behaviour in response to vertical cyclic loading is investigated, including significant excursions into tension. The results identify the pore fluid behaviour as the key factor affecting the response, with the pumping flow rate applied during installation being less influential. Based on the findings from the experiments a simplified approach for the prediction of suction caisson behaviour under vertical cyclic loading is presented.

Scalable Ultrahigh-Speed Fabrication of Uniform Polycrystalline Thin Films for Organic Transistors.

The fabrication of organic semiconductor thin films by printing technologies is expected to enable the low-cost production of devices such as flexible display drivers, RF-ID tags, and various chemical/biological sensors. However, large-scale high-speed fabrication of uniform semiconductor thin films with adequate electrical properties for these devices remains a big challenge. Herein, we demonstrate an ultrafast and scalable fabrication of uniform polycrystalline thin films with 100% surface coverage using liquid crystalline semiconductors such as 2-phenyl-7-decyl[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-10) and 2.7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT-C8), at a rate of 3 orders of magnitude higher than before, i.e., 40 mm/s (2.4 m/min) or more by dip-coating in the drainage regime. Organic transistors fabricated with polycrystalline thin films of Ph-BTBT-10 show average mobilities of 4.13 ± 0.75 cm2/(V s) in the bottom-gate-bottom-contact configuration and 10.90 ± 2.40 cm2/(V s) in the bottom-gate-top-contact configuration comparable to those of the devices prepared with single-crystalline thin films. More importantly, these films almost maintain the FET performance when the substrate size is extended up to 4 square inch. The present findings are available for other liquid crystalline semiconductors and bring us one step closer to the realization of printed electronics.

Management of malignant pleural effusions

Malignant pleural effusion (MPE) is a common cause of breathlessness indicative of advanced disease. Treatment approaches focus on relief of breathlessness and optimizing quality of life. A number of recent, high-impact publications give further insight into the advantages of different treatment options. This article provides a summary of the most up-to-date evidence in this area. Recent publications have demonstrated comparable pleurodesis outcomes of talc slurry to talc poudrage and explore strategies to combine the advantages of indwelling pleural catheters (IPCs) with a chemical pleurodesis. A daily IPC drainage regime improves the chances of pleurodesis success and early IPC removal in patients without significant trapped lung. MPE is a diverse condition, with no one strategy representing the 'best' approach for all. Management decisions should be made in conjunction with the patient, taking their views and preferences into consideration.

АНАЛИЗ СИСТЕМЫ «ОСАДКИ-ПОЧВА-ДРЕНАЖ» В УСЛОВИЯХ ИЗМЕНЕНИЯ КЛИМАТА НА СЕВЕРО-ЗАПАДЕ РОССИИ

Purpose: to analyze the soil-climatic and anthropogenic reasons of decreasing drainage efficiency of closed pottery tubular drainage on the reclaimed lands of the North-West of Russia under the observed local weather conditions against the background of global climate changes. Materials and methods. The objects of research are seasonal precipitation regimes, reclaimed lands and drainage systems of closed tubular drainage. The methods of applied mathematical statistics, the ensemble method of processing and generalization of climate forecasts of the Intergovernmental Panel on Climate Change (IPCC), modernized by the authors were used in research. Monitoring data on changes in the physical properties of soils of reclaimed lands during their long-term operation were obtained using laboratory agrophysical methods for studying samples taken in the field. Results. It is shown that under the conditions of the observed climatic changes, the frequency, intensity and extremeness of atmospheric precipitation are increased. Long-term exploitation of lands with a leaching drainage regime is accompanied by changes in the hydrophysical properties of soils, for example, the coefficient of heterogeneity of the subsurface horizons of soils texture of automorphic genesis decreased from 26 to 6. The system “precipitation – soil – drainage” in climatically abnormal weather conditions exceeding the initial calculated precipitation level mode by 10–20 %, is unable to ensure the removal of excess moisture from the root layer. Conclusions: when creating and reconstructing such reclamation drainage systems it is recommended to take into account the tendencies of changes in the spatial-temporal statistical structure of precipitation and to design technologies for regulating the water regime with systems for intercepting and diverting surface runoff on such reclaimed lands.

Suction caisson foundations for offshore wind energy: cyclic response in sand and sand over clay

This technical note considers experimental data on the long-term response of a suction caisson in sand and sand over clay to lateral cyclic loading. Installation of the caisson under suction in a geotechnical centrifuge provides insight into the contribution of this installation process, as well as the effects that soil drainage and consolidation in the clay layer have on the accumulated caisson rotation and change in stiffness. The tests focused on sand over clay, and considered variations in the cyclic load magnitude and symmetry. One-way cyclic loading in sand over clay is seen to result in higher rotation than two-way loading, which contrasts with findings from previous studies in sand. Excess pore pressure dissipation in the clay layer leads to strength increases that stabilise caisson rotation and increase stiffness. The rate of accumulation in caisson rotation is observed to be the same from centrifuge and single gravity tests, while the initial rotation differs with stress level, drainage regime, loading magnitude, soil profile and installation method. The centrifuge tests are considered collectively with equivalent single gravity tests to form a basis for predicting the long-term response of a monopod suction caisson.

Sequence stratigraphic evolution of the syn-rift Early Cretaceous sediments, West Beni Suef Basin, the Western Desert of Egypt with remarks on its hydrocarbon accumulations

The Beni Suef Basin is a petroliferous rift basin straddling the River Nile containing a thick Mesozoic–Paleogene succession. The Kharita Formation is formed in the syn-rift phase of the basin formation and is subdivided into the Lower and Upper Kharita members. These two members are regarded as two third-order depositional sequences (DSQ-1 and DSQ-2). The lowstand systems tract (LST-1) of the DSQ-1 is represented by thick amalgamated sandstone bodies deposited by active braided channels. Mid-Albian tectonic subsidence led to a short-lived marine invasion which produced coastal marine and inner-shelf facies belts during an ensuing transgressive systems tract (TST-1). At the end of the mid-Albian, a phase of tectonic uplift gradually rose the continent creating a fall in relative sea level, resulting in deposition of shallow marine and estuarine facies belts during a highstand systems tract (HST-1). During the Late Albian, a new phase of land-rejuvenation commenced, with a prolonged phase of fluvial depositional. Fluvial deposits consisted of belts of amalgamated, vertically aggraded sandstones interpreted as braided and moderately sinuous channels, in the lower part of the Upper Kharita Member lowstand stage (LST-2). The continuous basin filling, coupled with significant lowering in the surrounding highlands changed the drainage regime into a wide belt of meandering river depositing the transgressive stage (TST-2). The history of the Kharita Formation finalized with a Cenomanian marine transgressive phase. Economically, the TST-1 and HST-1 play a significant role as source rocks for hydrocarbon accumulations, whereas LST-2 act as good reservoir rocks in the Early Cretaceous in the Basin.

The effective mitigation of greenhouse gas emissions from rice paddies without compromising yield by early-season drainage

Global rice production systems face two opposing challenges: the need to increase production to accommodate the world's growing population while simultaneously reducing greenhouse gas (GHG) emissions. Adaptations to drainage regimes are one of the most promising options for methane mitigation in rice production. Whereas several studies have focused on mid-season drainage (MD) to mitigate GHG emissions, early-season drainage (ED) varying in timing and duration has not been extensively studied. However, such ED periods could potentially be very effective since initial available C levels (and thereby the potential for methanogenesis) can be very high in paddy systems with rice straw incorporation. This study tested the effectiveness of seven drainage regimes varying in their timing and duration (combinations of ED and MD) to mitigate CH4 and N2O emissions in a 101-day growth chamber experiment. Emissions were considerably reduced by early-season drainage compared to both conventional continuous flooding (CF) and the MD drainage regime. The results suggest that ED+MD drainage may have the potential to reduce CH4 emissions and yield-scaled GWP by 85–90% compared to CF and by 75–77% compared to MD only. A combination of (short or long) ED drainage and one MD drainage episode was found to be the most effective in mitigating CH4 emissions without negatively affecting yield. In particular, compared with CF, the long early-season drainage treatments LE+SM and LE+LM significantly (p<0.01) decreased yield-scaled GWP by 85% and 87% respectively. This was associated with carbon being stabilised early in the season, thereby reducing available C for methanogenesis. Overall N2O emissions were small and not significantly affected by ED. It is concluded that ED+MD drainage might be an effective low-tech option for small-scale farmers to reduce GHG emissions and save water while maintaining yield.

Assessment of Mid-summer Drainage Regime on the Potential for Sympetrum frequens Conservation by Using Low Threshold Temperature and Total Effective Temperature for Development of Larvae to 10th Instar

Assessment of Mid-summer Drainage Regime on the Potential for <i>Sympetrum frequens</i> Conservation by Using Low Threshold Temperature and Total Effective Temperature for Development of Larvae to 10^th Instar

Crossover from shear-driven to thermally activated drainage of liquid-infused microscale capillaries

The shear-driven drainage of capillary grooves filled with viscous liquid is a dynamic wetting phenomenon relevant to numerous industrial processes and novel lubricant-infused surfaces. Prior work has reported that a finite length $L_\infty$ of the capillary groove can remain indefinitely filled with liquid even when large shear stresses are applied. The mechanism preventing full drainage is attributed to a balance between the shear-driven flow and a counterflow driven by capillary pressures caused by deformation of the free surface. The final equilibrium length $L_\infty$ is uniquely determined by physical properties of the filling liquid as well as the geometry and wettability of the capillary. In this work, we examine closely the approach to the final equilibrium length $L_\infty$ and report a crossover to a slow drainage regime that cannot be described by conventional dynamic models considering solely hydrodynamic and capillary forces. The slow drainage regime observed in experiments can be instead modeled by a kinetic equation describing a sequence of random thermally activated transitions between multiple metastable states caused by surface defects with nanoscale dimensions. Our findings provide new insights on the critical role that natural or engineered surface roughness with nanoscale dimensions can play in the imbibition and drainage of capillaries and other dynamic wetting processes in microscale systems.