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The effect of vertical vibrational loads on the bearing capacity of a foundation resting on salt-encrusted flat soil improved by cement addition was experimentally examined by conducting a physical model. The vibration foundation model resting on the finite dimensions of cemented sabkha was first subjected to incremental vertical monotonic loads to evaluate the bearing capacity for different subsoil conditions; the bearing capacity was calculated from the load–settlement curves. The cemented sabkha overlies the saturated sabkha soil. The influence of the vertical vibrational load for each increment in the vertical monotonic load on the settlement was studied, and a modified load–settlement curve was introduced. For a foundation with no large deformation or liquefaction due to vibrational loads, the vibrational loads insignificantly influence the bearing capacity of the foundation. With increasing frequency, the initial stiffness decreases, resulting in an increase in the settlement. The influence of the cement content and thickness of cemented sabkha on decreasing the foundation's settlement decrease with increasing monotonic loads and operating frequency. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The undrained shear strength of sandy soils during flow failures and liquefaction is a critical metric in the analysis of undrained stability. In our study, the numerical technique known as Artificial Neural Network (ANN) is used for simulating the triaxial stress–strain relationship of sandy soils. This paper aims to predict the undrained shear strength of saturated sandy soil. The proposed program requires simple laboratory soil data to proceed. They are median grain diameter (D50), fines content percentage (FC%), void ratios and relative density. In addition, the stress data of undrained loading such as effective vertical stress (σ'1) and effective horizontal stress (σ'3) are needed. Then, using the program, the deviator stress at yield (qu yield) and, consequently, the yield shear strength of sandy soil (Su (yield)) can be determined. A database of experimental undrained triaxial of saturated sandy soils was collected from the literature and prepared to be the inputs of the network. Two artificial neural networks have been built. By comparing the effectiveness of the two networks, the Back Propagation Neural Network (PBNN) approved higher results and more accuracy than the General Regression Neural Network (GRNN). The computer program, yield shear strength prediction application, written in visual basic, has been developed by the author. For model validation, seven case studies (seven patterns of the production set), which were not seen by the network previously, were presented to the application and the results are compared to the actual output. The produced yield shear strength is very close to the actual strength. [ABSTRACT FROM AUTHOR]

Myricaria laxiflora is an endangered shrub plant with remarkable tolerance to waterlogging stress, however, little attention has been paid to understanding the underlying mechanisms. Here, physiological and transcriptomic approaches were applied to uncover the physiological and molecular reconfigurations in the stem of M. laxiflora in response to waterlogging stress. The accumulation of the contents of H 2 O 2 and malonaldehyde (MDA) alongside increased activities of enzymes for scavenging the reactive oxygen species (ROS) in the stem of M. laxiflora were observed under waterlogging stress. The principal component analysis (PCA) of transcriptomes from five different timepoints uncovered PC1 counted for 17.3 % of total variations and separated the treated and non-treated samples. A total of 8714 genes in the stem of M. laxiflora were identified as differentially expressed genes (DEGs) under waterlogging stress, which could be assigned into two different subgroups with distinct gene expression patterns and biological functions. The DEGs involved in glycolysis were generally upregulated, whereas opposite results were observed for nitrogen uptake and the assimilation pathway. The contents of abscisic acid (ABA) and jasmonic acid (JA) were sharply decreased alongside the decreased mRNA levels of the genes involved in corresponding synthesis pathways upon waterlogging stress. A network centered by eight key transcription factors has been constructed, which uncovered the inhibited cell division processes in the stem of M. laxiflora upon waterlogging stress. Taken together, the obtained results showed that glycolysis, nitrogen metabolism and meristem activities played an important role in the stem of M. laxiflora in response to waterlogging stress. • The ROS scavenging abilities were increased in the stem of Myricaria laxiflora. • The content of ABA and JA in M. laxiflora decreased under waterlogging stress. • The DEGs involved in glycolysis were generally upregulated in M. laxiflora. • Nitrogen metabolism processes were slowed down in response to waterlogging stress. • Transcriptomic network showed the inhibited meristem activities in stem. [ABSTRACT FROM AUTHOR]

Ditch cleaning (DC) is a forestry practice commonly conducted in boreal regions that aim to lower groundwater tables (GWT) in waterlogged soils, thereby maintaining or improving forest growth. However, there is limited information on the impact of DC on water chemistry and dissolved greenhouse gases (GHG) in draining ditch networks. Based on a repeated synoptic sampling of a paired catchment design we here evaluated water chemistry and GHG data in ditch waters from 25 cleaned sites (being cleaned 1–4 years prior to sampling) and 25 non-cleaned reference sites (REF). The sampled sites were further selected to test whether there were any differences in the DC effect if the operations were conducted in forested or clear-cut areas. Across all sites, we found that DC sites exhibited higher pH, sulfate and calcium concentrations than REF sites. Also, lower dissolved carbon dioxide and higher nitrous oxide concentrations were observed in DC sites. In forested areas, DC sites exhibited significantly higher calcium and potassium concentrations, along with reduced levels of methylmercury and carbon dioxide. In clear-cuts, sulfate concentrations were significantly elevated in the DC sites. We suggest that the observed differences in water chemistry and GHG´s between DC and REF sites were induced by the DC and largely driven by lower GWT following DC, resulting in deeper groundwater flow paths through more mineral-rich soil layers, and altered redox conditions. Also, the removal of organic rich sediments and vegetation from the ditches themselves may affect water chemistry and GHG´s e.g. by decreasing the formation of methylmercury and carbon dioxide. • Cleaned and non-cleaned ditches were sampled for water chemistry and GHG's. • pH, sulfate and calcium were higher in cleaned than in non-cleaned ditches. • Cleaned ditches had lower dissolved CO 2 and higher N 2 O than non-cleaned ditches. • MeHg was elevated in cleaned ditches of clear-cuts, but not in forested areas. [ABSTRACT FROM AUTHOR]

The augmented proportion of impervious surfaces and heavy rainfall have resulted in waterlogging, nonpoint source pollution, and environmental degradation. Low impact development (LID) is an effective storm management practice. Based on six different LID paving scenarios, a four objective simulation-optimization framework coupled with stormwater management model (SWMM) and NSGA-Ⅱ that incorporates the ecosystem service value (ESV) was proposed for the optimal layout of LID facilities. A case study in Beijing, China, was taken as an example. The results showed that the rain garden paving scenario is remarkable compared to the other scenarios in realizing ESV, with the dominant ESV of net carbon sinks. The optimization revealed that the change in pollution control rate was more sensitive than the runoff reduction rate. Simultaneously, the optimization of these two indicators will be accompanied by more cost and lower ESV. The optimal solution achieved 32.48 % of runoff reduction rate, 82.22 % of water pollution control rate, 0.73×105 CNY of ESV, and 2.29×106 CNY of cost. The framework provides reference and technical support to achieve the synergistic objectives among cost, water quality and quantity control, and ecosystem services. [Display omitted] [ABSTRACT FROM AUTHOR]

The article discusses the development and use of the Slow Blow controllable backpressure device in plumbing. The device was created to address the problem of blockages in vintage galvanized iron water pipes. It allows compressed air or nitrogen to be introduced into the plumbing system while controlling pressure and flow. The Slow Blow has various benefits, including the ability to remove blockages without excavation, detect leaks more easily, and winterize water piping. The device was developed by Patrick Freeman, the water utilities manager with the City of Fort Smith. [Extracted from the article]

Boreal peatlands are "hotspots" of net methylmercury (MeHg) production and may become drier in the future due to climate change. This study investigates a critical gap by analyzing the nuanced relationship between soil moisture content and the release of MeHg, inorganic mercury (IHg), sulfate (SO 4 2-), and dissolved organic matter (DOM) in a laboratory incubation of boreal peat soils. Dried peat soils exhibited heightened releases of IHg, MeHg, and SO 4 2- during re-wetting events. Both dried and saturated peat soils released more DOM than moist peat soils during re-wetting events, and DOM released from dried soils had higher bioaccessibility than that from the saturated soils (p<0.05). There was an equilibrium of IHg concentrations between peat soils and pore waters, but long-term severe drought may disrupt this equilibrium and then release more IHg to pore waters during re-wetting events. Contrary to expectations, positive relationships between IHg concentrations and SUVA 254 did not exist in all treatments. MeHg and SO 4 2- were depleted quickly because there was no external input of Hg and SO 4 2- to this static system. More bioaccessible DOM than aromatic DOM was released from peat soils with different soil moisture contents after 32 weeks during the re-wetting event (p<0.05). These results imply that re-wetting of peat soils after droughts can increase the release of MeHg from peat soils and may also increase net MeHg production due to the release of SO 4 2- and bioaccessible DOM from peat soils, reshaping our understanding of soil moisture's role in mercury dynamics. This novel insight into soil moisture and MeHg dynamics carries significant implications for mitigating mercury contamination in aquatic ecosystems. [Display omitted] • Boreal peatlands, hotspots of net MeHg production, are becoming drier. • The dry peat released greater concentrations of MeHg after re-wetting. • There was an equilibrium of IHg concentrations between peat soils and pore waters. • However, longer-term drought increased more releases of Hg and bio-accessible DOM. [ABSTRACT FROM AUTHOR]

With woodland expansion providing a nature-based solution to help tackle anthropogenic climate change, the persistence and regeneration of fragmented Atlantic oak woodland is a critical feature of the wilding of uplands and conservation of Temperate Rainforests in Western Europe. Predicted shifts in precipitation with climate change are likely to be a major determinant of tree recruitment here, yet our understanding of the threshold effects of high soil moisture on oak establishment is limited, particularly at early-life-history stages when trees are most vulnerable. We address this gap in knowledge by investigating the effect of soil saturation states on; 1) the capacity for oak seedling development from acorns in peaty soils; and 2) the survival and performance of juvenile (one-year-old) saplings planted in upland pasture. In container experiments, we quantified Quercus robur establishment from acorns in four soil saturation states. There was complete recruitment failure in 'flooded' soils (water level 20 mm above acorn), and reduction (43% survival) at 'high' saturation (water level 81 mm below acorn) compared to 'medium' (77% survival - water level 155 mm below acorn) and 'low' (83% survival - water level 220 mm below acorn) treatments. Surviving seedlings exhibited reduced root:shoot ratio, leaf photosynthesis, and lower likelihood of late season shoot growth in soils of high saturation. In the field experiment, juvenile oak (Q. robur, Q. petraea) saplings were planted in UK upland freely draining, seasonally waterlogged, and waterlogged pastures soils and subject to livestock browsing treatments. Q. robur had greater shoot growth and leaf photosynthesis response to soil saturation than closely related Q. petraea. Results highlight the need for better understanding of soil-dependent influence on tree browsing. We conclude that climate-resilient restoration of Atlantic oak woodland must utilise both European oak species to support seedling and sapling recruitment events in the face of rapid but uncertain changes in precipitation and soil conditions. Such an approach might better allow future natural colonisation events across a gradient of projected soil scenarios and landscape trajectories. Further research should look to better characterise the role of soil moisture on the early-life-history stages of trees. Furthermore, understanding the soil factors that limit seedling and sapling establishment, especially when these factors are themselves perturbed by climate change, is central to both our wider understanding of plant community response to climate change and nature-based solutions to mitigate its effects. [Display omitted] • Inverse response of oak recruitment and Sphagnum growth to soil saturation. • Soil saturation diminished leaf photosynthesis, late growth, and root:shoot ratio. • Q. robur saplings had better performance in saturated upland soils than Q. petraea. • Mixed Quercus planting needed for climate resilient Atlantic oak woodland restoration. • Better understanding of soil-tree interactions to focus wood expansion efforts. [ABSTRACT FROM AUTHOR]

The flow through saturated porous soil is described by Darcy equation that generally has no analytical solution. Therefore, we have to use numerical methods to solve it. There exist several numerical methods and the well-known most used one is the finite elements method. In this work, we use a Diamond finite volumes scheme characterized with its conservation property to simulate Darcy equation in the linear and the non linear case in two dimensional case, based on permeability tensor. Different test cases are studied to validate the accuracy and the efficiency of the numerical model. The numerical scheme proves, through the obtained results, high level of accuracy comparing with the exact solution. The diamond finite volumes scheme for its ability to ensure the mass conservation of our model, knowing that the finite elements or the finite differences methods are less efficient on this side, our finite volumes method is the most suited to the Darcy flow and more faithful to physical problems comparing to other methods. We focused in our study on different aspects of the finite volumes scheme, the mass conservation, the non-linearity of the hydraulic conductivity and their interaction with the finite volumes method. [ABSTRACT FROM AUTHOR]

This 20-month study of a prairie hillslope seep system builds upon and extends the soil moisture record from a previous study conducted during the most extreme drought ever recorded in Texas. We seek to improve understanding of how prolonged drought impacts seep-headwater hydrology, and to determine how well dominant vegetation reflects changes in volumetric soil moisture (θv). Results show the entire hillslope saturates after storm events, but due to severe drought, no surface runoff or channel flow was recorded. We documented changes in soil moisture, with the highest θv occurring along the deeper footslope soils. We hypothesize hyperseasonal environments, or seasonal waterlogging/desiccation of upland vegetation in poorly drained soils, exist in the study area and are the first to quantify hyperseasonality, or % change in magnitude of θv throughout a hydrologic year. The seep and riparian plots aligned with lower hyperseasonality, indicating seasonal hypoxia, but not complete desiccation. High hyperseasonality occurred along the midslope barrens, indicative of a true hyperseasonal environment. We suggest a ≥ 90% threshold would likely indicate true hyperseasonal cyclicity of anaerobic and xeric regimes. Our results provide insight to how extreme drought impacts seep-headwater systems, and how predicted hotter, drier conditions may alter their hydrologic regime. [ABSTRACT FROM AUTHOR]

Copyright of Iheringia. Série Zoologia is the property of Fundacao Zoobotanica do Rio Grande do Sul and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Waterlogging disasters seriously affect residents' lives. Investigating the factors affecting waterlogging is crucial for mitigating waterlogging. Although waterlogging is closely related to land-use patterns, most of the previous studies have analyzed only the impact of urban horizontal patterns on waterlogging at a single scale. Few studies have focused on the role of urban vertical patterns from a multiscale perspective. Therefore, this study investigated the influence of various factors on the density of waterlogging points at grid scales of 1–5 km using Pearson correlation analysis and the random forest model. We conducted a case study for Shenzhen City, and the results show that the building coverage ratio, building crowding degree, building density, proportion of impervious surfaces, proportion of green space, and population density are the most important factors. Moreover, the urban horizontal and vertical patterns have significant scale effects on waterlogging. The influence of horizontal patterns on waterlogging is maximum at a scale of 3 km, while the influence and dominance of the vertical patterns increase with scale. Therefore, controlling building congestion is necessary for alleviating waterlogging, and the rational planning of urban horizontal and vertical patterns is important for the construction of sponge cities. Our results provide decision support for urban land-use optimization and waterlogging mitigation, thereby facilitating sustainable environmental management. • Rational planning of vertical patterns is important for waterlogging mitigation. • We revealed the scale effect of horizontal and vertical patterns on waterlogging. • Influence and dominance of vertical patterns on waterlogging increased with scale. • The most influential factors of waterlogging across various scales were identified. • This study can support waterlogging mitigation and environmental impact assessment. [ABSTRACT FROM AUTHOR]

Altered river hydrology caused by anthropogenic and climatic influences is a global issue causing riparian vegetation species shifts and decline. To help inform efforts to mitigate forest composition shifts through floodplain flow restoration, we tested the first-year responses of three common swamp species, water tupelo (Nyssa aquatica), Ogeechee tupelo (Nyssa ogeche), and pop ash (Fraxinus caroliniana), and two common bottomland hardwood species, overcup oak (Quercus lyrata) and water hickory (Carya aquatica), against twelve moisture treatments through one typical growing season of the Apalachicola River system. Species were grown from seed in a full sun environment under ambient conditions with alteration of soil moisture through treatments varying in timing and duration of ambient precipitation, saturation, or flood. Observations of total emergence, cumulative emergence, total mortality, and final height allowed assessment of responses to treatments and associated stresses. Swamp species emerged quickly early in the growing season compared to bottomland species whose emergence was more gradual. Early-season stresses caused greater mortality of light-seeded swamp species compared to heavier-seeded bottomland species that had ample carbohydrate reserves allowing recovery. Bottomland species were more vulnerable to moisture deficit experienced later in the season. Saturated soil conditions limited the total emergence and rate of emergence of overcup oak. The observed responses to variable stresses can assist forest and restoration managers in developing achievable goals and actions that promote establishment and survival of target species. • Lighter-seeded species emerged more quickly compared to heavier-seeded species. • Emergence rate and total emergence of overcup oak was reduced in saturated soil. • Early season stress significantly impacted mortality of first-year swamp seedlings. • Heavier-seeded bottomland species were more adapted to survive early-season stress. • Saturated soil did not accelerate height growth of swamp species. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Noakhali Pourashava is an important municipality in southern Bangladesh, faces severe waterlogging problems every year during the monsoon period. The present study aimed to investigate the major causes of waterlogging and its negative effects on life, from the viewpoint of people residing in different areas of Noakhali Pourashava, various government, non-government, development organizations as well as various stakeholders including experts. It has been found that Noakhali Pourashava experienced waterlogging during peak monsoon season in ward no. 1, 2, 4, 5, and 8. Most of the inhabitants/respondents of the Noakhali Pourashava claimed that lack of drainage facility; excessive rainfall; inadequate, low capacity and conventional drainage system; natural siltation; improper waste management; absence of proper inlets and outlets; and blockage and encroachment of existing drainage are responsible for waterlogging. It has ascertained that the water logging becomes a burden for the inhabitants of the Pourashava and creating adverse effects on livelihood, society, infrastructure, economy and environment. Other notable adverse effects of waterlogging are disruption of traffic movement and normal life, structures and infrastructure damage and loss of income potentials with a lot of sufferings. The stagnant water acts as a breeding site for the vectors of various diseases and becomes a health hazard to people residing in the waterlogged area. The current study suggests that close coordination among Pourashava authorities, local government agencies and a strong collaboration between public and private sectors as well as local people participation are essential for solving the waterlogging problem effectively and sustainably. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Western Tasmania contains large areas of treeless sedgeland interspersed with scrub and forest vegetation. Why these large treeless areas exist in a region wet enough to support rainforest remains unclear. Slower growth of woody plants in the sedgeland than the scrub and forest could be a factor, because smaller woody plants are more likely to be killed by frequent fire before they mature and set seed. However, there is little information regarding growth rates of woody plants in these communities. We characterised soils and compared growth rates of small woody plants in sedgeland, scrub and forest at two sites using diverse approaches: (i) field observational studies of seedlings from a broad range of species that established following a wildfire in 2019 at site 1; (ii) a dendrochronological study of mature myrtaceous shrubs that had established following a fire in 1983 and were killed by the 2019 fire at site 1 (iii) a field experiment in which fertiliser was applied to transplanted seedlings of the myrtaceous shrub Leptospermum scoparium at site 2. (iv) We also used a glasshouse experiment to test the effects of nutrients and waterlogging on L. scoparium seedlings. Sedgeland soils were organic and poorly drained, whereas forest soils were mineral and well drained; scrub soils were organic at the surface but well drained. Concentrations of most soil nutrients, including total P, K, Ca, Mg and Mn were highest in the forest, although N was highest in sedgeland. At both sites, woody plant species grew faster in scrub and forest than in sedgeland, by a factor of 1.7–3.4. When fertiliser was added to transplanted L. scoparium seedlings, there was no difference in growth between sedgeland and scrub. In the glasshouse experiment, growth was limited by both low soil nutrients and waterlogging. However, the waterlogging effect was not apparent in the field experiment because conditions were dry. Our study shows slow growth of woody plants in Tasmanian sedgelands associated with infertile and waterlogged organic soils. Fire disturbance sharpens the boundary but is not the cause of it. • Tasmania contains areas of treeless sedgeland interspersed with forest and scrub. • An unproven hypothesis is that tree growth is slower in sedgeland. • We conducted observational and experimental growth studies in field and glasshouse. • All studies showed slower tree growth in sedgeland than scrub or forest. • Edaphic factors (low nutrients and waterlogging) can explain slower tree growth. [ABSTRACT FROM AUTHOR]

Improving our understanding of how different tree species function in urban stormwater management systems is important, as tree pits may provide a temporary reservoir for stormwater and as trees have the potential to actively reduce stormwater runoff by transpiration. While urban tree planting pits are increasingly used for short-term water storage during stormwater runoff events, this storage can have negative effects on both tree vitality and water removal capacity, since stress from waterlogging result in stomatal closure. However, sensitivity to water stress varies by species. It is therefore important to determine which tree species can maintain long-term vitality and continued transpiration even under water stress, and thus are suitable for such locations. Here, we studied how nine different tree species, varying in expected tolerance to water stress, were affected by short-term and seasonal waterlogging, in a greenhouse experiment. The seedlings (Magnolia x loebneri , Tilia tomentosa , and Sorbus torminalis – low water logging tolerance; Cercidiphyllum japonicum , Rhamnus cathartica , and Fraxinus ornus – medium water logging tolerance; Quercus palustris , Acer saccharinum , and Fraxinus pennsylvanica – high water logging tolerance) were exposed to two days, five days and seasonal waterlogging. The treatments reflected best practice (optimal), suboptimal and total lack of tree pit drainage, using Swedish standards. Stomatal conductance and leaf water potential were determined regularly over a period of 71 days, and morphological adjustments were registered. Four of the species were affected already after two days of waterlogging, with reduced stomatal conductance either during the waterlogging or immediately after, and only the most waterlogging tolerant species were unaffected by the five-day treatment. However, all plants survived waterlogging for almost 30 days before the estimated permanent wilting was reached in some plants. We suggest that tree species selection for stormwater management systems should consider the species' capacity to maintain high stomatal conductance during waterlogging, as there were clear differences between species. The effectiveness of the selected species could have an important impact on the stormwater management capacity of cities, as well as on other aspects of ecosystem service delivery from urban trees. [ABSTRACT FROM AUTHOR]

The urban forest is important for ecosystem service provision such as rainfall interception, pollution reduction, and biodiversity value. These provide health and wellbeing benefits to people living in urban areas and, with climate change projected to increase extreme weather, the importance of urban trees is likely to increase whilst at the same time putting the urban forest at increasing risk. The urban forest is composed of trees in both public and private ownership. How this ownership status impacts the characteristics of urban forests in Great Britain such as structure, composition, and health is not well known. We used a large database of 18,632 trees to compare the private (10,300 trees) and public (8332 trees) elements of 19 urban forests in Great Britain. We show that trees in the private urban forest are, for a given trunk diameter, 20% shorter and have an 18% smaller crown area. The private urban forest has a 9% lower tolerance for waterlogging stress; however, is 40–57% more diverse across taxonomic levels, hosts double the number of non-native species, and has 6% better tree condition. Management of the urban forest to reduce tree height and crown area reduces the provision of many regulatory ecosystem services. However, the better health and diversity of the private urban forest likely bolsters resilience to climate change and novel pests and diseases, indicating the importance for strategy and policy to recognise and work with those who own and manage private urban trees. [ABSTRACT FROM AUTHOR]

In past earthquake disasters, numerous building structure piles were damaged due to soil liquefaction occurring during the earthquake. Damage to these piles, because they are underground, is difficult to find. The authors aim to develop a monitoring method for pile damage based on superstructure dynamic response. This paper investigated the basic relationship between the damage of large cross section cementitious piles and the dynamic response of the super structure using a centrifuge test apparatus. A dynamically excited specimen used simple cross section pile models consisting of aluminum rod and mortar, saturated soil (Toyoura sand) of a relative density of 40% and a super-structure model of a natural period of 0.63 s. In the shaking table test under a 50G field, excitation was a total of 3 Rinkai waves at different amplitudes. The maximum acceleration of each of the excitations was 602, 336 and 299 gal. The centrifuge test demonstrated the liquefaction of saturated soil and the failure behavior of piles. In the test results, the damage to the piles affected the predominant period of acceleration response spectrum on the footing of the superstructure. [ABSTRACT FROM AUTHOR]

To better understand the Sb phytoavailability in rice, we studied Sb accumulation in rice (Zhongjiazao-17, widely cultivated in Hunan province) at different growth stages based on adding SbIII and SbV to waterlogged soils in 10, 50 and 100 mg kg−1 treatment levels. Proportional exogenous SbIII and SbV remained in the soil solution after equilibration. In SbIII treatments, the iron plaque (IP) amounts and Sb in rice roots sharply increased from tillering to jointing stages and then reduced at the following stages. However, in SbV treatments, they increased continuously from tillering to maturing stages. The accumulation trends of Sb in straws, ears and grains were consistent in SbIII and SbV treatments, rising from tillering to jointing stages followed with reducing from jointing to flowering stages slightly, and rising again significantly from flowering to maturing stages. The Tfsoil-grain values in all the Sb treatments were low (0.77 × 10−3-5.1 × 10−3), However, when Sb in waterlogged soils were higher than 50 mg kg−1, it could pose human health risk for residents. Image 1 • Jointing stage is critical for Sb uptake in SbIII treatment. • Flowering stage is critical for Sb uptake in SbV treatment. • Rice straw accumulated the highest concentration of Sb at maturing stage. • Transfer ability of Sb decreased with increasing Sb treatment level. • More than 50 mg kg−1 of Sb in soils is risky for residents. Proportional of SbIII and SbV still remained in soil solutions; The Sb accumulation trends at different rice growth stages were various. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Waterlogging has been shown to have a significant inhibitory effect on plant growth. However, the response mechanisms of the soil environment of sugar beet seedlings under waterlogging conditions still need to be fully understood. This study aimed to investigate the effects of waterlogging treatments on the content of effective nutrients and the microbial communities in the rhizosphere and non-rhizosphere using high-throughput sequencing. We set up waterlogging and non-waterlogging treatments, sampled sugar beet seedlings after 10 days of waterlogging, determined the effective soil nutrients in the rhizosphere and non-rhizosphere of the plants, and analyzed the differences in microbial diversity at ten days of waterlogging. The results showed that waterlogging significantly affected available potassium (AK) content. The Ak content of waterlogged soil was significantly higher than that of non-waterlogged soil. Waterlogging caused no significant difference in available nitrogen (AN) content and pH. Moreover, the plant growth-promoting bacteria Pseudomonas was significantly enriched in sugar beet waterlogged rhizospheres compared with the non-waterlogged ones. Similarly, the harmful fungi Gibellulopsis and Alternaria were enriched in sugar beet non-waterlogged rhizosphere. The network analysis revealed that waterlogging built a less complex root-microbial network than non-waterlogging. These findings implied that sugar beets subjected to waterlogging stress were enriched with beneficial microorganisms in the rhizosphere, potentially alleviating the stress. [Display omitted] • Potential beneficial bacteria enrichment in the rhizosphere of sugar beet under waterlogging stress. • Significant changes in rhizosphere microbial community diversity of sugar beet under waterlogging stress. • Network analysis revealed that waterlogging built a less complex root-microbial network than non-waterlogging. • Significant changes in soil physicochemical properties under waterlogging stress. [ABSTRACT FROM AUTHOR]

Cities around the world are embracing stormwater control measures (SCMs) to reduce the environmental damage caused by impervious runoff. At the same time, there is a push to increase tree canopy cover to green neighborhoods and mitigate urban heat. Establishing SCMs that include trees may achieve these two objectives, but it is important to understand which design characteristics promote or reduce tree health and growth. We therefore undertook an 18-month streetscape experiment comparing four tree pit SCM designs, along with a control (non-SCM) street tree planting, to identify design characteristics influencing the water balance and growth of newly planted trees ( Acer campestre (L.)) in an established urban area dominated by clay soils. Trees in pits with an underdrain showed double the growth of conventionally planted street trees receiving no stormwater. However, the low exfiltration rates of some non-drained tree pits resulted in some tree pits experiencing waterlogging and subsequent poor tree growth or even death. In other non-drained tree pits, the heterogeneity of urban soils resulted in sufficiently high exfiltration rates to avoid waterlogging and promote increased tree growth, even in these heavy clay soils. Our results suggest that establishing tree growth can be substantially increased by directing stormwater into tree pits, however, waterlogging conditions should be avoided via an underdrain or limiting installation to soils with a sufficiently high exfiltration rate. [ABSTRACT FROM AUTHOR]

Shooting ranges polluted by antimony (Sb), lead (Pb), copper (Cu) and zinc (Zn) are used for animal grazing, thus pose a risk of contaminants entering the food chain. Many of these sites are subject to waterlogging of poorly drained soils. Using field lysimeter experiments, we compared Sb, Pb, Cu and Zn uptake by four common pasture plant species ( Lolium perenne , Trifolium repens , Plantago lanceolata and Rumex obtusifolius ) growing on a calcareous shooting range soil under waterlogged and drained conditions. To monitor seasonal trends, the same plants were collected at three times over the growing season. Additionally, variations in soil solution concentrations were monitored at three depths over the experiment. Under reducing conditions, soluble Sb concentrations dropped from ∼50 μg L −1 to ∼10 μg L −1 , which was attributed to the reduction of Sb(V) to Sb(III) and the higher retention of the trivalent species by the soil matrix. Shoot Sb concentrations differed by a factor of 60 between plant species, but remained at levels <0.3 μg g −1 . Despite the difference in soil solution concentrations between treatments, total Sb accumulation in shoots for plants collected on the waterlogged soil did not change, suggesting that Sb(III) was much more available for plant uptake than Sb(V), as only 10% of the total Sb was present as Sb(III). In contrast to Sb, Pb, Cu and Zn soil solution concentrations remained unaffected by waterlogging, and shoot concentrations were significantly higher in the drained treatment for many plant species. Although showing an increasing trend over the season, shoot metal concentrations generally remained below regulatory values for fodder plants (40 μg g −1  Pb, 150 μg g −1 Zn, 15–35 μg g −1 Cu), indicating a low risk of contaminant transfer into the food chain under both oxic and anoxic conditions for the type of shooting range soil investigated in this study. [ABSTRACT FROM AUTHOR]

Glycine betaine (GB) is an important organic compound mediating plant responses to environmental stresses. However, despite ample research on this biomolecule, the potential of GB in mitigating the effects of waterlogging in plants has not been established. Therefore, we studied the influence of GB on growth and physiology of tomato plants under waterlogged conditions. Waterlogging reduced plant growth, degraded chlorophyll, and increased concentration of malondialdehyde and hydrogen peroxide that deteriorated membrane integrity. Waterlogging increased catalase and peroxidase activities. Waterlogging increased the concentration of Na and reduced concentrations of K. Reductions in root Ca were also recorded. GB enhanced growth, concentration of chlorophyll and activities of superoxide dismutase, catalase, and peroxidase that in turn protected the plants from oxidative damage. GB decreased Na while increasing leaf and root K and stem and fruit Ca under waterlogging. Waterlogging reduced fruit quality. There was decrease in protein, fat, and total dissolved solids and an increase in fruit moisture, P, and Na in plants under waterlogging. GB enhanced fruit quality largely by improving fruit protein, ash, fat, TDS, and Ca, while it decreased fruit Na. The results of this study suggest the use of GB for commercial production of tomato where waterlogging is likely. [ABSTRACT FROM AUTHOR]

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Tidal flat elevation in the estuarine wetland determines the tidal flooding time and flooding frequency, which will inevitably affect the formation of iron plaque and accumulations of heavy metals (HMs) in wetland plants. The present study investigated the formation of iron plaque and HM's (copper, zinc, lead, and chromium) accumulation in S. alterniflora , a typical estuarine wetland species, at different tidal flat elevations (low, middle and high) in filed and at different time (3, 6, 9, 12 h per day) of waterlogging treatment in greenhouse conditions. Results showed that the accumulation of copper, zinc, lead, and chromium in S. alterniflora was proportional to the exchangeable fraction of these metals in the sediments, which generally increased with the increase of waterlogging time, whereas the formations of iron plaque in roots decreased with the increase of waterlogging time. Under field conditions, the uptake of copper and zinc in the different parts of the plants generally increased with the tidal levels despite the decrease in the metals’ exchangeable fraction with increasing tidal levels. The formation of iron plaque was found to be highest in the middle tidal positions and significantly lower in low and high tidal positions. Longer waterlogging time increased the metals’ accumulation but decreased the formation of iron plaque in S. alterniflora . The binding of metal ions on iron plaque helped impede the uptake and accumulation of copper and chromium in S. alterniflora . [ABSTRACT FROM AUTHOR]

Palaeoecological and geoarchaeological investigations which cover the Anglo-Saxon period are rare, particularly in chalk downland landscapes which are considered to have limited palaeoenvironmental potential. The present study explores a sequence which can be directly related to the occupation history of the major Anglo-Saxon settlement at Lyminge, Kent. This work demonstrated a sequence of palaeochannels and organic deposits associated with the latter part of an archaeological sequence which spans the 5th to the 11th centuries AD. A range of evidence for the environment and economic activity is presented which suggests landscape continuity, possibly stretching back as far as the Romano-British period. The sequence revealed worked wood and evidence for livestock management and cereal cultivation, some of which is contemporary with the final phases of occupation of a 7th century ‘great hall complex’ and its subsequent transformation into a royal monastery. Agricultural activity following the abandonment of the pre-monastic settlement area caused this stream margin to become gradually buried by ploughwash which displaced the channel over time and sealed the organic deposits. It is incredibly rare to find such organic preservation in direct association with an Anglo-Saxon downland rural settlement and this is the first time that such a sequence has been analysed in association with the latter phases of a known Anglo-Saxon royal and monastic centre. [ABSTRACT FROM AUTHOR]

The rapid expansion of construction related to coastal development evokes great concern about environmental risks. Recent attention has been focused mainly on factors related to the effects of waterlogging, but there is urgent need to address the potential hazard caused by artificial topography: derived changes in the elemental composition of the sediments. To reveal possible mechanisms and to assess the environmental risks of artificial topography on transition of elemental composition in the sediment at adjoining zones, a nest-random effects-combined investigation was carried out around a semi-open seawall. The results implied great changes induced by artificial topography. Not only did artificial topography alter the sediment elemental composition at sites under the effect of artificial topography, but also caused a coupling pattern transition of elements S and Cd. The biogeochemical processes associated with S were also important, as suggested by cluster analysis. The geo-accumulation index shows that artificial topography triggered the accumulation of C, N, S, Cu, Fe, Mn, Zn, Ni, Cr, Pb, As and Cd, and increased the pollution risk of C, N, S, Cu, As and Cd. Enrichment factors reveal that artificial topography is a new type of human-activity-derived Cu contamination. The heavy metal Cu was notably promoted on both the geo-accumulation index and the enrichment factor under the influence of artificial topography. Further analysis showed that the Cu content in the sediment could be fitted using equations for Al and organic carbon, which represented clay mineral sedimentation and organic matter accumulation, respectively. Copper could be a reliable indicator of environmental degradation caused by artificial topography. [ABSTRACT FROM AUTHOR]

Bangladesh has often been considered as the land of extremes in terms of natural processes. The statement is justified by the presence of world’s largest delta, one of the largest river systems carrying a huge amount of water and sediment discharge as well as prevalence of a number of natural hazards. These characteristics make the region very dynamic and sensitive to changes. Bangladesh is one of the most densely populated countries in the world and human development activities to accommodate the large population have caused major disruptions to the dynamics of the natural system. The study focuses on such a case where anthropogenic activities, such as polderization, dam construction etc. have disrupted the natural land building process and have caused persistent waterlogging in the southwest region of Bangladesh. The rivers in the region are naturally characterized by active deposition of sediment in riverbed causing reduced drainage capacity. Moreover, construction of coastal polders that de-linked the flood plains from the rivers, and diminished upstream flow during the dry season deteriorated the sedimentation problem in the region. The study delineates different hydrological parameters and characteristics of the deposited sediments along with identification of social vulnerabilities. The investigated hydrological and sedimentological characteristics refer to the existing sediment management as well as provide a framework for the future development works in the pre-identified TRM sites. Based on the findings, the suitability of Inclusive and Adaptive Tidal River Management (TRM++) technique was assessed. [ABSTRACT FROM AUTHOR]

This study aims to assess the role of Fe plaque in metal uptake and translocation by different wetland plants and examine the effects of organic acids on metal detoxification in wetland plants. It was found that although exposed to a similar level of metals in rhizosphere soil solution, metal uptake by shoots of Cypercus flabelliformis and Panicum paludosum was greatly reduced, consequently leading to a better growth under flooded than under drained conditions. This may be related to the enhanced Fe plaque in the former, but due to the decreased root permeability in the latter under anoxic conditions. The Fe plaque on root surface has potential to sequester metals and then reduce metal concentrations and translocation in shoot tissues. However, whether the Fe plaque acts as a barrier to metal uptake and translocation may also be dependent on the root anatomy. Although metal tolerance in wetland plants mainly depends upon their metal exclusion ability, the higher-than-toxic-level of metal concentrations in some species indicates that internal metal detoxification might also exist. It was suggested that malic or citric acid in shoots of P. paludosum and C. flabelliformis may account for their internal detoxification for Zn. [ABSTRACT FROM AUTHOR]

• A greener cementitious composite was produced with ground jet grouting waste. • The new cement composite showed desired fresh and hardened properties. • Adding ground jet grouting waste promoted the cement hydration. • The recycling of ground jet grouting waste reduced the environmental footprints. Jet grouting waste (JGW), a cement-soil mixture, represents a significant solid waste stream from soil consolidation activities. The current disposal of JGW at landfills posed a significant environmental issue in countries with limited land space. In this research, JGW was ground into powders without further special treatment and then used as a cementitious material. The properties of cement-based materials incorporating JGW powders were evaluated in terms of the setting time, rheological behaviors, hydration products, pore structures, and compressive strength. The results showed that JGW powder had cementitious properties and could enhance the hydration rate and degree of cement clinker phases. The specimens with up to 20% JGW exhibited similar rheological properties, pore structures, and compressive strength to the control specimen. The embodied energy and CO 2 emissions of the cement mortar decreased linearly with the increasing JGW dosage, supporting the use of JGW to develop greener cement-based materials. [Display omitted] [ABSTRACT FROM AUTHOR]

• Minority tree species are essential for many ecosystem services but often overlooked. • Waterlogging can be a more severe stressor then drought for many Prunus species. • Strategies to handle drought and waterlogging differs between Prunus species. Fruit-bearing and flowering minority tree species, such as many species from the Prunus genus, are essential for multiple ecosystem services in the landscape. Although common, but never dominating, these minority species are often overlooked compared to commercial timber trees in relation to climate change. Induced stress on trees through climate change in central Europe will not only be caused by drought but also by extreme precipitation and pluvial flooding. This study experimentally address this by testing both waterlogging and drought tolerance in three key species of Prunus for central Europe that naturally span a wide variation of habitat conditions. The selected species Prunus mahaleb , Prunus avium and Prunus padus were subjected to both drought and waterlogging in a greenhouse experiment. Plant functionality in the form of midday leaf water potential, stomatal conductance and turgor loss point together with different aspects of biomass allocation and growth was tested. All included species lost their stomatal conductance and leaf water potential within a few days in the waterlogging treatment. Only P. padus had the capacity to recover with new leaves after the waterlogging ended, suggesting that avoidance strategies though leaf shedding can be a complementary mechanism to withstand waterlogging. P. padus kept its stomatal conductance and water potential for the longest time in the drought treatment followed by P. mahaleb and P.avium. This longevity in the drought treatment for P. padus could be explained by both tolerance strategies through lower turgor loss point, but also avoidance strategies with fast changes in growth and higher allocation of biomass to the roots. There is a clear risk that ecosystem service from Prunus species in the landscape can be negatively affected not only by drought but also by increased events of waterlogging. This highlights the need for including minority species and also other climate stressors in addition to drought in the planning and management of multifunctional landscapes. [ABSTRACT FROM AUTHOR]

Due to both natural and anthropogenic forces, the south west part of the Ganges-Brahmaputra coastal area is facing diverse problems such as waterlogging, salinity, and loss of biodiversity. In order to address these challenges, local people have identified ‘tidal river management (TRM)’ as a comprehensive approach for sustainably managing this part of the Ganges-Brahmaputra Basin. However, due to institutional limitations, mismanagement and social conflicts, application of the TRM approach is not straightforward. In order to identify existing implementation barriers and to effectively apply the TRM approach, a transdisciplinary approach is examined for its potential to inform the re-shaping of TRM governing values and actions. It is argued that a thorough application of a transdisciplinary framework is essential, supported by the active involvement of key agencies and local stakeholders. The proposed transdisciplinary framework can potentially be applied to TRM projects for solving waterlogging and associated problems in order to achieve greater sustainability of the area. [ABSTRACT FROM AUTHOR]

The paper is devoted to the construction of various earth and engineering structures being operated on soft soils in the northern regions of Russia with a pronounced continental climate and a lot of wetlands. The problem of year-round cooling of water-saturated soil to freezing temperatures in order to convert it into a frozen state of permafrost is considered. To convert the soil into a frozen state of permafrost and keep the state all year around, including the summer period, the new soil cooling apparatus has been developed. The apparatus is economical; it has no moving parts and can operate for a long time without involving any staff. [ABSTRACT FROM AUTHOR]

Batch and saturated soil column experiments were conducted to investigate sorption and mobility of two 14 C-labeled contaminants, the hydrophobic chlordecone (CLD) and the sulfadiazine (SDZ), in the absence or presence of functionalized multi-walled carbon nanotubes (MWCNTs). The transport behaviors of CLD, SDZ, and MWCNTs were studied at environmentally relevant concentrations (0.1–10 mg L −1 ) and they were applied in the column studies at different times. The breakthrough curves and retention profiles were simulated using a numerical model that accounted for the advective-dispersive transport of all compounds, attachment/detachment of MWCNTs, equilibrium and kinetic sorption of contaminants, and co-transport of contaminants with MWCNTs. The experimental results indicated that the presence of mobile MWCNTs facilitated remobilization of previously deposited CLD and its co-transport into deeper soil layers, while retained MWCNTs enhanced SDZ deposition in the topsoil layers due to the increased adsorption capacity of the soil. The modeling results then demonstrated that the mobility of engineered nanoparticles (ENPs) in the environment and the high affinity and entrapment of contaminants to ENPs were the main reasons for ENP-facilitated contaminant transport. On the other hand, immobile MWCNTs had a less significant impact on the contaminant transport, even though they were still able to enhance the adsorption capacity of the soil. [ABSTRACT FROM AUTHOR]