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Denitrification is a key process buffering the environmental impacts of agricultural nitrate loads but, at present, remains the least understood and poorly quantified sink in nitrogen budgets at the watershed scale. The present work deals with a comprehensive and detailed analysis of nitrogen sources and sinks in the Burana–Volano–Navigabile basin, the southernmost portion of the Po River valley (Northern Italy), an intensively cultivated (> 85% of basin surface) low-lying landscape. Agricultural census data, extensive monitoring of surface–groundwater interactions, and laboratory experiments targeting N fluxes and pools were combined to provide reliable estimates of soil denitrification at the basin scale. In the agricultural soils of the basin, nitrogen inputs exceeded outputs by nearly 40% (~ 80 kg N ha−1 year−1), but this condition of potential N excess did not translate into widespread nitrate pollution. The general scarcity of inorganic nitrogen species in groundwater and soils indicated limited leakage and storage. Multiple pieces of evidence supported that soil denitrification was the process that needed to be introduced in the budget to explain the fate of the missing nitrogen. Denitrification was likely boosted in the soils of the studied basin, prone to waterlogged conditions and consequently oxygen-limited, owing to peculiar features such as fine texture, low hydraulic conductivity, and shallow water table. The present study highlighted the substantial contribution of soil denitrification to balancing nitrogen inputs and outputs in agricultural lowland basins, a paramount ecosystem function preventing eutrophication phenomena.

Solar power development over canals is an emerging response to the energy–water–food nexus that can result in multiple benefits for water and energy infrastructure. Case studies of over-canal solar photovoltaic arrays have demonstrated enhanced photovoltaic performance due to the cooler microclimate next to the canal. In addition, shade from the photovoltaic panels has been shown to mitigate evaporation and potentially mitigate aquatic weed growth. However, the evaporation savings and financial co-benefits have not been quantified across major canal systems. Here we use regional hydrologic and techno-economic simulations of solar photovoltaic panels covering California’s 6,350 km canal network, which is the world’s largest conveyance system and covers a wide range of climates, insolation rates and water costs. We find that over-canal solar could reduce annual evaporation by an average of 39 ± 12 thousand m3 per km of canal. Furthermore, the financial benefits from shading the canals outweigh the added costs of the cable-support structures required to span the canals. The net present value of over-canal solar exceeds conventional overground solar by 20–50%, challenging the convention of leaving canals uncovered and calling into question our understanding of the most economic locations for solar power. Over-canal solar photovoltaic arrays are likely to reduce water evaporation and carry financial co-benefits, but estimates are lacking. With hydrologic and techno-economic simulations of solar panels covering California’s canal network, this study shows the advantages of covering canals with solar panels.

The paper presents the floristic diversity of the left bank of the Danube and the canal network of Krnjaca and Borca settlements, as well as the factors that endanger it. 216 autochthonous and allochthonous plant species were recorded in the investigated area. A large number of invasive plant species have been observed that spread rapidly and easily forming stable populations that displace native plants. Some of them are: Amorpha fruticosa L., Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle, Asclepias syriaca L., Ambrosia artemisiifolia L. and others. The presence of 6 species that are rare and endangered in Serbia is especially significant, as well as 5 relict species. During the investigation, the factors which influence on natural habitats degradation and the reduction of autochthonous floristic diversity were identified. Accordingly, measures for protection and preservation of autochthonous floristic diversity are recommended.

We assess the impact of access to Bangkok’s nineteenth-century canal network on orchard productivity using a new dataset constructed from 1880s orchard land deeds. We find that properties located adjacent to canals, which were built for purposes exogenous to orchard production, had significantly higher labor productivity than those located inland. Gaining direct access to canals led to productivity improvements through better access to markets, which in turn enhanced cultivators’ welfare. We conclude, based on a method developed by Oster (2019), that unobserved selection bias is negligible, allowing for the positive impact of canal access to be interpreted as causal.

Considering the increasing incidence of allergy symptoms in Europe in the past decades, it is useful to obtain precise ecological and biological data regarding the allergenic plants. This study was conducted in order to assess habitat conditions allowing the development of allergenic plants along the Danube-Tisza-Danube canal network (Banat region, Serbia). In this regard, the distribution of these plants and the relationships among their eco-biological characteristics were studied. The results represent the one step further in the assessment of the habitat conditions allowing the development of allergenic plants in the study area. Twenty four allergenic plants were found, with a predominance of wetland plants (37.50%) and geophytes (41.67%). Correlation and PCA analyses determined that the flowering time of allergenic plants is correlated with the ecological group, life form and habitat conditions (aeration, pH, humus content, moisture, and continentality). The unfavorable periods for allergy sufferers are early spring and summer. Pollen-allergenic forest phanerophytes flowered early, had the shortest flowering period, and inhabited neutral to alkaline soil with less humus content, compared to the wetland and weed-ruderal allergenic plants. Habitat moisture reduced soil aeration and modified the effects of the continental climate, favoring the development of numerous allergenic species along the canals. Most of the identified allergenic species are invasive in Europe. Moreover, these species are frequently grown in urban green areas. Therefore, the avoidance of excessive use of these allergenic species in urban ecosystems may provide healthier environments for allergy sufferers and contribute to the preservation of the native flora biodiversity.

This paper examines mobility governance in an environment where varied mobility practices occur. Drawing on a quasi-ethnography of canal users in England and Wales, we discuss how multiple mobilities (including boating, walking, cycling and running) are practised in the relatively confined and linear spaces of canals and adjacent towpaths, and often at the same time. We demonstrate how these different yet intertwined modes of movement, and their associated tempos, are governed through creative interplays of freedom and control, and hierarchy and etiquette. These findings give rise to wider questions regarding the potentialities of governmobility – i.e. a system in which mobilities are able to govern themselves. Our conclusion, therefore, explores how the governance of mobilities on the UK canal network might offer insight, or a ‘watery blueprint’, for mobility governance in other shared spaces. This includes exploring the debates between giving citizens greater freedom and agency to negotiate their own mobility juxtapositions and tensions, versus imposing upon them stricter rule-based systems of mobility regulation.

Bats are the only mammals to have achieved powered flight. A key innovation allowing for bats to conquer the skies was a forelimb modified into a flexible wing. The wing bones of bats are exceptionally long and dynamically bend with wingbeats. Bone microarchitectural features supporting these novel performance attributes are still largely unknown. The humeri and femora of bats are typically avascular, except for large-bodied taxa (e.g., pteropodid flying foxes). No thorough investigation of vascular canal regionalization and morphology has been undertaken as historically it has been difficult to reconstruct the 3D architecture of these canals. This study augments our understanding of the vascular networks supporting the bone matrix of a sample of bats (n = 24) of variable body mass, representing three families (Pteropodidae [large-bodied, species = 6], Phyllostomidae [medium-bodied, species = 2], and Molossidae [medium-bodied, species = 1]). We employed Synchrotron Radiation-based micro-Computed Tomography (SRμCT) to allow for a detailed comparison of canal morphology within humeri and femora. Results indicate that across selected bats, canal number per unit volume is similar independent of body size. Differences in canal morphometry based on body size and bone type appear primarily related to a broader distribution of the canal network as cortical volume increases. Heavier bats display a relatively rich vascular network of mostly longitudinally-oriented canals that are localized mainly to the mid-cortical and endosteal bone envelopes. Taken together, our results suggest that relative vascularity of the limb bones of heavier bats forms support for nutrient exchange in a regional pattern.

Bones are one of the most common vertebrate fossil remains and are widely used as proxy archives in palaeontology and archaeology. Previous histological analyses have shown that bone microarchitecture is mostly well-preserved in fossil remains, but partially or even entirely lost in most archaeological specimens. As a consequence, processes occurring during early diagenesis are pivotal for the preservation of bones and a better understanding of these processes would be required to assess the significance of information stored in fossilized bones. Although much of the changes occur at the nanometer scale, determining the resistance of bone microarchitecture to diagenetic alteration on a microscopic scale constitutes a prerequisite for more detailed studies. Here, results from the first comparative in vitro taphonomy study of cortical bone simulating conditions potentially encountered in early diagenetic settings are presented. In order to accelerate anticipated early diagenetic changes and to facilitate their study in a practical framework, cortical bone samples were exposed to aqueous solutions with temperature, time, and composition of the experimental solutions as controlled parameters. Before and after the experiments, all samples were characterized quantitatively using micro-computed tomography to document structural changes. The results show that the overall change in cortical porosity predominantly occurred in canals with diameters ≤9 µm (∆Ct.Po = ±30%). Furthermore, the data also show that the solution composition had a stronger impact on changes observed than either temperature or time. It was also found that samples from the two experimental series with a freshwater-like solution composition showed a characteristic reaction rim. However, it remains unclear at present if the observed changes have an impact on reactions occurring at the nanometer scale. Nonetheless, the results clearly demonstrate that on a micrometer scale down to 3 μm, bone microarchitecture is largely resistant to aqueous alteration, even under very different physicochemical conditions. In addition, the data illustrate the complexity of the interaction of different diagenetic factors. The results presented here provide a solid framework for future investigations on reaction and transport mechanisms occurring during the early diagenesis of fossil bones.

The liver fluke Opisthorchis viverrini s.l. is associated with a long-term public health problem in Thailand. However, O. viverrini s.l. infection in Bithynia snails in the canal network system (CNS) in the Bangkok Metropolitan Region (BMR) has never been assessed. This study aimed to investigate the occurrence of B. siamensis siamensis and the prevalence of O. viverrini s.l. infection in this snail in the CNS in BMR along with morphological examination and molecular analyses on O. viverrini s.l. cercariae. The snails were randomly sampled from the CNS in all BMR areas from January 2018 to July 2019. Snail specimens were identified and examined for digenean infection by shedding and dissection. The cercariae were identified using morphology and molecular methods, including PCR with a species-specific primer and a Bayesian phylogenetic analysis of ITS2 sequences. Bithynia siamensis siamensis was found in almost all sampling localities, with different quantities and detected frequencies. From a total of 7473 B. s. siamensis specimens, O. viverrini s.l. infections were detected in the Northern Bangkok, Muang Nakhon Pathom, Krathum Baen, and Lam Luk Ka areas with an overall prevalence of 0.05% (4/7473) and prevalence of 0.22% (1/455), 0.21% (1/469), 0.40% (1/253), and 0.16% (1/614) in individual localities with positive snails, respectively. This study is the first investigation of digenean infection in the canal network system-type habitat in Thailand and revealed extremely low O. viverrini s.l. prevalence.Très faible prévalence des cercaires d’Opisthorchis viverrini s.l. chez les mollusques Bithynia siamensis siamensis du réseau de canaux dans la région métropolitaine de Bangkok, Thaïlande.La douve du foie Opisthorchis viverrini s.l. cause un problème de santé publique récurrent en Thaïlande. L’infection des Bithynia par O. viverrini s.l. dans le réseau de canaux (RC) dans la région métropolitaine de Bangkok (RMB) n’a jamais été évaluée. Cette étude visait à étudier la présence de B. siamensis siamensis et la prévalence de l’infection par O. viverrini s.l. chez ce mollusque dans le RC de la RMB, avec aussi une étude morphologique et des analyses moléculaires sur les cercaires d’ O. viverrini s.l. Les mollusques ont été prélevés au hasard dans le RC dans toutes les zones de la RMB de janvier 2018 à juillet 2019. Les spécimens de mollusques ont été identifiés et l’infection par les Digènes a été étudiée par excrétion et dissection. Les cercaires ont été identifiées à l’aide de méthodes morphologiques et moléculaires, y compris la PCR avec une amorce spécifique à l’espèce et une analyse phylogénétique bayésienne des séquences ITS2. Bithynia siamensis siamensis a été trouvé dans presque toutes les localités d’échantillonnage, avec des quantités et des fréquences de détection différentes. Sur un total de 7473 spécimens de B. s. siamensis, des infections par O. viverrini s.l. ont été détectées dans les régions du nord de Bangkok, Muang Nakhon Pathom, Krathum Baen et Lam Luk Ka avec une prévalence globale de 0,05 % (4/7473) et une prévalence respective de 0,22 % (1/455), 0,21 % (1/469), 0,40 % (1/253) et 0,16 % (1/614) dans les localités avec des mollusques positifs. Cette étude est la première enquête sur l’infection des Digènes dans l’habitat de type réseau de canaux en Thaïlande et a révélé une très faible prévalence d’O. viverrini s.l.

An increase in e-shopping and (last mile) parcel deliveries has contributed to a rapid growth of urban freight transportation. This generates major impacts on city sustainability and liveability. Current solutions for urban logistics concern road traffic, but multiple Dutch cities have an extensive range of city canals that could be used for freight transportation over water. It was investigated how the city canal network of Amsterdam can be utilised for last mile parcel delivery, and what the related effects are. A MILP formulation of a Two-Echelon, Multi-Depot, Capacitated Vehicle Routing Problem (2E-MD-CVRP) was developed. The model describes a network in which ships transport parcels to pre-determined satellite locations in the city centre, where the parcels are transferred to cargo e-bikes for the last mile of the delivery to the customer. The model was optimised by minimising the total costs, using the Genetic Algorithm (GA). The algorithm was able to find solutions but could not always stay within the constrained search space. Different possible network scenarios were evaluated, describing the consequences with respect to emissions, costs, and traffic flows. The results show promising economic, social, and environmental outcomes for a network with ships and cargo e-bikes instead of delivery vans. A daily and investment cost reduction of 16% and 36% respectively and a 𝐶𝑂2 emission reduction of 78.26% can be realised.

Nitrate pollution remains an unsolved issue worldwide, causing serious effects on water quality and eutrophication of freshwater and brackish water environments. Its economic costs are still underestimated. To reduce nitrogen excess, constructed wetlands are usually recognized as a solution but, in recent years, interest has been raised in the role of ditches and canals in nitrogen removal. In this study, we investigated the environmental and economical sustainability of nitrogen removal capacity, using as a model study a lowland agricultural sub-basin of the Po River (Northern Italy), where the role of aquatic vegetation and related microbial processes on the mitigation of nitrate pollution has been extensively studied. Based on the Life Cycle Assessment (LCA) approach and costs and benefits analysis (CBA), the effectiveness of two different scenarios of vegetation management, which differ for the timing of mowing, have been compared concerning the nitrogen removal via denitrification and other terms of environmental sustainability. The results highlighted that postponing the mowing to the end of the vegetative season would contribute to buffering up to 90% of the nitrogen load conveyed by the canal network during the irrigation period and would reduce by an order of magnitude the costs of eutrophication potential.

The Venice canal network requires periodic intervention to remove sediments that progressively accumulate. The most recent dredging operation was carried out in the second half of the 1990s and early 2000s. These sediments had accumulated over a period of more than 30 years and were highly contaminated with Cd, Cu, Hg, Pb, Zn and PAHs. Sediments deposited after the dredging work were investigated in 2005, 2009, 2014 and 2017 by analysing sediment cores collected from three sites in the canal network. Arsenic, heavy metal and PAH concentrations were observed to be much lower than past values, although Cu, Hg and PAH levels were still relatively high. The high Cu concentrations (mean 161 mg kg&minus, 1) are partly due to the widespread use of Cu-based antifouling paint. Current Italian regulations forbid the disposal of dredged sediments with these concentrations inside the lagoon, thereby increasing the cost of canal network maintenance.

Urban waterways have great potential in cargo transport to relieve the congestion in the overloaded road networks. This paper explores the potential of applying cooperative multi-vessel systems (CMVSs) to improve the safety and efficiency of transport in urban waterway networks. A framework consisting of vessel train formation (VTF) and cooperative waterway intersection scheduling (CWIS) is proposed. Two types of controllers are introduced. Intersection controllers solve the CWIS problems and assign each vessel a desired time of arrival and vessel controllers are responsible for the VTF in waterway segments and the timely arrival at the intersections. An alternating direction method of multipliers (ADMM)-based negotiation framework is proposed for the cooperation among the controllers. The simulation experiments involving the scenarios in which up to 50 vessels sailing in the canal network in Amsterdam are carried out to illustrate the effectiveness of the proposed approach. In the simulation of an isolated intersection, rescheduling is triggered when some vessels cannot arrive on time. Although some ASVs arrive later, the time that is needed for all the ASVs to pass through is the same after rescheduling. Moreover, we compare the cooperative situation with the proposed CMVSs with a baseline situation. In the baseline situation, vessels avoid collisions using the generalized velocity obstacle (GVO) method and cross the intersection with a first in, first out rule. The CMVSs show better path following performance, while the GVO method needs fewer velocity changes. From the perspective of efficiency, the CMVSs help to reduce the total time to pass through the intersection.

Caisteal Ormacleit [Ormiclate Castle], on the west side of South Uist, was constructed in the early 18th century by Clanranald for his wife Penelope, reputedly in the style of a French chateau, incorporating building materials imported from or via the east coast of South Uist at a time when there were neither roads nor carts. This high-status building (arguably more a fine house than a castle) and its origins and construction are reviewed in the context of historical sources, geology and topography. The history of the building and that of the couple for whom it was built had close associations with the Jacobite battles of 1689 (Killiecrankie) and 1715 (Sheriffmuir). The possible canal sections are reviewed in detail and a convincing case is provided for the existence of a canal network between the east coast of the Uists and the western situation of Caisteal Ormacleit, linking the Olaidh lochs, thus confirming the local tradition that the inland lochs of the Uists were used for boat-based transport and supporting the case for the existence of a wider navigable network within the Uist interior. Past intervention in water management has to be investigated in order to plan for future climate change impacts, and the Olaidh network is reviewed in this context.

In this study, based on the measurements of intracortical vascular canal structure, we investigated the disuse effect on local O2 supply in the cortical bones of growing rats. Hindlimb disuse was produced by unilateral sciatic neurectomy (SN) at 4 weeks age. The canal network structures within tibial cortical bone were evaluated in 8- and 12-week-old rats undergoing SN or no treatment (control) by synchrotron radiation micro-CT. Additionally, we developed an intracortical network model by combining the imaged-based canal network with a bone matrix containing theoretical lacunar–canalicular network, and determined the distribution of O2 concentration in bone tissue numerically. In the control bone, canal network was reduced with growth, resulting in decreased blood flow and averaged O2 concentration and increased spatial heterogeneity in tissue O2 concentration. Disuse reduced the canal network, leading to a lower flow rate, lower average O2 concentration and higher heterogeneity of O2 concentrations. However, the rarefaction of the canal network with growth was smaller under the disuse condition, and accordingly, the flow rate, the average O2 concentration and the heterogeneity of O2 concentrations remained stable. In particular, although the fraction of the canal volume was smaller, the densities of canal segments and bifurcation points under disuse condition tended to be higher than those of the control bone. The heterogeneity of O2 concentration was lower. Our results indicated that the disuse may lead to more uniformity in the canal network structure and thereby uniform O2, possibly contributing to O2 supply efficiency.

Remote Sensing is a very reliable and expeditious technique for assessment and mapping of surface waterlogged areas. In this study band ratio based NDWI index (Normalized Difference Water Index) was used for extracting water pixels from optical imageries. To overcome the limitation of false positives and cloud penetration associated with optical imageries waterlogged areas was also extracted using SAR (Synthetic Aperture Radar) images. Thresholding of NDWI for optical image and Sigma0 for SAR images was done using their respective histograms to distinguish water and terrestrial features. The total surface waterlogged areas in the district was calculated by integrating the results from both optical and SAR images. It was found that surface waterlogged areas varies temporally from pre-monsoon to post-monsoon period in Rohtak district, Haryana. The surface waterlogged area for pre monsoon period is around 9.7 km2 and for post monsoon period is 17.86 km2. The canal and surface drain network in the district was digitized using the high resolution Sentinel 2 MSS images. Since most of the canals in the area are unlined a buffer of 500 m either side of the canals and surface drains was considered to assess the impact of seepage and leakage from canals and surface drains. It was found that more than 50% of the total surface waterlogged areas fall within this buffer, clearly indicating the contribution of leakages from canals and surface drains on surface waterlogging.

Cortical bone porosity and specifically the orientation of vascular canals is an area of growing interest in biomedical research and comparative/paleontological anatomy. The potential to explain microstructural adaptation is of great interest. However, the determinants of the development of canal orientation remain unclear. Previous studies of birds have shown higher proportions of circumferential canals (called laminarity) in flight bones than in hindlimb bones, and interpreted this as a sign that circumferential canals are a feature for resistance to the torsional loading created by flight. We defined the laminarity index as the percentage of circumferential canal length out of the total canal length. In this study we examined the vascular canal network in the humerus and femur of a sample of 31 bird and 24 bat species using synchrotron micro‐computed tomography (micro‐CT) to look for a connection between canal orientation and functional loading. The use of micro‐CT provides a full three‐dimensional (3D) map of the vascular canal network and provides measurements of the 3D orientation of each canal in the whole cross‐section of the bone cortex. We measured several cross‐sectional geometric parameters and strength indices including principal and polar area moments of inertia, principal and polar section moduli, circularity, buckling ratio, and a weighted cortical thickness index. We found that bat cortices are relatively thicker and poorly vascularized, whereas those of birds are thinner and more highly vascularized, and that according to our cross‐sectional geometric parameters, bird bones have a greater resistance to torsional stress than the bats; in particular, the humerus in birds is more adapted to resist torsional stresses than the femur. Our results show that birds have a significantly (P = 0.031) higher laminarity index than bats, with birds having a mean laminarity index of 0.183 in the humerus and 0.232 in the femur, and bats having a mean laminarity index of 0.118 in the humerus and 0.119 in the femur. Counter to our expectation, the birds had a significantly higher laminarity index in the femur than in the humerus (P = 0.035). To evaluate whether this discrepancy was a consequence of methodology we conducted a comparison between our 3D method and an analogue to two‐dimensional (2D) histological measurements. This comparison revealed that 2D methods significantly underestimate (P

Intracortical canals are a major contributor to cortical bone porosity and influence its mechanical response. Canal networks act as stress concentrators and the magnitude of which depends on the size and spatial distribution of canals. In the present study, we investigated site-dependent variation in intracortical canal network morphological indices and their effect on the mechanical response of bone. For this, mid-diaphysis of rat tibia bones were scanned using high-resolution micro-CT and morphological indices were measured for four main anatomical sites-anterior, posterior, medial and lateral. Further, a micro-finite element (μFE) model was developed to quantify the stress concentration regions in different cortices. The fracture risk was assessed using an effective strain approach. Results show that canal porosity, canal orientation and canal length are site-dependent whereas canal diameter and canal number density are independent of the site. The lateral cortex has significantly higher porosity compared to the posterior cortex (p 0.05). The orientation of canals is found significantly different between endosteal and periosteal regions for anterior and medial quadrants. Canals are inclined at higher angles with bone axis in the endosteal region as compare to the periosteal region. The μ-FE results show that the regions with higher effective strain are concentrated around the canals. Further, failed element volume per unit bone volume is found highest for medial cortex whereas lowest for posterior cortex. The higher failed volume is associated with more radial canals in the medial cortex as compare to other cortices. The linear regression analysis shows that the volume of overstrained elements strongly depends on canal orientation (R

Decreasing nitrate concentrations is one of the most relevant Water Framework Directive (WFD) goals, which today is still unreached in several European countries. Vegetated canals have been recognized as effective filters to mitigate nitrate pollution, although rarely included in restoration programs aimed at improving water quality in agricultural watersheds. The Po di Volano basin (713 km2, Northern Italy) is a deltaic territory crossed by an extensive network of agricultural canals (~1300 km). The effectiveness in buffering nitrate loads via denitrification was assessed for different levels of in-stream emergent vegetation maintenance by employing an upscale model based on extensive datasets of field measurements. The scenarios differed for the canal network length (5%, 20%, 40%, and 60%) where conservative management practices were adopted by postponing the mowing operations from the middle of summer, as nowadays, to the early autumn, i.e., the vegetative season end. The scenario simulations demonstrated that the capacity to mitigate diffuse nitrate pollution would increase up to four times, compared to the current condition (5% scenario), by postponing the vegetation mowing to the end of the vegetative season in 60% of the canal network length. By preserving the in-stream vegetation in 20% of the canal network, its denitrification capacity would equal the nitrate load reduction target required for achieving, from May to September, the good ecological status according to the WFD in waters delivered to the coastal areas. Changing the timing of vegetation mowing may create a large potential for permanent nitrate removal via denitrification in agricultural landscapes, thus protecting the coastal areas when the eutrophication risk is higher. Conservative management practices of in-stream vegetation might be promoted as an effective low-cost tool to be included in the WFD implementation strategies.