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Timely harvesting of fresh apples faces challenges due to labour shortage, and the modern approach of robotic harvesting has the potential to address this issue. The prevailing process of apple harvest robotics could not meet the demands of practical applications, mainly due to the lack of a suitable manipulator, because the existing ones are associated with low picking rates, fruit damage, and high costs. A prototype apple harvesting manipulator was developed, which includes a vacuum three-revolute-degrees-of-freedom end-effector, a three-prismatic-degrees-of-freedom Cartesian system, an RGB-D camera, and system integration. The vision positioning system and controller were designed to realise precise positioning and detachment of the manipulator. The major contribution of the current study is the three-revolute-degrees-of-freedom vacuum suction end-effector, whose performance evaluation was conducted in a commercial apple orchard. Experimental results showed that a 33 ϕ mm diameter suction cup achieved superior performance over a 43 ϕ mm cup. The method of rotation followed by pull proved to be more effective than only pulling for apple detachment. The results indicated that the apple's equatorial region was the optimal area for suction. Furthermore, the vacuum pressure should be at least −65 kPa to guarantee successful detachment. Experimental results showed that 83.1% of harvested apples had stems intact. For the developed manipulator, a 33 ϕ mm diameter suction cup, a rotate-and-pull separation method, and −65 kPa were recommended for practical applications. With the integrated new manipulator, the developed apple harvest robot has been demonstrated to have the potential to realise robotic apple harvesting. • A 3R-DoF end-effector for apple-picking robot was developed. • Apple's equatorial region recommended for suction. • -65 kPa pressure with a 33 mm diameter cup is recommended for use. • Rotation followed by retraction is recommended apple detachment. [ABSTRACT FROM AUTHOR]

Adhesion and detachment technologies play a crucial role in various fields, including industrial robot handling, transfer printing, medical applications, and crawling robot locomotion. Traditional pneumatic suction cups rely on bulky and noisy vacuum sources and need for preloading while electrostatic adhesion‐detachment devices generally cannot provide enough adhesion force. To address these shortcomings, a liquid‐amplified electrostatically driven suction cup is proposed inspired by octopus's sucker, including a negative pressure chamber with a wrinkle‐like membrane and a sealing ring. The negative pressure chamber generates the active adhesion force enhanced by the wrinkle‐like membrane, increasing the adhesion strength tenfold compared to pure electrostatic adhesion. The suction cup proposed herein has a remarkable capacity to generate an adhesion force of 56.4 times its weight, without preloading. Additionally, it can adapt to different materials, not only the dry but also the oil‐contaminated ones. This presented liquid‐amplified electrostatically driven suction cup can offer enhanced adhesion performance for applications in challenging environments.

Contamination of the environment by glyphosate (GLP) and its metabolite aminomethylphosphonic acid (AMPA) is still of major concern worldwide due to specific interactions among these molecules and soil and water. Two monitoring sites were established in the Prosecco wine production area (Conegliano and Valdobbiadene) in northeastern Italy, which has been included in UNESCO’s World Heritage List since 2019. The study aims to increase the knowledge about GLP dynamics in this area where it has been intensively used by farmers and the potential risk for groundwater pollution is still debated. Each site was equipped with two soil-water monitoring stations consisting of multisensor soil probes and suction cups at three soil depths (10, 30, and 70 cm). Soil and water were sampled for 10 and 6 months, respectively, and analyzed for GLP and AMPA concentrations, for a total of 242 samples to describe their vertical movement and dissipation dynamics. Soil properties, in particular, the different forms of Fe and Al oxide contents, and Freundlich adsorption coefficients were quantified along the soil profile. First attempts showed that glyphosate dissipation time was 36 ± 8 days in Conegliano and Valdobbiadene soils and fully completed in both after 6 months. In contrast, AMPA dissipation dynamic —first described by an original equation—was longer than that of GLP and fully dissipated after almost 300 days. GLP showed a strong binding affinity with clay and Fe and Al chelated to soil organic matter, which likely acted as cation bridges and in turn led to low GLP mobility. GLP and AMPA were mostly detected after heavy rainfall events at 70 cm depth, likely bypassing the porous matrix of the intermediate layers.

It is a key challenge for soft grasping devices to stably grasp unstructured objects with multi-size and multi-shape. The conventional single-function grippers have some limitations in grasping the above kinds of objects. This work proposes a modular four-modal soft grasping device (MFSGD), which consists of soft fingers, suction cups, soft wrapper, and other structures. It can perform a variety of grasping modes such as bending grasping mode, wrapping grasping mode, end lifting-sucking mode, and side fixed-sucking mode. It may be one of the devices with the most grasping modes at present. Moreover, the device adopts a fully modular design with different structures connected by magnets. It is not only convenient to disassemble or assemble, so as to solve the mutual interference of different modal structures problem during grasping, but also simplifies the fabrication of the multi-modal grasping device. In addition, this work matches the suitable grasping modes for objects of different shapes and sizes, and obtains the relative characteristics of the MFSGD. The proposed device can improve the ability of the grasping robots, and is expected to play an important role in economic and industrial fields. [ABSTRACT FROM AUTHOR]

Deterioration of groundwater quality due to nitrate loss from intensive agricultural systems can only be mitigated if methods for in-situ monitoring of nitrate leaching under active farmers' fields are available. In this study, three methods were used in parallel to evaluate their spatial and temporal differences, namely ion-exchange resin-based Self-Integrating Accumulators (SIA), soil coring for extraction of mineral N (Nmin) from 0 to 90 cm in Mid-October (pre-winter) and Mid-February (post-winter), and Suction Cups (SCs) complemented by a HYDRUS 1D model. The monitoring, conducted from 2017 to 2020 in the Gäu Valley in the Swiss Central Plateau, covered four agricultural fields. The crop rotations included grass-clover leys, canola, silage maize and winter cereals. The monthly resolution of SC samples allowed identifying a seasonal pattern, with a nitrate concentration build-up during autumn and peaks in winter, caused by elevated water percolation to deeper soil layers in this period. Using simulated water percolation values, SC concentrations were converted into fluxes. SCs sampled 30% less N-losses on average compared to SIA, which collect also the wide macropore and preferential flows. The difference between Nmin content in autumn and spring was greater than nitrate leaching measured with either SIA or SCs. This observation indicates that autumn Nmin was depleted not only by leaching but also by plant and microbial N uptake and gaseous losses. The positive correlation between autumn Nmin content and leaching fluxes determined by either SCs or SIA suggests autumn Nmin as a useful relative but not absolute indicator for nitrate leaching. In conclusion, all three monitoring techniques are suited to indicate N leaching but represent different transport and cycling processes and vary in spatio-temporal resolution. The choice of monitoring method mainly depends (1) on the project's goals and financial budget and (2) on the soil conditions. Long-term data, and especially the combination of methods, increase process understanding and generate knowledge beyond a pure methodological comparison. [ABSTRACT FROM AUTHOR]

Abstract While suction cups prevail as common gripping tools for a wide range of real‐world parts and surfaces, they often fail to seal the contact interface when engaging with irregular shapes and textured surfaces. In this work, the authors propose a suction‐based soft robotic gripper where suction is created inside a self‐sealing, highly conformable and thin flat elastic membrane contacting a given part surface. Such soft gripper can self‐adapt the size of its effective suction area with respect to the applied load. The elastomeric membrane covering edge of the soft gripper can develop an air‐tight self‐sealing with parts even smaller than the gripper diameter. Such gripper shows 4 times higher adhesion than the one without the membrane on various textured surfaces. The two major advantages, underactuated self‐adaptability and enhanced suction performance, allow the membrane‐based suction mechanism to grip various three‐dimensional (3D) geometries and delicate parts, such as egg, lime, apple, and even hydrogels without noticeable damage, which can have not been gripped with the previous adhesive microstructures‐based and active suction‐based soft grippers. The structural and material simplicity of the proposed soft gripper design can have a broad use in diverse fields, such as digital manufacturing, robotic manipulation, transfer printing, and medical gripping.

While suction cups prevail as common gripping tools for a wide range of real‐world parts and surfaces, they often fail to seal the contact interface when engaging with irregular shapes and textured surfaces. In this work, the authors propose a suction‐based soft robotic gripper where suction is created inside a self‐sealing, highly conformable and thin flat elastic membrane contacting a given part surface. Such soft gripper can self‐adapt the size of its effective suction area with respect to the applied load. The elastomeric membrane covering edge of the soft gripper can develop an air‐tight self‐sealing with parts even smaller than the gripper diameter. Such gripper shows 4 times higher adhesion than the one without the membrane on various textured surfaces. The two major advantages, underactuated self‐adaptability and enhanced suction performance, allow the membrane‐based suction mechanism to grip various three‐dimensional (3D) geometries and delicate parts, such as egg, lime, apple, and even hydrogels without noticeable damage, which can have not been gripped with the previous adhesive microstructures‐based and active suction‐based soft grippers. The structural and material simplicity of the proposed soft gripper design can have a broad use in diverse fields, such as digital manufacturing, robotic manipulation, transfer printing, and medical gripping. [ABSTRACT FROM AUTHOR]

A rigid in-plane matrix of suction cups is widely used in robotic end-effectors to grasp objects with flat surfaces. However, this grasping strategy fails with objects having different geometry e.g., spherical and cylindrical. Articulated rigid grippers equipped with suction cups are an underinvestigated solution to extend the ability of vacuum grippers to grasp heavy objects with various shapes. This paper extends previous work by the authors in the development of a novel underactuated vacuum gripper named Polypus by analyzing the impact of dynamic effects and grasping location on the vacuum force required during a manipulation cycle. An articulated gripper with suction cups, such as Polypus, can grasp objects by adhering to two adjacent faces, resulting in a decrease of the required suction action. Moreover, in the case of irregular objects, many possible grasping locations exist. The model explained in this work contributes to the choice of the most convenient grasping location that ensures the minimum vacuum force required to manipulate the object. Results obtained from an extensive set of simulations are included to support the validity of the proposed analytical approach.

The aim of this trial was to study the spatio-temporal variability in solution nutrient concentration under intensive greenhouse tomato production, to determine the number of suction-cups needed to obtain a representative sample and the influence by the position in the greenhouses. Twenty sampling points were selected within the greenhouse with one suction-cup per sampling point. One soil solution were sampled per point at weekly intervals to analyze for pH, electrical conductivity, chloride, nitrate, phosphate, sulfate, sodium, potassium, calcium, and magnesium (EC, Cl−, NO3−, H2PO4−, SO42—, Na+, K+, Ca2+, and Mg2+) concentrations. The pH, Cl−, H2PO4−, and SO42− concentrations showed no spatio-temporal variation but EC, NO3−, and K+ showed temporal variation. The spatial variability in EC, K+, Na+, Mg2+, and Ca2+ can be influenced by microclimate and topography. The numbers of suction cups required for a representative sample ranged from 1 to 10 depending on nutrient. [ABSTRACT FROM AUTHOR]

Groundwater pollution with nitrate is a big challenge for drinking water abstraction in regions with intensive agricultural land-use, specifically with high livestock densities on sandy soils in humid climates. Karst aquifers with high water flow velocities are extremely vulnerable to this problem. To cope with this situation, a field trial with an installation of ceramic suction cups under a randomised block design with a typical north-German cropping sequence of silage maize–winter wheat–winter barley was established in a karst water protection zone. Over three years, reduced nitrogen (N) application rates and N type (mineral or combined organic + mineral fertilisation) were tested for their effects on crop yields and leachate water quality below the root zone. Results showed no significant reductions in crop yields with 10/20% reduced N rates for cereals/maize and only slight reductions in cereal protein content. Nitrate concentration from adapted N rates was significantly lower in treatments with an application of organic fertilisers (−7.74 mg NO3-N l−1) with greatest potential after cultivation of maize; in only mineral fertilised plots the effect was smaller (−3.80 mg NO3-N l−1). Cumulative leaching losses were positively correlated with post-harvest soil mineral nitrogen content but even in unfertilised control plots losses >50 kg N ha−1 were observed in some crop-years. Reduced N rates led to decreased leaching losses of 14% (6.3 kg N ha−1 a−1) with mineral and 29% (20.1 kg N ha−1 a−1) with organic + mineral fertilisation on average overall cops and years. The presented study revealed the general potential of adapted fertilisation strategies with moderately reduced N applications (−10/−20%) to increase leachate water quality without affecting significantly crop yields. However, regionally typical after-effects from yearlong high N surpluses in livestock intensive farming systems are a limiting factor.

While plant roots respond consistently to nutrient availability under experimental conditions, our understanding of the role of such response in the field is hindered by poor knowledge of size and duration of nutrient patches there. In particular, knowledge of patch duration is critically important for understanding types of root response. We determined spatial and temporal variations in phosphate-P, nitrate-N and ammonium-N concentrations, and pH in an unproductive mountain meadow for which extensive data on fine-scale root distribution exist. We sampled soil solution weekly over 2.5 growing seasons using suction cups to in a hierarchical spatial design with the smallest grain of 3.3 cm. Overall concentrations of all studied nutrients were fairly low with occasional and short-term, but large-in-magnitude peaks, with no pronounced spatial or temporal structure at any scale. Temporal variation was much stronger than spatial variation, with both interannual differences and within-season differences playing a role. Phosphate-P was consistently highest in spring, whereas ammonium-N increased during summers. The ammonium-N, the major nitrogen source at the site, was negatively correlated with phosphate-P. Our data suggest that repeated sampling of soil solution in fixed positions is necessary to cover the entire extent of nutrient variation in the field. It shows that there are no stable nutrient patches at the fine scale, and the duration and size of nutrient patches are smaller than usual growth responses of roots. This implies that under such conditions, the best rooting strategy is homogeneous space occupation linked with fast physiological response to varying nutrient concentrations. [ABSTRACT FROM AUTHOR]

Abstract: Adhesion capabilities of various skin architectures found in nature can generate remarkable physical interactions with their engaged surfaces. Among them, octopus suckers have unique hierarchical structures for reversible adhesion in dry and wet conditions. Here, highly adaptable, biocompatible, and repeatable adhesive patches with unfoldable, 3D microtips in micropillars inspired by the rim and infundibulum of octopus suction cup are presented. The bioinspired synthetic adhesives are fabricated by controlling the meniscus of a liquid precursor in a simple molding process without any hierarchical assemblies or additional surface treatments. Experimental and theoretical studies are investigated upon to increase the effective contact area between unfoldable microtips of devices, and enhance adhesion performances and adaptability on a Si wafer in both dry and underwater conditions (max. 11 N cm−2 in pull‐off strength) as well as on a moist pigskin (max. 14.6 mJ peeling energy). Moreover, the geometry‐controlled microsuckers exhibit high‐repeatability (over 100 cycles) in a pull‐off direction. The adhesive demonstrates stable attachments on a moist, hairy, and rough skin, without any observable chemical residues. [ABSTRACT FROM AUTHOR]

The effects of regional water management practices (WMPs) on the soil salinity of a representative rice field under Mediterranean conditions (Thessaloniki plain, Greece) were investigated. The temporal variation of soil salinity parameters in the soil solution and in the exchangeable phase was monitored at and below the root zone (15–20 and 35–40 cm) during the growing season. The comparative analysis (ANOVA for p = 0.05) of the measurements before and after the growing season showed that: (a) for the soil solution of the 15–20 cm layer, Ca2+, Mg2+, K+, HCO3− and EC were significantly reduced, Na+ remained constant and Cl− increased, while in the 35–40 cm layer no significant differences were detected to all parameters except for Cl− which was increased; (b) for the exchangeable cations Ca2+, Mg2+ and K+ no significant differences were found, while exchangeable Na+ and ESP were significantly increased in both soil layers during the short period of soil drying before harvest. The final values of Na+ and ESP were quite low to indicate soil degradation hazard. Overall the results showed adequate performance of WMPs to preserve a good soil salinity status but with the cost of high water consumption, exceeding 2000 mm.

The aims of the study were to analyse the concentration of nitrate and ammonium ions in soil solutions obtained using MacroRhizon miniaturized composite suction cups under field conditions and to determine potential nitrogen leaching from soil fertilized with three types of fertilizers (standard urea, slow-release urea, and ammonium nitrate) at the doses of 90 and 180 kg ha, applied once or divided into two rates. During a 3-year growing experiment with sugar sorghum, the concentration of nitrate and ammonium ions in soil solutions was the highest with standard urea fertilization and the lowest in variants fertilized with slow-release urea for most of the months of the growing season. Higher concentrations of both nitrogen forms were noted at the fertilizer dose of 180 kg ha. One-time fertilization, at both doses, resulted in higher nitrate concentrations in June and July, while dividing the dose into two rates resulted in higher nitrate concentrations between August and November. The highest potential for nitrate leaching during the growing season was in July. The tests confirmed that the miniaturized suction cups MacroRhizon are highly useful for routine monitoring the concentration of nitrate and ammonium ions in soil solutions under field conditions. [ABSTRACT FROM AUTHOR]

In the last decades, due to remarkable technological improvements in ceramics production cycles and materials, the manufacturing and the commercialization of large-sized ceramic slabs have risen. While some phases of the process are well defined, there are some routines that lack systematic procedures and rely uniquely on the internal know-how of the single companies. In particular, this paper focuses on the handling and transportation of large-sized ceramic slabs, which are, in the vast majority of cases, performed by suction cups-based gripping devices. The scope of this paper is to investigate how the type of suction cup pattern and its geometrical parameters affect slab stresses and deformations and to provide a guideline for the choice of the pattern, in order to cope with some critical aspects associated with wide surface and small thickness of the slabs. In particular, some of the most common large slab sizes and thicknesses available on the market are considered, and the most suitable suction cup patterns (and their geometrical parameters) for handling them are evaluated in order to minimize slab stresses and deformations. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bioinspired soft suction cup for dynamic adsorption/desorption. • The realization of the wireless soft actuator by phase change and elastic polymer. • Controlled programmed climbing by remote light manipulation. • A light-driven soft climbing robot on tilted and slippery surfaces. Many organisms rely on a dynamic attachment mechanism to climb surfaces. Inspired by these organisms, researchers have developed soft climbing robots. Despite their rapid development in recent times, such robots have restricted application in complex environments, such as the lack of remote wireless actuation and attachment ability for climbing tilted or slippery surfaces. To address these issues, we report a light-driven dynamic adsorption/desorption soft suction cup inspired by rock-climbing fish (Beaufortia kweichowensis). Our suction cups utilize the volumetric change caused by changes in the gas–liquid phase in the inner chamber to generate suction and thrust. The repetitive changes in the gas–liquid phase, controlled by photothermal conversion, help achieve adsorption and desorption. We demonstrated that the suction cups based on negative pressure adsorption can easily help miniaturize soft robotic devices and adapt to multiple types of substrates, making our approach applicable to tilted or slippery surfaces. By integrating the soft suction cups for surface attachment by dynamic control and a shape memory alloy as a deformable body, we developed a soft climbing robot that can perform precise, facile, and programmed controlled climbing under different conditions via remote light manipulation. Four continuous and directional climbing sequences on tilted and slippery surfaces were demonstrated. The results are expected to help advance the application of light-driven soft robots on tilted or slippery surfaces [ABSTRACT FROM AUTHOR]

Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm −2 ), concentration of enhancing agent (0.25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm −2 did not increase removal and thus using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg −1 (removals: 78–86%) and 440–590 mg Cr kg −1 (removals: 35–51%), being within the 500 mg kg −1 limit for a clean soil only for Cu. While further optimization is still required for Cr, the removal percentages are the highest achieved so far, for a real Cu and Cr-contaminated, calcareous soil. The results highlight EDR potential to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution. [ABSTRACT FROM AUTHOR]

The two most common techniques used for fixation and of parts and materials in the industry are mechanical clutches and pneumatic suction cups. These have different characteristics, but generally perform the same function with respect to the displacement of material. The suction cups are noted for being great elasticity, being the best choice when the goal is to arrest or transport brittle materials, for example glass. The purpose of this work is to carry out some tests for lifting ideal parameters for the selection of the handling system loads by using a vacuum suction technology, automotive intended for industrial processes. In these assays will be evaluated first five physical aspects: the optional suction cup material, the air pressure system, roughness and weight of the materials to be handled and the level of vacuum generated by the system. In this work a data acquisition board will be implemented with the integration of the PIC microcontroller family, which will receive information via an analog signal from the pressure transducer, and make it available in an LCD display in order to pressure the system monitor. [ABSTRACT FROM AUTHOR]

Bio-logging tags are widely used to study the behavior and movements of marine mammals with the tacit assumption of little impact to the animal. However, tags on fast-swimming animals generate substantial hydrodynamic forces potentially affecting behavior and energetics adversely, or promoting early removal of the tag. In this work, hydrodynamic loading of three novel tag housing designs are compared over a range of swimming speeds using computational fluid dynamics ( CFD). Results from CFD simulation were verified using tag models in a water flume with close agreement. Drag forces were reduced by minimizing geometric disruptions to the flow around the housing, while lift forces were reduced by minimizing the frontal cross-sectional area of the housing and holding the tag close to the attachment surface. Hydrodynamic tag design resulted in an experimentally measured 60% drag force reduction in 5.6 m/s flow. For all housing designs, off-axis flow increased the magnitude of the force on the tag. Experimental work with a common dolphin ( Delphinus delphis) cadaver indicates that the suction cups used to attach the types of tags described here provide sufficient attachment force to resist failure to predicted forces at swimming speeds of up to 10 m/s. [ABSTRACT FROM AUTHOR]

This study focuses on the factors affecting nitrate removal via microbial denitrification in agricultural soils, and particularly on the quantity and quality of dissolved organic carbon. To assess the relationship among dissolved organic carbon, nitrate and low molecular weight organic acids (acetate and formate), grids of ceramic suction cups were established in the four most representative soil types of the lower Po River floodplain, cropped with maize. Results highlighted a direct relation between acetate and dissolved organic carbon in all sites. The best fit was obtained in soils were the main source of organic carbon was the maize residues. By comparing dissolved organic carbon and acetate versus nitrate concentration revealed that acetate can be used as a better proxy for denitrification in the field with respect to dissolved organic carbon. [ABSTRACT FROM AUTHOR]

Composition and concentration of soluble salts in the root-zone medium solution have an influence on plant growth, both by creating osmotic imbalance and via specific physiological toxicity of ions. Osmotic potential is related to electrical conductivity (EC) by mathematical models. The knowledge of the contribution of ions to the EC by means of theoretical estimations or regression models could link both effects of salts on nutrient uptake by plants and the development of new strategies for managing fertility and irrigation of horticultural crops. Solutions were obtained from nine commercial greenhouses (G), during the cultivation cycle of tomato plants var. Daniela. There were 273 samples, including irrigation water (IW), nutrient solutions (NS), and soil solutions (SS) obtained by suction cup. Solutions showed a wide range of EC and nutrient concentrations. Attending to nutrient concentration [nitrate (NO3−), potassium (K+), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), chloride (Cl−), and sulfate (SO42−)], the individual contribution of EC (Ω−1cm2mol−1) was estimated by means of the theoretical Debye–Hückel–Onsager equation reference, obtaining the ion molar conductivities (IMC) of 0.071 NO3−, 0.073 K+, 0.119 Ca2+, 0.106 Mg2+, 0.050 Na+, 0.076 Cl−, and 0.160 SO42−. On the other hand, the contribution coefficient for each parameter of EC (dS m−1) was estimated by means of multilinear regression, presenting the following coefficients: 0.033 NO3−, 0.072 K+, 0.124 Ca2+, 0.068 Mg2+, 0.038 Na+, 0.046 Cl−, and 0.026 SO42−. The determination coefficient of the model was 0.93. To validate both models 194 samples of solutions (IW, NS, and SS) obtained from different horticultural crops cultivated in greenhouses under fertigation in the Mediterranean area were used. The determination coefficients of the validated simple regressions were 0.83 and 0.89 for the theoretical and the multilinear models. [ABSTRACT FROM AUTHOR]

Urinations of ruminants on grazed pastures increase the risk of nitrate leaching. The study investigated the effect of reducing the length of the grazing season on nitrate leaching from a coarse sandy, irrigated soil during 2006-2007 and 2007-2008. In both years, precipitation was above the long-term mean. The experiment was initiated in a 4-yr-old grass-clover sward in south Denmark. Three treatments were as follows grazing only (G), spring cut followed by grazing (CG) and both spring and autumn cuts with summer grazing (CGC). Nitrate leaching was calculated by extracting water isolates from 80 cm depth using ceramic suction cups. Because of considerable variation in measured nitrate concentrations, the 32 installed suction cups per treatment were insufficient to reveal differences between treatments. However, weighted nitrate leaching estimations for G, CG and CGC showed estimated mean nitrate N concentrations of 23, 19 and 13 mg/L for an estimated proportion area occupied by urine patches of 0.33, 0.26 and 0.16, respectively. Thus, N concentrations in G and CG exceeded the EU limit of 11.3 mg N/L. Under the prevailing conditions, the time of urination did not appear important. The estimated background leaching calculated from suction cups presumably not situated under urine patches resulted in mean nitrate N concentrations of 2.6 mg/L. [ABSTRACT FROM AUTHOR]

Abstract: An extensive four-year research program has been carried out to explore and acquire knowledge about the fundamental agricultural practices and processes affecting the mobility and bioavailability of pesticides in soils under semi-arid Mediterranean conditions. Pesticide leaching was studied under field conditions at five different depths using suction cups. Monitoring of metolachlor, alachlor, atrazine, deethylatrazine (DEA), deisopropylatrazine (DIA), and bromide ions in soil water, as well as dye patterns made apparent the significant role of preferential flow to the mobility of the studied compounds. Irrespective to their adsorption capacities and degradation rates, atrazine, metolachlor and bromide ions were simultaneously detected to 160 cm depth. Following 40 mm irrigation, just after their application, both alachlor and atrazine were leached to 160 cm depth within 18 h, giving maximum concentrations of 211 and 199 μg L−1, respectively. Metolachlor was also detected in all depth when its application was followed by a rainfall event (50 mm) two weeks after its application. The greatest concentrations of atrazine, alachlor and metolachlor in soil water were 1795, 1166 and 845 μg L−1, respectively. The greatest concentrations of atrazine’s degradation products (both DEA and DIA) appeared later in the season compared to the parent compound. Metolachlor exhibited the greatest persistence with concentrations up to 10 μg L−1 appearing in soil water 18 months after its application. Brilliant blue application followed by 40 mm irrigation clearly depict multi-branching network of preferential flow paths allowing the fast flow of the dye down to 150 cm within 24 h. This network was created by soil cracks caused by shrinking of dry soils, earthworms and plant roots. Chromatographic flow of the stained soil solution was evident only in the upper 10–15 cm of soil. [Copyright &y& Elsevier]

The improvement of water and nutrient efficiency leads to a production model that is more sustainable with less water, fewer fertilizer inputs, and less environmental damages. High-technology fertigation equipment permits high precision in the nutrient solution application. Besides, the field measurement of soil water content by tensiometers and the extraction of soil solutions by suction cups allow a dynamic methodology management in agreement with real crop requirements. This trial was carried out to compare this dynamic fertigation management method (using tensiometers and suction cups) for tomato crops (Lycopersicum sculentum Mill. Forteza) under Mediterranean greenhouse conditions with other methods: the local traditional model, based only on technical consulting, and the classical model, by means of estimation of Kc and nutrient extractions references. The parameters studied were tomato yield, water, and fertilizer amounts applied during the cultivation as well as water- and fertilizer-use efficiency. The water used to prepare the nutrient solution was classified as C4-S3 following the Riverside classification system. Plants were grown from 15 August to 20 April. The results show that the supply of fertilizers during the cultivation has been significantly lower with classical and dynamic models. Dynamic method shows greater efficiencies for all the elements, except for potassium, and also decreases the water consumption, not affecting total yield. [ABSTRACT FROM PUBLISHER]

Abstract: Suction cups are used extensively throughout the packaging industry, as well as most other fields of robotics. In this present work, by means of a theoretical and experimental approach, the minimum value of the vacuum force and the adhesion coefficient able to guarantee the grasp and movement of the object with suction cups have been studied. Using a special test rig, experimental measurements regarding the slipping conditions obtained by stressing plates grasped by a flat suction cup with tangential forces and torque have been carried out. The experimental results have been compared with those obtained from a theoretical model in two suction cup–object contact pressure hypotheses (edge contact and full contact). [Copyright &y& Elsevier]

Biochar as a soil amendment is often described as a promising agricultural practice for climate change mitigation and adaptation. However, while recent research showed limited effects of biochar in temperate regions, its long-term impacts on nutrient management in-situ have been overlooked. Here we studied charcoal residues from pre-industrial kiln sites as a proxy to determine the effects of century-old biochar (~200 years old) on nutrient cycles of 3 land covers in a conventionally cropped field. We compared nutrient cycles of soil containing either century-old biochar (CoBC), recently pyrolyzed biochar (YBC) produced from similar feedstock (oak) and amended in similar amounts and a reference charcoal free soil (REF). For these three modalities, we characterized soil chemical properties, the pore water nutrient concentration evolution with time and depth using suction cups, and the crop nutrient uptakes. Our results revealed soil pore water nutrient concentrations strongly depended on biochar age. Indeed, YBC resulted in lower N-NO 3 - and K+ leaching but higher P-PO 4 – pore water concentrations in the topsoil Ap (0–30 cm) horizon. In CoBC higher K+ and Mg2+ concentrations occurred in the pore water than in REF for subsoil horizon E (30–60 cm) and Bt (60–100 cm). Beyond soil pore water, CoBC also strongly increased soil total N, available K+ and Ca2+ but decreased available P contents compared to REF and YBC. Finally, although no change in crop productivity occurred, lower N, K, Ca and higher Mg plant uptakes were observed for modalities with biochar. This resulted in no difference in terms of nutrient exports from the field in chicory but it significantly decreased N, K, Ca exports from biochar rich soil under winter wheat in straw. This study delivers the first field-based evidence that the effects of hardwood biochar on nutrient cycles change over its lifetime in a temperate Luvisol soil, whereby young biochar impacts mainly pore water nutrient concentrations and aged biochar mainly plant available contents. In such a strongly managed environment, no differences are noted in productivity despite strong changes in the nutrient cycle. Our study provides insights for addressing long-term effects of biochar in cultivated lands not only in terms of agronomic perspectives but through a biogeochemistry lens. • We analyzed pore-water nutrient dynamics in the soil profile of three land covers. • Young biochar decreases N-NO 3 - and K+ leaching in the studied temperate setting. • Total N, plant available K+, Ca2+ and Mg2+ were higher in soils with old biochar. • Winter wheat N, K and Ca exports were lower in soils with old biochar. [ABSTRACT FROM AUTHOR]

Understanding the composition and fluxes of vadose zone soil water is extremely important to many environmental studies, and hence the monitoring of soil solution is of basic interest for different scientific and practical fields, including pedologic studies, water-use management, fate and transport of environmentally consequential pollutants, monitoring of disposal from mining and industries, nutrient management of agricultural and forest ecosystems, ecology, and environmental protection. Soil solution sampling techniques for effectively monitoring the quality and quantity of vadose zone soil pore water have been used to assess the persistence and transport of potential groundwater pollutants, assess the ecological and human health impact of such pollutants, and develope appropriate remediation strategies. However, there is still no consensus as to best techniques for soil solution collection at most field or laboratory soil conditions. The purpose of this review is to evaluate different laboratory and in-situ techniques of vadose zone soil solution sampling. This comprehensive review presents and discusses advantages and disadvantages of these techniques, problems and limitations of some of these techniques, proper installation, operation and pretreatment of samplers, interaction of pollutants with sampler materials, and proper selection of samplers under a wide range of potential pollutants measurements to provide a background and guidelines for the evaluation of recent developments. [ABSTRACT FROM AUTHOR]

Abstract: Many engineering applications require joining two surfaces by temporary methods that do not harm either surface. The need for non-destructive surface bonding includes the need to resist axial moments. Suction cups in two different arrangements, in pairs at 180° apart and in fours at 90° apart, were pressed onto a polymerized thermoset polyester surface and then subjected to an axial moment. Defining failure as either sliding or complete loss of adhesion, the maximum torque applied before adhesive failure at the cup–plate interface was quantified using an MTS materials testing system. A linear relationship existed between the distance from the centroid of the cups and the applied torque at failure; also a linear relationship existed between the contact area of the cups and the tangential reaction force. Experiment verified that the applied load is distributed among the cups such that the tangential reaction force on each cup is proportional to its distance from the centroid; a coefficient of static friction between polyvinylchloride and polymerized thermoset polyester of 1.24 was calculated from the data. [Copyright &y& Elsevier]

Background, aim, and scope Contaminated mine drainage water has become a major hydrogeological and geochemical problem. Release of soluble metal contaminants and acidity from mining sites can pose serious chemical risks to surface and groundwater in the surrounding environment, and it is an important socio-economic factor addressed by working groups like SUITMA Morel and Heinrich (J Soils Sediments 8:206-207, 2008). The release of Zn and Pb from sulfide-bearing flotation residues of a small scale mine in Western Germany is investigated with focus on metal transfer to soil solution. Total contents of the soil material as well as soil water sampled with suction cups were analyzed. The influence of pH on leaching behavior was investigated with pH[substat] tests. Isotopic analyses helped assessing seepage water velocity. The aim of this study was the assessment of the environmental behavior of zinc and lead caused by the weathering of sulfide-bearing mine tailings. Especially, we address in this paper the dissolution of sphalerite (ZnS) in contrast to the well-known dissolution processes of pyrite (FeS2). Materials and methods Total metal contents of the soil samples were analyzcd by energy-dispersive X-ray fluorescence spectroscopy, total C concentration was measured using a CI-[NS elemental analyzer. X-ray diffraction (XRD) spectra were recorded from powdered soil samples. Soil water was sampled in nylon suction cups. Electrical conductivity (BC), pEt, and temperature of the soil water samples were measured in the field immediately after sampling. Major anions (F, Cl, NO[sub2], NO[sub3], SO[sub4]) were analyzed by ion chromatography, major cations (Ca, Na, K, Li) were analyzed by flame photometry, heavy metals (Zn, Pb, Fe, Mn, and Mg) by flame atomic absorption spectrometry. Tritiunt was analyzed by liquid scintillation counting (LSC), 180 and 2H were analyzed by isotope ratio mass spectrometry (1 RMS). pH[substat] tests were performed at four different pH values between 2 and 5. Results Total Zn contents of the soil samples averaged 10 g kg[sup-1], Pb contents averaged 2.5 g kg[sup-1], Fe 22 g kg[sup-1], S 8.0 g kg[sup-1], and total carbon 4.0 g kg[sup-1]. Below 2-m depth, soil samples had neutral pH values. Toward the surface, pH decreased down to pH 5.4 in P1 and P3, and to pH 5.9 in core P2, respectively. Dissolved contents of major ions (Mg, Ca, K, SO[sub4], and HCO[sub3]) in the soil solution increased with depth. Metal concentrations (Fe, Mn, Zn) decreased with depth. The solution pH was neutral to slightly alkaline in samples below 2 m and slightly acidic (pH-6) at 1 m depth. Tritium values are around 7 TU and correspond to modern rain, i.e., after 1975. stable isotope values plot on the global meteoric water line. The pH[substat] tests provide two kinds of information, the acid neutralization capacity after 24 h (ANC24) and the release of metals depending on pH. The ANC24 increases linearly with decreasing pH from about 60 mmol(eq) kg[sup-1] at pH 5 to about 460 mmol(eq) kg[sup-1] at pH 2. Zn and Fe release show a strong increase with decreasing pH to 126 and 142 mmol(eq) kg[sup-1], respectively. Pb release increases at pH <4 and Mn release at pH <5, both to about 10 mmol(eq) kg[sup-1]. Discussion With an average of 10 g kg[sup-1], this field site is highly enriched in Zn. In the oxidized topsoil, Zn concentrations are significantly lower than in the anoxic subsoil. The distribution pattern of total Zn contents and soil pH values indicate that the topsoil, which is prone to oxidation and acidification, is already depleted in Zn.… [ABSTRACT FROM AUTHOR]

In many peat land areas in The Netherlands target concentrations for nitrogen (N) and phosphorus (P) in surface water are exceeded. A considerable, but poorly quantified, fraction, of the N and P loading of surface water in these areas originate from the subsoil. Waterboards, responsible for the water management, are currently exploring options to improve surface water quality, whilst sustaining agricultural production. Therefore, insight into dynamics of nutrient pools in peat soils is required. The aim of this study was to measure concentration profiles (0–12 m) of the soil solution in an intensively managed grassland on peat soil and to explore the effects of a rise in surface water level on N and P loading of surface water, using budgeting approaches and two dimensional simulation modeling. The concentration profiles of N, P and Cl reflect by the presence of nutrient-rich anaerobic peat and a nearly impermeable marine clay in the subsoil. Concentrations of N, P and Cl tended to increase with depth till about 6 m and then decreased. In the top soil, inputs of N and P via fertilizers and animal manure were only partly retrieved in the soil solution, suggestion that biogeochemical processes, uptake and lateral transport processes had a dominant influence on dissolved N and P. Exploring scenario simulations showed that major drainage fluxes passed through the peat layer that transported nutrients to adjacent surface water. Raising surface water levels with 20 cm suppresses this kind of nutrient loading of surface water by more than 30%, but nutrient rich peat layers will remain persistent as a potential source of nutrients in surface water in many peat polders in the western part of The Netherlands. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess rapid‐analysis equipment for nitrate nitrogen, evaluating the measurement precision, the ease of use, and the robustness of the equipment. Three kinds of samples were collected: soil solutions taken by suction cup, hydroponic drainage solutions, and nutritive solutions obtained from the emitter. The equipment used to analyze the solutions for nitrate were Handion Priva electrodes, Nanocolor photometric equipment, and test equipment for ELE hydroponic solutions. The results were as follows: all equipment was easy to use, with clear and simple instructions for use in the field for fertigation management. The electrode appeared to be the most appropriate method to determine nitrate. The Nanocolor and ELE equipment underestimated nitrate concentrations for values greater than 3 mmol L-1; to ameliorate this problem, adjustment equations can be used. [ABSTRACT FROM AUTHOR]

Goal, Scope and Background. The suitability of leaching tests for the assessment of soil water concentrations is a controversial issue. The aim of this paper is to review and critically discuss the applicability and comparability of leaching tests in the scope of groundwater risk assessment of inorganic contamination and to discuss soil water sampling methods as alternative. Main Features. First, the theoretical background of leaching tests and the main leaching controlling parameters (pH, redox, ionic strength, reaction kinetics, surface, and speciation) are discussed. Experience with common batch leaching tests (the German DEV S4 test (S4), saturation soil extraction (SSE), ammonia nitrate extraction (ANE), and prismatic tests) are compiled and an emphasis is set on the comparability of the results of batch leaching tests. Additionally, the comparability between batch tests and column tests is discussed and comparison studies are reviewed. As a feasible alternative, soil water sampling strategies (the suction cup method and centrifugation) are outlined. Results and Conclusions. For an expedient application of leaching tests, it is crucial to identify the main release controlling parameters, which can be both site and contaminant specific. Possible controlling parameters are, for example, pH, redox conditions, specific surface area of the investigated material, liquid to solid-ratio, ionic strength, cation exchange capacity, DOC, speciation, temperature and contact time. It depends on the release process of the contaminant in the investigated material, which parameters are influencing the release predominantly. The following questions have to be answered: Is the release process availability controlled or solubility controlled and are there kinetic limitations? Suction cups are particularly useful for long-term monitoring. In contrast, centrifugation is a fast and simple method to sample soil water also at larger and heterogeneous sites. SSE or similar batch tests for coarse material are suitable if the soil water cannot be investigated directly. Contaminant concentrations of the SSE fit best to contaminant concentrations in soil water compared to other leaching tests. Concentrations measured with $4 tests are usually significantly lower than in real soil water due to the unrealistically high liquid to solid-ratio. The ANE is used for the evaluation of plant uptake. It does not represent realistic soil water concentrations. Cationic contaminants are usually significantly higher concentrated in ANE eluates, pHstatic tests provide an evaluation of the pH dependency of contaminant release and buffer capacity of the investigated material. It provides indications to release processes and often explains deviations in the results of different leaching tests. Previous practical experience and fundamental research studies show that a conversion of leaching test results, as is proposed by the (already withdrawn) DIN V 19735, is impossible. Correlations of results from different methods, regarding different kinds of materials and different sites, are not significant. This is due to different leaching processes. Recommendations. For short-term risk assessment, soil water should be sampled and investigated directly by suction cups (for monitoring purposes) or centrifugation (for inventory purposes). If this is not possible, the SSE or analogous batch tests for coarse material with a narrow L/S ratio should be applied. A suggestion could be a modified saturation soil extraction where a soil column is saturated and the eluate is removed by suction at the bottom of the column. With this method, an unsaturated column test could follow in the same vessel. In order to assess the long-term leaching behavior, total contents of the investigated material have to be taken into account additionally.… [ABSTRACT FROM AUTHOR]

A variety of sources can specifically create uncertainty and/or bias in scientific process and stage of acquisition measurement data when in situ data acquisition is considered. From the sequence of data acquisition in an experimental site and a bibliographic review of possible biases, a set of experiments is proposed to quantify the global bias in the measurement of pesticide concentration. The analysis begins with the data which wants to be initially measured by instrumentation use and ends with the data finally presented. The data acquisition is then chronologically analysed in steps, describing the data states between which bias may exist. The study specifically focuses on the data with regard to the pesticide concentration in soil solution. Large biases, have been found, depending on the compound's passage through ceramic cups or during storage. These losses can be respectively attributed to the adsorption and screening processes, and the adsorption and transformation reaction, the intensity of which varies according to the sensitivity of compounds for these processes. Advice and solutions to minimize the bias that occurred in the studies are then provided (change in device or strategy, pesticide rejection, data correction). The general study and acceptance of the notion of bias are finally advocated. [ABSTRACT FROM AUTHOR]

A rigid in-plane matrix of suction cups is widely used in robotic end-effectors to grasp objects with flat surfaces. However, this grasping strategy fails with objects having different geometry e.g., spherical and cylindrical. Articulated rigid grippers equipped with suction cups are an underinvestigated solution to extend the ability of vacuum grippers to grasp heavy objects with various shapes. This paper extends previous work by the authors in the development of a novel underactuated vacuum gripper named Polypus by analyzing the impact of dynamic effects and grasping location on the vacuum force required during a manipulation cycle. An articulated gripper with suction cups, such as Polypus, can grasp objects by adhering to two adjacent faces, resulting in a decrease of the required suction action. Moreover, in the case of irregular objects, many possible grasping locations exist. The model explained in this work contributes to the choice of the most convenient grasping location that ensures the minimum vacuum force required to manipulate the object. Results obtained from an extensive set of simulations are included to support the validity of the proposed analytical approach. [ABSTRACT FROM AUTHOR]

Underactuated grippers represent an appealing solution that allows complex objects to be grasped and manipulated via passive adaptation of the hand with objects via simple control inputs. The grasping ability can be further improved in combination with vacuum gripping, i.e., by outfitting the gripper phalanges with suction cups, that remains a largely underinvestigated solution. This paper presents a novel gripper, referred to as POLYPUS, that features underactuation and vacuum grasping to handle uneven and even objects made of different materials, including cardboard, glass, sheet metal, and plastic. Being characterized by a solid frame, POLYPUS does not fall in the soft gripper category, while preserving similar adaptability. It provides unique load lifting capacity that ranges from light to heavy objects, whereas most of the existing grippers are tailored for a specific target payload. Being modular in design, POLYPUS can be easily reconfigured for a wide range of object sizes and applications. Results obtained from an extensive set of simulations are included to evaluate the grasping performance expressed in terms of the minimum suction force to handle objects of varying shape, material, and pose. • A novel gripper that features underactuated and vacuum grasping. • Uneven and even objects made of different materials can be handled. • Light and heavy objects manipulated in contrast to standard grippers. • Results from an extensive set of simulations to evaluate the grasping performance. [ABSTRACT FROM AUTHOR]

Groundwater pollution with nitrate is a big challenge for drinking water abstraction in regions with intensive agricultural land-use, specifically with high livestock densities on sandy soils in humid climates. Karst aquifers with high water flow velocities are extremely vulnerable to this problem. To cope with this situation, a field trial with an installation of ceramic suction cups under a randomised block design with a typical north-German cropping sequence of silage maize–winter wheat–winter barley was established in a karst water protection zone. Over three years, reduced nitrogen (N) application rates and N type (mineral or combined organic + mineral fertilisation) were tested for their effects on crop yields and leachate water quality below the root zone. Results showed no significant reductions in crop yields with 10/20% reduced N rates for cereals/maize and only slight reductions in cereal protein content. Nitrate concentration from adapted N rates was significantly lower in treatments with an application of organic fertilisers (−7.74 mg NO3-N l−1) with greatest potential after cultivation of maize; in only mineral fertilised plots the effect was smaller (−3.80 mg NO3-N l−1). Cumulative leaching losses were positively correlated with post-harvest soil mineral nitrogen content but even in unfertilised control plots losses >50 kg N ha−1 were observed in some crop-years. Reduced N rates led to decreased leaching losses of 14% (6.3 kg N ha−1 a−1) with mineral and 29% (20.1 kg N ha−1 a−1) with organic + mineral fertilisation on average overall cops and years. The presented study revealed the general potential of adapted fertilisation strategies with moderately reduced N applications (−10/−20%) to increase leachate water quality without affecting significantly crop yields. However, regionally typical after-effects from yearlong high N surpluses in livestock intensive farming systems are a limiting factor. [ABSTRACT FROM AUTHOR]