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The inter-row soils in conventionally run citrus orchards in Eastern Spain lose fertility, either physically, chemically, or biologically, as a consequence of machinery traffic and the use of herbicides. In order to regain inter-row soil fertility, two grass-cover management alternatives to the commonly used herbicide-kept bare management, namely, spontaneous plants and fescue, were established and left for four years until their effects on several physical, chemical, and biological parameters were monitored for two years more. The fescue ground cover exhibited lower average and maximum soil temperatures due to higher evapotranspiration rates but also higher annual soil water content on average and, additionally, higher rhizodeposition. Despite the fact that these new beneficial conditions helped enhance the soil's biological fertility under fescue, the physical or chemical fertilities did not improve and neither did the organic carbon (SOC). The spontaneous plants also enhanced the biological fertility, but in this case, beneficial conditions were reflected by improvements in the chemical fertility, particularly the exchangeable potassium, and in the physical fertility by increasing the surface hydraulic conductivity and decreasing the bulk density. In the inter-rows of this citrus orchard, a seeded grass cover does not seem able to provide any soil fertility enhancement in comparison to a spontaneous one; rather the opposite. However, a lack of natural or man-driven nitrogen inputs poses a constraint to SOC gains. For this aim, the annual surface application of organic nitrogen-rich materials or even better, the fostering of N-fixing organisms would be recommended. [ABSTRACT FROM AUTHOR]

Observed variations in the ground electrical conductivity (σb*) measurements obtained with EMI instruments depend on several soil proxies that influence crop growth and development such as salinity (σe), contents of water (θw), clay (wc) and organic matter (wom) and bulk density (ρb). However, the relative contributions of all these to σb* are unknown. This knowledge is needed to improve the planning and interpretation of σb* data for precision agriculture applications. Recently, a semi-empirical model has been developed to relate σb* measurements taken with an EM38 device to σe, θw, wc, wom and ρb and also soil temperature (t). In this work this model was subjected to a global sensitivity analysis (GSA) based on the soil data obtained during two surveys carried out, one in summer and the other in autumn, in an ample irrigated area in SE Spain. On the basis of the multiple linear regression meta-models developed for the σb* measurements, these were found to linearly respond to the soil properties (R2 between 0.92 and 0.96) and thus, the GSA could be based on their standardised regression coefficients. According to these, the soil characteristics explain the following percentages of variance in σb* (PV): 30–34 (σe), 8–20 (θw), 32–47 (wc), 0.6–2.6 (wom), 5.7–7.5 (ρb) and 0.3–0.4 (t) with changes from the summer to the autumn season of − 4, − 12 and + 15 in the PV explained by the most influential properties, respectively, σe, θw and wc. The results of the GSA will help the planning and interpretation of σb* measurements for improving crop management. [ABSTRACT FROM AUTHOR]

Aim: Power lines can represent an important source of bird mortality through collision. The identification of more susceptible species, in terms of expected population‐level impacts, requires detailed biological and mortality information that is often difficult to obtain. Here, we propose a species prioritization method based on relatively easily accessed information, aimed to identify both species and areas with the potentially highest extinction risk due to collision with power lines. Location: As a case study, we applied this method to the communities of resident breeding birds of Spain and Portugal. Methods: For each considered species, the method takes into account the morpho‐behavioural susceptibility to collision with power lines, the susceptibility to extinction and the spatial exposure to collision with power lines. Results: Our method highlighted that the most susceptible species were large, long‐lived and slow‐reproducing birds, often habitat specialists with hazardous behavioural traits (especially flight height and flocking flight), with high spatial exposure to collision risk with power lines and unfavourable conservation status. Based on the distribution ranges of these species, we produced a map of hotspots for extinction risk due to collision of such priority species for each country. These areas should be considered a priority for the implementation of mitigation measures including route planning and wire marking. Main conclusions: Overall, the proposed method can be applied to any bird community in any geographic area of the world where information on power‐line distribution and published information on species traits, distribution and conservation status is available, generating valuable lists of both priority species and areas in which collision risk with power lines can potentially produce local or even global extinctions. [ABSTRACT FROM AUTHOR]

Abstract: Many empirical equations have been developed to predict the properties of saturation extracts, primarily electrical conductivity, from the properties of soil water extracts of 1 to 5 ratio. Soil water 1:5 extracts are more rapidly and reproducibly prepared than saturation extracts. However, the electrical conductivity of saturation extracts (EC se) is the benchmark to assess soil salinity. Analysis of the information provided by the electrical conductivity of soil 1:5 extracts (EC 1:5) is a prerequisite to guide equation development and to use EC 1:5 for soil salinity assessment. A total of 135 soil samples were taken from 39 sites at up to four different depths per site, down to a maximum depth of 95cm in an irrigated agricultural area in SE Spain. Soil 1:5 extracts obtained from each sample were analysed for twelve chemical properties: concentration of sodium, ammonium, potassium, magnesium, calcium, chloride, nitrite, nitrate, sulphate, alkalinity and electrical conductivity. A principal component analysis (PCA) was applied to the correlation matrix of the log-transformed data set. The equilibrium status of 1:5 extracts with regard to gypsum was assessed with the chemical speciation programme SALSOLCHEMIS. The soil gypsum content was determined by using an adaptation of the classical method of total dissolution of soil gypsum, adequate to determine low gypsum contents, i.e. lower than 2%. Three principal components, accounting for 82% of the variance in the correlation matrix, were retained after eigenvector extraction. The first component accounted for 53% of the variance and was interpreted as representing the extract salinity due to gypsum dissolution. The second component accounted for 16% of the variance and was interpreted as representing the component of the extract salinity due to salts more soluble than gypsum, such as sodium and chloride salts. The information about soil salinity is split in two components in the 1:5 extracts, which are not easily resolved, whereas only one salinity component was obtained in the saturation extracts. The EC 1:5 is a reliable property to estimate EC se, with a 95% confidence interval of ±1.2dSm−1, only when it is lower than 1dSm−1. When EC 1:5 is higher than 2.4dSm−1 it could also be reliably used to estimate soil salinity only if the 1:5 extract is gypsum-saturated, which is highly probable when the soil gypsum content is higher than 1.5%, or when the saturation extract is not gypsum-saturated, situation which happens when soil gypsum content is lower than 0.2%. When the EC 1:5 is between 1 and 2.4dSm−1, it provides poor information about the EC se, which could be between 4 and 14dSm−1 unless the soil gypsum content is negligible, i.e. lower than 0.2%. The usefulness of the EC 1:5 to estimate soil salinity can be extended when it is used in conjunction with an estimate of soil gypsum content. The development of more than one equation to estimate EC se from EC 1:5 depending on soil gypsum content is recommended. [Copyright &y& Elsevier]

Abstract: Calcite equilibrium characterisation of soil solutions is needed in order to provide soil salinity modellers with reliable solubility constants in solutions where the hypothesis of equilibrium can be accepted. A total of 134 soil samples were taken from 39 sites at 2, 3, or 4 depths per site, down to a maximum depth of 95 cm, during a survey in the irrigated agricultural area of the Segura River Lowland (SE Spain). Soil saturation extracts obtained from each sample were analysed for thirteen chemical properties: Na, NH4, K, Mg, Ca, Cl, NO2, NO3, SO4, alkalinity, chemical oxygen demand, and electrical conductivity. A principal component analysis (PCA) was then done on the correlation matrix from the log-transformed data set. Three principal components, accounting for 76% of the variance in the correlation matrix, were retained after eigenvector extraction. These components were interpreted as representing salinisation, soil superficiality as opposed to soil depth, and fertilisation status. Sodium, chloride, magnesium, calcium and sulphate concentrations were highly correlated with the first principal component and were interpreted as explaining the variance in electrical conductivity of the soil saturation extracts, and by proxy soil salinity. Alkalinity, pH, chemical oxygen demand, and nitrite were correlated with the second principal component. Nitrate, potassium and ammonium concentrations were correlated with the third principal component, and their variation in soil was independent of soil saturation extract salt content and soil depth. According to the interpretation of the second principal component, soil saturation extracts are further than the solutions in the saturated pastes from being in equilibrium with calcite. The calcite oversaturation status of soil saturation extracts is related to soil organic matter content. [Copyright &y& Elsevier]

• In this second version, some improvements have been done. We summarize the main ones:. • Abstract & introduction now our goal is to offer a "complete explanation of how a winning strategy of creation and development of a DBE can: i) ensure survival of incumbents in the face of threats from digital disruptive actors, and ii) transform consumer habits very quickly, due to the superior created value as a new solution for that need. We used the novel reformulation of the modularity theory (Baldwin, 2020c) which can be considered as a first step for a DBE-specific theorisation and supportive framework to understand the deep social impact of the different network effects generated." We reformulate the research question as follows: how was bizum's DBE implemented by traditional banking entities and what are the success factors which lead the new mobile instant payment ecosystem in Spain?. • Literature review Now the section is split into two subsections: 2.1. Fintech and open payments & 2.2. Digital business ecosystems under modularity Theory. We have increased the number of references: +23 new ones, 11 out of them are dated from 2018 on. We think that we offer a wider perspective of DBE phenomenon split in four themes: business issues, technical issues, DBE conceptualization and DBE artefacts. Bizum is a great case of study, not only because it represents a proven success DBE that it was created and implemented by Fintech incumbents in Spain, but because, in only five years and with only seven workers, Bizum has penetrated into more than 70% of the Spanish banking population. It offers a digital solution for instant payments by using an app.. • Research method We have included a summary table (Table 1) where the main research topics are collected. Additionally, more references and further details support to explain better our research process. We have developed a new interview with Fernando Rodríguez, business development Manager. With that new interview we cover more than 40% of Bizum´s employees and the key actors are part of our selection. • Bizum case analysis We start with a clarification of this DBE's nature as an open transactional platform following the suggested theoretical framework: the modularity theory (Baldwin, 2020). We illustrate that nature with a new figure (Fig. 2). The content is split into two subsections: 4.1. Deployment & 4.2. Value proposition and social impact. Later, we cover the two main topics of our research: the internal DBE creation and the massive customer adoption. In order to make easier to check the rich inputs that we obtained during the interviews, we summarize the main verbatim in two tables, one for each topic (Tables 3 & 4). • Limitations and future research directions Tittle of this section has changed to describe its content, as suggested by reviewers. • Conclusions The main conclusions are as follows: The first contribution is the empirical evidence of a successful implementation of a DBE, allowed a number of traditional banking entities to compete in a rapidly changing market through a disruptive solution. Secondly, the network effect developed on Bizum's DBE justifies the great acceptance that it has as a means of mobile payment between end users (P2P). The third contribution is that, along with the network effect, Bizum's value proposition favors a deep and quick transformation of payment habits among Spanish users belonging to different generations. Finally, we highlight the critical factors of Bizum's DBE which explain how it was built and why it was able to succeed by providing digital value in a critical common need: payments. Technological disruption and social transformation are shaping and explain the radical changes introduced in financial services. A new technological mix of mobile-apps, big data, blockchain, AI, cloud computing and digital platforms is taking place with unprecedented speed and is forcing traditional banks to consider this technology to form part of new collaborative value creation networks, such as digital business ecosystems (DBEs). Traditional payment habits based on cash and credit or debit cards are being replaced by new innovative formats of mobile instant payment among end users (P2P). Through a single case study – Bizum's DBE – the purpose of this research is to explore how successful was the defensive strategy developed by traditional banking entities with the objective to lead the new mobile instant payment ecosystem in Spain. The findings show that Bizum's DBE is helping traditional banking entities to create a superior digital value that is being adopted very quickly by a huge number of users in Spain. The main contribution of this study is the complete explanation of how a winning strategy of creation and development of a DBE can: i) ensure survival of incumbents in the face of threats from digital disruptive actors, and ii) transform consumer habits very quickly, due to the superior created value as a new solution for that need. We used the novel reformulation of the Modularity Theory (Baldwin, 2020 c) which can be considered as a first step for a DBE-specific theorisation and supportive framework to understand the deep social impact of the different network effects generated. [ABSTRACT FROM AUTHOR]

• A portable Vis-NIR spectrometer was used to record persimmon foliar reflectance. • Leaf Cl− was next determined with a laboratory reference method. • A PLSR model for leaf Cl− assessment based on the foliar reflectance was developed. • The use of the day of the year improved modelling and was thus, included in the model. • The degradative effect of Cl− on chlorophyll might explain the model predictive ability. New methods for the non-destructive, rapid and reliable assessment of leaf chloride (Cl−) are needed in many agricultural salt-threatened areas throughout the World. Although portable visible near-infrared spectrometers could be useful for this task, accompanying models for leaf Cl− assessment on basis their visible near-infrared (Vis-NIR) spectra had yet to be developed. To study the feasibility of such models, a persimmon orchard was grown in E Spain and irrigated with eight waters ranging in Cl− concentration from 70 to 350 mg/L. Then, six times throughout the growing season the Vis-NIR foliar reflectance spectra of various representative leaves per Cl− treatment were recorded with a portable miniature Vis-NIR spectrometer. The leaf Cl− was subsequently determined in the same leaves with a laboratory reference method. Next, both the Cl− and spectral data were analyzed using descriptive statistics, mathematical data transformations, principal components analysis (PCA) and partial least squares regression (PLSR). A wide, sufficiently normal-distributed and representative range of leaf Cl− content from 0.17 to 3.14%Cl− was obtained. With correlation coefficients exceeding +0.65 between 390 and 472 nm and between 690 and 692 nm, the foliar reflectance was the spectral data correlated the most with the leaf Cl−. Remarkably, both wavelengths intervals are where chlorophyll a has its two absorbance maxima in the visible region. A PLSR model including all the wavelengths in the Vis-NIR reflectance spectra plus the day of the year, attained values of R2 = 0.78, RMSE = 0.34%Cl− and RPD = 2.18 in the external validation. However, for leaf Cl− below 1.5%Cl−, i.e., when Cl− assessment is most needed, this model presented R2 = 0.55, but RMSE = 0.08%Cl− and RPD = 5.5, in addition to a bias of +0.04%Cl− and a standard error of 0.05%Cl−. These results show that portable Vis-NIR spectrometers can be useful for the non-destructive, rapid and even reliable assessment of leaf Cl−. The potential of this methodology for other crop plants and inorganic ions should be tested. [ABSTRACT FROM AUTHOR]

SALTIRSOIL (SALTs in IRrigated SOILs) is a model for the medium to long term simulation of soil salinity in irrigated, well-drained lands. Once the algorithms were verified, the objective of our study was to validate SALTIRSOIL under one of several water quality and management scenarios in Mediterranean agriculture. Because drip and surface are the most common irrigation systems in irrigated agriculture in Valencia (Spain), the validation was performed with climate, soil, irrigation water (composition and management) and crop (species and management) information from an experimental plot surface irrigated with well water and planted with watermelon that has been monitored since the late spring of 2007. To carry out the validation, first we performed a global sensitivity analysis (GSA). Second, we compared simulated soil saturation extract composition against measured data. According to the GSA, SALTIRSOIL calculations of soil salinity seem to be most affected by climate (rainfall and evapotranspiration) with 60% of explained soil salinity variance, water salinity with 26% of explained variance, and then irrigation with 4%. According to the closeness of the first comparisons between predictions and measurements, SALTIRSOIL does not seem to be affected by any systematic error, and as a consequence, neither inclusion of new parameters nor calibration of the others already included would be needed at least for surface irrigation. The validation of SALTIRSOIL continues under other water quality and irrigation management scenarios. [Copyright &y& Elsevier]

• Mulching and no-tillage improved vine water status regardless of watering regime. • Alleviations of water stress resulted in decreases in grape phenolic composition. • Soil management and water regime caused interactive effects on water use efficiency. • Bulk density increased at the soil surface due to mulching and no-tillage. Optimizing water use in vineyards is crucial for ensuring the sustainability of viticulture in semi-arid regions, and this may be achieved by minimizing direct water evaporation from the soil through the use of mulching. In this context, the current study aimed at assessing the combined effects of the vine-row application of an organic mulch (vine prunings) and no-tillage under two water regimes on soil properties, plant water and nutritional status, yield and must composition of grapevine (Vitis vinifera L.) cv. Bobal grown under semi-arid conditions. For this purpose, a field experiment in a split-plot design was carried out for three years (2016–2018) in a mature Bobal vineyard located in Eastern Spain. Two soil management strategies (tillage and organic mulching with no-tillage) were assessed under two water regimes (rainfed and deficit drip irrigation) with four replications per combination. Vine responses were determined by measuring midday stem water potential, leaf nutrient concentrations, pruning weight, yield components and grape composition. Soil properties were assessed at the end of the experiment. Mulching and no-tillage positively affected vine water status under both water regimes, resulting in reductions in grape phenolic composition. Interactive effects of both water regime and soil management on water use efficiency were found. Regardless of soil management practice, irrigation increased yield and pruning weight when compared to rainfed conditions. Soil management had slight effects on vine nutritional status. At the end of the experiment, soil compaction increased and infiltration decreased as a consequence of mulching and no-tillage. Organic mulch and no-tillage improved vine water status, however, considering the final soil surface compaction and low water infiltration rate, longer-term studies are necessary to assess the sustainability of combining both practices. [ABSTRACT FROM AUTHOR]