Development of a Low-Cost Open-Source Platform for Smart Irrigation Systems

Nowadays, smart irrigation is becoming an essential goal in agriculture, where water and energy are increasingly limited resources. Its importance will grow in the coming years in the agricultural sector where the optimal use of resources and environmental sustainability are becoming more important every day. However, implementing smart irrigation is not an easy task for most farmers since it is based on knowledge of the different processes and factors that determine the crop water requirements. Thanks to technological developments, it is possible to design new tools such as sensors or platforms that can be connected to soil-water-plant-atmosphere models to assist in the optimization and automation of irrigation. In this work, a low-cost, open-source IoT system for smart irrigation has been developed that can be easily integrated with other platforms and supports a large number of sensors. The platform uses the FIWARE framework together with customized components and can be deployed using edge computing and/or cloud computing systems. To improve decision-making, the platform integrates an irrigation model that calculates soil water balance and wet bulb dimensions to determine the best irrigation strategy for drip irrigation systems. In addition, an energy efficient open-source datalogger has been designed. The datalogger supports a wide range of communications and is compatible with analog sensors, SDI-12 and RS-485 protocols. The IoT system has been deployed on an olive farm and has been in operation for one irrigation season. Based on the results obtained, advantages of using these technologies over traditional methods are discussed

The Self-Seeding of Anthemis arvensis L. for Cover Crop in Olive Groves under Intense Rabbit Grazing

Cover crops can be an effective means to protect soil and reduce risks of erosion in olive groves. However, for this protection to be significant, the vegetation must attain a significant amount of ground cover, which is estimated to be at least 30% during the rainy season. In olive groves on degraded soils, which occupy large surface areas in the olive-growing areas of the Mediterranean region, the establishment of cover crops may be an arduous challenge, particularly in areas with a high density of rabbits. In this study, we have selected two olive orchards with scarce natural vegetation located in Andalusia (southern Spain), in which rabbit populations intensively forage the cover crops, to test whether the self-seeding of an unpalatable species corn chamomile (Anthemis arvensis L.; A. arvensis for short) could achieve sufficient coverage for soil protection, in the year following that in which the broadcast-seeding was carried out for the implementation of cover crops. The hand broadcast-seeding of A. arvensis was carried out on sixteen elementary plots in the lanes of the two olive orchards in the autumn of 2015, and seed germination in the subsequent self-seeding took place in the autumn of 2016. The plant height and A. arvensis ground cover in these plots were measured throughout the two growth cycles, and aerial biomass was measured at maturity. The results showed that there were no significant differences in the maximum plant height between the two growth cycles (mean ± SD of 21.2 ± 1.6 cm), while the ground cover was significantly greater in the case of self-seeding, especially during the winter (37.2 ± 8.1 and 9.3 ± 6.7% for self-seeding and broadcast-seeding, respectively), and aerial biomass at maturity had more than doubled (99.7 and 43.9 g m−2, respectively). These data suggest that this unpalatable species could establish an effective herbaceous cover by means of self-seeding in olive groves on degraded soils that are being overgrazed owing to the high pressure of rabbits. Despite the poor establishment in the broadcast-seeding year, our findings indicate that A. arvensis might be an alternative cover crop that could help the sustainability of these threatened olive groves. Its high seed production (2000 to 4000 seeds per plant), and an early emergence just after the first autumn rains, should result in an increased ground cover by A. arvensis during the rainy season in the subsequent years of self-seeding. This, therefore, could contribute to soil conservation, in addition to providing other benefits of increased biodiversity and improvement for agricultural landscapes

Clinical guide of the Spanish Society of Nephrology on the prevention and treatment of peritoneal infection in peritoneal dialysis

[Resumen] Las infecciones peritoneales siguen constituyendo una complicación muy relevante de la diálisis peritoneal, por su incidencia todavía elevada y por sus importantes consecuencias clínicas, en términos de mortalidad, fracaso de la técnica y costes para el sistema sanitario. Las prácticas de prevención y tratamiento de esta complicación muestran una notable heterogeneidad derivada, entre otros factores, de la complejidad del problema y de la escasez de evidencia clínica que permitan responder de manera clara a muchas de las dudas planteadas. El propósito de este documento es proporcionar una revisión completa y actualizada de los métodos de diagnóstico, prevención y tratamiento de estas infecciones. El documento se ha elaborado tomando como referencia de partida la guía más reciente de la Sociedad Internacional de Diálisis Peritoneal (2016). Mientras que para el capítulo diagnóstico se ha adoptado una estructura más narrativa, el análisis de las medidas de prevención y tratamiento ha seguido una metodología sistemática (Grading of Recommendations, Assessment, Development and Evaluation [GRADE]), que especifica el nivel de evidencia y la fuerza de las sugerencias y recomendaciones propuestas, y facilita actualizaciones futuras de la guía. La gran extensión y numerosas recomendaciones o sugerencias emanadas de la revisión ponen de manifiesto la complejidad y gran número de facetas a tener en cuenta para un adecuado abordaje de esta importante complicación de la diálisis peritoneal.[Abstract] Peritoneal infections still represent a most feared complication of chronic peritoneal dialysis, due to their high incidence and relevant clinical consequences, including direct mortality, technique failure and a significant burden for the health system. The practices for prevention and treatment of this complication show a remarkable heterogeneity emerging, among other factors, from the complexity of the problem and from a paucity of quality evidence which could permit to respond clearly to many of the raised questions. The purpose of this document is to provide a complete and updated review of the main methods of diagnosis, prevention and treatment of these infections. The document has been elaborated taking as a reference the most recent guidelines of the International Society of Peritoneal Dialysis (2016). The diagnostic considerations are presented in a narrative style while, for prevention and therapy, we have used a systematic methodology (Grading of Recommendations, Assessment, Development and Evaluation [GRADE]), which specifies the level of evidence and the strength of the proposed suggestions and recommendations and facilitates future updates of the document. The length of the document and the many suggestions and recommendations coming out of the review underline the large number and the complexity of the factors to be taken into consideration for an adequate approach to this complication of peritoneal dialysis

In-depth analysis of soil management and farmers’ perceptions of related risks in two olive grove areas in southern Spain

This manuscript presents a questionnaire-based study aimed to provide a detailed analysis on the different soil management carried out by olive farmers in two representative olive-growing areas in southern Spain (Cordoba and Estepa), their perceptions on cover crop use and the possible influence of the different types of farms and farmers’ typologies on these perceptions. Our results show a relatively large variability of soil management, with fourteen options, as a result of a combination of different alternatives for bare soil and cover crops with the use or not of pruning residues, but with a great similarity between both areas. The results indicate a high adoption of soil conservation measures in the two study areas, with 63% of farmers using cover crops and 80% a mulch of pruning residues, higher than that reported in previous studies in Southern Spain, and a trend of lower use of these techniques by less experienced and younger farmers. This high penetration of soil conservation measures resulted in a significant reduction of soil erosion risk, as indicated by the relatively low values for the cover and management factor (C) of RUSLE, also calculated and presented in this study, but also the possibility of focusing further efforts on farmers with less experience. Our results indicate the persistence of a minor, but relevant, percentage of farmers using bare soil management (37%) and no mulching (20%), with a moderate concern on the impact of soil erosion on soil degradation and provision of ecosystem services. This suggests the need to concentrate efforts also on this cluster of farmers to enhance the success of what seems to be a remarkable expansion of the use of soil conservation measures in recent decades in Southern Spain, but also in similar areas in the Mediterranean basin

Comparison of Soil Organic Carbon Stocks Evolution in Two Olive Orchards with Different Planting Systems in Southern Spain

This study presents an evaluation of soil organic carbon (SOC) and stock (SOCstock) for the whole rooting depth (60 cm), spaced 55 months in two adjacent olive orchards with similar conditions but different tree densities: (i) intensive, planted in 1996 at 310 tree ha−1; (ii) superintensive, planted in 2000 at 1850 tree ha−1. This was carried out to test the hypothesis that olive orchards at different plant densities will have different rates of accumulation of SOC in the whole soil rooting depth. SOC increased significantly in the superintensive orchard during the 55-month period, from 1.1 to 1.6% in the lane area, and from 1.2 to 1.7% in the tree area (average 0–60 cm), with a significant increase in SOCstock from 4.7 to 6.1 kg m−2. In the intensive orchard, there was not a significant increase in SOCstock in 0–60 cm, average of 4.06 and 4.16 kg m−2 in 2013 and 2018, respectively. Results indicate a potential for a significant increase in SOC and SOCstock in olive orchards at higher tree densities when combined with temporary cover crops and mulch of chopped pruning residues. The increase is associated with an increase in SOC, mainly at a 0–15 cm depth. Results also point to the need for improve our monitoring capabilities to detect moderate increases in SOC

Postharvest shelf-life discrimination of nectarines produced under different irrigation strategies using NIR-spectroscopy

Quick assessment of storage time in fruits is important for both growers and consumers due to the fresh fruit market is becoming increasingly demanding with regard to product quality. This study sought to evaluate the ability of near-infrared reflectance spectroscopy (NIRS) to classify intact nectarines in post-harvest storage, as a function of pre-harvest irrigation strategies applied and post-harvest cold storage duration. A total of 220 nectarine fruits (Prunus persica (L.) Batsch cv. 'Sweet Lady') were sampled after 7, 14, 21 and 28 days of refrigerated storage (0 °C, 95% RH) and at commercial harvest time. Two commercially-available spectrophotometers were evaluated for this purpose: a handheld MEMS spectrophotometer of 1600-2400 nm and a diode-array Vis/NIR spectrophotometer of 400-1700 nm. Models developed using partial least squares 2-discriminant analysis (PLS2-DA) correctly classified between 86 and 96% of samples by post-harvest storage time using the handheld instrument, and between 66 and 89% in the case of the diode-array spectrophotometer. Classification models based on pre-harvest irrigation treatment classified 57-84% of the samples correctly, due to the similarity in physical-chemical properties of fruits in both irrigation strategies. These results showed that NIRS could be used to monitor changes in nectarine quality parameters during pre- and post-harvest as an essential tool for decision-making both in-field and on-line. © 2011 Elsevier Ltd.This research was funded by the Andalusian Regional Government under the Research Excellence Program (Project No. 3713 ‘Safety and Traceability in the Food Chain using NIRS’), and the European Commission IRRIQUAL Project (FP6-FOOD-CT-2006-023120).Peer Reviewe

Responses of nectarine to regulated deficit irrigation at the field scale

Irrigated agriculture is the primary user of water worldwide. Any method that reduces the consumption of water in irrigated agriculture without a reduction in yield and fruit quality would be highly desirable. One of the approaches currently being implemented in fruit trees and vines is regulated deficit irrigation (RDI). It consists of the application of water below the full crop-water requirements during periods of crop growth that are less sensitive to water deficit, which is a viable strategy during periods of water shortage. The results of on-farm experiments indicated that RDI based on stem water potential can be used successfully on nectarine trees in the area of Córdoba (Southern Spain) in deep soils. This strategy reduced the amount of irrigation water without reducing yield or crop value. One of the main limitations to the application of RDI to commercial orchards is the need of plant water status indicators like water potential. But to measure the latter is time consuming and therefore the number of trees that can be monitored continuously is a limiting factor. New tools should be developed for the early detection of water stress and one such tool is the high spatial resolution thermal remote sensing imagery. © ISHS 2012.Peer Reviewe

Response to regulated deficit irrigation of a nectarine orchard in Southern Spain

XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on CLIMWATER 2010: Horticultural Use of Water in a Changing Climate.Irrigated agriculture is facing restrictions due to water scarcity. Regulated deficit irrigation (RDI) is a technique that has been shown to reduce irrigation water use in fruit orchards and vines. In RDI, water is applied below crop requirements during certain developmental stages that are less sensitive to water stress. The objective of this study was to test the RDI strategy in a nectarine commercial orchard (Prunus persica (L.) Batsch ‘Sweet Lady’) in Southern Spain. The experiment was conducted in 2007 and 2008 and RDI was compared to the farmer’s irrigation schedule. In RDI treatment, water was withheld from the start of the irrigation period (end of May) until the start of the rapid fruit growth period (stage III). The strategy was to recover, as fast as possible, the water status of trees in order to avoid any water stress during stage III. Neither yield nor any measured parameter was altered by the RDI relative to the farmer’s irrigation schedule. In 2008, yield was slightly increased compared to 2007. There was a good relationship between the stem water potential during stage III, fruit volume, and total soluble sugars. These results demonstrate that water deficit must be avoided during this very sensitive period if the goal is to achieve large fruit size.Peer Reviewe