Green wall irrigation procedures are a particularly important and hard task, given that the quality of the green wall depends on them. There is currently a wide variety of irrigation programmers ...available, with a range of functions and prices, thereby replacing manual activities and making it easier to maintain green walls. This paper proposes the use of low-cost automated irrigation programmers via a freeware called Arduino. The system is based on air and substrate measurements to ensure optimal plant growth and high water-use efficiency. At certain thresholds, the irrigation system is activated. This not only makes irrigation more convenient but also helps to reduce energy consumption, increases irrigation efficiency and saves time. The data is then sent via Transmission Control Protocol using Internet of Things technology, in this case ThingSpeak. The platform compiles the data and presents them in simple graphical format, thus enabling real-time monitoring from wherever there is Internet access. Together with Arduino, the project incorporates the Raspberry pi system that operates like a database via Hypertext Transfer Protocol Wi-Fi received by a Structured Query Language (MySQL) server using Hypertext Preprocessor. These data are used for the subsequent analysis of green wall performance.
As we wrote in the summary of this special issue, the purpose of this Special Issue is to report, in more detail, research of water resources management in the frame of sustainable development ...
ABSTRACT
The effects of the North Atlantic Oscillation (NAO) on a second order‐mixed exponential stochastic model (MC2ME) of daily precipitation were detected for 33 weather stations located in ...southern Spain. The stations exhibit a wide range of elevations and distance from the Atlantic Ocean and consequently have large variations of mean annual precipitation and mean annual number of wet days. Annually, periodic parameters were obtained by numerical maximum likelihood fitting of Fourier series utilizing 54 years of concurrent data for each station. NAO effects were determined by perturbing these parameters by functions of the NAO Index. The Akaike information criterion (AIC) was used to select the appropriate number of Fourier harmonics for each parameter and to determine if the non‐stationary model with perturbed parameters was superior to the annually periodic model. Likelihood ratio tests showed that improvements in log likelihood functions by NAO perturbations of the logits of transition probabilities and the periodic function of the mean of the mixed exponential were highly significant. Improvements in the log likelihood functions were obtained by perturbing only during the winter months. Limited goodness of fit analyses by simulations showed that the NAO perturbations led to increased variance of annual precipitation and greater ranges of annual maximum and minimum precipitation as compared to simulations with annually periodic parameters.
El arroz es regado por inundación manteniendo una altura de agua constante y alcanzando unos requerimientos de agua elevados. A la salida de la parcela hay un canal de desagüe cuyo control permitirá ...establecer prácticas para reducir el gran consumo de agua. Se ha diseñado un aforador de estrechamiento largo para cubrir el intervalo completo de caudales a aforar. Puesto que el canal de desagüe tiene una sección trapecial, la garganta del aforador será también trapecial para disminuir las pérdidas de carga. Un nuevo procedimiento se ha desarrollado en una hoja de cálculo Excel que permite diseñar directamente las dimensiones de la sección estrechada, talud de las paredes y anchura de la base, eligiendo previamente el límite modular, la altura del umbral y la longitud del estrechamiento más en concordancia con las características del canal. Los resultados demuestran la precisión y viabilidad del procedimiento.
The development of the wet bulb under drip irrigation in sand-covered soils presents a different behavior compared to the one observed in homogeneous soils. Moreover, the presence of a very active ...crop imposes a series of variations that have not been fully characterized. The aim of this work is to present the data acquisition methodology to calibrate and validate the Hydrus-3D model in order to safely define the evolution of moisture in wet bulbs generated in stratified “sanded” soils characteristic of greenhouses with intensive pepper crop under drip irrigation. The procedure for collecting and processing moisture data in stratified soils has been defined. Soil permeability; retention curve, texture, and bulk density have been measured experimentally for each material. It has been found that the inclusion of a previous day in the simulation improves model predictions of soil moisture distribution. In soils with less gravel, a lower average stress and a more homogeneous moisture distribution were observed. It has been proved that the Hydrus-3D model can reproduce the behavior of sand covered soils under intensive greenhouse growing conditions, and it has been possible to verify that the predictions are adequate to what has been observed in the field. In view of the results, the Hydrus-3D model could be used to establish future irrigation strategies or to locate the optimal placement point of tensiometers that control irrigation in sandy soils for intensive agriculture.
La escasez de agua y la creciente demanda de alimentos imponen la utilización de tecnologías más eficientes en el regadío. Por tal motivo, se abordaron los fundamentos hídricos e hidráulicos del ...riego subsuperficial a demanda mediante vasos comunicantes (RSVC), estudio de caso cultivo de col rizada. El sistema estuvo compuesto por un depósito de agua, una cubeta con carga hidráulica constante, una línea de derivación, laterales de riego, emisores y vasos de cultivo. La pérdida de carga en el sistema, para el lateral más alejado, fue 7.38491 mm.c.a., permitiendo operar a presiones muy bajas sin requerimiento energético. Debido a la continuidad hidráulica, generada por la tasa evapotranspirativa, los cultivos no sufrieron estrés hídrico, obteniéndose un rendimiento promedio de 360 g de materia fresca/planta, con una eficiencia de uso del agua de 22.38 g/l, rendimientos favorables cuando se compara con otros estudios.
En este trabajo, se han evaluado hidráulicamente una selección de goteros de bajo caudal escogidos entre los más usados en el riego de cultivos hortícolas en invernaderos bajo plástico en la ...provincia de Almería. Este tipo de goteros son los ofrecidos actualmente por los fabricantes. Esta caracterización hidráulica proporcionará su caudal y su uniformidad de emisión que son los parámetros fundamentales para el estudio de la eficiencia en el uso del agua en riego por goteo. En total, han sido 21 los goteros analizados, distinguiendo según su tipo de inserción (interlínea, pinchados e integrados), según su comportamiento hidráulico (compensantes y no compensantes) y, dentro de los compensantes, antidrenantes y no antidrenantes. Todos ellos con un caudal nominal entre 1 y 2,4 L·h-1. Los ensayos han sido realizados siguiendo los criterios de la norma ISO 9261-2004 para el cálculo del coeficiente de variación debido a la fabricación y la ecuación de gasto del emisor en un banco de ensayos. Los resultados muestran un buen comportamiento de la mayoría de los emisores y un bajo valor del coeficiente de variación de caudal debido a la fabricación. En el caso de los emisores compensantes, el exponente hidráulico de la ecuación de gasto es próximo a cero. No se han encontrado diferencias significativas entre los coeficientes de variación de caudal debido a la fabricación entre emisores compensantes y no compensantes, ni tampoco se han encontrado diferencias significativas entre los compensantes según fueran antidrenantes o no antidrenantes, en relación con este coeficiente. En el caso de los emisores antidrenantes, las presiones de cierre no se cumplen en ningún caso y las presiones de apertura solo en el 50% de los casos.
The interception of rainfall by vegetation greatly affects the hydrology of a basin. The main objective of this paper is to evaluate the effect of annual rainfall variability on the interception in ...isolated individuals of two of the most common types of vegetation, Pinus pinea and Cistus ladanifer, in a Mediterranean watershed. For this, experimental data were taken for four years and the Rutter interception model was used to calculate the canopy drying time, while Rutter and Klaassen methodologies were used to determine the storage capacity of the canopy. On the whole, 29.6% of rainfall was intercepted for pine, and 17.7% for rockrose. Stemflow accounted for 0.3% for pine and 17% for rockrose, while 70.1% of the rainfall fell as throughfall for pine and 65.3% for rockrose. However, in dry years, the interception percentage almost doubled that of wet years. An average canopy drying time of 9.2 hours was established for pine, and 4.4 hours for rockrose. Approximately equal results of canopy storage capacity were obtained from both methods (1.8 mm for pine and 0.7 mm for rockrose). Both species registered higher values of canopy storage capacity in dry years than in wet years.
•Irrigation by kanis have been evaluated for first time.•The performance of pre-Hispanic irrigation systems, kanis and zigzag corrugated irrigation systems, has been compared.•Kanis irrigation system ...is more advisable for the irrigation of small surface areas.•The major issue with the zigzag corrugated furrow irrigation is precisely the high loss of water through runoff.
In the area that is today Bolivia, the pre-Hispanic era was a period of great learning, marked by the management and use of natural resources, where farming became one of the cornerstones of production and where irrigation was an essential practice. In different areas, pre-Hispanic surface irrigation methods are still in use today, such as kanis irrigation and zigzag corrugated furrow irrigation. The primary aim of this paper is to compare the performance of the above irrigation systems using a potato crop at the Choquenaira Experimental Farm located at an altitude of 3877 m above sea level. During the growing cycle, there were seven irrigation events for each system.
With kanis irrigation, the advance times were very short due to the high flow rates and the shortness of the furrows. As a result, there were no major variations in the opportunity time. The volume of water applied per hectare during the growing cycle was 1315m3, while the crop-water requirement was estimated at 1854m3/ha. The application efficiency of irrigation varied from 18% to 100%, with deficit irrigation in three events.
In the case of zigzag corrugated furrow irrigation, the advance times were higher due to the greater length of the furrow. The total volume of water applied was 2595 m3/ha while the calculated crop-water requirement was 2644m3/ha, thus quite similar. The application efficiency of irrigation varied from 18% to 91.3%, with deficit irrigation and high values of surface runoff.
The time required for irrigation, and by extension the labour required, is greater for the kanis irrigation system, which is consequently regarded as more suited to small areas of land. The yield of potato tubers was larger using the kanis method compared to the zigzag furrow irrigation method due to the more efficient use of water.
•An experimental study increasing the area of cultivation of the hydraulic structures called suka kollus is presented.•Suka kollus are one of the most important hydraulic structures based on ...ancestral technology developed in the Andean region.•Management options have been considered which allow farmers to keep the benefits associated with this production system.•The best results were achieved in mixed drainage systems with one or two intermediate drains.
The suka kollus, considered among the most important hydraulic structures of ancestral Andean technology, are used as a technique for crop production in flood-prone soils, enabling subsurface irrigation of crops by means of drainage channels. They also generate a thermoregulatory effect depending on the channel/ridge ratio and the total size of the infrastructure. They could be a valuable way of making use of marginal soils if some of the drainage channels are replaced by underground drains to increase the area of cultivation. This work was therefore undertaken to study the flow of water under a “mixed” drainage system (surface and subsurface drainage) adapted to the suka kollus system.
The work was carried out in marginals in the Kallutaca area, La Paz, Bolivia. The potato cultivar ‘Imilla negra’ (Solanum tuberosum ssp. andigena) was used in four treatments with different platform widths: T1 (control), the traditional system in which all drainage was via open channels; and T2, T3 and T4, where one, two and three channels were, respectively, replaced by drains. The study describes the comparison between T1 treatment, with open drains at a depth of 1 m and platform width of 6.5 m (T1) with the other treatments, i.e. subsurface pipe drains at a depth of 1.2 m and a platform widths of respectively 12 m (T2, where one channel was replaced by a drain), 18 m (T3, where two channels were replaced by drains) and 25 m (T4, where three channels were replaced by drains)
The results showed that the distance of 6.5 m between drainage channels, commonly used in traditional suka kollus, was less than the calculated distances. As such, it was possible to expand the area of the platforms by setting the drainage channels between 10 and 14 m apart. Crops yield in the T2 and T3 treatments (10.67–11.35 Mg/ha, respectively) are significantly higher compared to the traditional open drainage system, T1 (8.33 Mg/ha) and the wider platform width of 25 m, T4 (7.3 Mg/ha) due to the higher height of plants and the greater number of tubers per plant, compared to the control. Likewise, the high clay percentage of the second stratum of the T3 treatment could be beneficial in terms of greater retention of water at the root level, mainly for periods of water deficit. The crop water requirements were covered by the upward flows from the water table and by precipitation, demonstrating that the suka kollus system is sustainable under current climatic conditions.
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