Search results for " drip irrigation"
showing 10 items of 13 documents
Linking the Kinetic Energy Fraction and Equivalent Length Method for Trickle Irrigation Design under Local Losses
2020
New methods using analytical relationships to design drip irrigation laterals and subunits have been introduced in recent years based on the assumption that minor losses can be neglected. This assumption could be relaxed by applying the equivalent method, which makes it possible to account for minor losses, such as those caused by emitter connections, through formulas based on the rationale that an equivalent length of the drip lateral produces the same losses. However, equivalent length formulas are empirical; thus, they do not necessarily cover the entire range of conditions in the real-world contexts in which the formulas will be applied, and their extrapolation could lead to erroneous r…
Using HYDRUS-2D model to assess the optimal drip lateral depth for eggplant crop in a sandy loam soil of central Tunisia
2016
The main objective of the work is to assess the optimal drip lateral depth for Eggplant crop (Solanum melongena L.) irrigated with a drip system in a sandy loam soil by means of field measurements and simulation models. Initially, the performance of Hydrus-2D was assessed based on the comparison between simulated soil water contents (SWC) and the corresponding measured in two plots, in which laterals with co-extruded emitters were laid on the soil surface (drip irrigation, DI-0) and at 20 cm depth (subsurface drip irrigation, SDI-20), respectively. In order to identify the optimal position of the lateral, the results of different scenarios, obtained by changing the installation depth of the…
Optimizing subsurface dripline installation depth with Hydrus 2D/3D to improve irrigation water use efficiency in the central Tunisia
2015
The main objective of the work is to optimize drip installation depth for Eggplant crop irrigated with surface or subsurface drip irrigation systems to improve irrigation Water Use Effeciency (WUE), by means of field measurements and simulations carried out with Hydrus-2D model. Initially, a comparison between simulated Soil Water Contents (SWC) and the corresponding measured in two plots, in which laterals with coextruded emitters are laid on the soil surface (T0) and at 20 cm depth (T20), respectively. In order to choose the best position of the lateral, the results of different simulation run, carried out by choosing a deeper installation (T45) depth. Simulated SWC’s resulted fairly clos…
Subsurface Drip Irrigation and ICT for the Innovative Irrigation Water Management: Application to a Citrus Crop (C. reticulata cv. Tardivo di Ciacull…
2020
Subsurface drip irrigation (SDI) is considered one of the most efficient irrigation systems because it allows the optimization of crop water productivity maximizing, at the same time, farmers’ economic benefit. However, to take full advantage of SDI systems it is necessary to prevent emitter obstructions caused by root intrusion, as well as to apply water-saving strategies, such as regulated deficit irrigation (RDI). Regarding the first aspect, manufacturers are claiming different techniques to protect emitters from root intrusion, such as mechanical barriers, addition with different chemical compounds into the emitter itself or chemicals into irrigation water. On the other hand, the applic…
Using Hydrus 2-D Simulation model to evaluate wetted soil volume in subsurface drip irrigation systems.
2007
Drip irrigation is considered one of the most efficient irrigation systems. Alternatively to the traditional drip irrigation systems, laterals can be installed below the soil surface. Realizing the subsurface drip irrigation (SDI), which recently has been increasing in use as a consequence of advances in plastics technology, making SDI equipment more affordable and long lasting. Due to its potential high efficiency SDI may produce benefits, especially in places where water is a limited source. As the use of SDI is relatively new, a better understanding of the infiltration process around a buried point source can contribute to increased water use efficiency and consequently the success of dr…
Evaluation of subsurface drip irrigation emitters on a split-root container-grown citrus rootstock (citrange ‘Ccarrizo’)
2022
Among irrigation systems, subsurface drip irrigation allows obtaining values of water use efficiency higher than 90%. However, when emitters are installed below the soil surface, root intrusion can represent the main cause of emitter occlusion. To prevent this phenomenon, manufacturers normally include herbicides in the plastic matrix of the emitters. Objectives of this paper were: i) to evaluate the effectiveness of alternative anti-root agents embedded in the same emitter model and ii) to identify their possible effects on the growth of a commonly adopted citrus rootstock (citrange ‘Carrizo’). Five different anti-root agents were tested in 8 lined trees, planted in split-root containers i…
Vegetative and Reproductive Behaviour of Vitis vinifera L. (cv. ‘Cabernet Sauvignon’) Vines Growing Under Non-Irrigated Conditions and Moderate Water…
2007
An experiment was carried out to evaluate the effect of different levels of water stress and different irrigation systems to the vegetative and reproductive behaviour of Cabernet Sauvignon ines/140Ru, vertically trained, during the growing season 2003-2004. The vineyard was located in Sicily (in the south of Italy); the soil was loamy-sand and the climate semi-arid. Were compared five treatments: four treatments irrigated, maintaining a moderate water stress level, by drip irrigation (T1) and sub-irrigation (T2, T3 and T4) and one treatment non-irrigated (T5). The sub-irrigation treatments were different by the number and the distance of the water tubes by the rows of vines. The results sho…
Agro-hydrological models and field measurements to assess the water status of a citrus orchard irrigated with micro-sprinkler and subsurface drip sys…
2021
Compared to the micro-sprinkler irrigation, traditionally used in citrus orchards, subsurface drip systems (SDS) allow increasing the water use efficiency (WUE); when coupled with water-saving strategies, like regulated deficit irrigation (RDI), further increase of WUE are possible. Combining measurements of soil water content (SWC) and weather data with measurements of midday stem water potential (MSWP) makes it possible to identify irrigation scheduling parameters for the RDI. However, measurements of MSWP are destructive and time-consuming, and also require skilled operators. For all these reasons, the use of the agro-hydrological models, such as the FAO-56 model, can be considered a sur…
Discussion on "Modeling Approaches for Determining Appropriate Depth of Subsurface Drip Irrigation Tubing in Alfalfa"
2020
The discussed paper deals with the quite interesting topic of design and management of subsurface drip irrigation (SDI), with the aim to identify the appropriate depth at which to install driplines to avoid wetting the soil surface. The study proposes the results of simulations, obtained with the well-known HYDRUS 2D/3D model version 2.x, and considering three different irrigation management strategies applied on alfalfa crop cultivated in two different soil types in Holtville, California.
A new record of the desert truffle Picoa lefebvrei in Saudi Arabia
2012
A new record of Picoa lefebvrei from Saudi Arabia is reported accompanied by notes on its taxonomy, ecology, and distribution.