Search results for "Drip irrigation"
showing 10 items of 40 documents
Long-term non-sustainable soil erosion rates and soil compaction in drip-irrigated citrus plantation in Eastern Iberian Peninsula.
2021
Abstract Agriculture is known to commonly cause soil degradation. In the Mediterranean, soil erosion is widespread due to the millennia-old farming, and new drip-irrigated plantations on slopes, such as the citrus ones, accelerate the process of soil degradation. Until now, the published data about soil erosion in citrus orchards is based on short-term measurements. Long-term soil erosion measurements are needed to assess the sustainability of drip-irrigated citrus production and to design new strategies to control high soil erosion rates. The objective of this study is to assess long-term soil erosion rates in citrus plantations and report the changes in soil bulk density as indicators of …
Minor Losses and Best Manifold Position in the Optimal Design of Paired Sloped Drip Laterals
2018
Explicit relationships for optimal designing rectangular microirrigation units on uniform slopes: The IRRILAB software application
2018
Abstract Many attempts have been made to provide easy tools for designing microirrigation units. However, most of these have dealt with numerical solutions, which require many trial-and-error attempts and time-consuming iterations, performed by applying the basic hydraulic equations from the manifold to the end of both the downhill and the uphill sides of the laterals. Recently, analytical procedures to optimally design paired drip laterals on uniform slopes were proposed, providing readily obtainable results and energy saving. Although these analytical solutions can be practically applied, they only make it possible to design a one-lateral unit; to be really interesting for practical appli…
Analytical Approach Determining the Optimal Length of Paired Drip Laterals in Uniformly Sloped Fields
2015
Microirrigation plants, if properly designed, allow for water use efficiency to be optimized and high values of emission uniformity to be obtained in the field. Disposing paired laterals, for which two distribution pipes extend in opposite directions from a common manifold, can contribute to reducing the initial investment cost that represents a limiting factor for small-scale farmers of developing countries where in the last decade, the diffusion of such irrigation systems has been increasing. The objective of this paper is to propose an analytical approach to evaluate the maximum lengths of paired drip laterals for any uniform ground slope, respecting the criteria to maintain emitter flow…
Simplified Procedure to Evaluate Head Losses in Drip Irrigation Laterals
2005
The lateral lines of a drip irrigation system consist of pressurized pipelines with inline or online emitters. Proper hydraulic design of drip laterals usually requires the accurate evaluation of the total head losses, represented by friction losses along the pipe and the emitters, and local losses due to the emitter connections. This paper extends the local loss evaluation procedure, previously obtained for coextruded laterals, on the basis of new experiments. In addition, a simplified procedure was proposed based on the constant outlet discharge assumption for a quick evaluation of total head losses in drip irrigation lines, taking into account the total local loss due to the emitter conn…
Experimental Analysis of Local Pressure Losses for Microirrigation Laterals
2004
The accurate design of drip irrigation laterals needs to consider the variation of hydraulic head due to pipe elevation changes, head losses along the lines, and also, at a given operating pressure, emitter discharge variations related to manufacturing variability, clogging, and water temperature. Hydraulic head variations are consequent to both the friction losses and local losses due to the in-line or on-line emitters along the pipe, which determine the contraction and subsequent enlargement of the flow streamlines. Moreover, in-line emitters usually have a smaller diameter than the pipe, and therefore an additional friction loss must be considered. Evaluation of energy losses and consequ…
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.