0000000000174683
AUTHOR
Loris Franco
Agro-hydrological models and field measurements to assess the water status of a citrus orchard irrigated with micro-sprinkler and subsurface drip systems
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…
Effetti di differenti metodi irrigui e volumi di adacquamento sullo stato idrico e sullo sviluppo vegetativo estivo di piante di agrumi
Negli ultimi decenni, per massimizzare l’efficienza d’uso della risorsa idrica in agricoltura, si è cercato di migliorare le performance degli impianti di distribuzione oltre che implementare strategie di gestione che prevedano l’applicazione di condizioni di deficit idrico (DI) durante specifiche fasi del ciclo fenologico delle colture. Per l’applicazione di tali strategie è necessaria la conoscenza specifica del sistema suolo-pianta-atmosfera, in modo da evitare effetti negativi sullo sviluppo vegetativo e di conseguenza sulle produzioni. Obiettivo del lavoro è stato quello di valutare gli effetti di differenti modalità di distribuzione dell’acqua irrigua e volumi di adacquamento sullo st…
Detecting crop water requirement indicators in irrigated agroecosystems from soil water content profiles: An application for a citrus orchard.
Abstract Most perennial crops sensitive to water scarcity, such as citrus, can benefit from efficient water management, which allows for reduced water consumption while increasing crop production on a long-term basis. However, when implementing water-saving strategies, it is necessary to monitor soil and/or plant water status in order to determine crop water demand. A plethora of devices providing indirect measurements of volumetric soil water content, such as the “drill and drop” multi-sensors probes (Sentek, Inc., Stepney, Australia), have been developed over the last decade. The objective of the paper was to analyse time-series of soil water content profiles and meteorological data colle…
Verifica dell’applicabilità del metodo irriguo sub-superficiale su colture agrumicole e ottimizzazione dell’uso della risorsa idrica
Gli impianti di subirrigazione (SDI), in relazione alla posizione interrata dei gocciolatori permettono la riduzione dei consumi irrigui, garantendo la possibilità di utilizzo di risorse altrimenti non utilizzabili. Tuttavia, i costi di investimento iniziali risultano maggiori di quelli relativi ai tradizionali impianti di microirrigazione e pertanto, diventano economicamente vantaggiosi, se l'efficienza del sistema viene garantita per periodi di almeno 15-20 anni. La SDI, inoltre, permette di ottenere valori elevati di efficienza d’uso dell’acqua, spesso superiori al 90%, se associata ad un monitoraggio continuo dello stato idrico del suolo e della pianta e ad una corretta stima delle esig…
Evaluation of subsurface drip irrigation emitters on a split-root container-grown citrus rootstock (citrange ‘Ccarrizo’)
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…
Implementing a cyber-physical system to monitor soil water status and environmental variables for irrigation scheduling
The most advanced research on irrigation at farm scale, following the paradigm “more crop per drop”, has been aimed at the definition of strategies of precision irrigation, in order to optimize crop water productivity and to maximize the economic benefits without affecting environmental quality.Water saving management strategies, such as regulated deficit irrigation (RDI), can be effectively applied if supported by the real time control of soil/plant water status allowing the identification of appropriate irrigation scheduling parameters (irrigation timing and doses). This challenge can be achieved by integrating sensing technologies, internet of things and cloud computing supported with co…
Subsurface Drip Irrigation and ICT for the Innovative Irrigation Water Management: Application to a Citrus Crop (C. reticulata cv. Tardivo di Ciaculli)
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…
Identifying the threshold of soil water content for the precise irrigation scheduling of a Citrus orchard under subsurface drip irrigation
Proper irrigation scheduling requires the knowledge of the soil-plant-atmosphere system, including the relationships existing between its various components. During the last decade, the monitoring of soil water content (SWC) has been considered a standard way to determine when crops need to be irrigated. However, under drip irrigation systems in which laterals are laid on the soil surface or buried at a certain depth, the gradients of soil water content are rather high and therefore the threshold of SWC below which crop water stress occurs should account for the position of the sensors; the threshold, in fact, depends on the specific crop system, as well as on the relative position of the m…