Search results for "Water stress function"
showing 7 items of 7 documents
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…
Modeling olive orchard response to water stress and definition of critical thresholds of soil water status.
2011
Improvement of FAO-56 Model to Estimate Transpiration Fluxes of Drought Tolerant Crops under Soil Water Deficit: Application for Olive Groves
2014
[EN] Agro-hydrological models are considered an economic and simple tool for quantifying crop water requirements. In the last two decades, agro-hydrological physically based models have been developed to simulate mass and energy exchange processes in the soil-plant-atmosphere system. Although very reliable, because of the high number of required variables, simplified models have been proposed to quantify crop water consumes. The main aim of this paper is to propose an amendment of the Food and Agricultural Organization (FAO) of the United Nations FAO-56 spreadsheet program to introduce a more realistic shape of the stress function, valid for mature olive orchards (Olea europaea L.). The mod…
Modelling eco-physiological response of table olive trees (Olea europaea L.) to soil water deficit conditions
2013
Abstract The knowledge of crop response to water stress is crucial to predict transpiration reductions under limited soil water conditions and for a rational scheduling of irrigation. In order to assess whatever water stress model, it is necessary to estimate critical thresholds of soil water status, below which plant transpiration starts to decrease. The main objective of the work is to identify the shape and to determine the parameters of table olive orchards (Olea europaea, var. Nocellara del Belice) water stress function, assessed according to relative transpiration or leaf/stem water potential. In order to assess different water stress functions describing the eco-physiological field r…
Assessing AQUACROP water stress function to evaluate the transpiration reductions of olive tree.
2012
Quantitative evaluation of the drought adaptation processes of crops is an important prerequisite for efficient irrigation management. Modeling the plant response under water stress conditions is crucial to identify the exact irrigation timing. Assessment of any water stress function requires the knowledge of its shape and then the estimation of critical thresholds of the soil water status, below which a strong reduction of plant transpiration occurs. In this work, the macroscopic approach is used to assess the water stress function implemented in AQUACROP for mature olive tree. In particular, after discussing about the function shape, the critical thresholds of soil water status are propos…
Using field measurements and FAO-56 model to assess the eco-physiological response of citrus orchards under regulated deficit irrigation
2017
[EN] Micro-irrigation is considered one of the most efficient water distribution systems and allows increasing water use efficiency if coupled with effective water-saving irrigation management strategies as regulated deficit irrigation (RDI) or partial root-zone drying (PRD) techniques. However, application of these strategies makes it crucial the real-time monitoring of soil and crop water status, in order to identify appropriate irrigation scheduling parameters (irrigation timing and doses) and to prevent irreversible damage of plant system and/or crop yield reductions. Even if midday stem water potential (MSWP) is considered one of the most affordable indicator for direct determinations …