Search results for "Irrigation"
showing 10 items of 342 documents
Determination of Evapotranspiration and Crop Coefficient of Cactus Pear (Opuntia ficus-indica Mill.) with an Energy Balance Technique
2013
A micrometeorological approach based on surface renewal technique was adopted to estimate evapotranspiration fluxes and crop coefficient data from an irrigated cactus pear (Opuntia ficus-indica Mill.) orchard under Mediterranean climatic conditions. High-frequency temperature readings were taken above the canopy top in order to get surface renewal sensible heat flux values (HSR). These values were compared against eddy covariance sensible heat fluxes (HEC) for calibration. Latent heat flux (or evapotranspiration, ET) was obtained as the residual of the energy balance equation using HSR. In field measurements of biophysical crop features, physiological characteristic and soil hydraulic compo…
Effects of cropping systems and irrigation on the bio-agronomic and quality response of industrial tomato (Lycopersicon esculentum mill.).
2012
This paper shows the results obtained in 2009 of a study carried out by the Dipartimento di Agronomia Ambientale e Territoriale (D.A.A.T.) aimed at identifying and evaluating various low input cropping systems for industrial tomato varieties, a traditional farming crop in Sicily. The tests were carried out on the Sparacia experimental farm (Cammarata AG, 37°37’N, 13°42’E). The farm is located in a sub-arid area with average rainfall levels of approx. 500 mm and average min/max temperatures of 9 and 21°C. The soils, typical of soil types in the area, are Eutric Vertisols. A split-split plot design with three repetitions was adopted and the following variables were studied: 1) management of c…
Performance of a Pilot-Scale Constructed Wetland and Medium-Term Effects of Treated Wastewater Irrigation of Arundo donax L. on Soil and Plant Parame…
2021
On marginal lands in the Mediterranean basin, giant reed (Arundo donax L.) represents one of the most interesting perennial crops due to high levels of biomass production. Considering periodic water shortage during the summer months in this area, the reuse of treated wastewater (TWW) would seem to be a good opportunity for the growth of the species. The aim of this study was to assess the medium-term effects of irrigation using freshwater (FW) and TWW on soil characteristics and growth in giant reed plants. TWW was obtained from a pilot-scale horizontal subsurface flow constructed wetland system (HSSF CWs) with a total surface area of 100 m2. A split-plot design for a two-factor experiment …
Detecting crop irrigation status in orchard canopies with airborne and ASTER thermal imagery
2007
This work provides a description of the research conducted to assess if ASTER satellite data enable the detection of the water status in orchard tree crops. Summer and winter TERRA-ASTER images were acquired over a study area of Seville in southern Spain over a 6-year period. 1076 olive orchards were monitored in this area, obtaining field location, area, tree density, and irrigation status information. Surface temperature images were obtained using the TES method and 0.5 m resolution panchromatic ortho-rectified imagery collected over the entire area to obtain vegetation cover. A comparison study of the temperature difference between orchards under different irrigation schemes is presented…
Assessing Hydrus-2D to Simulate Soil Water Content (SWC) and Salt Accumulation Under an SDI System: Application to a Potato Crop in a Semi-Arid Area …
2015
In this paper the suitability of the HYDRUS-2D model to simulate volumetric soil water content in the root zone of a potato crop under subsurface drip irrigation (SDI) is initially assessed on the basis of a field study. Then, considering that the crop is moderately sensitive to soil salinity, the model is tested to predict the salt distribution around a buried emitter, when two different water qualities (i.e. electrical conductivity of 1.0 and 4.0 dS m-1) are used during the growing season (treatments T1 and T2). Finally, the soil volume in which salt accumulates is distinguished by the model for the two treatments, for which the respective yields are not significantly different. The resul…
Sowing date, transplanting, plant density and nitrogen fertilization affect indigo production from Isatis species in a Mediterranean region of Spain
2006
Abstract The increasing interest in natural products from a renewable source has encouraged growers to reintroduce indigo-producing crops into the European agriculture. We studied agronomic conditions (sowing date, plant density, nitrogen fertilization, irrigation rate, seedling transplanting) influencing production of the blue pigment indigo, from Isatis tinctoria and I. indigotica crops in a Mediterranean region of Spain (Valencia). I. tinctoria was more suitable for cultivation in our climate conditions than I. indigotica . Indigo yield from Spanish I. tinctoria trials was greater than in Northern and Central Europe. Furthermore, indigo production was maintained when water and nitrogen s…
Irrigation water intensity and climate variability: an agricultural crops analysis of Italian regions
2020
This paper examines the relationship between the requirement of water resources for irrigation and climate variability and analyses the ranking of the best and worst performance of irrigation water intensity for each Italian region. To measure water resources demanded by agriculture, the irrigation water intensity (IWI) indicator has been computed as the ratio between volumes of irrigation water and total crop harvested. By applying panel data methodologies to a regional dataset spanning from 2000 to 2009, we may address heterogeneity and omitted variable issues. By merging meteo-climatic with agricultural variables, we may confirm that water precipitations, maximum temperature, irrigation …
La intervención de la Junta de Comercio de Valencia en la política arrocera de la monarquía en la segunda mitad del siglo XVIII: los informes emitido…
2005
El análisis de los informes emitidos por la Junta de Comercio de Valencia en la segunda mitad del siglo XVIII revela la influencia que tuvo la institución en la conformación de la política arrocera de la monarquía. Al igual que ésta, su posición evolucionó desde la hostilidad hacia el cultivo del arroz en la etapa inicial de su intervención hasta la defensa de sus ventajas en la década de 1790. Los argumentos esgrimidos en ambos sentidos permiten identificar los intereses económicos que condicionaron sus planteamientos. Igualmente, el análisis del marco socioeconómico en el que se insertaba la institución contribuye a explicar las razones de la evolución experimentada. The analysis of the r…
E.O.-based estimation of transpiration and crop water requirements for vineyards: a case study in southern Italy
2014
An efficient use of water for irrigation is a challenging task. From an agronomical point of view, it requires establishing the optimal amount of water to be supplied, at the correct time, based on phenological phase and water stress spatial distribution. Indeed, the knowledge of the actual water stress is essential for agronomic decisions, vineyards need to be managed to maintain a moderate water stress, thus allowing to optimize berries quality and quantity. Methods for quickly quantifying where, when and in what extent, vines begin to experience water stress are beneficial. Traditional point based methodologies, such those based on Scholander pressure chamber, even if well established ar…
Elimination of cyanobacteria and microcystins in irrigation water—effects of hydrogen peroxide treatment
2020
AbstractCyanobacterial blooms pose a risk to wild and domestic animals as well as humans due to the toxins they may produce. Humans may be subjected to cyanobacterial toxins through many routes, e.g., by consuming contaminated drinking water, fish, and crop plants or through recreational activities. In earlier studies, cyanobacterial cells have been shown to accumulate on leafy plants after spray irrigation with cyanobacteria-containing water, and microcystin (MC) has been detected in the plant root system after irrigation with MC-containing water. This paper reports a series of experiments where lysis of cyanobacteria in abstracted lake water was induced by the use of hydrogen peroxide and…