Search results for "Crop coefficient"
showing 8 items of 18 documents
Assessing crop coefficients of sunflower and canola using two-source energy balance and thermal radiometry
2014
Abstract A new technique for the local adjustments in crop coefficients is presented. This is an alternative to conventional lysimeter measurements traditionally used for improved irrigation scheduling. The method is based on the combination of a two-source energy balance model and local measurements of radiometric temperatures. Two experimental campaigns were carried out on sunflower and canola in a cropland area located in Barrax, Albacete, in the summer of 2011 and spring of 2012, respectively. Radiometric temperatures of soil and canopy were collected, together with biophysical and meteorological variables. Combining all these data in a two-source energy balance model allowed separation…
Effect of plant species on water balance in a pilot-scale horizontal subsurface flow constructed wetland planted with Arundo donax L. and Cyperus alt…
2015
Abstract In constructed wetland systems (CWs) for wastewater treatment, evapotranspiration (ET) is the most important water balance component in arid and semi-arid regions, where high performance levels are needed when treating contaminants and where it is also vital to preserve as much water as possible for reuse in irrigation. This study shows the results of a series of water balance measurements obtained between 2012 and 2013 from a pilot HSSF system in the West of Sicily (Italy). The system was made by two separate vegetated units: one with Arundo donax L. (giant reed) and the other with Cyperus alternifolius L. (umbrella sedge), and fed with urban wastewater following secondary treatme…
Combined use of eddy covariance and sap flow techniques for partition of ET fluxes and water stress assessment in an irrigated olive orchard
2013
Correct estimation of crop actual transpiration plays a key-role in precision irrigation scheduling, since crop growth and yield are associated to the water passing through the crop. Objective of the work was to assess how the combined use of micro-meteorological techniques (eddy covariance, EC) and physiological measurements (sap flow, SF) allows a better comprehension of the processes involving in the Soil–Plant–Atmosphere continuum. To this aim, an experimental dataset of actual evapotranspiration, plant transpiration, and soil water content measurements was collected in an olive orchard during the midseason phenological period of 2009 and 2010. It was demonstrated that the joint use of …
Determining water use of sorghum from two-source energy balance and radiometric temperatures
2011
Estimates of surface actual evapotranspiration (ET) can assist in predicting crop water requirements. An alternative to the traditional crop-coefficient methods are the energy balance models. The objective of this research was to show how surface temperature observations can be used, together with a two-source energy balance model, to determine crop water use throughout the different phenological stages of a crop grown. Radiometric temperatures were collected in a sorghum (<i>Sorghum bicolor</i>) field as part of an experimental campaign carried out in Barrax, Spain, during the 2010 summer growing season. Performance of the Simplified Two-Source Energy Balance (STSEB) model was …
Updated single and dual crop coefficients for tree and vine fruit crops
2021
Abstract The present study reviews the research on the FAO56 crop coefficients of fruit trees and vines performed over the past twenty years. The main objective was to update information and extend tabulated single (K c ) and basal (K cb ) standard crop coefficients. The selection and analysis of the literature for this review have been done to consider only studies that adhere to FAO56 method, computing the reference ET with the FAO Penman–Monteith ET o equation and field measuring crop ET with proved accuracy. The crops considered refer to vine fruit crops, berries and hops, temperate climate evergreen fruit trees, temperate climate deciduous fruit trees and, tropical and subtropical fru…
Effects of different amendments (organic matter and hydrogel) on the actual evapotranspiration and crop coefficient of turf grass under field conditi…
2020
The irrigation schedule in arid areas has to be efficient in order to reduce losses due to evaporation and deep infiltration. Irrigation optimization poses the need to establish with precision the value of actual evapotranspiration (ETa), and the crop coefficient (Kc). The water soil availability can be increased using hydrogel and organic matter amendments, and their effects could vary ETa and Kc. The aim of this study was to determine the ETa, and Kc of an experimental site with lysimeters on the Spanish Mediterranean coast cropped with a turf grass variety, Agrostis stolonifera ‐L‐93, under field conditions, and amended with hydrogel and organic matter. Reference evapotranspiration (ET0)…
Evaluation of the MOD16A2 evapotranspiration product in an agricultural area of Argentina, the Pampas region
2021
The Pampas Region is a big plain of approximately 520,000 km2 in Argentina. It is essential to estimate evapotranspiration (ET) in this region since the primary productivity is directly linked to water availability. Information provided by satellite missions allows monitoring the spatial and temporal variability of ET. In the current study, we evaluated the version 006 of MOD16A2 product (MOD16A2.006) of Potential Evapotranspiration (ETp) and Actual Evapotranspiration (ETa) in Argentinian Pampas Region (APR). MOD16A2.006 product was compared with Crop Evapotranspiration (ETc), calculated with local measurements from the Oficina de Riesgo Agropecuario (ORA), and Crop Coefficient (Kc) data (f…
EVAPOTRANSPIRATION, CROP COEFFICIENTS AND WATER USE EFFICIENCY OF CYPERUS ALTERNIFOLIUS L. AND TYPHA LATIFOLIA L. IN A PILOT-SCALE HORIZONTAL SUBSURF…
2014
In constructed wetland systems (CWs) for wastewater treatment, the efficiency of the system is highly affected by the system’s water balance. This study shows the results of a series of water balance measurements obtained in 2013 from a pilot horizontal-subsurface flow (HSSF) system in the West of Sicily (Italy). The system included three separate units, one planted with Cyperus alternifolius L., one planted with Typha latifolia L. and an unplanted unit. The system was fed with urban wastewater from an activated-sludge wastewater treatment plant. The aim of the study was to compare evapotranspiration rates (ET), crop coefficients (Kc) and water use efficiency (WUE) of two root emergent macr…