Irrigation water consumption modelling of a soilless cucumber crop under specific greenhouse conditions in a humid tropical climate

Abstract

The irrigation water consumption of a soilless cucumber crop under greenhouse conditions in a humid tropical climate has been evaluated in this paper in order to improve the irrigation water and fertilizers management in these specific conditions. For this purpose, a field experiment was conducted. Two trials were carried out during the years 2011 and 2014 in an experimental farm located in Vinces (Ecuador). In each trial, the complete growing cycle of a cucumber crop grown under a greenhouse was evaluated. Crop development was monitored and a good fit to a sigmoidal Gompertz type growth function was reported. The daily water uptake of the crop was measured and related to the most relevant indoor climate variables. Two different combination methods, namely the Penman-Monteith equation and the Baille equation, were applied. However, the results obtained with these combination methods were not satisfactory due to the poor correlation between the climatic variables, especially the incoming radiation, and the crop's water uptake (WU). On contrary, a good correlation was reported between the crop's water uptake and the leaf area index (LAI), especially in the initial crop stages. However, when the crop is fully developed, the WU stabilizes and becomes independent from the LAI. A preliminary model to simulate the water uptake of the crop was adjusted using the data obtained in the first experiment and then validated with the data of the second experiment.

Soilless Cucumber Cultivation under Protective Structures in Relation to Irrigation Coupled Fertigation Management, Economic Viability and Potential Benefits-A Review

“…Fertigation in soilless cultivation provides efficient use of water and nutrients (Jensen 1997) through precise and uniform application of nutrients directly to the active root system of the plant (Rouphael et al, 2008). Numerous researchers studied the effect of irrigation amount (Mao et al, 2003;Amer et al, 2009;Salcedo et al, 2017) and fertilizer coupled irrigation i.e. fertigation (Papadopoulos 2001;Lee et al, 2005;Ahmet et al, 2006;Zhang et al, 2011) on cucumber yield and water use efficiency (WUE).…”

“…Grewal et al, (2011) confirmed a 33.0% reduction in potable water used for irrigation in hydroponic cucumber production while investigating the opportunities in recycling drainage water to increase water and nutrient-use efficiency and reduce the environmental impact of the drainage water discharge. Salcedo and Reca (2017) reported a good correlation between the crop water uptake (WU) and the leaf area index (LAI) while evaluating the irrigation water consumption of a soilless cucumber crop under greenhouse conditions under a humid tropical climate in order to improve the irrigation water and fertigation management.…”

Estimativa Da Evapotranspiração De Referência Para Botucatu-Sp Por Meio De Modelos De Regressão

“…Um lisímetro consiste, basicamente, de um tanque cilíndrico preenchido com solo e coberto com vegetação, onde é monitorado, com precisão, o balanço hídrico (precipitação, drenagem e evapotranspiração) (SANCHEZ et al, 2017). No entanto, como são equipamentos de elevado aporte financeiro e de difícil operação, é mais comum a obtenção do valor da evapotranspiração por meio de modelos de estimativa, sendo o modelo de Penman-Monteith (PM) o mais aceito e recomendado na literatura (CAPORRUSSO;ROLIM, 2015;SALCEDO et al, 2017), pois incorpora aspectos de balanço de energia e transferência de massa (YAN et al, 2019).…”