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Derinkuyu dry bean irrigation planning in semi-arid climate by utilising crop water stress index values

Uçak Ali B., Atılgan Atılgan, Korytowski Mariusz, Kocięcka Joanna, Liberacki Daniel, Stachowski Piotr, Saltuk Burak, Rolbiecki Roman

Journal of Water and Land Development

2023

no. 59

145--152

This study was conducted to determine crop water stress index (CWSI) values and irrigation timing in the case of Derinkuyu dry bean (Phaseolus vulgaris L.). In 2017, dry beans were grown as the main crop according to the field design consisting of plots divided into randomised blocks. Irrigation treatment comprised full irrigation (I100) and irrigation issues with three different levels of water stress (I66, I33, I0). This study applied 602 mm of water under the I100 irrigation. The yield of Derinkuyu dry beans was equal to 3576.6 kg∙ha-1 in I100 irrigation. The lower limit (LL) value, which is not necessary for the determination of CWSI, was obtained as the canopy-air temperature difference (Tc - Ta) versus the air vapour pressure deficit (VPD). The upper limit (UL) value, at which the dry beans were wholly exposed to water stress, was obtained at a constant temperature. The threshold CWSI value at which the grain yield of dry beans started to decrease was determined as 0.33 from the measurements made with an infrared thermometer before irrigation in I66 irrigation treatment. As a result, it can be suggested that irrigation should be applied when the CWSI value is 0.33 in dry beans. Furthermore, the correlation analysis revealed a negative correlation between grain yield and crop water stress index and a positive correlation between yield and chlorophyll content. According to variance analysis, significant relationships were found between the analysed parameters at p ≤ 0.01 and p ≤ 0.05.

Defining Irrigation Scheduling Based on Crop Water Stress Index and Physiological Parameters for Hybrid Corn in Semi-Arid Climate

Ucak Ali Beyhan, Saltuk Burak, Rolbiecki Roman, Atilgan Atilgan

Rocznik Ochrona Środowiska

2022

Tom 24

231--245

The goal of this study is to determine the crop water stress index (CWSI) and irrigation scheduling based on CWSI values, as well as to examine the correlations between CWSI, physiological parameters and grain yield of hybrid corn P31A34 in semi-arid climate conditions. In 2014 and 2015, the upper limit (UL) temperatures at which plants were entirely exposed to water stress were 1.178°C and 2.38°C, respectively. When the corn grain yield began to decline, the CWSI threshold value was 0.34, indicating the yield limit. Grain yield, crop water consumption, crop water stress index, chlorophyll content, water use efficiency and leaf area index were found to have negative correlations (p ≤ 0.01) with CWSI values in both years of the study. The findings revealed that in semi-arid climate conditions, a maximum of 30% water deficit could be used during the growing period of the corn compared to full irrigation (I100) for water savings and that a water deficit greater than 30% results in considerable grain yield losses. In areas with limited water resources, the moderate water deficit (I70) may be a viable alternative to the I100.

Comparasion of Crop Water Stress Index (CWSI) and Water Deficit Index (WDI) by using Remote Sensing (RS)

Tanriverdi C., Atilgan A., Degirmenci H., Akyuz A.

Infrastruktura i Ekologia Terenów Wiejskich

2017

nr III/1

879--894

Drought, water scarcity and climate changes are very important threats for agriculture on a global basis. Remote Sensing (RS) is accepted as a technique to collect data and determine water stress indices. Water Stress Indices (WSI) are useful tools to prevent drought and determine irrigation scheduling. The water stress indices are primarily identified as the Crop Water Stress Index (CWSI) and the Water Deficit Index (WDI). The effect of soil background is major problem to establish CWSI especially during early growth stage measurements of canopy temperature (Ts). Hence, WDI is a better index when it comprised with CWSI because of Ts. CWSI and WDI can be determined by two different techniques. These are determined by using measured by using traditional components to collect data and estimated methods by applying RS components to collect necessary data. Estimated method has many advantages when this method compared with measured method. However, estimated method needs some RS components which are infrared gun (IR), sling psychrometer, Spectro radiometer. With the help of these tools, the necessary data are obtained and WDI is determined. By using Spectro radiometer vegetation indices are defined. Among the many vegetation indices, the Normalized Difference Vegetation Index (NDVI) is mostly used one. By using NDVI determination of vegetation cover is easy and accurate technique to establish WDI. Establishing these both stress indices with less fieldwork and by saving money, time and labor conveys the necessary information for agriculturists using remotely sensed data especially for large agricultural fields.