Regional evapotranspiration rate of oasis and surrounding desert

2012 ◽  
Vol 27 (24) ◽  
pp. 3409-3414 ◽  
Author(s):  
Jihong Jia ◽  
Wenzhi Zhao ◽  
Shoubo Li
Keyword(s):  
Evapotranspiration Rate ◽  
Regional Evapotranspiration

A simple numerical model to estimate water availability in saline soils

Soil Research ◽  
2018 ◽  
Vol 56 (3) ◽  
pp. 264 ◽  
Author(s):  
Mohammad Hossein Mohammadi ◽  
Mahnaz Khataar
Keyword(s):  
Numerical Model ◽  
Water Content ◽  
Soil Water ◽  
Water Uptake ◽  
Soil Salinity ◽  
Irrigation Water ◽  
Weighting Function ◽  
Water Salinity ◽  
Irrigation Water Salinity ◽  
Evapotranspiration Rate

We developed a numerical model to predict soil salinity from knowledge of evapotranspiration rate, crop salt tolerance, irrigation water salinity, and soil hydraulic properties. Using the model, we introduced a new weighting function to express the limitation imposed by salinity on plant available water estimated by the integral water capacity concept. Lower and critical limits of soil water uptake by plants were also defined. We further analysed the sensitivity of model results to underlying parameters using characteristics given for corn, cowpea, and barley in the literature and two clay and sandy loam soils obtained from databases. Results showed that, between two irrigation events, soil salinity increased nonlinearly with decreasing soil water content especially when evapotranspiration and soil drainage rate were high. The salinity weighting function depended greatly on the plant sensitivity to salinity and irrigation water salinity. This research confirmed that both critical and lower limits (in terms of water content) of soil water uptake by plants increased with evapotranspiration rate and irrigation water salinity. Since the presented approach is based on a physical concept and well-known plant parameters, soil hydraulic characteristics, irrigation water salinity, and meteorological conditions, it may be useful in spatio-temporal modelling of soil water quality and quantity and prediction of crop yield.

scholarly journals Comparison of Aerodynamic, Bowen-Ratio, and Penman-Monteith Methods in Estimating Evapotranspiration of Oil Palm Plantation

Agromet ◽  
2018 ◽  
Vol 32 (1) ◽  
pp. 11
Author(s):  
Tania June ◽  
Ni Wayan Srimani Puspa Dewi ◽  
Ana Meijide
Keyword(s):  
Oil Palm ◽  
Economic Value ◽  
Global Radiation ◽  
Reference Method ◽  
Bowen Ratio ◽  
Ratio Method ◽  
Agricultural Commodity ◽  
Evapotranspiration Rate ◽  
Oil Palms

<p>Oil palm is one important agricultural commodity that has high economic value. Oil palm productivity is significantly influenced by its water use (needs). Measurement and estimation of oil palm evapotranspiration is needed for determination of its water needs. Various methods are available and this study compare three methods, consisting of aerodynamic, Bowen-Ratio and Penman-Monteith methods in analyzing water needs/use of oil palms plantation located in PTPN VI Jambi.  Peak of evapotranspiration rate occured in the afternoon around 13.00 and 14.00 local time. Bowen-Ratio method has higher estimation value of evapotranspiration than the other two methods. Ratio between evapotranspiration and global radiation of two and ten-years old oil palm plantations remain similar, around 47%. Penman Monteith method has the nearest estimation value to reference method (aerodynamic method) showed by the smallest RMSE value, 0.087 for two years oil palm and 0.157 for ten-years old oil palm.<strong> </strong></p>

scholarly journals A Model of Evapotranspirative Irrigation to Manage the Various Water Levels in the System of Rice Intensification (SRI) and Its Effect on Crop and Water Productivities

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 170
Author(s):  
Chusnul Arif ◽  
Satyanto Krido Saptomo ◽  
Budi Indra Setiawan ◽  
Muh Taufik ◽  
Willy Bayuardi Suwarno ◽  
...  
Keyword(s):  
Water Use ◽  
Water Productivity ◽  
Drainage System ◽  
Efficiency Index ◽  
Water Levels ◽  
System Of Rice Intensification ◽  
Irrigation Regimes ◽  
Evapotranspiration Rate ◽  
Rice Intensification ◽  
Use Efficiency

Evapotranspirative irrigation is a simple idea in a watering field based on the actual evapotranspiration rate, by operating an automatic floating valve in the inlet without electric power to manage water levels. The current study introduces a model of evapotranspirative irrigation and its application under different water levels. The objectives were (1) to evaluate the performances of evapotranspirative irrigation under various irrigation regimes, and to (2) to observe crop and water productivities of the system of rice intensification (SRI) as affected by different types of irrigation. The experiment was performed during one rice planting season, starting from July to November 2020, with three irrigation regimes, i.e., continuous flooded (CFI), moderate flooded (MFI) and water-saving irrigation (WSI). Good performance of the system was achieved; low root mean square error (RMSE) was indicated between observed water level and the set point in all irrigation regimes. Developing a better drainage system can improve the system. Among the regimes, the WSI regime was most effective in water use. It was able to increase water productivity by up to 14.5% while maintaining the crop yield. In addition, it has the highest water-use efficiency index. The index was 34% and 52% higher than those of the MFI and CFI regimes, respectively. Accordingly, the evapotranspirative irrigation was effective in controlling various water levels, and we recommend the system implemented at the field levels.

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