The experimental research on establishment of the soil water retention curves (pF) in order to determine water content and suitable irrigation amount for dry crops at the droughty region of the southern central part of Vietnam

The correlation result of the experimental research on establishing the soil water retention curves (pF) at the drought region of the Southern Central part of Vietnam has been closely (R2 from 0.96÷0.99). The calculated results of soil water capacity show that the rate of total available soil water compared with field capacity is fairly high, from 76.20% (soil layer 0÷10cm) to 80.68% (the whole layer 0÷60cm). Average of feature moisture content of the layer (0 ÷ 60cm): Saturated moisture (θbh): 34.49% volume, field capacity (θfc): 21.02% volume, wilting moisture (θwp): 4.06% volume. Correlation analysis and establishment of the linear regression equation between: the soil water retention curves (pF) and soil water content, calibration results are suitable with high correlation coefficient, linear regression functions have been built accordingly and overall deductive meaning. The experimental results and calculations are very important in order to apply in determining soil moisture process through measuring equipments and the appropriate irrigation water amount for popular dry crops at the droughty region of the Southern Central Part of Vietnam.

1. Introduction

2. Theoretical basic, objectives, research content and methods

2.1 Theoretical basis

2.2 Research objectives

2.3 Research contents

2.4. Research approach and Methods

3. Results and discussion

3.1. Description of the soil profile and test of soil physical and chemical properties

3.2. The water retention curve (pF curve)

3.3 Available water of the soil and readily available water for crops

3.4 Correlation and linear regresstion between the water retention curve and water amount in the soil (TAWpF1.5 and TRAWpF)

4. Conclusion

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► See detail:  The experimental research on establishment of the soil water retention curves (pF) in order to determine water content and suitable irrigation amount for dry crops at the droughty region of the southern central part of Vietnam

Tran Thai Hung, Vo Khac Tri, Le Sam
Southern Institute of Water Resources Research (SIWRR)

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