Characterization of Wind Profile over Wheat and Mustard Canopies under Sole and Intercropped Conditions in Lower Gangetic Plain of Eastern India

Abstract

Aim: Wind profile over a crop canopy affects several physiological processes. The nature of the wind profile above the crop canopy of a single crop has been reported in the literature. However, under intercropping system, the nature of wind profile isn’t well discussed.
 Methodology: With this background, a two-year experiment was conducted with five different crop combinations (T1- sole wheat, T2- sole mustard, T3- two wheat: six mustard, T4- four wheat: four mustard and T5- six wheat: two mustard) in Rndomized Block Design (RBD) of 54 m2 plot size. Wind speed was measured at 0.5, 1.0 and 1.5 m above the crop canopy from 9:30 to 13:30 hour at two-hour interval. The observations were taken from 30 to 80 days after emergence (DAE) at weekly interval.
 Results: Results showed that the wind speed gradually increased with the increment of height over the sole wheat. Wind speed sharply declined under intercropping over the wheat canopy. The percentage reduction in T3 was maximal on 58 DAE. The wind speed gradually increased with height for all observations in mustard irrespective of treatment combinations. However, under intercropping, wind speed reduced marginally at 0.5 m above mustard height compared to the sole mustard.
 Conclusion: Reduced wind speed over wheat canopy causes reduction of mass and momentum transfer thus reducing the carbon exchange rate which might be one of the reasons for lower biomass production in wheat-mustard intercrop in comparison to sole wheat crop.