TEMPORAL VARIABILITY OF LEVELLING INDICES AS INFLUENCED BY DIFFERENT LAND LEVELLING METHODS

P.S. KANANNAVAR¹*, P. BALAKRISHNAN², R.S. CHILUR³, Y. RAVINDRA⁴, MANOJ KUMAR⁵, BASAVARAJ^6
1University of Agricultural Sciences Raichur, Karnataka, India
²University of Agricultural Sciences Raichur, Karnataka, India
³University of Agricultural Sciences Raichur, Karnataka, India
⁴University of Agricultural Sciences Raichur, Karnataka, India
⁵University of Agricultural Sciences Raichur, Karnataka, India
⁶University of Agricultural Sciences Raichur, Karnataka, India
* Corresponding Author : pskanannavar@gmail.com

Received : 17-04-2016     Accepted : 30-04-2016     Published : 01-09-2016
Volume : 8     Issue : 31       Pages : 1655 - 1656
Int J Agr Sci 8.31 (2016):1655-1656

Keywords : Temporal variability, Levelling index, Laser levelling, Conventional levelling
Academic Editor : Srigiri Mallikarjuna, S K Karthik
Conflict of Interest : None declared
Acknowledgements/Funding : Authors are thankful to all the Officers of the University of Agricultural Sciences, Raichur and Dean (Ag. Engg.) and Head and All Staff of Dept. of Soil and Water Engineering, College of Agricultural Engineering for their technical and financial support
Author Contribution : None declared

Land development is one of the prime components of precision farming. Unevenness of agricultural fields leads to the in-efficient use of irrigation water, which in turn reduces the yield and farm income. Levelling index, which is a dynamic factor, determines the quality and accuracy of land levelling. Therefore, it is imperative to study the temporal variability of levelling indices. A field experiment was conducted at two different duration viz., 2009-2010 and 2012-2013 in the research farms of UAS, Raichur, Karnataka state. The study was taken up during the year 2009-10 as first observation to find levelling index of the fields by different methods viz., the conventional levelling and the tractor operated laser guided land leveller. A comparative evaluation of the laser guided land leveller with the conventional system of levelling revealed that, the percentage reduction in standard deviation of reduced levels at grid points of 10X10 m with-in the field for before and after levelling was 85.7 % for laser levelling, and that of 46.79 % for the conventional method which was 38.91 % lower when compared with the laser levelling. The levelling indices before and after conventional levelling were 0.18 m and 0.10 m and the same for before and after laser levelling were 0.17 m and 0.02 m respectively. During the year 2012-13, the levelling indices of the fields levelled by conventional and laser levelling methods were 0.20 m and 0.07 m respectively. The standard deviation of reduced levels for fields levelled by conventional and laser levelling methods were 0.25 m and 0.08 m respectively. Though the temporal variability with respect to levelling indices was observed in both conventional and laser levelled fields, the lesser variations were found in laser levelled field.