Laser Land Levelling for Higher Water Productivity in Rice-Wheat System

Abstract

Awareness of water conservation has been increasing and understandings of conservation technologies have made headway in the world agriculture. Enhancement in water productivity has been the key objective of planners and the stakeholders. Many water conservation techniques or technologies help in enhancing the water productivity also prevent salt build-up and land degradation. Laser land levelling is one of the many such techniques, which has popularized to a certain extent. Yet its spread has not been significant. Realizing the potential of laser land levelling, the ICAR-Central Soil Salinity Research Institute (ICAR-CSSRI), Karnal, Haryana, India had imported a laser operated land leveller some three decades back. Few research and field evaluation studies have been made in the context of on-farm water savings as well as to judge the impact of this technology on small and marginal farmers. The present study highlights an on-farm as well as observations made in the farmers’ fields, on the basis of scientific observations of information collected at the ICAR-CSSRI farm on the smoothness of the soil surface achieved, uniformity of soil moisture distribution, water requirement for irrigation, as well as saving of time yield differentials of the crops in conventionally levelled and laser levelled fields. A total of 19 farmers’ fields were studied in Pundrak, Zarifa and Kalayat villages in Haryana besides two controlled studies at ICAR-CSSRI farm, Karnal. The values of Levelling Index (LI) for before and after conventional levelling have been evaluated as 3.0 cm and 2.1 cm respectively, whereas in the laser levelled fields, these were 1.93 cm and 0.85 cm respectively. The application time for irrigation in laser levelled fields has reduced to 3.5-4.5 hours from about 6 hours required in conventionally levelled fields for 0.4 ha (1 Acre). The average values of water productivity in conventional and laser-levelled fields have been evaluated at 1.5 and 2.4 kg/m3, respectively for wheat and 0.4 and 0.5 kg/m3 respectively for rice. For the fields having LI of 0.75 cm, the application efficiency has been as high as 90% in comparison to 45% for the field having LI of 6.75 cm. The estimated net profit ranged Rs. 1000 – 1200 for the first year, which rose to Rs. 4000 – 5000 in the second year onwards, during the study for the laser levelled fields. Besides the technical appraisal, the paper highlights the limitations such as necessity of repeat application of laser land levelling once in three years. Fortunately more than 500 custom hiring units have already appeared in the North Indian states due to sensitization through trainings and demonstrations of this technology.