Laser Land Levelling
Introduction
Farmers traditionally have been practicing land leveling in their fields by using animal drawn or tractor drawn levelers. These levelers are simple implements consisting of a blade and a small bucket for shifting the soil from higher spot to the low-lying positions. Traditionally leveled or unleveled lands lead to water logging conditions at low lying areas and less soil moisture in higher levels. Significant amount (10-25%) of irrigation water is lost during application at the farm due to poor management and uneven fields.
Excessive irrigation at low lying areas leaches soluble nutrients from the crop root zone and makes the soil less productive. On the other hand, germination and crop stand are affected adversely by low soil moisture at higher levels. Technological Options for Enhanced Productivity and Profit 183 Precision land leveling is expected to enhance water use efficiency and consequently harness higher water productivity.
Precision land leveling helps in controlling the emergence of salt affected patches, increasing cropping intensity and crop productivity in cultivable land area by 3-5 per cent, improving the crop establishment, reducing the weed intensity and saving the irrigation water. Laser leveling is the process of smoothening the land surface ± 2 cm from its average elevation by using laser equipped drag buckets to achieve precision in land leveling.
Precision land leveling involves altering the fields in such a way as to create a constant slope of 0 to 0.2%. This practice makes use of large horsepower tractors and soil movers that are equipped with global positioning systems (GPS) and/or laser-guided instrumentation so that the soil can be moved either by cutting or filling to create the desired slope/level.
Components of laser land leveling system
The laser leveler involves the use of laser (transmitter) that emits a rapidly rotating beam parallel to the required field plane, which is picked up by a sensor (receiving unit) fitted to a tractor towards the scraper unit. The signal received is converted into cut and fill level adjustment and the corresponding changes in the scraper level are carried out automatically by a hydraulic control system. The scraper guidance is fully automatic; the elements of operator error are removed allowing consistently accurate land leveling. The setup consists of two units. The transmitter is a laser, which is mounted on a high platform. It rapidly rotates, sends the laser light in a circle like a lighthouse does, except that the light is a laser, so it remains in a very narrow beam.
A laser controlled land leveling system consists of five major components:
(i) Drag bucket
(ii) Laser transmitter
(iii) Laser receiver
(iv) Control box, and
(v) Hydraulic system
Benefits
Laser controlled precision land leveling helps in Improving crop establishment.
Improving uniformity of crop maturity.
Increasing approximately 3 to 5% of cultivable land area.
Increasing water-application efficiency potential up to 50%.
Increasing cropping intensity up to 40%.
Increasing yield of crops (wheat 15%, sugarcane 42%, rice 61% and cotton 66%).
Controlling the emergence of salt affected patches in the soil.
Saving irrigation water by approximately 35-45%.
Reducing weed problems and improving weed control efficiency
Limitations of laser levelling –
High cost of the equipment/laser instrument.
Need for skilled operator to set/adjust laser settings and operate the tractor.
Less suitable for uneven and undulated fields
For further information please contact :
Indian Agricultural Research Institute,
New Delhi,
Delhi 110012