Laser Land Levelling

 What is laser land levelling?

 

Land leveller in pictorial form

Example sketch of laser land levelling

 

Laser leveling is a process of smoothing the land surface (± 2 cm) from its average elevation using laser-equipped tractor-pulled scrapers. This practice uses 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. This technique is well known for achieving higher levels of accuracy in land leveling and offers great potential for water savings and higher crop yields.

What are the benefits of laser land leveling?

Unlevelled field

Levelled field

 

Levelled field

Levelled field

◊ Leveled fields have more uniform soil moisture, resulting in more uniform germination and improved crop yield.

◊ Laser leveling improves irrigation efficiency and conserves water.

◊ Improved irrigation efficiency reduces nutrient loss.
◊ Planting is more uniform, which helps achieve higher yields.
◊ Land leveling reduces weed, pest, and disease problems.
◊ Improves operational efficiency (reducing operating time by 10% to 15%).
◊ Reduced costs by reducing consumption of seeds, fertilizers, chemicals and fuel.
◊ Operate agricultural machinery at higher speeds across leveled fields.

 

 

How does a laser level work?


A laser transmitter transmits a laser beam, which is intercepted by the laser receiver mounted on the scraper. The control panel mounted on the tractor interprets the signal from the receiver and opens or closes the hydraulic control valve, which will raise or lower the scraper. Loose soils are picked up by the scraper and released lower in the field.

4-wheel tractor – A 4-wheel tractor is required to pull the scraper. The size of the

Land leveller and tractor

Land leveller and tractor

tractor can
vary from 30-500 hp, though a 4 wheel drive with
power shift transmission is preferable.

Scraper – The scraper can be either 3-point linkage mounted or pulled by the tractor’s drawbar. Pull type systems are preferred for better weight distribution and strength.

Laser transmitter – The laser transmitter mounts on a tripod which allows the laser beam to sweep above the tractor unobstructed. With the plane of light above the field, several tractors can work from one transmitter.

Laser receiver – The laser receiver detects the position of the laser reference plane and What is laser land leveling_page3_image15transmits these signals to the control box. The receiver mounts on a mast attached to the scraper.

Control panel – The control box accepts and processes signals from the machine-mounted receiver. It then indicates the scraper’s position relative to the finished grade.

Hydraulic control system – The tractor’s hydraulic pump system supplies oil to operate the scraper.

Oil control system

Oil control system

 

What is the procedure for laser leveling?

Laser leveling requires soil to be shifted from the high points of the field to the low points in the most cost-effective way. In most situations fields will need to be plowed and a topographic survey undertaken before leveling commences.

Step 1: Plowing the field
The field should be preferably plowed from the center of the field outwards. Plow when the soil is moist, because if it is plowed dry a significant increase in tractor power is required and large clod sizes may result. Cut up or remove surface residues to aid soil flow from the bucket.

Step 2: Conducting a topographic survey

Once the field is plowed, a topographic survey should be conducted to record the high and What is laser land leveling_page3_image17low spots in the field. The mean height of the field can be calculated by taking the sum of all the readings and dividing by the number of readings taken. Then, using a field diagram and the mean height of the field, determine how to effectively move soil from the high to low areas.

 

 

Step 3: Leveling the field
Leveling a field involves the following steps:
• The laser-controlled scraper should be positioned at a point that represents the mean height of the field.
• The cutting blade should be set slightly above ground level (1-2 cm). The tractor should then be driven in a circular direction from the high areas to the lower areas in the field.
• To maximize working efficiency, as soon as the scraper is near filled with soil the operator should turn and drive towards the lower area. Similarly, when the scraper is near empty the tractor should be turned and driven back to the higher areas.
• When the whole field has been covered, the tractor and scraper should then do a final leveling pass in long runs from the high end of the field to the lower end.
• Re-survey to make sure that the desired level of precision has been attained.

The best tool for the job of land levelling in Africa is an IMC Scraper.  The scraper is a specially designed tool that evens out the lumps and bumps in your field.  IMC scrapers are designed to go in containers as shipping farm machinery is most secure if it goes in a container.  Field scrapers are among the most important bits of kit for your farm in Nigeria.  Users of IMC scrapers will testify to the robustness of the machines.

Written by: Fiona Johnson

May 2014