Manual forLaser LandLevelingJ F RickmanNational Agricultural Technology ProjectICARIndian Council of Agricultural ResearchRice-Wheat Consortium for the Indo-Gangetic Plains
Citation: Rickman, J.F., 2002. Manual for laser land leveling, Rice-Wheat Consortium Technical BulletinSeries 5. New Delhi-110 012, India: Rice-Wheat Consortium for the Indo-Gangetic Plains. pp.24.The initial support from the Asian Development Bank and InternationalFund for Agricultural Development provided the groundwork forestablishment of the RWC in 1994 and formalizing the collaborationsbetween the NARS, IARCs and ARIs. The NARS-driven strategicecoregional research initiatives with financial support from theGovernments of the Netherlands, Sweden, Switzerland, Australia andthe US Agency for International Development and the World Bankhave grown over the years into a dynamic agenda of resourceconservation technologies appropriate to different transects of theIndo-Gangetic Plains. The on-going successes in scaling-up resourceconservation technologies for enhancing productivity and sustainabilityof the rice-wheat systems are beginning to create a revolution andfavourably benefit large areas and more numbers of farm families.Cover pictures:Top left: Checking the laser transmitter and receiver communication for actualfield surveyBottom left: Conducting a detailed topographic survey with a laser systemBottom right: Receiver mounted on the mast on a scraper bucket, hitched to atractor, in alignment with the transmitter (laser unit)Background: A diffused view of a laser leveled fieldThe production of this publication has been supported by the National AgriculturalTechnology Project (NATP), Indian Council of Agricultural Research through its SpecialResearch Sub-project on Accelerating the Adoption of Resource Conservation Technologies(RCTs) for Farm-level Impact on Sustainability of Rice-Wheat Systems of the IndoGangetic Plains in the PSR Mode.The designations employed and the presentation of the material in this publication do not imply the expression ofany opinion whatsoever on the part of the Rice-Wheat Consortium for the Indo-Gangetic Plains concerning the legalstatus of any country, person, territory, city or area, or of its authorities, or concerning the delimitations of its frontiersor boundaries. Where trade/proprietary names are used, even in illustrations, this does not constitute endorsementof or discrimination against any product, instrument or machine by the Consortium.
Rice-Wheat Consortium Technical Bulletin Series 5J F RickmanNational Agricultural Technology ProjectIndian Council of Agricultural ResearchRice-Wheat Consortium for the Indo-Gangetic PlainsCG Block, National Agriculture Science Centre (NASC) ComplexDPS Marg, Pusa Campus, New Delhi 110 012, India2002
AuthorJ F Rickman International Rice Research Institute, Los Baños, Philippines
ContentsI. Introduction1II. Why Laser-level Land?1Benefits of Land Leveling1Economics of Land Leveling3Options for Land Leveling4Benefits of Laser Leveling5III. Laser-controlled Land Leveling Systems5How Laser Leveling Works54-wheel Tractor6Plow6Drag Bucket6Laser Transmitter6Laser Receiver6Control Panel7Hydraulic Control System7IV. How to Laser-level Land8Overview8Step 1: Plowing the Field8Step 2: Conducting a Topographic Survey8Step 2.1: Recording Survey Measurements10Step 3: Leveling the Field11Estimating Time Requirements11Measuring Distance11Checking/Calibration of a Laser Transmitter13V. Troubleshooting14Annexure I : Design Specifications of a Typical Drag Bucket16(iii)
Manual forLaser Land LevelingI. IntroductionUnevenness of the soil surface has a majorimpact on the germination, stand and yield ofcrops through nutrient water interaction andsalt and soil moisture distribution pattern. Landleveling is a precursor to good agronomic, soiland crop management practices. Resourceconserving technologies perform better on wellleveled and laid-out fields. Farmers recognizethis and therefore devote considerable attentionand resources in leveling their fields properly.However, traditional methods of leveling landare not only more cumbersome and timeconsuming but more expensive as well. Veryoften most rice farmers level their fields underponded water conditions. The others dry leveltheir fields and check level by ponding water.Thus in the process of a having good levelingin fields, a considerable amount of water iswasted. It is a common knowledge that mostof the farmers apply irrigation water until all theparcels are fully wetted and covered with a thinsheet of water. Studies have indicated that asignificant (20-25%) amount of irrigation wateris lost during its application at the farm due topoor farm designing and unevenness of thefields. This problem is more pronounced in thecase of rice fields. Unevenness of fields leadsto inefficient use of irrigation water and alsodelays tillage and crop establishment options.Fields that are not level have uneven cropstands, increased weed burdens and unevenmaturing of crops. All these factors tend tocontribute to reduced yield and grain qualitywhich reduce the potential farmgate income.Effective land leveling is meant to nt, reduce the irrigation time andeffort required to manage crop. The Manual forLaser Land Leveling seeks to explain thebenefits of land leveling in fields, particularlyrice fields, and help develop skills of farmersand operators in using laser technology toachieve a level field surface. It is also intendedto enable the users to identify and understandthe working of the various components of alaser-controlled land leveling system; undertakea topographic survey using a laser system; setup and use a laser-controlled leveling systemand troubleshoot a laser-controlled levelingsystem. It is hoped that the users (farmers andservice providers) will find this manual usefulin adopting this important resource conservingtechnology as a precursor to several otherimproved agronomic, soil and crop managementpractices.II. Why Laser-level Land?Benefits of Land LevelingEffective land leveling reduces the work in cropestablishment and crop management, andincreases the yield and quality. Level landimproves water coverage thatlllllImproves crop establishmentReduces weed problemsImproves uniformity of crop maturityDecreases the time to complete tasksReduces the amount of water required forland preparationYieldResearch has shown a large increase in riceyield due to good field leveling. The followingtable shows the results of land levelingexperiments conducted in Cambodia between1996 and 1999.1
Table 1. Results of land leveling experiments conductedby CIAP in Cambodia, 1996-1999YearRice Yield (t 72.271.4619982.722.361999 (CARDI)2.342.00Average2.722.19The above table shows that, for the samerice varieties and the same fertilizer input, theaverage increase in crop yield was 24% or530 kg ha–1.In two experiments conducted at differentlocalities, a strong correlation was foundbetween the levelness of the land and cropyield. This correlation is shown in Fig. 1.Fig.2. Manual weeding operation.– a 75% decrease in the labor required forweeding.Farm OperationWeed ControlLand leveling increases yield. A large part ofthis increase is due to improved weed control.Improved water coverage from better landleveling reduces weeds by up to 40%. Thisreduction in weeds results in less time for cropweeding. A reduction from 21 to 5 labor-daysper hectare is achieved. This represents areduction of up to 16 person-days per hectareLand leveling makes possible the use of largerfields. Larger fields increase the farming area(Fig. 3) and improve operational efficiency.Increasing field sizes from 0.1 hectare to 0.5hectare increases the farming area by between5% and 7%. This increase in farming areagives the farmer the option to reshape thefarming area that can reduce operating time by10% to 15%.Fig.1. Graph showing correlation between the levelness of the land and crop yield.2
effectively terraces fields allowing water in thehigher fields to be used in the lower fields(Fig. 4) for land preparation, plant establishmentand irrigation.Economics of Land LevelingFig.3. Larger fields increase the farming area.Seeding PracticesLeveling reduces the time taken for planting,for transplanting and for direct seeding. Landleveling provides greater opportunity to usedirect seeding. The possible reduction in laborby changing from transplanting to direct seedingis approximately 30 person-days per hectare.Efficiency of Water UseRice farmers using animals or 2-wheel tractorsrely on water to accumulate in the field beforestarting land preparation. The averagedifference in height between the highest andlowest portions of rice fields in Asia is 160 mm.This means that in an unleveled field an extra80 mm to 100mm of water must be stored inthe field to give complete water coverage. Thisis nearly an extra 10% of the total waterrequirement to grow the crop. Land levelingFig.4. Land leveling terraces fields allowing water in thehigher fields to be used in the lower fields.The initial cost of land leveling using contractorsand machinery is high. The costs vary accordingto the topography, the shape of the field andthe equipment used. The table below shows acost comparison for leveling one hectare ofland using animals and machines.Table 2. The time and cost comparison for land levelingin eeltractorPurchase price ( )500100012,000Time (days)1270.515.009.002.50Fuel & oil22.0032.50Repairs5.007.50Operating cost ( /ha)LaborPumping cost6.006.00Fixed cost ( /ha)Depreciation cost12.004.007.50Total cost ( /ha)33.0046.0050.00The above table shows that the total costof leveling one hectare of land using tractorsis between 45 and 50. This cost varies withthe volume of soil to be moved and the soiltype. Studies over many sites have shown thatthe actual cost ranges from 3 to 5 per10 mm of soil moved per hectare. Contractorscharge between 30 and 100 per hectare.As the sophistication of the equipmentincreases, so does the capital cost. A 2-meterdrag bucket costs 1,000 to manufacturelocally. A laser-controlled system will costbetween 3,500 and 10,000 to buy. However,using more sophisticated equipment increasesthe area that can be leveled each day.3
The application of additional fertilizer,especially phosphate, is necessary in areasfrom which soil is moved. Depending on thesoil type and the volume of soil moved, it maybe necessary to add an extra 25 to 50kg/ha ofDAP at a cost of between 6 and 13 perhectare.Once a field has been leveled, plowingtechniques must be changed to keep it level.Farmers are encouraged to plow from thecenter of the field out rather than continuing touse the traditional technique of plowing fromthe outside of the field in to the center. Ifappropriate plowing techniques are used, releveling the whole field should not be necessaryfor at least eight to ten years. Measurementstaken in fields in the second and third year afterleveling have shown very little variation insurface topography. The levelness of the fieldhas been maintained after two crops.Financial Benefits of Land LevelingAlthough the initial cost of land leveling is anextra expense, a cash flow over a period ofyears shows that financial benefits do resultfrom land leveling. The table below is a cashflow that outlines the additional cost and benefitsover an eight-year period. The costs allow foran extra plowing and extra fertilizer in the firstand second years. The benefits include reducedweeding costs of 40%.This table shows that there are majorfinancial benefits to be gained through landleveling. What the table does not include arethe other benefits and opportunities of beingable to direct seed, plow the field on time,harvest evenly ripened crop and shedfloodwaters more rapidly.While poor farmers may have problemsfinancing a contractor to level land, it is quitepossible for all farmers to level part of their landeach year using animals and harrows duringthe normal plowing cycle.Options for Land LevelingDraft animals, such as buffaloes and oxen, 2wheel tractors or 4-wheel tractors can all beused as power sources to level a field. Differentsystems require different field conditions andoperating time to complete the task.Table 3. The additional cost and financial benefit fromland levelingYear12345678Additional cost ( 6000000Fig. 5. Leveling field with the help of leveling board pulledby draft animals.Financial benefit ( /ha)Grain yield535353535353535388888888Reductionin weedingCumulativecash flow4-17 3899 160 221 282 343 404lDraft animals and 2-wheel tractors usingharrows and leveling boards. These levelingtechniques require total water coverage ofthe field and require 7 to 8 days for a 2wheeled tractor and 12 days per hectare ofland using draft animals.
l4-wheel tractor using rear mounted tractorblades or drag buckets. 4-wheel tractorsare very effective for leveling both wet anddry fields. Wet fields are best leveled witha rear-mounted tractor blade. Dry fields arebest leveled using hydraulically operateddrag buckets. Tractor work rates aredependent on the tractor’s capacity and theamount of soil to be moved. It takesapproximately 8 hours to level 1 hectarewith a rear mounted tractor blade. Thisreduces to about 4 hours when using adrag bucket.lMore level and smooth soil surfacelReduction in time and water required toirrigate the fieldlMore uniform distribution of water in thefieldlMore uniform moisture environment forcropslMore uniform germination and growth ofcropslReduction in seeds, fertilizer, chemicalsand fuel used in cultural operationslImproved field trafficability (for subsequentoperations)The limitations include the following:lHigh cost of the equipment/laser instrumentlNeed for skilled operator to set/adjust lasers