Water Management: Towards Sustainable Agriculture (Download PDF)

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In 2018 - 19 food grain production is touching an all-time high record level of 284 plus million tonnes (MT) . Sustainable agriculture is a way of farming. Aims at meeting the needs of present generation.

  • Without endangering the resource base of the future generations.
  • Location specific ecosystem.
  • Study of relationship between organisms and their environment.
  • Sustainable water management in agriculture:
    • Aims to match water availability and water needs in quantity and quality.
    • In space and time.
    • Reasonable cost and acceptable environmental impact.
    • A priority for agriculture in arid and semi-arid regions.
    • Less than 40 % of the applied water is actually used by the crops.
  • Challenging task for India:
    • 17.5 % of the world՚s human population.
    • A meagre 2.3 % of land area.
    • Only 4 % of the global water resources at its disposal.
    • To feed and fodder to 11 % of the world՚s livestock population.
    • Net cultivated area is unlikely to exceed to 143 million hectare in 2050.
    • Estimated rainfed agriculture to cover around 45 % of the net sown area.
    • Target of 355 MT for food grains, 180 MT for vegetables, 182 MT for milk, 15 MT for meat, 16 MT for fish by 2030.

India՚s Food Grain Production in Million Tonnes

India՚s Food Grain Production in Million Tonnes
YearProduction (million tonnes)
2005 - 06208.60
2011 - 12259.29
2019 - 20295.67 (3rd Advance Estimates)

Ways to Sustain Agricultural Productivity

  • Soil management through conservation agriculture, organic farming, integrated nutrient management system and on-farm residue management.
  • Efficient water resource management techniques like right method of irrigation, micro-irrigation, life-saving irrigation, use of mulches etc.
  • Crop management includes right time of sewing, cultivation of suitable crops and varieties in rotation, inter cropping, mixed-cropping, integrated pests management, etc.

Effective Water Management Practices

  • To match water availability and water needs.
  • Maintaining the quantity and quality of water.
  • Space and time.
  • Reasonable cost with acceptable environmental impact.

Irrigation Scheduling

  • When to irrigate.
  • How much to irrigate
  • How to apply water in the field.

A Plethora of Technologies and Practices

  • Focusing on enhanced water use efficiency at all levels.
  • Developed by the National Agricultural Research System (NARS) along with State Agricultural Universities (SAUs) , Indian Council of Agricultural Research (ICAR) institutions and All India Coordinated Research Projects (AICRPs) .

Laser Land Levelling

  • Proper land levelling.
  • Generally ignored by most performers.
  • Increases the water application efficiency.
  • Leads to higher yields as well as rise in water use efficiency.
  • Direct impact on the nutrient use efficiency.
Increment in Crop Productivity and Water Saving through Laser Land Levelling
CropLaser Levelled field

(Grain yield (t/ha) )

Without Laser Levelling field (Grain yield (t/ha) )Water saving over without laser levelled field (%)
Paddy6.796.5038
Wheat4.754.5520
Sugarcane112.0098.7524
Summer mungbean0.550.3820
Potato10.009.0025
Onion10.009.0020
Sunflower2.252.0020

Irrigation Scheduling

  • Decision making process.
  • To determine when to irrigate the crops.
  • More useful in water scarce regions.
  • How much water to apply.
  • To supply plants with sufficient water.
  • Minimizing loss to deep percolation or runoff.
  • Key to improving performance and sustainability of the irrigation systems.
  • Requires good knowledge of the crops՚:
    • Water requirements
    • Soil water characteristics
    • How much water to apply
  • Appropriate irrigation scheduling ensures:
    • Water-logging is avoided.
    • Less water is used (saving water and energy) .
    • Creating optimum soil water conditions for plant growth.
  • Timing and depth criteria for irrigation scheduling:
    • Using several approaches on soil water measurements.
    • Soil water balance.
    • Plant stress indicators
    • Climatic parameters
    • Simple rules or very sophisticated models.

Methods of Irrigation

  • Selection of the right method of irrigation.
  • Influenced by soil type, land topography, crops to be grown, quality and quantity of water available.

Check Basin and Border Strip Irrigation

  • Surface irrigation.
  • Application of water by gravity.
  • Flow to the surface of the field.
  • Check basin is the easiest and least costly method.
  • Usually highly inefficient only less than 20 % of the water is taken up by the plant.
  • Most widely used method among Indian farmers.

Furrow Irrigation

  • Generally used to irrigate row crops and vegetables.
  • Suited to soils with infiltration rates between 0.5 and 2.5 % and a stream size of 1 - 2 litre.
  • Ideal for slopes varying from 0.2 to 0.5 % and a stream of size 1 - 2 litre/second.
  • Raised bed system and 20 - 30 % savings in irrigation water can be achieved by switching over to raise bed furrow irrigation systems.

Surge Flow Irrigation

  • Intermittent application of water.
  • A series of on and off modes of constant or variable time.
  • Spans has the potential of reducing intake and percolation losses.
  • Increasing the irrigation efficiencies and conserving irrigation water.
  • Major limitations for irrigation:
    • Excessive water intake
    • Deep percolation losses

Micro-Irrigation

  • One of the most efficient methods of irrigation.
  • Increased crop productivity and Enhanced water use.
  • A subsidy component by both the central and the state governments.
  • Area under micro-irrigation is about 8.7 % MH as on 2017.
  • Only 13 % of the potential area.
  • States accounting for 85 % of the total drip-irrigated area:
    • Maharashtra
    • Andhra Pradesh
    • Telangana
    • Karnataka
    • Gujarat
  • Rajasthan and Haryana top the list in case of sprinkler system.
  • This irrigation helps in attaining greater water-use efficiency.
  • Reduces the pressure on ground water resources with reduced GHG emissions.
  • Potential to function both as demand and supply side management tool.
  • It mainly includes drip irrigation and sprinkler system water application.

Prime Minister՚s Krishi Sinchayee Yojana (PMKsY)

  • Centrally sponsored scheme was enhanced in scope and renamed as National Mission on Micro Irrigation (NMMI) in 2010.
  • In 2015 NMKI was brought under the ambit of National Mission on Sustainable Agriculture.
  • PMKSY envisages providing end to end solution to irrigation supply chain.

Drip-Irrigation

  • Many advantages over the gravity surface irrigation methods.
  • In terms of water savings and yields.
  • Water use efficiency increases up to 100 % in a properly designed and managed drip irrigation system.
  • Helps to reduce the over-exploitation of groundwater that partly occurs because of inefficient use of water under surface method of irrigation.
  • Drip and micro-sprinkler irrigation systems:
    • Apply water slowly
    • On or below the water surface
    • As discrete or continuous drips
  • Further helps in achieving:
    • Early maturity of crops.
    • High quality produce.
    • Increased crop yields.
    • Higher-fertilizer use efficiency.
    • Reduction in weed growth.
    • Less labour requirement.
    • Less electric power consumption.
    • Cost of cultivation in inputs like fertilizers, labour, tilling and weeding.

Sprinkler Irrigation

  • Imitate natural rainfall.
  • Water is pumped through pipes and then sprayed onto the crops through rotating sprinkler heads.
  • More efficient than surface irrigation.
  • More costly to install.
  • Operate because of the need for pressurized water.
  • LEPA Or Low Energy Precision Application:
    • Offers a more efficient alternative.
    • Water is delivered to the crops from drop tubes.
    • Extending from sprinkler՚s arm.
    • Can achieve efficiencies as high as 95 % .
    • Saves as much as 20 to 50 % in energy costs compared with conventional systems.

Fertigation

  • Application of fertilizers through irrigation system.
  • A common practice in modern irrigated agriculture.
  • Localized irrigation systems involving highly high efficiency for water application are suitable.
  • Possible disadvantages:
    • Non-uniform chemical distribution.
    • With irrigation design or operation are inadequate.
    • The over fertilization (irrigation is not based on actual crop requirements)
    • Excessive use of soluble fertilizers.

Subsurface Drip Irrigation

  • A low pressure low volume irrigation system.
  • Uses buried tubes to apply water.
  • Through soil matrix suction the applied water moves out of the tubes.
  • Wetting occurs around the tubes.
  • Water moves out in the soil in all directions.
  • Potential disadvantages:
    • Water conservation
    • Enhanced fertilizer efficiency
    • Uniform and highly efficient water application
    • Elimination of surface infiltration problems
    • Evaporation losses.
    • Flexibility in providing frequent and light irrigations.
    • Reduced problems of disease and weeds.
    • Lower pressure required for operation.

Deficit Irrigation Practices

  • In arid and semi-arid regions.
  • Water availability is usually limited.
  • Not enough to achieve total crop water requirement and the maximum yields.
  • Irrigation is withheld at non-sensitive growth stages known as deficit irrigation.

Regulated Deficit Irrigation

  • An optimizing strategy.
  • Crops are allowed to sustain some degree of water deficit and yield reduction.
  • Crops is exposed to certain level of water stress.
  • During a particular period or throughout the growing season.
  • Main objective is to increase Water Use Efficiency (WUE) of the crop.
  • Improves fruit and quality.
  • Provides for leaching requirements to cope with salinity.
  • Optimization approach leads to economic viability.

Partial Root Drying

  • A new irrigation technique.
  • First applied to grapevines.
  • Subjected to one half of the root system to dry or drying conditions
  • Another half is irrigated.
  • Wetted and dried sides of the root system alternate to 7 - 14 days cycle.
  • Uses biochemical responses of plants to water stress.
  • To achieve balance between vegetative and reproductive growth.

Agronomic Practices

  • Soil management fertilizer application.
  • Disease and pest control
  • Related to sustainable water management.
  • In agriculture and protection of the environment.
  • Vital for increasing crop productivity and Water Use Efficiency (WUE) .
  • Traditional and modern soil and crop management practices of water conservation:
    • Runoff control
    • Improvement of soil infiltration rate
    • Increase soil water capacity
    • Control of soil water evaporation
    • Erosion control in agriculture

Contour Tillage

  • Soil cultivation is made along the land slope.
  • Soil is left with small furrows.
  • Ridges preventing runoff.
  • Effectively controls erosion.
  • May be applied to row crops and small grains
  • Provided the filed slopes are low.
  • Increased use of rain water especially in rainfed areas.

Broad Bed Planting

  • Cultivation of crops on broad beds.
  • Irrigation is applied in furrows.
  • Helps to save 30 - 40 % water.
  • Typically suitable for close planted filed crops and horticultural row crops.

Conservation Tillage (CT)

  • Includes zero tillage.
  • Retention of crop residuals on the soil surface at planting.
  • Crop residues act as mulches.
  • Reduced evaporation losses.
  • Protects the soil from the direct impact of raindrops.
  • Controls crusting and sealing processes.
  • Helps to maintain high levels of organic matter in the soil.
  • Highly effective improving soil infiltration.
  • Controls erosion resulting in increase of Water Use Efficiency (WUE) .

Mulch

  • Mulching with crop residues.
  • On soil surface shades the soil.
  • Slows water overland flow.
  • Improves infiltration conditions.
  • Reduces evaporation losses.
  • Control of weeds.
  • Non-beneficial water use.

Addition of Organic Manures

  • Increasing and maintaining the amount of organic matter.
  • Better soil aggregation in the upper soil layers.
  • Reduced crusting and sealing on soil surface.
  • Increased water retention capacity of the soil.

Addition of Clay or Hydrophilic Compound

  • Increases the water retention capacity of the soil.
  • Controls deep percolation.
  • Water availability in soils with low water holding capacity is increased.

Control of Acidity

  • Lime application to soils.
  • High pH favours more intensive and deep rooting.
  • Better crop development.
  • Contributes to improved soil aggregation.
  • Some increase in soil water availability.

Weed Control Measure

  • Adoption of appropriate weed control techniques.
  • To alleviate competition for water and transpiration losses by weeds.
  • Increases water use efficiency in different crops and cropping systems.

Integrated Pests Management (IPM)

  • To increase crop productivity.
  • Same amount of other inputs like water, fertilizers etc.
  • Timely control of severe pests and diseases increases the productivity and profitability to the farmers.
  • Improves water use efficiency along with water productivity.

- Published/Last Modified on: September 3, 2020

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