Water Productivity in AgricultureWater Productivity in Agriculture

Sharad K. Jain and Pushpendra K. Singh

ScientistsScientistsWater Resources Systems Division,

National Institute of Hydrology Roorkee, Uttarakhand 247667

WATER and LAND: The prime natural drivers

The most essential components of natural resourcessystem: availability and accessibility have played a key rolein determining the locations of cities, towns, and villagesaround the world.

The world will face a 40% water gap for covering the globaldrinking water, energy and food needs by 2030. Land andwater scarcity will play a major constraint for ensuring foodwater scarcity will play a major constraint for ensuring foodsecurity for ever-growing population.

land use land cover change; Urbanization and

industrialization ; engineering schemes likeg g

reservoirs, irrigation; inter‐basin transfers (that

maximize human access toF(X)

water) transform thenatural water systems to agreat extent; andgreat extent; and

Hydropower generation

U i d N i  ( )  United Nations (2001): 

transition from a rural, agrarian society to an urbanand industrial one and by 2050

abo t 70% of the global pop lation ill inhabit rban about 70% of the global population will inhabit urbanareas, up from about half today

Almost all of this increase in urbanpopulation will occur in the developing worldpopulation will occur in the developing worldand more than half of the growth will occur injust two countries, India and China (Cohen,2004)2004).

Inter Governmental Panel on Climate Change (IPCC AR5Inter‐Governmental Panel on Climate Change (IPCC‐AR5,2014) says:

1. between 1906‐2005: earth temperature has increased by 0.740Cdue to increase in anthropogenic emissions of greenhousegases;

2. by the end of this century the temperature increase is likely tobe 1.8‐4.00C.

This would lead to more frequent hot extremes, floods,droughts, cyclones and gradual recession of glaciers, whichin turn would result in greater instability in food production.

P l (2013)For each degree of global mean temperature rise,an additional 4% of the global land area is projectedPortmann et al. (2013): an additional 4% of the global land area is projectedto suffer a groundwater resources decrease of morethan 30%,

Gosling and Arnell (2016): applied 21 GCMs to 1339watersheds across the globe (under four SRES scenarios)

t l l t t i das a measure to calculate exposure to increases anddecreases in global water scarcity due to climate changeusing:

Water Crowding Index (WCI)Water Stress Index (WSI)Water Stress Index (WSI)

Results show that:• 1 6 (WCI) and 2 4 (WSI) billion people are currently• 1.6 (WCI) and 2.4 (WSI) billion people are currently

living within watersheds exposed to water scarcity.• Under A1B scenario, by 2050 nearly 0.5 to 3.1 billion

people will be exposed to an increase in water scarcitydue to climate change.

ON GLOBAL SCALE

the irrigated area has expanded to over 270 Mha, which 

ON GLOBAL SCALE

is about 18 % of total cultivated land;

an estimated 50 % of agricultural water withdrawals  an estimated 50 % of agricultural water withdrawals reach the crops – the remainder is lost in irrigation infrastructures (e.g., leaking and/or evaporating from i i ti   l   d  i )irrigation canals and pipes).

Agricultural sector is the largest consumer of water and consumes about 75 % of the water withdrawals; 20% of the water withdrawn is consumed by industrial activities and 5 % by domestic sector.activities and 5 % by domestic sector.

Competing water uses for main income groups ofp g g pcountries

According to United Nations population projections: Further the irrigated agriculture will have to be

Source: UNWWDR, 2003

According to United Nations population projections: Further, the irrigated agriculture will have to beconsiderably extended in the future in order to feed growing populations (an additional 1.5–2 billionpeople by 2025,

Water Availability and Sectorial Demands: IndianScenario

India receives annual precipitation of about 4000 BCM,including snowfall, out of which almost 75 % is receivedincluding snowfall, out of which almost 75 % is receivedduring the monsoon season.

The total average annual flow per year for the Indiang p yrivers is about 1869 BCM .

The annual utilizable surface water and groundwaterresources of India are 690 BCM and 431 BCM,respectively.

AgricultureAgriculture an important sector of our socio‐economic system; contributes approximately 14% of the nation’s gross

domestic product (GDP).; has the second largest arable land base (159.7 million

hectares) after USA and largest gross irrigated area (88) g g g (million hectares) in the world (India Water Portal:www.indiawaterportal.org);

Agriculture sector is the largest consumer of water Agriculture sector is the largest consumer of water .

Jain (2011) estimated:

Annual irrigation water requirement:

826 7 and 852 9 BCM respectively for 2050 and 2065 826.7 and 852.9 BCM, respectively for 2050 and 2065 approximately 40 % has to be fulfilled through

groundwater.

P l ti d U b i tiPopulation and UrbanizationMain components of the infrastructure sector which will befacing increasing stress on account of growing populationbecause the demand for water for various uses largelydepends on the population;

J i  ( )  i d

increased population will require domestic water supplies

Jain (2011) estimated:

increased population will require domestic water suppliesto the tune of 66.90, 118.58 and 122.59 BCM, respectivelyfor year 2025, 2050 and 2065;

the rural demands alone will require approximately89.67% of total domestic supplies by 2065.;

By 2065 a total of 567 million tonnes of food will requireto feed the total population of 1718 million.

Sl. No. Particulars UnitYear 2010* Year 2050* Revised estimates

Low  High Low  High2050 2065

Future water requirement (BCM) for irrigation (Jain, 2011)

demand demand demand demand2050 2065

1 Foodgrain demand Million tonnes 245.0 247.0 420.0 494.0 529.0 567.02 Net cultivable area Million hectares 143.0 143.0 145.0 145.0 145.0 145.03 Cropping intensity Percentage 135.0 135.0 150.0 160.0 158.0 163.04 Percentage of irrigated to gross cropped area Percentage 40 0 41 0 52 0 63 0 65 0 65 04 Percentage of irrigated to gross cropped area Percentage 40.0 41.0 52.0 63.0 65.0 65.05 Total cropped area Million  hectares 193.1 193.1 217.5 232.0 229.1 236 4

6 Total irrigated cropped area Million hectares 77.2 79.2 113.1 146.2 148.9 153.67 Total un‐irrigated cropped area Million hectares 115.8 113.9 104.4 85.8 80.2 82.78 Foodcrop area as percentage of irrigated area Percentage 70.0 70.0 70.0 70.0 70.0 70 09 Foodcrop area as percentage of un‐irrigated area Percentage 66.0 66.0 66.0 66.0 66.0 66.0

10 Foodcrop area – irrigated Million hectares 54.1 55.4 79.2 102.3 104.2 107.511 Foodcrop area – un‐irrigated Million hectares 76.4 75.2 68.9 56.7 52.9 54.612 Average yield ‐ irrigated food crop Tonnes/hectare 3.0 3.0 4.0 4.0 4.25 4.4013 Average yield – un‐irrigated food crop Tonnes/hectare 1 1 1 1 1 5 1 5 1 60 1 7013 Average yield un irrigated food crop Tonnes/hectare 1.1 1.1 1.5 1.5 1.60 1.7014 Foodgrain production from irrigated area Million tonnes 162.2 166.2 316.7 409.2 443.0 473.215 Foodgrain production from un‐irrigated area Million tonnes 84.1 82.7 103.4 85.0 84.7 92. 816 Total surrogate food production Million tonnes 246.3 248.9 420.0 494.2 527.7 566.017 Assumed percentage of potential from

f l i i i i lPercentage 47.0 47.0 54.3 54.3 54.3 54.3

surface water to total irrigation potential

18 Irrigated area from surface water Million hectares 36.3 37.2 61.4 79.4 80.9 83.419 Irrigated area from ground water Million hectares 40.9 41.9 51.7 66.6 68.1 70.220 Assumed 'Delta' for surface water Meter 0.91 0.91 0.61 0.61 0.61 0.6121 Assumed 'Delta' for ground water Meter 0.52 0.52 0.49 0.40 0.49 0. 4922 Surface water required for irrigation BCM 330.3 338.5 374.6 484.1 493.3 508.923 Ground water required for irrigation BCM 212.8 210.1 253.3 327.3 333.5 344.024 Total water required for irrigation BCM 543.1 556.7 627.9 811.4 826.7 852.9

Domestic water requirement in India for the years 2025, 2050 and 2065

Item Unit Year 2025 Year 2050 Year 2065

Population Million 1333 1692 1719p

Percentage urban ‐‐ 0.45 0.60 0. 65

Percentage rural ‐‐ 0.55 0.40 0. 35Percentage rural 55 4 35

Norm ‐ urbanarea

Ipcd 220 220 220

Norm ‐ rural area Ipcd 70 150 150

Demand ‐ urban BCM 48.17 81.52 89.67

Demand ‐ rural BCM 18.73 37. 05 32.92

T t l BCM 66 90 118 58 122 59Total BCM 66.90 118.58 122.59

Water‐Food‐Energy NexusWater Food Energy Nexus

f h d f d d d l d

http://www.futurewater.nl/

a far‐reaching vision oriented transformation is needed. Water and landconstraints, as well as the impacts of inter‐sectoral demands have to beconsidered in the development of water, energy and food solutions.

Water  availability for Irrigation? accounts for about 72% of global and 90% of developing‐country water accounts for about 72% of global and 90% of developing country water

withdrawals and thus leading to increased pressure on freshwaterresource;

further reduced due to rapidly increasing non‐agricultural water uses inindustry and households, as well as for environmental purposes.;

with the growing irrigation‐water demands and increasing competitionacross water‐using sectors.

This incites to exploreh fthe concept of waterproductivity (WP) inagriculture.g

Evaluating Water Resource UtilizationEvaluating Water Resource Utilization

Irrigation efficiency 

(Jensen, 2007) 

W     ffi i  

WATER RESOURCES 

Water use efficiency 

(Dong et al., 2011)

RESOURCES UTILIZATION Water productivity 

(Molden, 1997; Molden et al., 2010; Kijne et al., 2003)Kijne et al., 2003)

Virtual water content and water footprint (Elena and Esther, 2016; 

Zhang and Yang, 2014);

Irrigation Efficiency (Ei)

I h i f i i i d li d hIt represents the portion of irrigation water delivered to thetarget area that has been evaporated, or consumed, expressedas (Jensen, 2007):( )

PWETE i

i PWgi

where ET (Evapo transpiration) is the component of irrigationwhere, ETi (Evapo-transpiration) is the component of irrigationwater delivered that was consumed by (E = evaporation fromthe soil and plant surfaces and T = transpiration), Wg is thegross supply and Pe is the effective precipitation

Irrigation trade‐offs in Agriculture 

should be exploredfor variousdimensions of theoften-neglectedoften neglectedtradeoffs betweenirrigation efficiency( ith d ti it(with productivityenhancements) andwater for ecosystemprocesses ?

Irrigation trade-offs in agriculture (Scott et al., 2014)

Water use efficiency (WUE)Water use efficiency (WUE) Ratio of photosynthetic gross carbon assimilation (GPP) to

evapo‐transpiration (ET); acts as a critical link between carbon and water cycling in

terrestrial ecosystems.

Mathematically it can be expressed as (Dong et al 2011):

TxGPPGPPWUE

Mathematically, it can be expressed as (Dong et al., 2011):

ETx

TETWUE

where T is the vegetation transpiration GPP/T is the transpiration‐basedwhere T is the vegetation transpiration. GPP/T is the transpiration basedWUE, indicating the efficiency of plants in using water to produce drymatter;while T/ET, the ratio of transpiration to evapo‐transpiration, reflects how/ , p p p ,ecosystem water vapor flux is allocated between physical and biologicalprocesses. GPP/T and T/ET are affected by different processes.

Water Productivity (WP) Water Productivity (WP) 

Molden (1997): WP concept was originally promoted tot f th t f t b t di thaccount for the outcomes of water use by extending the

notion of Crop WUE (crop yield per unit seasonal evapo-transpiration).

Kijne et al. (2003): presented a collection of papers thatdiscussed definitions, applications and case studies of WP.discussed definitions, applications and case studies of WP.

Rodrigues and Pereira (2009): Increasing WP can beconsidered as the best a to achie e efficient ater se;considered as the best way to achieve efficient water use;

Numerous studies, both conceptuald l h b bl h dand practical, have been published

worldwide.

PRODUCTIVITY

is a measure of performance expressed as the ratio oft t t i t

PRODUCTIVITY

output to input.Productivity may be assessed for the whole system orparts of it.

total productivity – the ratio of total tangibleoutputs divided by total tangible inputs; and

partial or single factor productivity – the ratio oftotal tangible output to input of one factor withina systema system.

In farming systems the factors could be water, land, capital, labor and nutrients

Water productivity (WP): like land productivity, istherefore a partial‐factor productivity that measuresp p yhow the systems convert water into goods and services.

InputWater Water Usefrom DerivedOutput WP

WP i d d l i i WP was introduced to complement existing measures of the performance of irrigation systems, mainly the classic irrigation and effective efficiency (Keller et g y

al., 1996).

Cai and Rosegrant (2003) defined WP as: Crop yield per cubic meter of water consumption(WC)*, including ‘green’ water (effective rainfall) for(WC) , including green water (effective rainfall) forrain‐fed areas and both ‘green’ water and ‘blue’ water(diverted water fromwater systems) for irrigated areas.

)m(WC)kg(P)m/kg(WP

3

3 )m(WC

*WC i l d b fi i l t ti (BWC) d b fi i l t ti*WC includes beneficial water consumption (BWC) and non-beneficial water consumption(NBWC). BWC directly contributes to crop growth at the river-basin scale, and NBWCincludes distribution and conveyance losses to evaporation and sinks, which are noteconomically reusable.y

**BWC is characterized by water-use efficiency (WUE) in agriculture.

Physical Economical Nutritional

mass of agricultural output to the amount of water

d

monetary value derived per unit of water consumed

nutritional content pervolume of water

d ( l dconsumed consumed (Renault andWallender, 2000)

a concept highlighted by the Stockholm International Waterp g g yInstitute (SIWI) and the International Water ManagementInstitute (IWMI) under the idea of “more nutrition per drop

WP depends upon many factorsY  Crop patterns

WP depends upon many factors……………TIVIT

Y Crop patterns

Irrigation technology and field

DUCT

Cli t tt

water management

R PR

OD Climate patterns

land and infrastructure

WAT

ER  land and infrastructure

Other inputs, including labor,

WA p , g ,

fertilizer and machinery.

WP and Irrigation Water Management (IWM)WP and Irrigation Water Management (IWM)

Kang et al (2016); Oktem et al (2003) and Sharma et al (1990) studied the influence of Kang et al. (2016); Oktem et al. (2003), and Sharma et al. (1990) studied the influence ofirrigation on WP;

Zwart et al (2004) found that without irrigation WP in rainfed systems is low but WP Zwart et al. (2004) found that without irrigation WP in rainfed systems is low, but WPrapidly increases when a little irrigation water is applied;

Relationship between amounts of irrigation water applied (I) and measured crop water productivity (CWP) per unit water depletion for (a) wheat and (b)maize. (Zwart et al., 2004).

Notably a maximum WP will often not coincide with farmers’ interests whose aimNotably, a maximum WP will often not coincide with farmers interests, whose aimis maximum land productivity or economic profitability as shown in Figure 4. Itrequires a shift in irrigation science, irrigation water management and basin

ll f ‘ ld’water allocation to move away from ‘maximum irrigation-maximum yield’strategies to ‘less irrigation-maximum WP’ policies

Overall………

All types of water uses: Blue, Green, 

Gray Wide variety of outputs: Ph i l

Hydro‐Physical, 

Economical and 

Nutritional

yclimatic 

conditions

Agricultural WP Measures of 

technical and allocative 

Multiple sources of 

t efficiency

Multiple use and sequential 

Non‐water factors that 

water

qre‐use as the water cascades through the 

basin

affect productivity: Land, Crop, 

fertilisers, etc.

Water Productivity: a holistic and integrated performance assessment indicator of agricultural production system

Drivers of Change in Water Productivity

WP concept jointly represents the impact of engineering agronomicalWP concept jointly represents the impact of engineering agronomicalWP concept jointly represents the impact of engineering, agronomical,ecological and economical determinants which could help improveagricultural productivity with minimum stress to its determinants

WP concept jointly represents the impact of engineering, agronomical,ecological and economical determinants which could help improveagricultural productivity with minimum stress to its determinants

Actual Evapo‐transpiration (ETact)/Crop waterti (CWC) It i f th i t t f t iconsumption (CWC): It is one of the important factors governing

the WP for a particular crop and soil type;

A i l i C di ifi i C d i d Agronomical practices: Crop diversification, Crop production andBiomass: Efforts have to be evolved for crop diversification, less waterrequiring crops with improved agricultural productivity;

Engineering practices: Irrigation systems reliabilityand scheduling: In the arena of climate change and exceeding inter-sectoral demands, advanced irrigation engineering techniques (with improvedreliability and resilience), on-farm irrigation scheduling, water harvesting andmanagement practices will have to be introduced.

Soil moisture: Soil moisture budgeting process quantification. Engineeringas well as agronomical techniques shall have to be evolved to improve soilmoisture and quantify various processes to help improve WPmoisture and quantify various processes to help improve WP.

Geo‐hydrology: To help improve groundwater contribution to enhance WP,the geo-hydrological aspects such as occurrence and movement of groundwaterthe geo hydrological aspects such as occurrence and movement of groundwaterand its interaction with the environment shall have to be quantified at basin scale.

Water Footprint and Virtual Water: The concept of WF and VW canbe effectively incorporated to increase the WP Improved irrigation techniques withbe effectively incorporated to increase the WP. Improved irrigation techniques withemphasis on “More Crop per Drop” can help improve WP and reduce WF and VW inagricultural production;

Climate change: Mainly impacts the hydrologic cycle and water availabilitypatterns of a region. Hence appropriate mitigation technologies (engineering as wellas agronomical) shall have to be applied;

Economic and Policy Issues: Water pricing, Water audit andgovernment policy issues could have an everlasting effect on WP. These issues willhelp improve efficiency at basin and farm scale.

Therefore,

The concept of Water Productivity (WP)The concept of Water Productivity (WP)

…………establishing a linkage between

(i) Engineering determinants;(ii) Agronomical; and(iii) Economical determinants(iii) Economical determinants

could be one of the most vital tools to tackle thepresent problems of water scarcity and foodsecurity in India……

Approaches in Assessing Water Productivity

Water balance approach is used to assess the WP of agriculturalproduction systems;

WP i l d d t d b d t th l t l l fi ld l lWP is scale dependent and can be assessed at the plant level, field level,farm level, system level and basin level.

The amount of water used in production (denominator in Eq 3) can beThe amount of water used in production (denominator in Eq. 3) can beestimated depending on system boundaries and details available as:

• Gross inflow, Net inflow, and available water into a given field or catchmentarea;

• Depleted water: is the amount of water removed from the system by bothbeneficial and non-beneficial depletion.

• Beneficially depleted water, which is the amount of water depleted throughprocess and non-process beneficial use; andp p

• Process depleted water, which is the amount of water depleted throughprocess beneficial use.

Ways to Increase Water Productivity in Agriculture Ways to Increase Water Productivity in Agriculture (Technological, Management and Governance )

Increasing WP in agriculture means raising crop g g g pyields per unit of water consumed

In China, WP for non‐rice cereals ranges from 0.4 toIn China, WP for non rice cereals ranges from 0.4 to1.4 kg/m3;

In India WP for non rice cereal productivity rangesIn India, WP for non‐rice cereal productivity rangesfrom 0.2 to 0.7 kg/m3;

In the USA WP ranges from 0 9 to 1 9 kg/m3In the USA, WP ranges from 0.9 to 1.9 kg/m3.

Among Indian states, WP varies from 1.01 kg/m3 in Punjab (the highest) to30.21 kg/m3 in Orissa (the lowest) among states (Sharma et al., 2009).

Ways to increaseWP…………

Rao et al. (2016) found that deficit irrigation at 0.8 ETact could bed d f l l f d h h ld d dconsidered as useful tool for water saving and higher yield in arid and semi-

arid regions where irrigation water supplies are limited;

Patil et al. (2016) found that conservation agriculture (CA) can helpimprove WP;

Bar et al. (2015) found that indicated that irrigation scheduling hassignificant impact on WP;

Resource conservation technologies (RCTs): can help increase WP..

Framework for Increasing WP in AgricultureScale  Water balance Target Ways required

TECHNICAL WAYSPoint/plant 1.1 Transpiration efficiency Crop improvement

Access to inputs1.2 increased harvest index Crop science

Access to inputsAccess to inputsField/farmer Alter rainfall partitioning and 

Increase T/E ratioConservation agriculturePrecision FarmingClimate smart farmingSoil water conservation

Basin/system 3.1 Rainwater harvesting &     groundwater recharge

IWRM (Landuse planning)Watershed developmentAquifer mapping and zoning as per agroAquifer mapping and zoning as per agro‐ecological zones (AEZ)

3.2 Irrigation improvement: systems reliability and resilience

(a): On farm focus Drip/sprinkler irrigation(a): On‐farm focus Drip/sprinkler irrigationDeficit irrigationSupplemental irrigation

(b): System focus Improved supply delivery( ) y p pp y yWaste‐water re‐useDrainage re‐use

POLICY AND GOVERNANCEConsumers, private sectors  pay the environmental costs of food production andand city dwellers compensate to farming communities

Governments& Policy M k

provide economic incentives to produce more foodith l t t f l lMakers with less water at farm level;

fund for water resources development andmanagement;

fund for rural water infrastructures at farm and fund for rural water infrastructures at farm andbasin level

water use‐demand regulationsExtension and Awareness  farmers field schools;Extension and Awareness services 

farmers field schools; participatory water management programs; water users co‐operatives at sub‐basin and basin 

levellevelInstitutional: research and academic

enhanced water research endeavors in agriculture enhanced dissemination of research findings increase interaction between research and farmingincrease interaction between research and farming

communities.

Pradhan Mantri Krishi Sinchai YojanaPradhan Mantri Krishi Sinchai YojanaHar Hath Ko Kam, Har Khet Ko Pani

Rs. 50,000 crore over 2015‐2020 period with an additional Rs.20,000 crore placed at the disposal of NABARD

1 A l d I B f P (R 11 060 )1. Accelerated Irrigation Benefits Program (Rs. 11,060 crore);2. Micro-irrigation ('per drop, more crop’) (Rs. 16,300 crore);3. Watershed program (Rs. 13,590 crore) andp g ( )4. Har Khet Ko Pani (Rs. 9,050 crore) to construct one water harvesting

structure per village by 2020.

Water Productivity based prioritization and Zoning

Missing?Missing?

Water Productivity based prioritization and ZoningInstitutional: academic and research‐for performance assesment

i h f i f d d i i ill

Conclusions

1. WP is the net return for a unit of water used and increasing WP willhelp produce more food, income, better livelihoods and improvedecosystem services with less water.

2. Increasing WP will help maintain sufficient water in rivers, pondsand lakes and would lead to reduction in groundwater withdrawalsfor agriculture to sustain ecosystems and to meet the growingg y g gdemands of cities and industries.

3. More research endeavors are needed to enhance our understandingof WP in relation to dynamic hydro‐climatological, bio‐physical,socio‐economical systems for ensuring food security.

I li bl d ili t i i ti t ith i d4. Increase reliable and resilient irrigation systems with improved cropvarieties and application of conservation agriculture, precisionfarming and climate smart agricultural systems to in agriculture.

5. Various governance and policy steps should also be implemented toachieve the target of enhancing WP in agriculture for food security.

be cautious !

Crop water productivity is already quite high in highly productive regions, and gains in yield(per unit of land area) do not necessarily translate into gains in water productivity.

Reuse of water that takes place within an irrigated area or a basin can compensate for thep g pperceived losses at the field-scale in terms of water quantity, though the water quality islikely to be affected.

While crop breeding has played an important role in increasing water productivity in thep g p y p g p ypast, especially by improving the harvest index, such large gains are not easily foreseen inthe future.

More importantly, enabling conditions for farmers and water managers are not always in More importantly, enabling conditions for farmers and water managers are not always inplace to enhance water productivity.

Improving water productivity will thus require anunderstanding of the hydro‐climatological, bio‐physical, as well as the socio‐economicalenvironments crossing scales between field, farmand basin.

We can’t manufacture….

Water and LandJust..

Conserve and Manage

Thanks!