Water use productivity - Revision history

Avinash Kumar at 13:15, 16 August 2016

2016-08-16T13:15:47Z

Christoph Wagener at 13:05, 11 March 2014

2014-03-11T13:05:46Z

Christoph Wagener at 16:06, 6 March 2014

2014-03-06T16:06:22Z

Christoph Wagener at 16:05, 6 March 2014

2014-03-06T16:05:27Z

Christoph Wagener: Created page with " Water Use Productivity "

2014-03-06T15:16:34Z

Created page with " Water Use Productivity "

New page

Water Use Productivity

@@ Line 1: / Line 1: @@
-The “Water Productivity” (WP) term describes the ratio between the quantity of an (agricultural) product (biomass, yield) and the amount of water depleted or diverted. Until 2050, human population is projected to increase to 9 billion people and it is estimated that 70 per cent of additional food will have to be produced in order to [[Food_security|feed the humanity]] over the next 40 years. Meeting this challenge, the “Water Productivity term” plays a crucial role in modern agriculture which aims to increase yield production per hectare per unit of water used. Bearing in mind the consequences of climate change, an increase in water productivity helps to cope with predicted [[Impacts_of_climate_change_on_agricultural_water_management|water scarcity in agriculture]] and serves as an indicator for [[Sustainable_intensification|sustainable agricultural intensification]] (FAO 2012). Expert survey participants in the World Water Scenarios Project of the United Nations World Water Assessment Programme (WWAP) ranked increases in water productivity in agriculture as the most important development affecting water (WWAP 2012).
+The “Water Productivity” (WP) term describes the ratio between the quantity of an (agricultural) product (biomass, yield) and the amount of water depleted or diverted. Until 2050, human population is projected to increase to 9 billion people and it is estimated that 70 per cent of additional food will have to be produced in order to [[Food security|feed the humanity]] over the next 40 years. Meeting this challenge, the “Water Productivity term” plays a crucial role in modern agriculture which aims to increase yield production per hectare per unit of water used. Bearing in mind the consequences of climate change, an increase in water productivity helps to cope with predicted [[Impacts of climate change on agricultural water management|water scarcity in agriculture]] and serves as an indicator for [[Sustainable intensification|sustainable agricultural intensification]] (FAO 2012). Expert survey participants in the World Water Scenarios Project of the United Nations World Water Assessment Programme (WWAP) ranked increases in water productivity in agriculture as the most important development affecting water (WWAP 2012).
-= <span style="line-height: 1.5em; font-size: 0.85em;">More Crop per Drop</span> =
+= <span style="line-height: 1.5em;  font-size: 0.85em">More Crop per Drop</span> =
-The concept of WP developed from separate fields, for example crop physiologists defined [[Water_use_efficiency|water – use efficiency]] as carbon assimilated and crop yield per unit of transpiration or as the amount of biomass per unit of Evapotranspiration. The current understanding of water productivity developed including the benefits and costs of water used for agriculture.
+The concept of WP developed from separate fields, for example crop physiologists defined [[Water use efficiency|water – use efficiency]] as carbon assimilated and crop yield per unit of transpiration or as the amount of biomass per unit of Evapotranspiration. The current understanding of water productivity developed including the benefits and costs of water used for agriculture.
 == Definition ==
@@ Line 10: / Line 10: @@
 The concept of water productivity in agricultural production systems focuses on ‘''”producing more food with the same water resources''” or “''producing the same'amount of food with less water resources''”. Water productivity measures how a system converts water into goods and services, it is a measure of the beneficial output in relation to the water actually consumed, the ratio of the net benefits from crop, forestry, fishery, livestock and other mixed agricultural systems to the amount of water used in its production process. In a simple way, water productivity is defined as “''crop production” ''per unit ''“amount of water used'”''.
-The basic equation to calculate WP is: ''WP = Output derived from water use'''/ '''Water Input'' <span style="line-height: 1.5em; font-size: 0.85em;">The Water Input can be expressed by a set of choices according to the aim of the investigation. For example</span>
+The basic equation to calculate WP is: ''WP = Output derived from water use'''/ '''Water Input'' <span style="line-height: 1.5em;  font-size: 0.85em">The Water Input can be expressed by a set of choices according to the aim of the investigation. For example</span>
 *''Irrigation diversion''
 *''Gross/net inflow''
@@ Line 19: / Line 20: @@
 The Water output or the benefits can also be measured with various terms, for example with
 *''Economic value (monetary)''
 *''Physical mass (kilogram)''
@@ Line 28: / Line 30: @@
 <br/>
-*WP expressed in<u>kg''/''</u> might be of interest to an [[Design_for_irrigation|irrigation]] manager, while
 *<u>kg/m3 ET</u> (Evapotranspiration) could be a key issue for plant breeders and agronomic scientists.
-*WP in <u>US$''/''m3</u> of ET is more interesting to a [[Transboundary_water_management|basin development]] agency that is concerned with overall water consumption and the outputs generated.
+*WP in <u>US$''/''m3</u> of ET is more interesting to a [[Transboundary water management|basin development]] agency that is concerned with overall water consumption and the outputs generated.
 *A water resources planner might look at the difference between kg''/''m3 irrigation diversion and kg''/''m3 ET to assess how well irrigation water is managed.
-The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of [[Watershed_management|water management]] such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different [[Stakeholders_in_the_water_sector|stakeholders]] and researchers is provided.
+The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of [[Watershed management|water management]] such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different [[Stakeholders in the water sector|stakeholders]] and researchers is provided.
 <br/>
@@ Line 42: / Line 45: @@
 <br/>
 *increasing the marketable yield of the crops for each unit of water transpired
 *reducing the outflows and the atmospheric water depletion
-*enhancing the effective use of rainfall, of the water stored in the soil, and of the [[Irrigation_with_marginal_quality_water|marginal quality water]]
+*enhancing the effective use of rainfall, of the water stored in the soil, and of the [[Irrigation with marginal quality water|marginal quality water]]
 <br/>
@@ Line 51: / Line 55: @@
 <br/>
-*[[Anti-erosion_measures|soil]] and [[Water_harvesting|water conservation]] measures
-*applying water saving measures or [[Deficit_irrigation|improved irrigation techniques]]
+*[[Anti-erosion measures|soil]] and [[Water harvesting|water conservation]] measures
-*cultivation of less water demanding crops, or cultivation of crops adapted to [[Marginal_Water|marginal quality]]<br/>
+*applying water saving measures or [[Deficit irrigation|improved irrigation techniques]]
-*<span style="line-height: 1.5em; font-size: 0.85em;"></span>improvements in soil fertility<span style="line-height: 1.5em; font-size: 0.85em;"></span>
+*cultivation of less water demanding crops, or cultivation of crops adapted to [[Marginal Water|marginal quality]]<br/>
 *pest and disease control and many more…
 <br/>
-In smallholder livestock systems, feeding animals crop residues can provide a severalfold increase in water productivity. Higher water productivity can also be achieved through virtual water trade. By growing crops in places where climate enables high water productivity at lower cost and trading them to places with lower water productivity, [[Virtual_water_and_water_footprint|virtual water]] trade is already a reality for many water-scarce countries, and is expected to increase in the future (FAO 2012, Fader 2010).
+In smallholder livestock systems, feeding animals crop residues can provide a severalfold increase in water productivity. Higher water productivity can also be achieved through virtual water trade. By growing crops in places where climate enables high water productivity at lower cost and trading them to places with lower water productivity, [[Virtual water and water footprint|virtual water]] trade is already a reality for many water-scarce countries, and is expected to increase in the future (FAO 2012, Fader 2010).
 <br/>
@@ Line 65: / Line 70: @@
 == Concerns about the scope and ease of achieving water productivity gains ==
-Several publications show that there is considerable scope for improving crop water productivity through [[Rain_Water_Harvesting|water harvesting]], supplemental irrigation, [[Deficit_irrigation|deficit irrigation]], precision irrigation techniques, and soil-water conservation practices'''.'''
+Several publications show that there is considerable scope for improving crop water productivity through [[Rainwater harvesting|water harvesting]], supplemental irrigation, [[Deficit irrigation|deficit irrigation]], precision irrigation techniques, and soil-water conservation practices'''.'''
 But according to Molden (2010) and de Fraiture (2009), the scope and ease of achieving physical water productivity gains should not be assumed unfounded. They state that in most agricultural productive regions the WP is already quite high and perceived losses and inefficiencies might be lower than generally assumed. The re-use and recycling of water may be high too, and large gains through improvements in crop genetics are not foreseen in future. In other words, the enabling conditions for farmers and water managers are not in place to enhance water productivity. Some priority areas are defined where essential increases in WP are possible. These include areas where
 *poverty is high and water productivity is low
 *areas of physical water scarcity where competition for water is high
@@ Line 103: / Line 109: @@
 *Cai, X. et al. (2011): Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins. In: ''Water International'', 36:1, 42-62
 *Fader, M. (2010): Virtual water content of temperate cereals and maize: Present and potential future patterns. ''Journal of Hydrology'' 384, (3–4) 175-306
-*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organization of the United Nations, Rome, 2012<span style="line-height: 1.5em; font-size: 0.85em;"></span>
+*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organization of the United Nations, Rome, 2012<span style="line-height: 1.5em;  font-size: 0.85em"></span>
 *GIZ 2013: Agricultural Water Productivity as Adaptationto Climate Change (AWP-ACC)
 *Halsema, van G.E. and Vincent, L. (2012): Efficiency and productivity terms for water management: A matter of contextual relativism versus general absolutism. In: ''Agricultural Water Management'' 108 9– 15

@@ Line 1: / Line 1: @@
-The “Water Productivity” (WP) term describes the ratio between the quantity of an (agricultural) product (biomass, yield) and the amount of water depleted or diverted. Until 2050, human population is projected to increase to 9 billion people and it is estimated that 70 per cent of additional food will have to be produced in order to feed the humanity over the next 40 years. Meeting this challenge, the “Water Productivity term” plays a crucial role in modern agriculture which aims to increase yield production per hectare per unit of water used. Bearing in mind the consequences of climate change, an increase in water productivity helps to cope with predicted water scarcity in agriculture and serves as an indicator for sustainable agricultural intensification (FAO 2012). Expert survey participants in the World Water Scenarios Project of the United Nations World Water Assessment Programme (WWAP) ranked increases in water productivity in agriculture as the most important development affecting water (WWAP 2012).
+The “Water Productivity” (WP) term describes the ratio between the quantity of an (agricultural) product (biomass, yield) and the amount of water depleted or diverted. Until 2050, human population is projected to increase to 9 billion people and it is estimated that 70 per cent of additional food will have to be produced in order to [[Food_security|feed the humanity]] over the next 40 years. Meeting this challenge, the “Water Productivity term” plays a crucial role in modern agriculture which aims to increase yield production per hectare per unit of water used. Bearing in mind the consequences of climate change, an increase in water productivity helps to cope with predicted [[Impacts_of_climate_change_on_agricultural_water_management|water scarcity in agriculture]] and serves as an indicator for [[Sustainable_intensification|sustainable agricultural intensification]] (FAO 2012). Expert survey participants in the World Water Scenarios Project of the United Nations World Water Assessment Programme (WWAP) ranked increases in water productivity in agriculture as the most important development affecting water (WWAP 2012).
 = <span style="line-height: 1.5em; font-size: 0.85em;">More Crop per Drop</span> =
-The concept of WP developed from separate fields, for example crop physiologists defined water – use efficiency as carbon assimilated and crop yield per unit of transpiration or as the amount of biomass per unit of Evapotranspiration. The current understanding of water productivity developed including the benefits and costs of water used for agriculture.
+The concept of WP developed from separate fields, for example crop physiologists defined [[Water_use_efficiency|water – use efficiency]] as carbon assimilated and crop yield per unit of transpiration or as the amount of biomass per unit of Evapotranspiration. The current understanding of water productivity developed including the benefits and costs of water used for agriculture.
 == Definition ==
@@ Line 28: / Line 28: @@
 <br/>
-*WP expressed in<u>kg''/''</u> might be of interest to an irrigation manager, while
+*WP expressed in<u>kg''/''</u> might be of interest to an [[Design_for_irrigation|irrigation]] manager, while
 *<u>kg/m3 ET</u> (Evapotranspiration) could be a key issue for plant breeders and agronomic scientists.
-*WP in <u>US$''/''m3</u> of ET is more interesting to a basin development agency that is concerned with overall water consumption and the outputs generated.
+*WP in <u>US$''/''m3</u> of ET is more interesting to a [[Transboundary_water_management|basin development]] agency that is concerned with overall water consumption and the outputs generated.
 *A water resources planner might look at the difference between kg''/''m3 irrigation diversion and kg''/''m3 ET to assess how well irrigation water is managed.
-The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of water management such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different stakeholders and researchers is provided.
+The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of [[Watershed_management|water management]] such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different [[Stakeholders_in_the_water_sector|stakeholders]] and researchers is provided.
 <br/>
@@ Line 44: / Line 44: @@
 *increasing the marketable yield of the crops for each unit of water transpired
 *reducing the outflows and the atmospheric water depletion
-*enhancing the effective use of rainfall, of the water stored in the soil, and of the marginal quality water
+*enhancing the effective use of rainfall, of the water stored in the soil, and of the [[Irrigation_with_marginal_quality_water|marginal quality water]]
 <br/>
@@ Line 51: / Line 51: @@
 <br/>
-*soil and water conservation measures
+*[[Anti-erosion_measures|soil]] and [[Water_harvesting|water conservation]] measures
-*applying water saving measures or improved irrigation techniques
+*applying water saving measures or [[Deficit_irrigation|improved irrigation techniques]]
-*cultivation of less water demanding crops, or cultivation of crops adapted to marginal quality<br/>
+*cultivation of less water demanding crops, or cultivation of crops adapted to [[Marginal_Water|marginal quality]]<br/>
 *<span style="line-height: 1.5em; font-size: 0.85em;"></span>improvements in soil fertility<span style="line-height: 1.5em; font-size: 0.85em;"></span>
 *pest and disease control and many more…
@@ Line 59: / Line 59: @@
 <br/>
-In smallholder livestock systems, feeding animals crop residues can provide a severalfold increase in water productivity. Higher water productivity can also be achieved through virtual water trade. By growing crops in places where climate enables high water productivity at lower cost and trading them to places with lower water productivity, virtual water trade is already a reality for many water-scarce countries, and is expected to increase in the future (FAO 2012, Fader 2010).
+In smallholder livestock systems, feeding animals crop residues can provide a severalfold increase in water productivity. Higher water productivity can also be achieved through virtual water trade. By growing crops in places where climate enables high water productivity at lower cost and trading them to places with lower water productivity, [[Virtual_water_and_water_footprint|virtual water]] trade is already a reality for many water-scarce countries, and is expected to increase in the future (FAO 2012, Fader 2010).
 <br/>
@@ Line 65: / Line 65: @@
 == Concerns about the scope and ease of achieving water productivity gains ==
-Several publications show that there is considerable scope for improving crop water productivity through water harvesting, supplemental irrigation, deficit irrigation, precision irrigation techniques, and soil-water conservation practices'''.'''
+Several publications show that there is considerable scope for improving crop water productivity through [[Rain_Water_Harvesting|water harvesting]], supplemental irrigation, [[Deficit_irrigation|deficit irrigation]], precision irrigation techniques, and soil-water conservation practices'''.'''
 But according to Molden (2010) and de Fraiture (2009), the scope and ease of achieving physical water productivity gains should not be assumed unfounded. They state that in most agricultural productive regions the WP is already quite high and perceived losses and inefficiencies might be lower than generally assumed. The re-use and recycling of water may be high too, and large gains through improvements in crop genetics are not foreseen in future. In other words, the enabling conditions for farmers and water managers are not in place to enhance water productivity. Some priority areas are defined where essential increases in WP are possible. These include areas where

@@ Line 8: / Line 8: @@
 == Definition ==
-The concept of water productivity in agricultural production systems focuses on ‘''”producing more food with the same water resources''” or “''producing the same''''amount of food with less water resources''”. Water productivity measures how a system converts water into goods and services, it is a measure of the beneficial output in relation to the water actually consumed, the ratio of the net benefits from crop, forestry, fishery, livestock and other mixed agricultural systems to the amount of water used in its production process. In a simple way, water productivity is defined as “''crop production” ''per unit ''“amount of water used''''”''.
+The concept of water productivity in agricultural production systems focuses on ‘''”producing more food with the same water resources''” or “''producing the same'amount of food with less water resources''”. Water productivity measures how a system converts water into goods and services, it is a measure of the beneficial output in relation to the water actually consumed, the ratio of the net benefits from crop, forestry, fishery, livestock and other mixed agricultural systems to the amount of water used in its production process. In a simple way, water productivity is defined as “''crop production” ''per unit ''“amount of water used'”''.
-The basic equation to calculate WP is: ''WP = Output derived from water use'''/ '''Water Input''
+The basic equation to calculate WP is: ''WP = Output derived from water use'''/ '''Water Input'' <span style="line-height: 1.5em; font-size: 0.85em;">The Water Input can be expressed by a set of choices according to the aim of the investigation. For example</span>
 <span style="line-height: 1.5em; font-size: 0.85em;">The Water Input can be expressed by a set of choices according to the aim of the investigation. For example</span>
 *''Irrigation diversion''
 *''Gross/net inflow''
@@ Line 17: / Line 16: @@
 *''Precipitation''
+<br/>
 The Water output or the benefits can also be measured with various terms, for example with
@@ Line 23: / Line 22: @@
 *''Physical mass (kilogram)''
 *''Nutritional value (calories)''
 <br/>
@@ Line 28: / Line 28: @@
 <br/>
 *WP expressed in<u>kg''/''</u> might be of interest to an irrigation manager, while
 *<u>kg/m3 ET</u> (Evapotranspiration) could be a key issue for plant breeders and agronomic scientists.
 *WP in <u>US$''/''m3</u> of ET is more interesting to a basin development agency that is concerned with overall water consumption and the outputs generated.
@@ Line 35: / Line 35: @@
 The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of water management such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different stakeholders and researchers is provided.
+<br/>
 == Potential Measures to achieve higher WP ==
 The objective of higher water use productivity can for example be pursued by
-−
 *increasing the marketable yield of the crops for each unit of water transpired
 *reducing the outflows and the atmospheric water depletion
 *enhancing the effective use of rainfall, of the water stored in the soil, and of the marginal quality water
+<br/>
 To achieve these goals, a wide range of measures may be adopted, for example
+<br/>
 *soil and water conservation measures
 *applying water saving measures or improved irrigation techniques
@@ Line 63: / Line 63: @@
 <br/>
-== Concerns about the scope and ease of achieving water productivity gains  ==
+== Concerns about the scope and ease of achieving water productivity gains ==
 Several publications show that there is considerable scope for improving crop water productivity through water harvesting, supplemental irrigation, deficit irrigation, precision irrigation techniques, and soil-water conservation practices'''.'''
 But according to Molden (2010) and de Fraiture (2009), the scope and ease of achieving physical water productivity gains should not be assumed unfounded. They state that in most agricultural productive regions the WP is already quite high and perceived losses and inefficiencies might be lower than generally assumed. The re-use and recycling of water may be high too, and large gains through improvements in crop genetics are not foreseen in future. In other words, the enabling conditions for farmers and water managers are not in place to enhance water productivity. Some priority areas are defined where essential increases in WP are possible. These include areas where
 *poverty is high and water productivity is low
 *areas of physical water scarcity where competition for water is high
@@ Line 73: / Line 73: @@
 *areas of water-driven ecosystem degradation (falling groundwater tables, river desiccation) (Molden et al. 2010)
+<br/>
 There is greater reason to be optimistic about increasing economic water productivity by switching to higher value agricultural uses and by reducing costs pf production.
@@ Line 83: / Line 83: @@
 Egypt’s climate can be categorized as hot arid desert climate with variable rainfall and recurrent droughts particularly in the northern Nile Delta. The natural resources, especially the limited water resources, are under great pressure. The Government of Egypt has responded to the pressing threat of climate change by forming an Climate Change Committee and developing various general and sector-specific strategies. The priority sectors water, agriculture, coastal zones, tourism, housing, roads, health were identified along with potential and priority mitigation and adaptation measures.
+<br/>
 '''Objective'''
 The Objective of the programme is to <u>improve Agricultural Water Productivity</u> as a means to adapt to climate change by optimizing fertilizer practices and pesticides, crop rotation and the planting calendar.
-−
 '''Impact'''
@@ Line 106: / Line 106: @@
 *GIZ 2013: Agricultural Water Productivity as Adaptationto Climate Change (AWP-ACC)
 *Halsema, van G.E. and Vincent, L. (2012): Efficiency and productivity terms for water management: A matter of contextual relativism versus general absolutism. In: ''Agricultural Water Management'' 108 9– 15
-*Molden, D., ''et al''., 2010. Improving agricultural water productivity: between optimism and caution. ''Agricultu''''ral Water Management'', 97 (4), 528–535.
+*Molden, D., ''et al''., 2010. Improving agricultural water productivity: between optimism and caution. ''Agricultural Water Management'', 97 (4), 528–535.
 *Pereiraa, L. S., Corderyb, I., Iacovidesc, I. (2012): Improved indicators of water use performance and productivity for sustainable water conservation and saving. In: ''Agricultural Water Management'' 108, 39– 51
 *Singh, R. 2005. ''Water productivity analysis from field to regional scale: integration of crop and soil modelling, remote sensing and geographical information''. Doctoral thesis, Wageningen University, Wageningen, The Netherlands.
 *WASAMED 2005: Water Use Efficiency and Water Productivity - Proceedings of 4th WASAMED (WAter SAving in MEDiterranean agriculture) Workshop. Amman (Jordan), 30 Sept. - 4 Oct. 2005. In: ''Options Méditerranéennes, Séries B n. 57''
 *WWAP (World Water Assessment Programme). 2012. ''The United Nations World Water Development Report 4: Managing Water under Uncertainty and Risk''. Paris, UNESCO

← Older revision		Revision as of 16:05, 6 March 2014
Line 1:		Line 1:

−	Water Use Productivity	+	The “Water Productivity” (WP) term describes the ratio between the quantity of an (agricultural) product (biomass, yield) and the amount of water depleted or diverted. Until 2050, human population is projected to increase to 9 billion people and it is estimated that 70 per cent of additional food will have to be produced in order to feed the humanity over the next 40 years. Meeting this challenge, the “Water Productivity term” plays a crucial role in modern agriculture which aims to increase yield production per hectare per unit of water used. Bearing in mind the consequences of climate change, an increase in water productivity helps to cope with predicted water scarcity in agriculture and serves as an indicator for sustainable agricultural intensification (FAO 2012). Expert survey participants in the World Water Scenarios Project of the United Nations World Water Assessment Programme (WWAP) ranked increases in water productivity in agriculture as the most important development affecting water (WWAP 2012).
		+
		+	= <span style="line-height: 1.5em; font-size: 0.85em;">More Crop per Drop</span> =
		+
		+	The concept of WP developed from separate fields, for example crop physiologists defined water – use efficiency as carbon assimilated and crop yield per unit of transpiration or as the amount of biomass per unit of Evapotranspiration. The current understanding of water productivity developed including the benefits and costs of water used for agriculture.
		+
		+	== Definition ==
		+
		+	The concept of water productivity in agricultural production systems focuses on ‘''”producing more food with the same water resources''” or “''producing the same''''amount of food with less water resources''”. Water productivity measures how a system converts water into goods and services, it is a measure of the beneficial output in relation to the water actually consumed, the ratio of the net benefits from crop, forestry, fishery, livestock and other mixed agricultural systems to the amount of water used in its production process. In a simple way, water productivity is defined as “''crop production” ''per unit ''“amount of water used''''”''.
		+
		+	The basic equation to calculate WP is: ''WP = Output derived from water use'''/ '''Water Input''
		+	<span style="line-height: 1.5em; font-size: 0.85em;">The Water Input can be expressed by a set of choices according to the aim of the investigation. For example</span>
		+	*''Irrigation diversion''
		+	*''Gross/net inflow''
		+	*''Evapotranspiration''
		+	*''Precipitation''
		+
		+
		+
		+	The Water output or the benefits can also be measured with various terms, for example with
		+	*''Economic value (monetary)''
		+	*''Physical mass (kilogram)''
		+	*''Nutritional value (calories)''
		+	<br/>
		+
		+	Therefore the calculated Indicator ''<u>“Water Productivity”</u>'' is expressed in different ways according to specific interests to examine water-use performances.
		+
		+	<br/>
		+	*WP expressed in<u>kg''/''</u> might be of interest to an irrigation manager, while
		+	*<u>kg/m3 ET</u> (Evapotranspiration) could be a key issue for plant breeders and agronomic scientists.
		+	*WP in <u>US$''/''m3</u> of ET is more interesting to a basin development agency that is concerned with overall water consumption and the outputs generated.
		+	*A water resources planner might look at the difference between kg''/''m3 irrigation diversion and kg''/''m3 ET to assess how well irrigation water is managed.
		+
		+	The <u>“water footprint”</u>''', '''the concept of water accounting by product, is also a way of expressing the WP of a given product or service, for example of the manufacturing industries (Cai et al. 2011, Singh 2005). Subsuming, the concept of water productivity describes various aspects of water management such as production, utilization and economy at different scales. These possible variations ensure the flexibility and robustness of the tool to measure efficiency of water use. Thus a conceptual framework for different stakeholders and researchers is provided.
		+
		+
		+
		+	== Potential Measures to achieve higher WP ==
		+
		+	The objective of higher water use productivity can for example be pursued by
		+
		+
		+	*increasing the marketable yield of the crops for each unit of water transpired
		+	*reducing the outflows and the atmospheric water depletion
		+	*enhancing the effective use of rainfall, of the water stored in the soil, and of the marginal quality water
		+
		+
		+
		+	To achieve these goals, a wide range of measures may be adopted, for example
		+
		+
		+	*soil and water conservation measures
		+	*applying water saving measures or improved irrigation techniques
		+	*cultivation of less water demanding crops, or cultivation of crops adapted to marginal quality<br/>
		+	*<span style="line-height: 1.5em; font-size: 0.85em;"></span>improvements in soil fertility<span style="line-height: 1.5em; font-size: 0.85em;"></span>
		+	*pest and disease control and many more…
		+
		+	<br/>
		+
		+	In smallholder livestock systems, feeding animals crop residues can provide a severalfold increase in water productivity. Higher water productivity can also be achieved through virtual water trade. By growing crops in places where climate enables high water productivity at lower cost and trading them to places with lower water productivity, virtual water trade is already a reality for many water-scarce countries, and is expected to increase in the future (FAO 2012, Fader 2010).
		+
		+	<br/>
		+
		+	== Concerns about the scope and ease of achieving water productivity gains ==
		+
		+	Several publications show that there is considerable scope for improving crop water productivity through water harvesting, supplemental irrigation, deficit irrigation, precision irrigation techniques, and soil-water conservation practices'''.'''
		+
		+	But according to Molden (2010) and de Fraiture (2009), the scope and ease of achieving physical water productivity gains should not be assumed unfounded. They state that in most agricultural productive regions the WP is already quite high and perceived losses and inefficiencies might be lower than generally assumed. The re-use and recycling of water may be high too, and large gains through improvements in crop genetics are not foreseen in future. In other words, the enabling conditions for farmers and water managers are not in place to enhance water productivity. Some priority areas are defined where essential increases in WP are possible. These include areas where
		+	*poverty is high and water productivity is low
		+	*areas of physical water scarcity where competition for water is high
		+	*areas with little water resources development
		+	*areas of water-driven ecosystem degradation (falling groundwater tables, river desiccation) (Molden et al. 2010)
		+
		+
		+
		+	There is greater reason to be optimistic about increasing economic water productivity by switching to higher value agricultural uses and by reducing costs pf production.
		+
		+	= GIZ Project Example - Agricultural Water Productivity as Adaptation to Climate Change (AWP-ACC) =
		+
		+	'''Context'''
		+
		+	Egypt’s climate can be categorized as hot arid desert climate with variable rainfall and recurrent droughts particularly in the northern Nile Delta. The natural resources, especially the limited water resources, are under great pressure. The Government of Egypt has responded to the pressing threat of climate change by forming an Climate Change Committee and developing various general and sector-specific strategies. The priority sectors water, agriculture, coastal zones, tourism, housing, roads, health were identified along with potential and priority mitigation and adaptation measures.
		+
		+
		+
		+	'''Objective'''
		+
		+	The Objective of the programme is to <u>improve Agricultural Water Productivity</u> as a means to adapt to climate change by optimizing fertilizer practices and pesticides, crop rotation and the planting calendar.
		+
		+
		+
		+	'''Impact'''
		+
		+	Adapted farming and <u>improved irrigation-methods</u> increase water productivity while protecting soil and water resources. Reuse of treated drainage and wastewater lead to a diversification of water resources, thus making farmers and other water users less vulnerable to unstable water supply. Ensuring and improving agricultural production provides food and income security.
		+
		+	Increased energy efficiency in water supply also increases water productivity while reducing the energy demand, thus contributing to both adaptation to and mitigation of climate change.
		+
		+	<br/>
		+
		+	= References and further information =
		+
		+	*Cai, X. et al. (2011): Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins. In: ''Water International'', 36:1, 42-62
		+	*Fader, M. (2010): Virtual water content of temperate cereals and maize: Present and potential future patterns. ''Journal of Hydrology'' 384, (3–4) 175-306
		+	*FAO (2012): Coping with water scarcity. An action framework for agriculture and food security. Food and Agriculture Organization of the United Nations, Rome, 2012<span style="line-height: 1.5em; font-size: 0.85em;"></span>
		+	*GIZ 2013: Agricultural Water Productivity as Adaptationto Climate Change (AWP-ACC)
		+	*Halsema, van G.E. and Vincent, L. (2012): Efficiency and productivity terms for water management: A matter of contextual relativism versus general absolutism. In: ''Agricultural Water Management'' 108 9– 15
		+	*Molden, D., ''et al''., 2010. Improving agricultural water productivity: between optimism and caution. ''Agricultu''''ral Water Management'', 97 (4), 528–535.
		+	*Pereiraa, L. S., Corderyb, I., Iacovidesc, I. (2012): Improved indicators of water use performance and productivity for sustainable water conservation and saving. In: ''Agricultural Water Management'' 108, 39– 51
		+	*Singh, R. 2005. ''Water productivity analysis from field to regional scale: integration of crop and soil modelling, remote sensing and geographical information''. Doctoral thesis, Wageningen University, Wageningen, The Netherlands.
		+	*WASAMED 2005: Water Use Efficiency and Water Productivity - Proceedings of 4th WASAMED (WAter SAving in MEDiterranean agriculture) Workshop. Amman (Jordan), 30 Sept. - 4 Oct. 2005. In: ''Options Méditerranéennes, Séries B n. 57''
		+	*WWAP (World Water Assessment Programme). 2012. ''The United Nations World Water Development Report 4: Managing Water under Uncertainty and Risk''. Paris, UNESCO