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More food, but less land and water for nature: unforeseen and substantial global increase in land and water usage

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Can the world succeed in becoming more efficient with water and food resources, while preserving sufficient nature by 2050? No, according to a recent study* (Seijger et al., 2024) that assessed the period after the Green Revolution, from 2000 to 2020, and concluded considerably more agricultural land was required than initially anticipated. This will result in significant depletion of water reserves and loss of natural land. Compared to envisioned scenarios for water and agriculture, the world is on a trajectory toward the direst conceivable outcome. Anticipated enhancements in international trade, rain-dependent farming, and irrigated agriculture have not been realized. Who bears the immediate consequences? Primarily, the environment, with diminished forests, dwindling rivers, and diminishing natural habitats. Moreover, the most impoverished suffer, as disappointing yields and reduced grain trade will contribute to escalating food costs and food insecurity.

The point of departure for this study was the publication 'Water for Food, Water for Life: Comprehensive Assessment of Water Management for Agriculture' (Molden, 2007). This influential work from 2007, akin to the IPCC climate reports as it involved over 700 scientists, demonstrated that producing sufficient food by 2050 without significantly increasing water consumption and agricultural land was feasible. This would entail optimizing international trade and the productivity of rain-dependent agriculture, along with limited expansion and improved productivity in irrigation.

To assess potential improvements, researchers from Wageningen University & Research collaborated with international water and agriculture organizations (IRRI, IWMI, IIASA, IHE Delft)*. They employed national agricultural data (collected by the FAO and available in FAOSTAT) to gauge global advancements.

The study shows that anticipated progress in international trade and rain-dependent farming has faltered. In the world's major cereal-producing regions (Europe, North America, Australia, South America, Central Asia, and Eastern Europe), there has been a decline in agricultural land, paradoxically in climates with adequate water for cereal production that could be used to feed other regions (sub-Saharan Africa, Middle East, Eastern Asia).

Furthermore, sub-Saharan Africa has not realised the envisaged increases in grain production per hectare, leading to a substantial expansion of agricultural land that directly encroaches upon natural ecosystems. Irrigation in Asia, Latin America, and the Middle East has escalated far more swiftly than anticipated in the publication, thereby contributing to expedited depletion of water reserves. Cereal yields increased slightly, by 1.38% per year during 2000-2020.

The trends spanning 2000-2020 thus illustrate that anticipated enhancements have fallen short. The world is headed towards the direst conceivable scenario, where water consumption and agricultural land will double by 2050 compared to 2000, directly jeopardizing land and water designated for nature.

This study therefore adds much-needed evidence to be cautious about the realistic, achievable gains in land and water productivity. Not only due to the limited progress in international trade and rainfed agriculture but also because other avenues did not contribute to realistic gains. Crops have not become more efficient in converting water into biomass as photosynthesis breakthroughs did not occur. In addition, variation in crop water productivity might be explained by methodological procedures (satellite data, agronomic studies) but do not represent true field-level variation in evapotranspiration and biomass.

As authors, we were surprised by how telling the evidence was that the most optimistic scenarios of the Comprehensive Assessment – improve rainfed production, optimise trade, modest expansion irrigation - did not materialise. During the Post-Green Revolution period of 2000 to 2020, the world has clearly not succeeded in veering off the development path of more land and water for agriculture at the expense of the environment. Climate change, poor drainage, soil salinity, unsustainable mining of groundwater, and demands for feed and biofuel crops all continue to affect this rather pessimistic development path.

The study therefore concludes that given the observed relatively small gains in land and water productivity, the world will fall short against its food, water security, and biodiversity targets. Significant systemic shifts in our agricultural food systems are needed to veer off this development path. The main options do not lie in further improving land and water productivity, but rather in changing agricultural and food systems with a multipronged approach to:

  • Gradually change, for large parts of the world, to a diet in which plant-based calory intake is prevalent to effectively reduce total agricultural land and water use.
  • Reduce industrial crops and food waste along the value chain from farm production to consumption to effectively reduce total agricultural land and water use.
  • Increase or stabilise productivity against a changing climate, associated shocks, and depleting water resources as crop yields level off and climate extremes increase.
  • Increase the use of underutilised traditional crop types as they are nutritious and often more resilient to climate change than high-yielding varieties.

The Comprehensive Assessment considered most of these options, but did not prioritise them in the 2050 scenarios. The last twenty years have made clear these are the few remaining options through which the world can feed itself while protecting nature.

This multipronged approach that we propose requires strong coordinated leadership and governance at a global level – something that was not witnessed for the period 2000 to 2020 - to divert the world from its unsustainable path of using steadily more land and water to produce food, feed, and biofuel at the expense of nature. Effective implementation in the coming decades, for instance by incentivising farmers in large parts of the world to produce food crops rather than biofuel or fodder, might just provide a turn-off from the current pessimistic path. The approach therefore represents a small opportunity to pursue the original, admirable mission of the Comprehensive Assessment in 2007 of producing sufficient food by 2050 without a significant escalation in water consumption and agricultural land.


*The paper was co-authored by Anton Urfels from IRRI, Simon Langan from IWMI, Maria Christoforidou, Petra Hellegers, Gerlo Borghuis and Gerardo van Halsema from Wageningen University. Earlier versions received valuable inputs from Charlotte de Fraiture from IHE Delft, anonymous reviewers were instrumental in scoping and nuancing the manuscript.

References

FAO, 2023. FAOSTAT Database, License: CC BY-NC-SA 3.0 IGO. FAO, Rome. https://www.fao.org/faostat/en/#data

Seijger, C.; Urfels, A.; Christoforidou, M.; Hellegers, P.; Borghuis, G.; Langan, S. and van Halsema, G. 2025. More food, but less land and water for nature: Why agricultural productivity gains did not materialize. Agricultural Water Management 307(2025), https://doi.org/10.1016/j.agwat.2024.109229

Molden, D. (Ed.), 2007. Water for Food Water for Life. A Comprehensive Assessment of Water Management in Agriculture. Earthscan, London and International Water Management Institute, Colombo. https://archive.iwmi.org/assessment/Publications/books.htm

Photo credit: Bruce Barnett/Flickr. Irrigating tomato fields, Davis CA, USA


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Comments 15

Guest
Guest - Pieter van der Zaag on Wednesday, 15 January 2025 14:39
Focus on Africa

This is a very useful and incisive piece with a sobering conclusion. Important to take account of our failure to live up to the high expectations raised by the comprehensive assessment, learn, and do something with it.

My perhaps naïve hope is still focused on Africa, where there is still scope for significantly improving agriculture, in terms of crop yields and resilience. But then there is need to explore under-utilised opportunities. This implies a shift away from the ill-fated (build, neglect and rehabilitate!) plantation-type and scheme type of solutions embraced by so many, in favour of farmer-led approaches that empower individual rural households. For this to succeed it must become much cheaper for smallholder farmers to invest, as current loan facilities are prohibitive, unaffordable, unreachable etc. for emergent rural entrepreneurs, male and female, stifling initiative and innovation.

African agriculture needs to become more resilient to a steadily increasing climate variability. Access to water storage is therefore needed, preferably nature-based storage as this is both cheap and ecologically sound. Here I make the case for using the nature-based water storage of sand rivers in the arid to semi-arid regions of Africa (see https://sandrivers.org/).

With my sand river friends we’ve set a target of promoting farmer-led irrigation along sand rivers in African drylands for 1 million households to reliably cultivate at least 0.2 million ha by 2030. This is possible, as there is no need for building expensive dams nor schemes. The only thing needed are small interest-free loans - indeed, one million loans of US$ 1,000 at most. And farmers will be able to pay it all back, within 3 years. It can be done. So let’s do it!

This is a very useful and incisive piece with a sobering conclusion. Important to take account of our failure to live up to the high expectations raised by the comprehensive assessment, learn, and do something with it. My perhaps naïve hope is still focused on Africa, where there is still scope for significantly improving agriculture, in terms of crop yields and resilience. But then there is need to explore under-utilised opportunities. This implies a shift away from the ill-fated (build, neglect and rehabilitate!) plantation-type and scheme type of solutions embraced by so many, in favour of farmer-led approaches that empower individual rural households. For this to succeed it must become much cheaper for smallholder farmers to invest, as current loan facilities are prohibitive, unaffordable, unreachable etc. for emergent rural entrepreneurs, male and female, stifling initiative and innovation. African agriculture needs to become more resilient to a steadily increasing climate variability. Access to water storage is therefore needed, preferably nature-based storage as this is both cheap and ecologically sound. Here I make the case for using the nature-based water storage of sand rivers in the arid to semi-arid regions of Africa (see https://sandrivers.org/). With my sand river friends we’ve set a target of promoting farmer-led irrigation along sand rivers in African drylands for 1 million households to reliably cultivate at least 0.2 million ha by 2030. This is possible, as there is no need for building expensive dams nor schemes. The only thing needed are small interest-free loans - indeed, one million loans of US$ 1,000 at most. And farmers will be able to pay it all back, within 3 years. It can be done. So let’s do it!
Guest
Guest - Gerardo van Halsema on Thursday, 16 January 2025 09:31
access to water storage

Thanks Pieter for your interesting and valuable comment.
Focussing on farmer led and nature based irrigation development is indeed a valuable direction to pursue in increasing agricultural productivity. The question boils down to land v water productivity/intensification. Increasing irrigation will also increase water consumption by agriculture, not necessarily affecting water productivity. We have seen a massive increase in extensive rainfed agriculture for cereals in Africa (low input, low yield), which affects water consumption and land use. So, intensifying irrigated land to hold expansion of extensification may be a valuable trade off to make, even if it increases water consumption of irrigated area. If done well, it may provide farmers with enough water security to invest in fertility, weed management and crop protection measures that may increase WP. (This might be nice to assess.)
Two caveats remain: (i) to what extent does conversion to irrigation lead to a conversion to higher value non-cereal crops (improving livelihoods but retaining pressure on rainfed cereal production); (ii) who gains access to irrigated plots (does it replace rainfed or is it an additional source that may also feed further expansion in rainfed?).
The dilemma still remains; we can make improvements at the livelihood level, but can we also attain these at the resources management level? Can we indeed produce more, with less?

Thanks Pieter for your interesting and valuable comment. Focussing on farmer led and nature based irrigation development is indeed a valuable direction to pursue in increasing agricultural productivity. The question boils down to land v water productivity/intensification. Increasing irrigation will also increase water consumption by agriculture, not necessarily affecting water productivity. We have seen a massive increase in extensive rainfed agriculture for cereals in Africa (low input, low yield), which affects water consumption and land use. So, intensifying irrigated land to hold expansion of extensification may be a valuable trade off to make, even if it increases water consumption of irrigated area. If done well, it may provide farmers with enough water security to invest in fertility, weed management and crop protection measures that may increase WP. (This might be nice to assess.) Two caveats remain: (i) to what extent does conversion to irrigation lead to a conversion to higher value non-cereal crops (improving livelihoods but retaining pressure on rainfed cereal production); (ii) who gains access to irrigated plots (does it replace rainfed or is it an additional source that may also feed further expansion in rainfed?). The dilemma still remains; we can make improvements at the livelihood level, but can we also attain these at the resources management level? Can we indeed produce more, with less?
Guest
Guest - Sandra Megens on Wednesday, 15 January 2025 19:13
No negotiation, not compromise in LAC

In Latin America, where agriculture is predominantly managed and sustained by indigenous communities, greater inclusivity is essential to understand conditions and challenges at the ground level fully. The exclusion of traditional agricultural practices from policy decisions has significantly constrained efforts to promote efficient and climate-resilient systems. These conventional systems, characterized by diverse, locally adapted crops and techniques, are both sustainable and resilient to climate shocks. Ignoring their value not only marginalizes the critical contributions of indigenous knowledge but also opportunities to develop holistic solutions that address resource depletion and environmental degradation. This oversight ultimately hampers progress toward achieving global sustainability and food security goals.
Furthermore, while policy frameworks may present a seemingly comprehensive and well-structured approach to food security, their implementation often tells a different story. On paper, policies may align with sustainability goals and inclusivity, but in practice, they frequently fail to address the realities on the ground. This disconnect undermines efforts to promote food security, particularly when traditional agricultural practices and localized needs are excluded (Ecuadorian case), specifically in transboundary regions. Effective solutions require bridging this gap between policy design and practical application to ensure meaningful progress toward sustainable and equitable food systems.

In Latin America, where agriculture is predominantly managed and sustained by indigenous communities, greater inclusivity is essential to understand conditions and challenges at the ground level fully. The exclusion of traditional agricultural practices from policy decisions has significantly constrained efforts to promote efficient and climate-resilient systems. These conventional systems, characterized by diverse, locally adapted crops and techniques, are both sustainable and resilient to climate shocks. Ignoring their value not only marginalizes the critical contributions of indigenous knowledge but also opportunities to develop holistic solutions that address resource depletion and environmental degradation. This oversight ultimately hampers progress toward achieving global sustainability and food security goals. Furthermore, while policy frameworks may present a seemingly comprehensive and well-structured approach to food security, their implementation often tells a different story. On paper, policies may align with sustainability goals and inclusivity, but in practice, they frequently fail to address the realities on the ground. This disconnect undermines efforts to promote food security, particularly when traditional agricultural practices and localized needs are excluded (Ecuadorian case), specifically in transboundary regions. Effective solutions require bridging this gap between policy design and practical application to ensure meaningful progress toward sustainable and equitable food systems.
Chris Seijger on Tuesday, 21 January 2025 08:45
Attention for traditional agricultural practices

Attention for traditional agricultural practices

Dear Sandra Megens,

Thanks a lot for making this point, indeed traditional agricultural practices have a lot to offer in terms of climate-resilience, nutrition, biodiversity and sustainability. In the last decades attention has mostly gone to high-yielding varieties to feed our planet, but as we also discuss in our paper, we increasingly see the limits of these high-yielding varieties (their yields level off partly due to more extreme climates, feed + fuel crops demand an awful lot of land and water at the expense of nature and vulnerable communities), which is also why we advocate the use of underutilized, more traditional crops. Traditional crops should thus indeed deserve much more attention in achieving regional goals of food security and biodiversity.

The disconnect you mention between holistic policies on paper, and poor implementation in practice requires constant attention. Pointing out these disconnects, keeping decision-makers accountable for their decisions and policies, while showcasing feasible, more inclusive alternatives is adamant. Especially as we now know that the potential and promises to increase agricultural production on fewer land and with less water turn out to be mostly empty.

Attention for traditional agricultural practices Dear Sandra Megens, Thanks a lot for making this point, indeed traditional agricultural practices have a lot to offer in terms of climate-resilience, nutrition, biodiversity and sustainability. In the last decades attention has mostly gone to high-yielding varieties to feed our planet, but as we also discuss in our paper, we increasingly see the limits of these high-yielding varieties (their yields level off partly due to more extreme climates, feed + fuel crops demand an awful lot of land and water at the expense of nature and vulnerable communities), which is also why we advocate the use of underutilized, more traditional crops. Traditional crops should thus indeed deserve much more attention in achieving regional goals of food security and biodiversity. The disconnect you mention between holistic policies on paper, and poor implementation in practice requires constant attention. Pointing out these disconnects, keeping decision-makers accountable for their decisions and policies, while showcasing feasible, more inclusive alternatives is adamant. Especially as we now know that the potential and promises to increase agricultural production on fewer land and with less water turn out to be mostly empty.
Guest
Guest - Brian Chatterton on Thursday, 16 January 2025 07:39
Water managers need to learn more about farming

We have an unfortunate division between water managers who try to manage the resource and the use managers (the farmers) who convert that water into a product. As a farmer myself i have found it that the resource managers find it difficult to understand farming problems. For example in many regions farmers are told to sow early so they crop grows using more natural rainfall and less irrigation. The crop matures before the the hottest part of summer. I try to explain that early sowing needs improved weed control and we need to work with farmers to achieve that otherwise early sowing means low yields.

We have an unfortunate division between water managers who try to manage the resource and the use managers (the farmers) who convert that water into a product. As a farmer myself i have found it that the resource managers find it difficult to understand farming problems. For example in many regions farmers are told to sow early so they crop grows using more natural rainfall and less irrigation. The crop matures before the the hottest part of summer. I try to explain that early sowing needs improved weed control and we need to work with farmers to achieve that otherwise early sowing means low yields.
Chris Seijger on Tuesday, 21 January 2025 08:43
water managers and limited lack of farming knowledge

Dear Brian Chatterton,

Water managers try to cater to many interests, including farming but also providing sufficient water for other consumptive users (drinking water, industry, nature), and serving those interests in times of water stress and excess.

Changing planting dates is indeed often mentioned as a response to reduce irrigation requirements. Is the weed control difficult to implement by farmers in your region, or does it require a small shift in farming practices when farmers realise it increases their yields? What are your experiences in working otgether with farmers, are the farmers organised in a water user association, or are there other informal farmer networks to discuss (effective!) changes to adapt to reduced irrigation volumes while securing sufficient yields?

Dear Brian Chatterton, Water managers try to cater to many interests, including farming but also providing sufficient water for other consumptive users (drinking water, industry, nature), and serving those interests in times of water stress and excess. Changing planting dates is indeed often mentioned as a response to reduce irrigation requirements. Is the weed control difficult to implement by farmers in your region, or does it require a small shift in farming practices when farmers realise it increases their yields? What are your experiences in working otgether with farmers, are the farmers organised in a water user association, or are there other informal farmer networks to discuss (effective!) changes to adapt to reduced irrigation volumes while securing sufficient yields?
Guest
Guest - Colin Steley on Tuesday, 21 January 2025 01:37
There is considerable potential to increase irrigated crop water productivity (CWP), often appreciably ........

https://www.water-alternatives.org/images/Forum/colin.png
Source: Figure 4.1 in https://www.fao.org/4/i1688e/i1688e.pdf.

[img]https://www.water-alternatives.org/images/Forum/colin.png[/img] Source: Figure 4.1 in https://www.fao.org/4/i1688e/i1688e.pdf.
Guest
Guest - Colin Steley on Tuesday, 21 January 2025 02:12
....., therefore, the question is, how to increase irrigated CWP in practice?

1. A previous blind spot was that, the large 'CWP' literature consistently assumed that actual crop evapotranspiration (ETa) and actual crop yield (Ya) are independent variables;

2. However, as Ya is primarily or directly dependent on ETa and agronomy, the main purpose of irrigation is to optimize ETa to optimize Ya and maximize CWP = Ya/ETa;

3. This CWP blind spot sabotaged previous 'CWP' applications;

Consistent evidence now indicates that:

5. CWP is low because Ya is low because ETa is low, and:

6. There is considerable potential to increase CWP (Ya/ETa), often appreciably, by governing and managing irrigation systems to optimize ETa and Ya and maximize CWP (Ya/ETa)

Source: https://www.researchgate.net/publication/375596355.

1. A previous blind spot was that, the large 'CWP' literature consistently assumed that actual crop evapotranspiration (ETa) and actual crop yield (Ya) are independent variables; 2. However, as Ya is primarily or directly dependent on ETa and agronomy, the main purpose of irrigation is to optimize ETa to optimize Ya and maximize CWP = Ya/ETa; 3. This CWP blind spot sabotaged previous 'CWP' applications; Consistent evidence now indicates that: 5. CWP is low because Ya is low because ETa is low, and: 6. There is considerable potential to increase CWP (Ya/ETa), often appreciably, by governing and managing irrigation systems to optimize ETa and Ya and maximize CWP (Ya/ETa) Source: https://www.researchgate.net/publication/375596355.
Chris Seijger on Thursday, 23 January 2025 11:09
scope to increase irrigated CWP in practice

Dear Colin Steley

Thanks for bringing this up. I find it difficult to respond to your points, as solid ET data is absent to pinpoint low and high CWP in rice, wheat and maize. Also, curves on yield-ETa relationships are hard to produce and find, due to this absence of reliable data.

Intuitively I agree that areas with low CWP may increase (a bit) under better management of water and fertilizers. But, against the bigger global trends we see already that irrigation intensification takes place massively in Asia, Latin America and MENA. How much water can then be saved, enough to cut down on unsustainable extraction rates, or even reallocated to other sectors? An interesting question I think!

Dear Colin Steley Thanks for bringing this up. I find it difficult to respond to your points, as solid ET data is absent to pinpoint low and high CWP in rice, wheat and maize. Also, curves on yield-ETa relationships are hard to produce and find, due to this absence of reliable data. Intuitively I agree that areas with low CWP may increase (a bit) under better management of water and fertilizers. But, against the bigger global trends we see already that irrigation intensification takes place massively in Asia, Latin America and MENA. How much water can then be saved, enough to cut down on unsustainable extraction rates, or even reallocated to other sectors? An interesting question I think!
Guest
Guest - David Molden on Tuesday, 21 January 2025 23:17
A wake up call for agricultural water management - still much more to do including productivity gains

I would like to congratulate and thank the Chris Seijger and co-authors for their work on re-visiting the scenarios of the Comprehensive Assessment (CA) of Water Management in Agriculture. The findings of the paper and the blog provided in the Water Alternatives Dissensus Forum provide an important wakeup call about water and food.

At the time of producing the CA we were indeed hopeful of limiting global expansion of land and water use for food. We were also hopeful that more investments in water could help fight poverty and malnutrition. The authors (Seijger et al, 2025) show that the gains we had hoped for did not occur, and the world continued the unsustainable track of expanding land and water use to produce enough food for a growing and hungrier population. In retrospect, this growth in land and water use is not too surprising given how the world has responded to climate change, malnutrition and biodiversity loss.

I appreciated the analysis of what happened, but there are alternate explanations about why it happened. Another explanation about why productivity gains did not happen is that investments and policies were not made to support such gains. The authors argue that the scope for productivity gains is limited, and present arguments based on biophysical grounds (potential gains already met, and the limited scope for reducing losses in irrigation). The CA and follow up work on water productivity (Molden et al, 2010) was also cautious in assessing water productivity gains for the same reasons, but at the same time, the CA assessed that gains could be made in irrigated areas showing low productivity, and through agricultural water management interventions in rainfed areas. I believe this is still the case. In this forum, Colin Steeley argues that there is still considerable scope for improvement. Pieter van der Zaag pointed to the need to focus on Africa to improve yields and resilience, and Gerardo van Halsema argues that better water security may lead to investments to improve water productivity in Africa.

While I agree with the recommendations on diet and nutrition and climate change, I was disappointed that the article downplayed the role of irrigation and agricultural water management itself. Follow up work of the CA showed the importance of diet to future water use (see Saving Water from Field to Fork by Lundqvist et al, 2008). Changing diets, like productivity gains, will continue to be difficult to realize, but still needs to happen.

We should not lose focus on the important work that needs to be done in Agricultural Water Management on many fronts including implementing water management solutions in areas of food insecurity and high poverty; reducing water consumption by agriculture in water-stressed basins (andd possibly dealing with a decline in agricultural production in these areas); realizing gains in land and water productivity in underperforming irrigated and rainfed areas; better governance, investments and policies to support these changes; and more. In this forum, Sandra Megens points to the need for better inclusivity and equity, and Brian Chatterton points to the disconnect between water managers and farmers. There is plenty to be done in the field of Agricultural Water Management.

I hope that other parts of the Comprehensive Assessment could be revisited, and that there will be new ideas and energy to make change happen. Thanks to the authors for opening this important discussion.


References:
Lundqvist, J., C. de Fraiture and D. Molden. Saving Water: From Field to Fork – Curbing Losses and Wastage in theFood Chain. SIWI Policy Brief. SIWI, 2008. .

Molden, D. J., Oweis, T., Steduto, P., Bindraban, P. S., Hanjra, A., & Kijne, J. (2010). Improving agricultural water productivity: Between optimism and caution. Agricultural Water Management, 97(2010), 528-535.

Seijger, C.; Urfels, A.; Christoforidou, M.; Hellegers, P.; Borghuis, G.; Langan, S. and van Halsema, G. 2025. More food, but less land and water for nature: Why agricultural productivity gains did not materialize. Agricultural Water Management 307(2025), https://doi.org/10.1016/j.agwat.2024.109229

I would like to congratulate and thank the Chris Seijger and co-authors for their work on re-visiting the scenarios of the Comprehensive Assessment (CA) of Water Management in Agriculture. The findings of the paper and the blog provided in the Water Alternatives Dissensus Forum provide an important wakeup call about water and food. At the time of producing the CA we were indeed hopeful of limiting global expansion of land and water use for food. We were also hopeful that more investments in water could help fight poverty and malnutrition. The authors (Seijger et al, 2025) show that the gains we had hoped for did not occur, and the world continued the unsustainable track of expanding land and water use to produce enough food for a growing and hungrier population. In retrospect, this growth in land and water use is not too surprising given how the world has responded to climate change, malnutrition and biodiversity loss. I appreciated the analysis of what happened, but there are alternate explanations about why it happened. Another explanation about why productivity gains did not happen is that investments and policies were not made to support such gains. The authors argue that the scope for productivity gains is limited, and present arguments based on biophysical grounds (potential gains already met, and the limited scope for reducing losses in irrigation). The CA and follow up work on water productivity (Molden et al, 2010) was also cautious in assessing water productivity gains for the same reasons, but at the same time, the CA assessed that gains could be made in irrigated areas showing low productivity, and through agricultural water management interventions in rainfed areas. I believe this is still the case. In this forum, Colin Steeley argues that there is still considerable scope for improvement. Pieter van der Zaag pointed to the need to focus on Africa to improve yields and resilience, and Gerardo van Halsema argues that better water security may lead to investments to improve water productivity in Africa. While I agree with the recommendations on diet and nutrition and climate change, I was disappointed that the article downplayed the role of irrigation and agricultural water management itself. Follow up work of the CA showed the importance of diet to future water use (see Saving Water from Field to Fork by Lundqvist et al, 2008). Changing diets, like productivity gains, will continue to be difficult to realize, but still needs to happen. We should not lose focus on the important work that needs to be done in Agricultural Water Management on many fronts including implementing water management solutions in areas of food insecurity and high poverty; reducing water consumption by agriculture in water-stressed basins (andd possibly dealing with a decline in agricultural production in these areas); realizing gains in land and water productivity in underperforming irrigated and rainfed areas; better governance, investments and policies to support these changes; and more. In this forum, Sandra Megens points to the need for better inclusivity and equity, and Brian Chatterton points to the disconnect between water managers and farmers. There is plenty to be done in the field of Agricultural Water Management. I hope that other parts of the Comprehensive Assessment could be revisited, and that there will be new ideas and energy to make change happen. Thanks to the authors for opening this important discussion. References: Lundqvist, J., C. de Fraiture and D. Molden. Saving Water: From Field to Fork – Curbing Losses and Wastage in theFood Chain. SIWI Policy Brief. SIWI, 2008. . Molden, D. J., Oweis, T., Steduto, P., Bindraban, P. S., Hanjra, A., & Kijne, J. (2010). Improving agricultural water productivity: Between optimism and caution. Agricultural Water Management, 97(2010), 528-535. Seijger, C.; Urfels, A.; Christoforidou, M.; Hellegers, P.; Borghuis, G.; Langan, S. and van Halsema, G. 2025. More food, but less land and water for nature: Why agricultural productivity gains did not materialize. Agricultural Water Management 307(2025), https://doi.org/10.1016/j.agwat.2024.109229
Chris Seijger on Thursday, 23 January 2025 11:33
wakeup call water and food

Dear David Molden,

Thanks a lot for your response, I greatly admire the depth and comprehensiveness of the Comprehensive Assessment, and think that the discussion we now have on this Forum is stimulating us and others to think beyond the CA and our paper that assessed where the world is heading in the light of the scenarios.

There are a few points I like to make:

1) we did not revisit the scenarios of the CA but just tried to assess what progress the world made in the light of the various scenarios of the CA.

2) I partly agree to your notion that investments and policies were not made to support gains in land and water productivity. Claudia Ringler made a bit of a similar statement on LinkedIn when commenting on our article. I agree in the sense that no major crop water productivity programme was funded, but I disagree in the sense that in the last 25 years a lot of money has been invested in higher yields and increased food security world wide. This resulted in a very very modest yield increase, and signals to us that the scope to increase yields (and with that also CWP possibly) is limited and much lower then originally hoped.

3) I agree there is scope to improve the role of irrigation and agricultural water management, both in rainfed and irrigated agriculture, but the scope is much less then originally anticipated and we like to be cautious and flag that in order to avoid (a continuation) of unrealistic expectations about the size of gains to be made realistically. To be more radical even, we might slowly move into the era that gains are not so secure anymore and rather stabilization would already be an accomplishment in regions with increased climate extremes and severe water stress?

4) Your point on further revisiting the Comprehensive Assessment I agree to very much, and as co-authors we have also been discussing this idea. From 2007 to 2025 the global challenges have become more pressing (rising population, climate change), more land and water is taken out of the global equation with biofuel, there is limited scope to improve land and water productivity, so the big question is out on the table ' what to do next?' What kind of scenarios, policy interventions, investment agendas, investment commitments are needed in the next 25 years?

Thanks again for all your work!

Dear David Molden, Thanks a lot for your response, I greatly admire the depth and comprehensiveness of the Comprehensive Assessment, and think that the discussion we now have on this Forum is stimulating us and others to think beyond the CA and our paper that assessed where the world is heading in the light of the scenarios. There are a few points I like to make: 1) we did not revisit the scenarios of the CA but just tried to assess what progress the world made in the light of the various scenarios of the CA. 2) I partly agree to your notion that investments and policies were not made to support gains in land and water productivity. Claudia Ringler made a bit of a similar statement on LinkedIn when commenting on our article. I agree in the sense that no major crop water productivity programme was funded, but I disagree in the sense that in the last 25 years a lot of money has been invested in higher yields and increased food security world wide. This resulted in a very very modest yield increase, and signals to us that the scope to increase yields (and with that also CWP possibly) is limited and much lower then originally hoped. 3) I agree there is scope to improve the role of irrigation and agricultural water management, both in rainfed and irrigated agriculture, but the scope is much less then originally anticipated and we like to be cautious and flag that in order to avoid (a continuation) of unrealistic expectations about the size of gains to be made realistically. To be more radical even, we might slowly move into the era that gains are not so secure anymore and rather stabilization would already be an accomplishment in regions with increased climate extremes and severe water stress? 4) Your point on further revisiting the Comprehensive Assessment I agree to very much, and as co-authors we have also been discussing this idea. From 2007 to 2025 the global challenges have become more pressing (rising population, climate change), more land and water is taken out of the global equation with biofuel, there is limited scope to improve land and water productivity, so the big question is out on the table ' what to do next?' What kind of scenarios, policy interventions, investment agendas, investment commitments are needed in the next 25 years? Thanks again for all your work!
Bruce Lankford on Wednesday, 22 January 2025 13:08
On stepping up global irrigation research

Dear Chris – congrats again on a very stimulating paper and also congrats for this excellent Forum dissensus on the same topic. I also will stick with dimensions around irrigation management, productivity and efficiency - rather than rainfed ag.

Agreeing with other contributors to this discussion, I believe the 2007 Comprehensive Assessment and your co-authored 2024 study should be seen as the wake-up call, invitation and precursor of a major piece of research about the means, nature and degree of land and water productivity/production gains both in the past 20-30 years and looking forward to the next 20-30 years.

Regarding this future irrigation research, I believe we have not fully triangulated, and controlled for, what explains irrigation performance because this needs us to more fully know the dynamics of resource inputs (e.g. land ha, water withdrawals and depletion), resource processing (e.g. crop and soil management, irrigation scheduling), outputs (e.g. yield/ha, total yields, yields/m3) and influencing factors (e.g. policies, prices & farmer practices.) These gaps mean we are currently relying on relatively malleable or single-scale data from satellite imagery, farmer reports and official statistics to gauge what is going on. Unless I am mistaken, I can’t see where the systematic data collection and synthesis is occurring to make accurate judgements about the performance of irrigated food systems.

This systematic research is difficult to do because of the nested scales and multiple sources of water found in irrigation. Meaning changes occur at the crop, field, farm, irrigation system, catchment and global levels, and over different time slots from days to years, and from different types of water (rain, soil water, groundwater, surface water, stored water and wastewater) that make it difficult to discern what has caused what. For example we know, it is possible save water at the field level within a cropping season of 100 days, but not at the catchment level over one year. Such detailed research is also difficult to do as it implies the need for lots of measurements and recording. But I think otherwise; we need instead smarter ways of getting optimal amounts of data that are auto-processed quickly into management and performance information.

To arrive at smarter ways of data analysis and synthesis, we need research in turn guided by accurate models and explanations of the relevant dynamics of irrigated systems. However, although there are models and explanations that attempt to grapple with time and space complexities in irrigation, I believe they do not go far enough. For example they do not fully account for how irrigators are able to expand water consumption land and crop production whilst sticking with their original water rights and withdrawals. In other words, in some places in the world, farmers have been able to ratchet up crop production, and sustain production through droughts, because they have been increasingly parsimonious with water on a per-hectare level but greater water consumers at the farm and/or catchment level via expanding land under production. Crucially (in my experience) this has not been via the current mainstream explanations of irrigators reusing drainage flows. Thus, to my mind the research community is a long way off from agreeing how to model and explain irrigation efficiency, water savings and pareto-maintained crop production. Until that happens we are being guided by quite simple models and explanations (see Lankford et al., 2023; Lankford, 2023 for some thoughts on this.

Alongside, and informed by, research – we need a wholly refreshed global architecture for supporting irrigators. We know that with some exceptions (such as letting farmers progress matters through FLID which in my view will not be very sustainable, or clumsy approaches to revitalising irrigation e.g. using drip), systematic approaches to irrigation that are water depletion-constraining (or contracting) and productivity-boosting are not being developed by researchers, donors and governments. To develop such an architecture will need action research that looks at what is working across the world, and what enhancements can be made. Possible examples that come to mind are in (Denison et al., 2022; Lankford et al., 2016; Renault et al., 2007)

To summarise, and as other contributors have said, we have every reason to be optimistic about future land and water production / productivity gains provided we acknowledge how complex irrigation and irrigation hydrology are, and respond to this complexity with appropriately resourced action-research programmes. I believe that until that happens irrigation will keep colonising land and water.

Well done again Chris, and the next time we meet in person, lets hope there is time for a coffee or beer.

Denison, J. A., Malerbe, F. D., Saura, P. P., Dressayre, E., Amjad, E., & Valieva, S. (2022). The Irrigation Operator of the Future: A Toolkit-Information Pack for Irrigation Service Delivery Performance Assessment and Planning. W. Bank. https://documents1.worldbank.org/curated/en/099537308252239234/pdf/IDU0b823b4db02ab4047f308f4208c4deb4d7e98.pdf
Lankford, B., Makin, I., Matthews, N., McCornick, P. G., Noble, A., & Shah, T. (2016). A compact to revitalise large-scale irrigation systems using a leadership-partnership-ownership'theory of change'. Water Alternatives, 9(1), 1-32. http://www.water-alternatives.org/index.php/alldoc/articles/302-a9-1-1/file
Lankford, B., Pringle, C., McCosh, J., Shabalala, M., Hess, T., & Knox, J. W. (2023). Irrigation area, efficiency and water storage mediate the drought resilience of irrigated agriculture in a semi-arid catchment. Science of the Total Environment, 859, 160263. https://doi.org/10.1016/j.scitotenv.2022.160263" target="_blank" rel="nofollow">https://doi.org/https://doi.org/10.1016/j.scitotenv.2022.160263
Lankford, B. A. (2023). Resolving the paradoxes of irrigation efficiency: Irrigated systems accounting analyses depletion-based water conservation for reallocation. Agricultural Water Management, 287, 108437. https://doi.org/10.1016/j.agwat.2023.108437" target="_blank" rel="nofollow">https://doi.org/https://doi.org/10.1016/j.agwat.2023.108437
Renault, D., Facon, T., & Wahaj, R. (2007). Modernizing irrigation management - the MASSCOTE approach. Mapping System and Services for Canal Operation Techniques (FAO Irrigation and Drainage Paper 63., Issue. Food and Agriculture Organization of the United Nations. https://www.fao.org/4/a1114e/a1114e.pdf


Dear Chris – congrats again on a very stimulating paper and also congrats for this excellent Forum dissensus on the same topic. I also will stick with dimensions around irrigation management, productivity and efficiency - rather than rainfed ag. Agreeing with other contributors to this discussion, I believe the 2007 Comprehensive Assessment and your co-authored 2024 study should be seen as the wake-up call, invitation and precursor of a major piece of research about the means, nature and degree of land and water productivity/production gains both in the past 20-30 years and looking forward to the next 20-30 years. Regarding this future irrigation research, I believe we have not fully triangulated, and controlled for, what explains irrigation performance because this needs us to more fully know the dynamics of resource inputs (e.g. land ha, water withdrawals and depletion), resource processing (e.g. crop and soil management, irrigation scheduling), outputs (e.g. yield/ha, total yields, yields/m3) and influencing factors (e.g. policies, prices & farmer practices.) These gaps mean we are currently relying on relatively malleable or single-scale data from satellite imagery, farmer reports and official statistics to gauge what is going on. Unless I am mistaken, I can’t see where the systematic data collection and synthesis is occurring to make accurate judgements about the performance of irrigated food systems. This systematic research is difficult to do because of the nested scales and multiple sources of water found in irrigation. Meaning changes occur at the crop, field, farm, irrigation system, catchment and global levels, and over different time slots from days to years, and from different types of water (rain, soil water, groundwater, surface water, stored water and wastewater) that make it difficult to discern what has caused what. For example we know, it is possible save water at the field level within a cropping season of 100 days, but not at the catchment level over one year. Such detailed research is also difficult to do as it implies the need for lots of measurements and recording. But I think otherwise; we need instead smarter ways of getting optimal amounts of data that are auto-processed quickly into management and performance information. To arrive at smarter ways of data analysis and synthesis, we need research in turn guided by accurate models and explanations of the relevant dynamics of irrigated systems. However, although there are models and explanations that attempt to grapple with time and space complexities in irrigation, I believe they do not go far enough. For example they do not fully account for how irrigators are able to expand water consumption land and crop production whilst sticking with their original water rights and withdrawals. In other words, in some places in the world, farmers have been able to ratchet up crop production, and sustain production through droughts, because they have been increasingly parsimonious with water on a per-hectare level but greater water consumers at the farm and/or catchment level via expanding land under production. Crucially (in my experience) this has not been via the current mainstream explanations of irrigators reusing drainage flows. Thus, to my mind the research community is a long way off from agreeing how to model and explain irrigation efficiency, water savings and pareto-maintained crop production. Until that happens we are being guided by quite simple models and explanations (see Lankford et al., 2023; Lankford, 2023 for some thoughts on this. Alongside, and informed by, research – we need a wholly refreshed global architecture for supporting irrigators. We know that with some exceptions (such as letting farmers progress matters through FLID which in my view will not be very sustainable, or clumsy approaches to revitalising irrigation e.g. using drip), systematic approaches to irrigation that are water depletion-constraining (or contracting) and productivity-boosting are not being developed by researchers, donors and governments. To develop such an architecture will need action research that looks at what is working across the world, and what enhancements can be made. Possible examples that come to mind are in (Denison et al., 2022; Lankford et al., 2016; Renault et al., 2007) To summarise, and as other contributors have said, we have every reason to be optimistic about future land and water production / productivity gains provided we acknowledge how complex irrigation and irrigation hydrology are, and respond to this complexity with appropriately resourced action-research programmes. I believe that until that happens [url=https://brucelankford.org.uk/2024/10/22/irrigation-is-colonising-water-and-is-being-colonised/]irrigation will keep colonising land and water[/url]. Well done again Chris, and the next time we meet in person, lets hope there is time for a coffee or beer. Denison, J. A., Malerbe, F. D., Saura, P. P., Dressayre, E., Amjad, E., & Valieva, S. (2022). The Irrigation Operator of the Future: A Toolkit-Information Pack for Irrigation Service Delivery Performance Assessment and Planning. W. Bank. https://documents1.worldbank.org/curated/en/099537308252239234/pdf/IDU0b823b4db02ab4047f308f4208c4deb4d7e98.pdf Lankford, B., Makin, I., Matthews, N., McCornick, P. G., Noble, A., & Shah, T. (2016). A compact to revitalise large-scale irrigation systems using a leadership-partnership-ownership'theory of change'. Water Alternatives, 9(1), 1-32. http://www.water-alternatives.org/index.php/alldoc/articles/302-a9-1-1/file Lankford, B., Pringle, C., McCosh, J., Shabalala, M., Hess, T., & Knox, J. W. (2023). Irrigation area, efficiency and water storage mediate the drought resilience of irrigated agriculture in a semi-arid catchment. Science of the Total Environment, 859, 160263. https://doi.org/https://doi.org/10.1016/j.scitotenv.2022.160263 Lankford, B. A. (2023). Resolving the paradoxes of irrigation efficiency: Irrigated systems accounting analyses depletion-based water conservation for reallocation. Agricultural Water Management, 287, 108437. https://doi.org/https://doi.org/10.1016/j.agwat.2023.108437 Renault, D., Facon, T., & Wahaj, R. (2007). Modernizing irrigation management - the MASSCOTE approach. Mapping System and Services for Canal Operation Techniques (FAO Irrigation and Drainage Paper 63., Issue. Food and Agriculture Organization of the United Nations. https://www.fao.org/4/a1114e/a1114e.pdf
Chris Seijger on Thursday, 23 January 2025 12:47
on stepping up global irrigation research

Hi Bruce

Thanks a lot for sketching out these optimistic future research directions for irrigation. I fully agree to your arguments that we have very limited data to assess irrigation at plot, farm, watershed river basin scale, making it hard to correctly guestimate the potential of gains. A point I also tried to make in my response to Colin Steley.

At this point I notice that in the discussion forum most attention goes to irrigation, whereas rainfed agriculture and global trade were also widely covered in the Comprehensive Assessment and our analysis. Curious what others think of future development directions in these two domains.

And Bruce, yes next time we meet in person it would be nice to shake hands properly and have a cold or warm watery drink

Hi Bruce Thanks a lot for sketching out these optimistic future research directions for irrigation. I fully agree to your arguments that we have very limited data to assess irrigation at plot, farm, watershed river basin scale, making it hard to correctly guestimate the potential of gains. A point I also tried to make in my response to Colin Steley. At this point I notice that in the discussion forum most attention goes to irrigation, whereas rainfed agriculture and global trade were also widely covered in the Comprehensive Assessment and our analysis. Curious what others think of future development directions in these two domains. And Bruce, yes next time we meet in person it would be nice to shake hands properly and have a cold or warm watery drink :)
Guest
Guest - Pallavi Bharadwaj on Wednesday, 22 January 2025 17:50
Fits right with GWB's Ghana Precise Irrigation Framework project

This is insightful and interesting https://seg.org/gwb_projects/ghana/

This is insightful and interesting https://seg.org/gwb_projects/ghana/
Chris Seijger on Thursday, 23 January 2025 12:51
Ghana's precise irrigation framework project

Dear Pallavi Bharadwaj

Glad you find the blogpost and conducted analysis relevant for efforts to implement in Ghana precise irrigation!

Dear Pallavi Bharadwaj Glad you find the blogpost and conducted analysis relevant for efforts to implement in Ghana precise irrigation!
Guest
Saturday, 08 February 2025

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