Less water in agriculture? Potential and challenges in optimizing water use efficiency.

This article comments on: Turc B, Sahay S, Haupt J, de Oliveira Santos T, Bai G, Glowacka K. 2024. Up-regulation of non-photochemical quenching improves water use efficiency and reduces whole-plant water consumption under drought in Nicotianatabacum. Journal of Experimental Botany 75, 3959-3972.

How shifts in societal priorities link to reform in agricultural water management: Analytical framework and evidence from Germany, India and Tanzania.

Climate change, environmental awareness, and food security are just some of the new priorities societies pursue. Due to the very large influence of agriculture on water quantity and quality, often a certain degree of reform in agricultural water management is required to accommodate such new priorities. To assess the degree of reform an analytical framework is introduced to account for social (e.g. contestation, path dependency) and biophysical limitations (water balance as a zero-sum game, limited gains in biomass productivity) to reform in agricultural water management. The hypothesis tested in this paper is whether the framework is capable to link shifts in societal priorities to actual reform in agricultural water management and if the framework can assess to what extent agricultural water management has changed to accommodate shifting societal priorities. The analytical framework and variables assess ex-post the degree of a reorientation, which is understood as the interplay between shifts in societal priorities and reform in agricultural water management to accommodate such shifts. The framework offers a causal chain of 6 variables to assess a reorientation. A test is performed by probing the framework in diverse contexts of Germany, India and Tanzania. Evidence from Germany, India and Tanzania confirm the validity of the social and biophysical limitations as they acted as real boundaries for the amount of reform achieved. In Tanzania much reform was achieved and agricultural water management accommodated the new priority of agricultural expansion, whereas in Germany and India few farm-level changes were achieved making new priorities of environmental conservation unattainable. Based on the test it can be concluded that the framework offers a realistic lense to study reorientations around the world. For further research, in-depth case studies are recommended to further develop the framework and advance insight in the complex biophysical and social interrelationships of reorientations.

Food security under water scarcity: a comparative analysis of Egypt and Jordan.

Although there seems enough water available for our global food needs, there are large areas with growing water scarcity. Food security in these water scarce areas cannot be met through self-sufficiency. The only option is to become more dependent on food imports which is increasingly risky due to volatility in production and food prices. Before 2008, declining food prices and increasing global cereal production favoured the food import strategy. The 2008 world food crisis represented a shock to this strategy and renewed attention was paid to the self-sufficiency strategy. The aim of this paper is to compare the food security strategies of Egypt and Jordan, two water-stressed, increasingly populated, oil-poor countries, pre and post 2008, by means of a food-water analytical framework using FAOSTAT data. Findings show that Egypt and Jordan have many similarities in their food security situation as both are highly dependent on food imports (Egypt 50%, Jordan 95%), and both have a reduced capacity to absorb future price increases. As food imports are inevitable under the water scarce context of Egypt and Jordan, it is important to focus on how to cope with volatilities. Our analysis shows that Jordan has better absorbed the costs of rising food imports than Egypt and that Egypt is trapped by its high domestic cereal production. Having revealed the limited options available to water-scarce countries for food security, we discuss the potential of grain reserves to cope with future price hikes and production shocks. Supplementary Information: The online version contains supplementary material available at 10.1007/s12571-022-01310-y.

Water and sectoral policies in agriculture-forest frontiers: An expanded interdisciplinary research approach.

Major land use changes such as deforestation and restoration influence water resources in agriculture-forest landscapes. Changes are observed in water flows, groundwater infiltration, water quality and rainfall. Interdisciplinary water-forest research has unravelled biophysical parts of the interplay that influences forest and water resources. In this Perspective paper, we propose an expanded interdisciplinary research approach to study water and policies in agriculture-forest frontiers. The approach differs in four important aspects from previous ones: (i) a conceptual 'frontier' understanding; an analytical focus on (ii) agriculture and (iii) policy-water linkages; (iv) empirical attention to northern and southern countries. The approach is put into practice with the "Pendulum" framework, with interventions and the agriculture-forest frontier oscillating over time between exploitation and restoration. Through the approach, a better understanding will be provided on the dynamic interplay of water and policies in oscillating agriculture-forest frontiers, with changing outcomes for people and environment.

Intensifying saline water intrusion and drought in the Mekong Delta: From physical evidence to policy outlooks.

This paper assesses the recently intensified saline water intrusion (SI) and drought in the Vietnamese Mekong Delta (VMD). While the existing literature predominantly points the cause of drought to the hydropower dams in the upstream of the Mekong Basin, we contribute new physical evidence of the intensification of saline water intrusion (through backwater effect) in the VMD caused by three anthropogenic drivers: riverbed incision (due to both riverbed mining and dam construction), sea level rise and land subsidence. Thereupon, we highlight that it is critical to not underestimate the impacts from the localized factors, especially the riverbed-mining which can incise the channel by up to 15 cm/year and amplify the salinity intrusion. Our analysis is based on the extensive sets of hourly-to-daily hydrological time series from 11 gauge stations across the VMD. First, several signs of significantly increased tidal amplification (up to 66%) were revealed through the spectral analysis of the hourly water level data. This trend was further validated through the changes in slopes of the rating curves at the tidal zones, implying the relationships between the shift of the backwater effects on the rivers in VMD and the lowered water levels caused by the riverbed incision. Finally, we introduce a novel approach using the annual incision rates of the riverbed to compare four SI driving factors in terms of their relative contributions to the balance between fresh and saline water in the VMD.