Managing water scarcity in European and Chinese cropping systems

To summarise the results of the SHui project, our consortium gathered for one last time on 12 / 13 July 2022 in Brussels near to the European Parliament, to ensure our meeting was available to our EU project Officer.

Initially, our project co-ordinator Jose Gomez (IAS-CSIC, Spain) introduced the project, which capitalised on data provided by a long-term research and monitoring platform (spanning many partners) to further develop crop and hydrological models to determine impacts on soil moisture and crop yields across range of scales (plot, farm and regional). Two key objectives were to develop Best Management Practices (BMPs) to implement under different farming conditions and determine the costs / benefits, while projecting the impacts of these at much larger scales. These objectives set the scene for a series of technical talks that summarised the key results of the project (see programme below).

Juan Jose Alarcón (CEBAS-CSIC, Spain) introduced the potential of deficit irrigation to increase horticultural water use efficiency, with its implementation facilitated by the use of various soil and plant sensors and different crop management zones to allow precision irrigation. Tomas Dostal (CTU Czech Republic) discussed rainfall simulation experiments and mathematical modelling that evaluated the impact of BMPs in different locations (climates) throughout Europe, Israel and China. Mulching especially increased soil water storage up to 5%, while contour tillage, no till and cover crops decreased runoff and sediment load by up to 80%. Gianni Quaranta (UNIBAS-MEDES, Italy) then provided a cost-benefit analysis of applying some of these techniques, demonstrating the connectivity of economic and farm environmental efficiency. Lastly, Gabrielle de Lannoy (KU Leuven, Belgium) utilised advances in remote sensing and regional scale crop modelling to project that Europe’s net irrigation requirement may increase by 30% by the end of the century if climate change continues apace.

Before the coffee break, Ian Dodd (Lancaster, UK) reflected on the challenges of cross-continent collaboration in pandemic times, discussing different models of EU-China engagement while highlighting SHui’s dissemination achievements. After the coffee break, Rosanna Salvia (UNIBAS-MEDES, Italy) provides some insights and recommendations arising not just from the technical work conducted with SHui, but from our engagement with farmer  focus groups, highlighting that European policies must incentivise practices to allow a transition to more sustainable farming.

A round table participatory discussion then ensued on how to optimise water use in agriculture, moderated by our project co-ordinator Jose Gomez (IAS-CSIC, Spain) with contributions from:

  • Miguel Barnuevo (Union de Pequenos Agricultores, Spain)
  • Ana Mª Ferrer (Fenacore, Spain)
  • Tim Hess (representing to UK Irrigation Association)
  • Dirk Raes (KU Leuven, Belgium)

On the following day, the consortium met to refine plans for the delivery of the project results both to the European Commission, and to our wider stakeholder group.

Agenda of the meeting available here.

Recording of the meeting here.




Authors: Huntenburg, Katharina; Puertolas, Jaime; de Ollas, Carlos; Dodd, Ian C.


While the importance of plant water relations in determining crop response to soil water availability is difficult to over-emphasise, under many circumstances, plants maintain their leaf water status as the soil dries yet shoot gas exchange and growth is restricted. Such observations lead to development of a paradigm that root-to-shoot signals regulate shoot physiology, and a conceptual framework to test the importance of different signals such as plant hormones in these physiological processes. Nevertheless, shoot-to-root (hormonal) signalling also plays an important role in regulating root growth and function and may dominate when larger quantities of a hormone are produced in the shoots than the roots. Here, we review the evidence for acropetal and basipetal transport of three different plant hormones (abscisic acid, jasmonates, strigolactones) that have antitranspirant effects, to indicate the origin and action of these signalling systems. The physiological importance of each transport pathway likely depends on the specific environmental conditions the plant is exposed to, specifically whether the roots or shoots are the first to lose turgor when exposed to drying soil or elevated atmospheric demand, respectively. All three hormones can interact to influence each other’s synthesis, degradation and intracellular signalling to augment or attenuate their physiological impacts, highlighting the complexity of unravelling these signalling systems. Nevertheless, such complexity suggests crop improvement opportunities to select for allelic variation in the genes affecting hormonal regulation, and (in selected crops) to augment root–shoot communication by judicious selection of rootstock–scion combinations to ameliorate abiotic stresses.

Read the full paper here.


Authors: Tian, Peng; Liu, Likun; Tian, Xiaojing; Zhao, Guangju; Klik, Andreas; Wang, Ruidong; Lu, Xiaoyan; Mu, Xingmin; Bai, Yunpeng


Assessing regional sediment yield variation and their responses to the potential controlling factors are critical to develop specific strategies of soil conservation measures to adapt to future climate change. This study attempted to investigate the spatial–temporal variation of sediment load in the Wei River basin in the midstream of the Yellow River during 1961–2015 at 15 hydrological stations. The results indicated that annual sediment load in the past six decades decreased significantly (P < 0.01) with the changing trends of −6.43 × 104, −3.86 × 104, −4.6 × 104t/a at Xianyang, Zhangjiashan, and Zhuangtou stations, respectively. Annual sediment load exhibited abrupt changes in the mid-1990s, which were largely attributed to the strong effects of soil conservation measures in the study area. The spatial pattern of soil erosion were characterized by high sediment yield in the north with sparse vegetation cover and well-developed gullies, and low sediment yield in the south with flat plain and good vegetation cover in the Wei River basin. The results of the partial least squares-structural equation model (PLS-SEM) showed that vegetation changes and rainfall variability explained 62.3%, 47.3%, and 40.1% of the variation in runoff at Xianyang, Zhuangtou, and Zhangjiashan stations, respectively, whereas 59.4%, 17.6% and 48% of the variation in sediment load were explained by the combining effects of rainfall variability, changes of vegetation and runoff. This study provides a deep insight for understanding the effects of driving forces on sediment yield changes, and can be useful to regional soil conservation planning in the region.

Read the full paper here.

Our final SHui webinar occurred on 2 August, with Alon-Ben Gal (ARO)and Aviva Peeters (TerraVision Lab) showcasing the work they’ve done within WP4 in the area of precision irrigation, by developing models to delineate management zones and predict variability in crop water stress within a field. Over 50 participants from 13 different countries joined in across multiple time zones, with particular mention of those attending from the USA where it was 3 am in the morning !

After some scene-setting conceptual slides, Alon introduced a number of real-life examples from SHui partners (vineyards and peach orchards from Spain and Israel) where spatial data (soil, crop and satellite-based) discriminated different management zones, with their implementation increasing crop yield and quality in some examples but not others. Aviva then demonstrated how utilising easily accessible data (without requiring laborious manual in-field measurements) within new models developed within the project can improve the prediction of variables such as Crop Water Stress Index (CWSI), a Best Management Practice for irrigating vines and other crops.

A new web-based application (Precision Crop Water Management) for utilising spatial data was introduced, to show how input data (e.g. topography) can generate output data (e.g. CWSI) that farmers can use for irrigation management decisions. Watch this space for the release of this application later in the year.

Finally, a question and answer session dealt with the practicalities of applying these tools (e.g. accounting for irrigation inputs, the frequency at which management zones may need re-assigning) and possible impediments in their development or application (e.g. availability of researchers with data science and/or programming skills, the viability of implementation by commercial enterprises varying in size).

On the 15th of June 2022, the SHui’s Austrian team talked as part of a local agricultural school’s annual Courtyard and Paddock Festival held at LFS Obersiebenbrunn (LFS = Landwirtschaftliche Fachschule = agricultural school). This public event aims to appeal to graduates, students and their parents, and interested farmers. Around 25 people participated at a busy time of year for the farmers, and in competition with nice weather which prompted others to seek the shade for refreshments. Many of the students, future farmers, had finished their education as “agricultural skilled worker”, highlighting the need for up-to-date project results to be disseminated while these workers are still in education.

Reinhard Nolz gave a talk entitle “Landwirtschaftliches Wassermanagement – Grundlagen und Optimierungsmöglichkeiten” (in English “Agricultural water management – basics and optimization possibilities“) which contained results from the case study site Obersiebenbrunn, used in SHui. The talk contained contributions from Alba Canet Marti et al. (WaterAgri), Gunther Liebhard (SHui) and Angela Morales Santos, in cooperation with Margarita Garcia-Vila and Reinhard Nolz from SHui.

The erosion laboratory from the Institute for Sustainable Agriculture (IAS-CSIC) attended to the last European Geosciences Union General Assembly, hold in Vienna during May, 23-27th. In this conference, José A. Gómez and Gema Guzmán presented and discussed some of the results from different soil erosion plots set up in two contrasting olive orchards at southern Spain.

In these trials, runoff, soil loss and a set of soil properties have been monitored under different ground cover managements since early 2000s. More information about this research can be found at:

How does a vertic soil move? Soil erosion rates and its redistribution in an olive orchard at the medium-term:

Long-term hydrologic effect of temporary cover crops in an olive orchard on a sandy-loamy soil:

During their visit to Vienna, they had the chance of visiting some of the experiments carried out by the BOKU partners thanks to Stefan Strohmeier and to participate in the International Study Day on Tracing nicely organised by Sabine Karaushaar and Olivier Evrard.

Runoff plots at Mistelbach; photos: G. Guzmán.
Working group at the Tracing day at the University of Vienna; photos: O. Evrard.
Benacazón (Seville) site; photo: J.A. Gómez




Authors: Gomez, Jose A.; Reyna-Bowen, Lizardo; Fernandez Rebollo, Pilar; Soriano, Maria-Auxiliadora


This study presents an evaluation of soil organic carbon (SOC) and stock (SOCstock) for the whole rooting depth (60 cm), spaced 55 months in two adjacent olive orchards with similar conditions but different tree densities: (i) intensive, planted in 1996 at 310 tree ha−1; (ii) superintensive, planted in 2000 at 1850 tree ha−1. This was carried out to test the hypothesis that olive orchards at different plant densities will have different rates of accumulation of SOC in the whole soil rooting depth. SOC increased significantly in the superintensive orchard during the 55-month period, from 1.1 to 1.6% in the lane area, and from 1.2 to 1.7% in the tree area (average 0–60 cm), with a significant increase in SOCstock from 4.7 to 6.1 kg m−2. In the intensive orchard, there was not a significant increase in SOCstock in 0–60 cm, average of 4.06 and 4.16 kg m−2 in 2013 and 2018, respectively. Results indicate a potential for a significant increase in SOC and SOCstock in olive orchards at higher tree densities when combined with temporary cover crops and mulch of chopped pruning residues. The increase is associated with an increase in SOC, mainly at a 0–15 cm depth. Results also point to the need for improve our monitoring capabilities to detect moderate increases in SOC.

Read the full paper here.

In Annals of Botany

Authors: Valenzuela, Francisco Jose; Reineke, Daniela; Leventini, Dante; Chen, Christopher Cody Lee; Barrett-Lennard, Edward G.; Colmer, Timothy D.; Dodd, Ian C.; Shabala, Sergey; Brown, Patrick; Bazihizina, Nadia


Soil salinity, in both natural and managed environments, is highly heterogeneous, and understanding how plants respond to this spatiotemporal heterogeneity is increasingly important for sustainable agriculture in the era of global climate change. While the vast majority of research on crop response to salinity utilizes homogeneous saline conditions, a much smaller, but important, effort has been made in the past decade to understand plant molecular and physiological responses to heterogeneous salinity mainly by using split-root studies. These studies have begun to unravel how plants compensate for water/nutrient deprivation and limit salt stress by optimizing root-foraging in the most favourable parts of the soil.

This paper provides an overview of the patterns of salinity heterogeneity in rain-fed and irrigated systems. We then discuss results from split-root studies and the recent progress in understanding the physiological and molecular mechanisms regulating plant responses to heterogeneous root-zone salinity and nutrient conditions. We focus on mechanisms by which plants (salt/nutrient sensing, root-shoot signalling and water uptake) could optimize the use of less-saline patches within the root-zone, thereby enhancing growth under heterogeneous soil salinity conditions. Finally, we place these findings in the context of defining future research priorities, possible irrigation management and crop breeding opportunities to improve productivity from salt-affected lands.

Read the full paper here.


Authors: Pedrero Salcedo, Francisco; Perez Cutillas, Pedro; Alarcon Cabanero, Juan Jose; Vivaldi, Alessandro Gaetano


The global water crisis, driven by water scarcity and water quality deterioration, is expected to continue and intensify in dry and overpopulated areas, and will play a critical role in meeting future agricultural demands. Sustainability of agriculture irrigated with low quality water will require a comprehensive approach to soil, water, and crop management consisting of site- and situation-specific preventive measures and management strategies. Other problem related with water quality deterioration is soil salinization. Around 1Bha globally are salinized and soil salinization may be accelerating for several reasons including the changing climate. The consequences of climate change on soil salinization need to be monitored and mapped and, in this sense, remote sensing has been successfully applied to soil salinity monitoring. Although many issues remain to be resolved, some as important as the imbalance between ground-based measurements and satellite data. The main objective of this paper was to determine the influence of environmental factors on salinity from natural causes, and its effect on irrigated agriculture with degraded water. The study was developed on Campo de Cartagena, an intensive water-efficient irrigated area which main fruit tree is citrus (30%), a sensible crop to salinity. Nine representative citrus farms were selected, soil samples were analysed and different remote sensing indices and sets of environmental data were applied. Despite the heterogeneity between variables found by the descriptive analysis of the data, the relationship between farms, soil salinity and environmental data showed that applied salinity spectral indices were valid to detect soil salinity in citrus trees. Also, a set of environmental characterization provided useful information to determine the variables that most influence primary salinity in crops. Although the data extracted from spatial analysis indicated that to apply soil salinity predictive models, other variables related to agricultural management practices must be incorporated.

Read the full paper here.


Authors: Liebhard, Gunther; Klik, Andreas; Stumpp, Christine; Nolz, Reinhard


Stable isotope techniques can be used to investigate evapotranspiration and its partitioning into evaporation and transpiration. However, verification is often difficult due to missing information about actual evapotranspiration. Therefore, in this study a methodology tested for laboratory conditions was modified for field applications. Evapotranspiration, which was determined by weighing lysimeters, and isotope techniques were combined with soil water and lysimeter measurements to calculate evaporation and transpiration rates of soybean under natural conditions. The case study was conducted in 2019 in Groß-Enzersdorf, Austria. The results show that the methodology was suited to measure actual variations of evaporation and transpiration ratios, even during dry periods. Weekly evaporation (0.5–2.2 mm d−1) and transpiration (1.3–4.3 mm d−1) rates as well as the respective ratios (transpiration 43–85%) agreed with the results of numerical modelling and values from the literature, confirming the applicability of the modified methodology for portioning evapotranspiration in the field.

Read the full paper here.