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AbstractElevated CO2 concentration has been reported to decrease grain nutrient concentrations and thus worsen nutritional deficiency and hidden hunger. One nutritional aspect is mineral content, yet mineral bioavailability can be limited by the presence of phytic acid. Given that future climate scenarios predict elevated global temperature driven by elevated atmospheric CO2 concentrations, we used Temperature by Free‐Air CO2 Enrichment (T‐FACE) field experiments to investigate whether elevated temperature alters the effects of elevated CO2 on grain mineral concentrations, grain mineral yields, and their bioavailability in a range of wheat and rice genotypes. We found that the negative effects of elevated CO2 were compensated for by positive effects of elevated temperature. As a result, the combined elevated CO2 and elevated temperature increased concentrations of some minerals by up to ~15% in both rice and wheat relative to control conditions. Moreover, the combined elevated CO2 and elevated temperature did not significantly change total yields of some minerals despite lower grain yields. The combined CO2 and temperature elevation increased phytic acid concentration in rice by 18.1% but decreased it in wheat by 3.5%. The mineral bioavailability, estimated as the mole ratio of phytic acid to minerals in rice and wheat grains, was limited by the combined CO2 and temperature elevation in only a few cases. Our results indicate that under future climate conditions of elevated temperature and CO2, the nutritional quality of rice and wheat with respect to minerals may remain unchanged.

This report describes the modelling approach, input data, scenarios of biobased fertiliser application, and the results and conclusions in terms of environmental impacts. For all demonstration plants scenarios were worked out in terms of application rates of digestate and/or biobased fertilisers, and the associated applied nutrients and heavy metals to the soil. Thereafter, the model simulations were carried out which were discussed during a SYSTEMIC internal webinar. Finally, the outcome of the environmental impact assessments were reviewed by the demoplants and other partners of the SYSTEMIC project consortium.

AbstractThe strength and persistence of the tropical carbon sink hinges on the long‐term responses of woody growth to climatic variations and increasing CO2. However, the sensitivity of tropical woody growth to these environmental changes is poorly understood, leading to large uncertainties in growth predictions. Here, we used tree ring records from a Southeast Asian tropical forest to constrain ED2.2‐hydro, a terrestrial biosphere model with explicit vegetation demography. Specifically, we assessed individual‐level woody growth responses to historical climate variability and increases in atmospheric CO2 (Ca). When forced with historical Ca, ED2.2‐hydro reproduced the magnitude of increases in intercellular CO2 concentration (a major determinant of photosynthesis) estimated from tree ring carbon isotope records. In contrast, simulated growth trends were considerably larger than those obtained from tree rings, suggesting that woody biomass production efficiency (WBPE = woody biomass production:gross primary productivity) was overestimated by the model. The estimated WBPE decline under increasing Ca based on model‐data discrepancy was comparable to or stronger than (depending on tree species and size) the observed WBPE changes from a multi‐year mature‐forest CO2 fertilization experiment. In addition, we found that ED2.2‐hydro generally overestimated climatic sensitivity of woody growth, especially for late‐successional plant functional types. The model‐data discrepancy in growth sensitivity to climate was likely caused by underestimating WBPE in hot and dry years due to commonly used model assumptions on carbon use efficiency and allocation. To our knowledge, this is the first study to constrain model predictions of individual tree‐level growth sensitivity to Ca and climate against tropical tree‐ring data. Our results suggest that improving model processes related to WBPE is crucial to obtain better predictions of tropical forest responses to droughts and increasing Ca. More accurate parameterization of WBPE will likely reduce the stimulation of woody growth by Ca rise predicted by biosphere models.

Abstract To thrive in extreme conditions, organisms have evolved a diverse arsenal of adaptations that confer resilience. These species, their traits, and the mechanisms underlying them comprise a valuable resource that can be mined for numerous conceptual insights and applied objectives. One of the most dramatic adaptations to water limitation is desiccation tolerance. Understanding the mechanisms underlying desiccation tolerance has important potential implications for medicine, biotechnology, agriculture, and conservation. However, progress has been hindered by a lack of standardization across sub-disciplines, complicating the integration of data and slowing the translation of basic discoveries into practical applications. Here, we synthesize current knowledge on desiccation tolerance across evolutionary, ecological, physiological, and cellular scales to provide a roadmap for advancing desiccation tolerance research. We also address critical gaps and technical roadblocks, highlighting the need for standardized experimental practices, improved taxonomic sampling, and the development of new tools for studying biology in a dry state. We hope that this perspective can serve as a roadmap to accelerating research breakthroughs and unlocking the potential of desiccation tolerance to address global challenges related to climate change, food security, and health.

The emergence of palm oil as the world's most produced and consumed vegetable oil has prompted various policy initiatives to help govern the industry in a sustainable manner. These initiatives include transnational sustainable certification schemes, such as the Roundtable of Sustainable Palm Oil (RSPO), and national level sustainability standards, such as Malaysian Sustainable Palm Oil. To date, attempts to find consensus on sustainable policy and processes has been characterised by tension and disagreement. Most notably, stakeholders participating in policy dialogue from producing countries are unsatisfied with the outcomes of transnational palm oil governance. Tension stems from observations that sustainability is understood differently in the palm oil producing countries of the Global South compared with Northern consumption markets. To understand the different framings of palm oil and potential governance solutions, we investigate media coverage of palm oil sustainability in two different countries: the Netherlands – the largest importer of palm oil in Europe – and Malaysia – the second largest exporter of palm oil in the world after Indonesia. From a sample of 397 Malaysian and Dutch newspaper articles between 2000 and 2015, we employ framing analysis to examine the similarities and differences in media representations of palm oil sustainability. Our findings reveal considerable differences in the way palm oil sustainability is framed in the two countries. Malaysian media frame palm oil as a sustainable industry yet underpinned by a distrust towards transnational sustainability governance (e.g. RSPO) and a perception of unfair treatment towards producing countries by the West. Conversely, Dutch media frame the West as proud consumers of palm oil, who are driving up sustainability standards through NGO scrutiny and participation in transnational processes. We argue that a comparative analysis of media frames offers instructive insights for understanding processes of transnational sustainability governance. In particular, we posit that reconciling policy tensions between North and South palm oil stakeholders could be achieved by highlighting the differences in sustainability framings at different points in the value chain to identify contestation and consensus.

The vast majority of land users at the Central Plateau of Burkina Faso make a living by farming small plots, where mainly staple crops are produced for subsistence use. Both area interventions and line interventions comprising indigenous techniques as well as introduced techniques can be encountered at the Central Plateau and have proved to be effective. There is a preference for semi-permeable line measures that slow down runoff and prevent water logging in wet periods.In order to ascertain the rationale behind the choice of soil and water conservation measures and the implementation strategy, five large soil and water conservation projects in three Sahelian countries have been investigated. The choice of technology and the way of implementation differed greatly between projects. This was attributable more to the preference of donors and projects than to any physical, socio-economic and agronomic differences. On the basis of project performances, a recommendable strategy for farmers' fields appeared to be the use of the local zay technique to achieve a short-term improvement, and to combine this with stone lines or vegetation barriers for a long-term effect.Low adoption rate of soil and water conservation (SWC) measures in erosion-prone areas is often ascribed to the high investment costs of measures. The costs of these measures may seem modest in comparison to costs for infrastructure, but they are often too high for the individual subsistence farmer, especially in marginal semi-arid zones in the Sahel. Investment costs are highest for stone rows, whereby the transport of stones requires substantial inputs of labour and means of transport. Vegetation barriers are less costly, but have the disadvantage that they need to be planted in the rainy season, when agricultural production activities have the highest priority.A major reason why farmers consider the costs prohibitive relates to the uncertain nature of the benefits. These benefits comprise of several elements, some of which may have immediate effect (e.g. moisture retention), but most of which occur only gradually over a long period of time, and are hard to assess and even harder to quantify. In a qualitative multi-criteria analysis stone rows showed the best results, and this was also the measure that with the help of development projects, has been most often applied at the Central Plateau in Burkina Faso. However, vegetation barriers, which have not yet been greatly promoted come a close second and are the best solution in areas where stones are scarce or not available. This conclusion was the starting point of the water conservation research by means of vegetation barriers.The on station field experiment was set up to evaluate the effectiveness of vegetation barriers for soil and water conservation under semi-arid conditions at the research station of the Institute de Développement Rural (IDR) at Gampela.Seven local plant species (grasses: Andropogon gayanus, Vetiveria zizanioides ; woody species: Acacia nilotica, Guiera sengalensis,Piliostigma reticulatum, Ziziphus mauritiana ; and a succulent: Agave sisalana ) were planted on a 2 % slope of a sandy loam (Chromic Luvisol), in 21 plots of 20 x 20 m as conservation barriers, along the contour.To determine the runoff interception efficiency of barriers and to find out the influence of slope length and alley treatment, runoff induced by a large number of storms was measured on plots with slope lengths of 1.25 m (1 m 2), 6.25 m (5 m 2), and 12.5 m (10 m 2). Plots without a barrier (no barrier) were used as the control. Grass barriers and stone rows proved to be very effective (effective barrier) in impeding runoff and reducing runoff to only 20 % of precipitation. The runoff through woody species and succulents (less effective barrier) was about 50 % of precipitation. By comparison with the control, a barrier always resulted in water conservation. Less effective barriers with a bare or cropped alley showed a decrease in runoff percentage with an increase of plot length along the slope, whereas effective barriers with a bare or cropped alley showed an increase of runoff along the slope. The effect of crop development on runoff was rather small. Runoff reduction during the growing season was highest on plots without a barrier and on plots with the less effective barriers.On short (1.25 m) and long (12.5 m) slopes the influence of rain intensity on runoff production was marginal. On the medium slope length (6.25 m), rain intensity influenced runoff most on plots with a less effective barrier. A general conclusion was that for longer slopes, all factors such as type of barrier, land use and rain intensity became less important. In that situation, large runoff volumes exceeded the quantity of water that can be dammed by the vegetation barriers, and can be intercepted as a result of land use activities and vegetation on the alley. It is concluded that barriers improve water conservation and are most effective when closely spaced.Large differences in sediment transport in the amount of sediment yield were found between the barrier types. Grasses and natural vegetation proved to be very effective in catching soil particles and diminishing sediment transport. The dense effective barriers slow down flow velocity, build up backwater and promote sedimentation upstream. The through flow in the less effective barriers with woody species and succulents was slightly hampered and flow velocity was not reduced enough, resulting in a higher sediment transport. Under degraded conditions soil loss diminished 50 % with less effective and 70-90 % with effective barriers. During the initial cropping phase (light tillage) sediment transport was reduced 40-60 % with effective barriers and showed an increase with less effective barriers. In the full tillage (weeding) period sediment transport decreased by 80-90 % for effective and 70 % for less effective barriers. Sediment yield could be best predicted by the erosivity index, second best by runoff amount (mm) closely followed by maximum peak intensity. All these parameters were related to the volume of overland flow needed to transport soil particles.At the research site annual rain quantities seldom gave rise to a shortage of water for vegetation barriers and sorghum. Conversely, dry spells had a big influence on soil water, exhausting it sometimes during the growing season, and causing delay in plant growth. Water loss by evaporation was negligible under (effective) Andropogon and substantial under (less effective) Ziziphus barriers. Reduced evaporation and the larger effect on runoff reduction compensated the high transpiration of Andropogon. Most barriers transpired without restrictions, when water was readily available. Only Piliostigma showed to limit transpiration during the second part of the growing season.The soil water content was monitored twice a week at different measuring depths with the TDR technique at a transect perpendicular to the barriers. For the investigated alley crop system it was found that, despite the difference in effectiveness of the barriers and soil water dynamics, there were no striking differences in yield (grain and straw) between the treatments in the distinct years. However, there were big differences in crop yields between the respective years. These differences were strongly related to the amount and the distribution of the rain over the crop development stages. When water for the sorghum crop was not always readily available during the growing season, but when rain distribution and rain quantity were favourable (1999), yields were close to average on-station yields. In the dry year 1998, there was a total annual amount of rain to produce maximum yields, but a number of dry spells had a big influence. In 1998, about half of the annual water and in 1999, only about a third of the available annual water was used for crop production.Effective barriers conserved water even during dry years and compensated at least their own consumption and increased crop yields over a distance of about 6 m upstream of the barrier. Since the soil water was always enhanced close to and under the effective (Andropogon) barrier and yields did not reflect to favourable soil water conditions, ponding and shading appeared to be important growth constraints. The barrier effect of less effective Ziziphus barriers was not good during dry years and even not enough to compensate its own consumption. In dry years, water competition was responsible for yield reductions adjacent to the barrier on the less effective barrier plots. In wet years this barrier caught enough water for its own water consumption and also enough to improve crop yields a few meters upstream. Stone row barriers sometimes retained too much runoff water causing water logging. Even in dry years the barrier effect of stone rows was less good than the effective vegetation barrier. Effective vegetation barriers were slightly better than stone rows, but the difference remained small.Management actions have to be undertaken to diminish the negative impacts, like ponding or excessive water use by the barriers. During drought the barrier has to be cut back to diminish competition. During wetness, removal of some stones in the stone row and cutting a part of the effective vegetation barrier can help to drain excess water. In farmers fields it was often observed that only short rows of Andropogon were applied. Obviously their experience is that in case of drought these short barriers catch enough water and in case of abundance, the water can flow round.Runoff management is one of the tools to increase the available water for agricultural production in areas where rainfall is erratic. From the Gampela research runoff percentages can be estimated for design purposes. Water use of vegetation barriers was related to meteorological factors and soil moisture availability and found to be simple and reliable to predict transpiration.Amongst the soil and water conservation (SWC) measures adopted in the Sahel, contour vegetation barriers (CVB) constitute a cheap option in terms of labour and material requirements. In order to understand the actual adoption and maintenance of CVB, labour requirements of commonly adopted CVB species were evaluated. Labour requirements for the installation of 100 m CVB varied from 7-8 man-days when using cuttings or direct sowing to 15 man-days when installed from nursery seedlings, excluding 8 days for the installation of a dead fence. Maintenance takes 2-4 days per 100m. Phasing the installation over several years is an option to overcome labour constraints. Low labour requirements for establishment and management do not explain the rather low adoption and poor maintenance of vegetation barriers. The labour requirement for establishment of barriers at the beginning of the growing season is not a real constraint. Farmers mostly choose CVB species and planting methods with low labour requirements and prefer species with additional benefits such as thatching grass, oil for soap making and fodder and fruits.At the Central Plateau vegetation barriers can play a vital role in conserving soil and water. Well managed vegetation barriers can contribute to the re-greening of the area.

A multistage reverse electrodialysis system was studied at the REDstack research facility (the Afsluitdijk, the Netherlands) for over 30 days to describe the performance of such configuration under natural water conditions. The experiments were done with two 0.22 × 0.22 m2 stacks in series comprising 32 cell pairs (3.1 m2 of membrane area) for stage 1 and 64 cell pairs (6.2 m2 membrane area) for stage 2. The total gross power density at the available salinity gradient was stable at around 0.35 W•m􀀀 2. The total net power density, corrected for the initial pressure drop of the stacks, was 0.25 W•m􀀀 2 at an energy efficiency of 37 %. Throughout the operation, due to increased stack pressure drop, the actual total net power density lowered to 0.1 W•m􀀀 2. A distinct behaviour was found for multivalent ions in each stage. For stage 1, Ca2+ and SO42􀀀 were transported from the river water to the seawater side, so-called uphill transport. For stage 2, uphill transport was not found, in line with Donnan potential calculations. Stack autopsy revealed microorganisms with sizes ten times larger than the cartridge filter nominal pore size (5 μm) and biofilm covering part of the spacer open area, both contributing to the increasing pressure drop in the stacks. This study showed that stable gross power densities and high energy efficiencies were obtained from feeding natural waters to a multistage reverse electrodialysis system, independent of fouling. In addition, it emphasized the importance of maintaining pumping power losses low for a viable deployment of the technology.