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Adopting soil and crop management practices that conserve or enhance soil structure is critical for supporting the sustainable adaptation of agriculture to climate change, as it should help maintain agricultural production in the face of increasing drought or water excess without impairing environmental quality. In this paper, we evaluate the evidence for this assertion by synthesizing the results of 34 published meta-analyses of the effects of such practices on soil physical and hydraulic properties relevant for climate change adaptation in European agriculture. We also review an additional 127 meta-analyses that investigated synergies and trade-offs or help to explain the effects of soil and crop management in terms of the underlying processes and mechanisms. Finally, we identify how responses to alternative soil–crop management systems vary under contrasting agro-environmental conditions across Europe. This information may help practitioners and policymakers to draw context-specific conclusions concerning the efficacy of management practices as climate adaptation tools. Our synthesis demonstrates that organic soil amendments and the adoption of practices that maintain “continuous living cover” result in significant benefits for the water regulation function of soils, mostly arising from the additional carbon inputs to soil and the stimulation of biological processes. These effects are clearly related to improved soil aggregation and enhanced bio-porosity, both of which reduce surface runoff and increase infiltration. One potentially negative consequence of these systems is a reduction in soil water storage and groundwater recharge, which may be problematic in dry climates. Some important synergies are reductions in nitrate leaching to groundwater and greenhouse gas emissions for nonleguminous cover crop systems. The benefits of reducing tillage intensity appear much less clear-cut. Increases in soil bulk density due to traffic compaction are commonly reported. However, biological activity is enhanced under reduced tillage intensity, which should improve soil structure and infiltration capacity and reduce surface runoff and the losses of agro-chemicals to surface water. However, the evidence for these beneficial effects is inconclusive, while significant trade-offs include yield penalties and increases in greenhouse gas emissions and the risks of leaching of pesticides and nitrate. Our synthesis also highlights important knowledge gaps on the effects of management practices on root growth and transpiration. Thus, conclusions related to the impacts of management on the crop water supply and other water regulation functions are necessarily based on inferences derived from proxy variables. Based on these knowledge gaps, we outlined several key avenues for future research on this topic. ispartof: Soil vol:9 issue:1 pages:1-20 status: published

Context and research question Suppose that we raise the groundwater levels in certain places, thus increasing the soil moisture content. What impact would that presumably have on the yield of common agricultural crops in Flanders? This research question is addressed in the PEILIMPACT project. In order to mitigate the effects of climate change, the Flemish coalition agree- ment 2019-2024 strongly emphasizes increased resilience to drought, including through the active deployment of a resilient space with (additional) nature. Agricultural activit- ies can experience positive effects through the water being buffered in the landscape. Yet, there are also possible negative effects: if the water level is too high, this could compromise the ability to work the land, could negatively affect crop growth and in- crease disease pressure on crops, as well as the availability and leaching of nutrients to surface and groundwater. Research methodology Through targeted dialogue moments with individual farmers from different agricultural regions in Flanders, we obtain experiential knowledge about the effect of too high or too low groundwater levels on certain crops. We detect possible obstacles to their agricultural activity and important effects on yield, both positive and negative, and their causes. The model must help to determine “sufficiently favorable” groundwater levels for agriculture given a number of parameters. Simple guide values are too gener- alistic, because suitable groundwater levels for agriculture depend on the type of soil, the crop and the depth of the roots, the time of year, and so on. To determine feasible water level increases for a specific situation, model calculations for a range of different weather scenarios and for the crops grown in a specific location, is needed. In this study we determine the effect of groundwater levels in crop yield based on open data layers in Flanders. Relevance An evaluation framework for the impact of groundwater level increases can be used to calculate the effect of water management decisions and to link these to compensation for affected landowners as well as to discuss sustainable solutions with farmers and nature managers. The framework can also assist farmers in crop selection etc. on a particular field with its specific soil and meteorological context. This project was carried out by the Flemish Institute for Agricultural, Fisheries and Food Research (ILVO) [Diana Estrella, Sarah Garré, Tom De Swaef] i.s.m. KWR Water Research Institute [Ruud Bartholomeus] and Wageningen University & Research (WUR) [Martin Mulder, Mirjam Hack-ten Broeke] &nbsp

Agriculture is facing immense challenges. We have to produce enough food while safe‐guarding the environment for future generations. This results in the need to use less water and fertilizer, and to harness soil quality. Key to achieving this goal is improving the understanding of processes and interactions governing the soil–plant–atmosphere continuum of agricultural ecosystems. Geophysical tools have great potential to better characterize and quantify these processes noninvasively from the plot to landscape scale. Nevertheless, a number of challenges remain for geophysical results to be better exploited by different scientific communities and by decision‐makers. In this special section, we explore ongoing research in the relatively new field of agrogeophysics, and we provide an overview of potential applications and highlight future research needs.

Detailed knowledge of the intra-field variability of soil properties and crop characteristics is indispensable for the establishment of sustainable precision agriculture. We present an approach that combines ground-based agrogeophysical soil and aerial crop data to delineate field-specific management zones that we interpret with soil attribute measurements of texture, bulk density, and soil moisture, as well as yield and nitrate residue in the soil after potato (Solanum tuberosum L.) cultivation. To delineate the management zones, we use aerial drone-based normalized difference vegetation index (NDVI), spatial electromagnetic induction (EMI) soil scanning, and the EMI–NDVI data combination as input in a machine learning clustering technique. We tested this approach in three successive years on six agricultural fields (two per year). The field-scale EMI data included spatial soil information of the upper 0–50 cm, to approximately match the soil depth sampled for attribute measurements. The NDVI measurements over the growing season provide information on crop development. The management zones delineated from EMI data outperformed the management zones derived from NDVI in terms of spatial coherence and showed differences in properties relevant for agricultural management: texture, soil moisture deficit, yield, and nitrate residue. The combined EMI–NDVI analysis provided no extra benefit. This underpins the importance of including spatially distributed soil information in crop data interpretation, while emphasizing that high-resolution soil information is essential for variable rate applications and agronomic modeling. ispartof: Vadose Zone Journal vol:20 issue:4 pages:1539-1663 status: published

In the context of global soil degradation, biochar is being promoted as a potential solution to improve soil quality, besides its carbon sequestration potential. Burying biochar in soils is known to effect soil physical quality in the short-term (Particle density and bulk density slightly decreased as a function of charcoal content. Because particle density and bulk density were affected to a similar extent by charcoal content, total porosity was not affected by the presence of century-old charcoal. Regarding the soil water retention curve, charcoal affected mostly water content in the mesopore range. This effect was strongest for the sandy loam. On the other hand, the presence of century-old charcoal increased significantly the hydraulic conductivity at pF between 1.5 and 2 for the silt loam, while no effect of charcoal was observed for the loamy soil. The study highlights a limited effect of century-old charcoal on the pore size distribution (at constant porosity) and on the resulting soil physical properties for the range of soils and charcoal concentrations investigated here. Further research may be needed to confirm the observed trends over a wider range of soil types.