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A stocktake study, in the framework of the EJP Soil programme took place across 23 European countries to formulate recommendations for harmonising methodologies for delivering fertilisation guidelines. The stocktake revealed substantial differences in the content, format and delivery of current fertilisation guidelines across Europe. Substantial differences exist in soil test methods and how crop nutrient requirements are calculated; even between neighbouring countries, with similar soil types, cropping systems and within the same environmental zone.The general consensus among all participating countries was that harmonisation of fertilisation guidelines should be increased, in terms of shared learning in the delivery and format of fertilisation guidelines and mechanisms to adhere to environmental legislation. However, it was recognised that it would be difficult, if not impossible, to harmonise soil test data and agronomic requirements at EU-level due to differences in soil types and agro-ecosystems.Nevertheless, increased future collaboration between neighbouring countries within the same environmental zone was seen as potentially very beneficial, and would contribute to the European Green Deal vision. Particularly, advancement of precision agriculture technology, enabling greatly increased nutrient use efficiency at farm and field level through more site-specific and precise fertiliser placement, and improved rate and timing of nutrient application, could be potentially very beneficial. Shared learning in the use of earth observation technology to generate maps of soil properties, soil nutrients or crop yield variability to make interpretations and contribute to decision making tools would be a potential way of harmonising the methodologies for creating fertilisation recommendations. Country-specific methodology and a lack of harmonisation prohibits the comparison or joint analysis of internationally recognised parameters to evaluate soil nutrient interactions and crop response. While complete harmonisation should not be an end in itself, methods to improve nutrient use efficiency and minimise environmental impact, at field, farm, national and international level, should be the priority.

Soil texture and microorganisms are key drivers controlling the fate of organic matter (OM) originating from decaying plant litter, and thus the stabilization of soil organic matter (SOM). However, the understanding of the mutual interactions between microbial litter decay and soil structure formation controlled by different soil textures remains incomplete. We monitored the fate of litter-derived OM (using 13C isotopic enrichment) from decaying litter (shredded maize leaves) to microorganisms and SOM in two differently textured soils (sand and loam). The two soils were incubated with litter mixed in the top layer in microcosms for 95 days during which regular CO2 and 13CO2 measurements were conducted. After the incubation, each microcosm was divided in three to separate a top, center and bottom layer. Using a physical soil fractionation scheme, we assessed the fate of litter-derived OM to free and occluded particulate OM (POM), as well as mineral associated OM (MAOM). All SOM fractions were analysed with respect to their mass distribution, C, N, and 13C contents, and for their chemical composition using compound-specific 13C-CPMAS NMR spectroscopy. The effects of contrasting textures on the total microbial community structure were studied using phospholipid fatty acids (PLFA) and the incorporation of litter-derived C into individual PLFAs was assessed via 13C-PLFA. Lastly, scanning electron microscopy and nano scale secondary ion mass spectroscopy (NanoSIMS) analysis of free POM of both textures enabled qualitative insights directly at the biogeochemical interface of the microbial hot spot of decaying plant litter.We were able to clearly demonstrate higher contents of litter-derived OM still residing as free POM in the loamy textured soil after the 95 day-incubation, while higher contents were found in occluded and MAOM in the sandy textured soil. This indicated that the overall litter decomposition was refrained in the finer-textured soil, whereas microbial alteration and allocation of litter-derived compounds was promoted in the coarser textured soil. This was further corroborated by higher respiration and higher amounts of respired litter-derived CO2-C in the sandy soil. The PLFA analysis showed a coherent pattern between the textures, with similar community structures in all treatments and significant increases in microbial abundance in the top layers induced by litter addition. This increase was found most pronounced in fungal biomarkers, which was in line with the 13C-PLFA measurements revealing over 90% of fungal biomarkers to be of litter-origin (compared to 30-40% in the other microbial groups). The labelled PLFA profiles also confirmed the importance of fungi as a vector for litter-derived OM into deeper layers of the soil columns, with significantly higher litter-derived fungal markers also in center and bottom layers. The NanoSIMS measurements verified the high 13C enrichment in fungal hyphae and further revealed clay minerals embedded in enriched microbial-derived extracellular polymeric substances and intertwined with hyphae directly on top of the POM. Based on this comprehensive data, we highlight that regardless of the texture, plant litter in association with microbial-derived products represent a hot spot for soil structure formation by harbouring a core for aggregation and MAOM formation.

One of the primary challenges of our time is develop sustainable farming systems that can feed the world with minimal environmental impact. Some studies argue that organic farming systems are best because these have minimal impact on the environment and are positive for biodiversity. Others argue that no-tillage systems are better because such systems save energy and preserve soil structure and quality. A third group argues that conventional farming systems are best because yield per hectare is highest. However, so far, systematic comparisons of major arable production systems are rare and often it is difficult to compare the advantages and disadvantages of farming systems in a systematic way due to differences in soil/site characteristics and management. Here we present data of the Swiss Farming Systems and Tillage Experiment (FAST), a long term experiment where the main European arable production systems (organic and conventional farming, reduced tillage and no tillage, each system with different cover crop treatments) are being compared using a factorial replicated design. A multidisciplinary team of researchers from various disciplines and organizations analysed this experiment. We show the advantages and disadvantages of the various production systems and present data on plant yield, life cycle analysis, global warming potential, soil quality, plant root microbiomes and above and below ground biodiversity. Our results demonstrate that: i) plant yield was highest in the conventional systems, ii) soil biodiversity and above ground diversity tended to be higher in organic production systems, iii) soil erosion was lowest in the absence of tillage and in organic production systems, iv) the positive effects of cover crops were highest in organic production systems and increased with reduced land use intensity, v) the global warming potential of organic farming systems was lower compared to conventional systems, and vi) root and plant microbiome varied between the farming systems with the occurrence of indicator species that were specific for individual farming practices. In a next step we compared the results of this experiment with observations from a large farmers network (60 fields) in Switzerland (see abstract by Büchi et al.) where organic, conventional and conservation agriculture were compared. The results of our trial (e.g. yield and environmental performance of the different farming systems) were largely in agreement with those observed in the farmers network. Overall, our results indicate that no farming system is best and the choice of the “best” production system depends on economic, ecological and environmental priorities.

The green revolution and the intensification of arable production have made a substantial contribution to increased world food production over the last 50 years. However, intensive agricultural practices have also given rise to environmental concerns such as decreased biodiversity, impaired water quality, and degraded soil quality. Soil is the basis for food production and provides a range of ecosystem functions, mostly mediated through the soil biota. Various strategies and management practices have been suggested to preserve and improve soil functioning. These include organic farming, agricultural practices with reduced or no soil tillage (e.g. conservation agriculture), and the use of cover crops instead of longer bare fallow periods. However, how soil improving cropping systems influence a range of soil functions is still unclear.

In dieser Kohortenstudie wurden anamnestische, demographische, klinische, histologische, mikrobiologische, radiologische und therapeutische Daten von 174 Patienten, die im Zeitraum von Januar 2006 bis Juli 2014 in der Klinik und Poliklinik für Mund-Kiefer-Gesichtschirurgie der Ludwig-Maximilians-Universität aufgrund einer akuten oder chronischen unilateralen Sinusitis maxillaris behandelt wurden, retrospektiv ausgewertet. Im CT zeigte sich bei einigen Patienten auch eine bilaterale Verschattung. Dies war jedoch nicht der Behandlungsgrund. Der Einschluss von geeigneten Patienten folgte prädefinierten Kriterien. Zielsetzung der vorliegenden Arbeit war es festzustellen, welche pathologischen Prozesse (entweder anamnestisch oder simultan bestehend) mit dem Auftreten einer unilateralen Sinusitis maxillaris vergesellschaftet sind. Besonders berücksichtigt wurde die mögliche Bedeutung von dentalen Implantaten, Augmentationsverfahren sowie Mittelgesichtsoperation (Umstellungsosteotomien, Frakturen) für die Entstehung einseitiger maxillärer Sinusitiden. Die Ergebnisse dieser Studie zeigten, dass die überwiegende Mehrzahl der Fälle von unilateraler Sinusitis maxillaris in Zusammenhang mit odontogenen Pathologien standen (143 Patienten, 82%). Postoperative Wundheilungsstörungen nach dentoalveolärer Chirurgie wurden besonders oft simultan mit einer unilateralen Sinusitis maxillaris festgestellt (83 Fälle, 47%). Der Erkrankungipfel fand sich in der 5. Lebensdekade. In 9 Fällen (5%) fanden sich parallel zur unilateralen Sinusitsmaxillaris periimplantäre Entzündungen an Implantaten im Oberkieferseitenzahnbereich. Bei 18 Patienten (10%) konnte keine signifikante gleichzeitig bestehende möglich Ursache für die einseitige Sinusitis maxillaris festgestellt werden. Allerdings zeigte die Anamnese all dieser Patienten stattgehabte operative Eingriffe im Bereich des Mittelgesichts (Le Fort I Osteotomie, Frakturversorgung, Lippen - Kiefer - Gaumenspaltchirurgie). Bei 8 Patienten bestätigte sich eine Medikamenten - assoziierte Kieferosteonekrose nach histologischer Untersuchung als möglicher ursächlicher Faktor der unilateralen Sinusitis maxillaris. In 2 Fällen war die Ursache für die einseitige Kieferhöhlenentzündung ein Malignom. Die Ergebnisse der vorliegenden Arbeit sind als Erhebung aus einer Mund- Kiefer - Gesichtschirugischen Klinik nicht unbedingt auf die Gesamtpopulation übertragbar. Allerdings wird in der Gesamtliteratur die Bedeutung odontogener Pathologie in der Entstehung der unilateralen Sinusitis maxillaris bestätigt. Iatrogene Ursachen (augmentative Chirurgie, dentale Implantologie, operative Eingriffe im Bereich des Mittelgesichts) scheinen eine Rolle in der Ätiologie der unilateralen Sinusitis maxillaris spielen zu können. Als seltene Diffentialdiagnose einseitiger Sinusitiden sollten Medikamenten - assoziierte Kiefernekrosen und Malignome bedacht werden. Eine histologische Sicherung der klinischen Verdachtsdiagnose sollte folglich bei ausbleibender Besserung der Beschwerden angestrebt werden.

Below ground carbon (BGC) inputs to soil, i.e. root biomass and rhizodeposition carbon (C), are among the most important variables driving soil C dynamics in agroecosystems. Hence, increasing BGC inputs to deep soil is a proposed strategy to sequester C in the long term. As BGC inputs are inherently difficult to measure in the field, they are usually estimated from yield in order to supply soil C models with input data. While fertilization intensity considerably affects above ground biomass, its influence on BGC inputs is largely unclear, especially with respect to the subsoil. Therefore, we determined net root biomass and rhizodeposition C of field-grown maize and wheat at harvest in different farming systems (bio-organic, conventional) and fertilization treatments (zero, manure, mineral) along an intensity gradient in two Swiss long-term field trials. Plants in microplots were repeatedly pulse-labelled with 13C-CO2 throughout the growing seasons and shoots, roots, and soil to 0.75 m depth were sampled at harvest. Despite a strong increase of above ground biomass with increasing fertilization intensity, BGC inputs were similar among treatments on both sites irrespective of soil depth. However, the proportions of rhizodeposition C of BGC inputs averaged 54 to 63% and were, therefore, much larger than the widely adopted 40% for field-grown cereals. They increased with soil depth and were highest under sole organic fertilization. The shift in whole-plant C allocation towards above ground biomass with increasing fertilization intensity entailed 10% higher C allocation below ground in organic than conventional farming for both maize and wheat. Our findings imply that yield-independent values provide closer estimates for BGC inputs to soil of cereals in different farming systems than yield-based functions. We further conclude that fertilization has only little potential to alter absolute amounts of BGC inputs to deep soil in order to sequester C in the long term.

Root biomass is the most commonly studied root parameter to investigate below ground crop response to environmental conditions and carbon cycling in agroecosystems. Root growth is strongly regulated by site-specific growth conditions and resource availability, but only little is known about the extent to which root biomass, vertical distribution, and size class respond to fertilization intensity as compared to site. We determined coarse (> 2 mm) and fine (> 0.5 mm and ≤2 mm) root biomass of maize and wheat in three soil layers to 0.75 m depth in different farming systems (half and full organic, full conventional) and fertilization treatments (zero, manure, full mineral N plus half mineral PK, full mineral NPK) of the Swiss long-term field trials DOK and ZOFE, respectively, and evaluated the effects of fertilization intensity and site on root biomass, vertical distribution, and size class. In DOK, total root biomass was similar in organic and conventional farming systems. In ZOFE, wheat root biomass was 1.7-times higher under full mineral N plus half mineral PK fertilization than under zero or manure fertilization and intermediate under full NPK fertilization. Vertical root distribution and size class were only marginally affected by fertilization intensity on both sites. By contrast, total root biomass of maize and topsoil root biomass of both maize and wheat were higher but subsoil root biomass of wheat and fine root proportions of both maize and wheat were lower in DOK than in ZOFE. We conclude that roots respond more to site than to fertilization intensity and that absolute inputs of root biomass carbon to soil are similar in low- and high-intensity systems. Further, root-shoot ratios were inversely related to fertilization intensity, implying that estimations of below ground carbon inputs to soil from shoot biomass need to be differentiated by fertilization intensity. Deep (below 0.5 m) root biomass was 3-times higher for wheat than for maize, suggesting that crop choice is more important than fertilization intensity for carbon sequestration in deep soil.

Soils store significant amounts of carbon (C) and thus can play a critical role for mitigating climate change. Crop roots represent the main C source in agricultural soils and are particularly important for long-term C storage in agroecosystems. To evaluate the potential of different farming systems to contribute to soil C sequestration and thus climate change mitigation, it is of great importance to gain a better understanding of the factors influencing root C allocation and distribution. So far, it is still unclear how root C allocation varies among farming systems and whether the choice of management practices can help to enhance root C inputs. In this study, we compared root C allocation in three main arable farming systems, namely organic, no-till, and conventional farming. We assessed root biomass, vertical root distribution to 0.75 m soil depth, and root-shoot ratios in 24 winter wheat fields. We further evaluated the relative importance of the farming system compared to site conditions and quantified the contribution of individual management practices and pedoclimatic drivers. Farming system explained one third of the variation in topsoil root biomass and root-shoot ratios, both being strongly positively related to weed biomass and soil organic C content and negatively to mineral nitrogen fertilization intensity. Root C allocation was significantly higher in organic farming as illustrated by an increase in root biomass (+40%) and root-shoot ratios (+60%) compared to conventional farming. By contrast, the overall impact of no-till was low. The importance of pedoclimatic conditions increased substantially with soil depth and deep root biomass was largely controlled by precipitation and soil texture, while the impact of management was close to zero. Our findings highlight the potential of organic farming in promoting root C inputs to topsoils and thereby contributing to soil organic matter build-up and improved soil quality in agroecosystems.

Root biomass is one of the most relevant root parameters for studies of plant response to environmental change, soil carbon modelling or estimations of soil carbon sequestration. A major source of error in root biomass quantification of agricultural crops in the field is the presence of extraneous organic matter in soil: dead roots from previous crops, weed roots, incorporated above ground plant residues and organic soil amendments, or remnants of soil fauna. Using the isotopic difference between recent maize root biomass and predominantly C3-derived extraneous organic matter, we determined the proportions of maize root biomass carbon of total carbon in root samples from the Swiss long-term field trial “DOK”. We additionally evaluated the effects of agricultural management (bio-organic and conventional), sampling depth (0 - 0.25, 0.25 - 0.5, 0.5 - 0.75 m) and position (within and between maize rows), and root size class (coarse and fine roots) as defined by sieve mesh size (2 and 0.5 mm) on those proportions, and quantified the success rate of manual exclusion of extraneous organic matter from root samples. Only 60 % of the root mass that we retrieved from field soil cores was actual maize root biomass from the current season. While the proportions of maize root biomass carbon were not affected by agricultural management, they increased consistently with soil depth, were higher within than between maize rows, and were higher in coarse (> 2 mm) than in fine (≤ 2 mm and > 0.5) root samples. The success rate of manual exclusion of extraneous organic matter from root samples was related to agricultural management and, at best, about 60 %. We assume that the composition of extraneous organic matter is strongly influenced by agricultural management and soil depth and governs the effect sizes of the investigated factors. Extraneous organic matter may result in severe overestimation of recovered root biomass and has, therefore, large implications for soil carbon modelling and estimations of the climate change mitigation potential of soils.