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Realization of the objectives set out by the EU for growth in organic agriculture will require a host of initiatives. It is evident that more nutrients, which are safe, will be required, and the inputs utilized will need to be broadly socially accepted. The recycling of societal waste in organic agriculture is an opportunity to supply large amounts of carbon and nutrients to support the growth of the sector. However, this opportunity intersects with a dilemma of whether the use of recycled waste products in organic agriculture ultimately might weaken the credibility of organic farming from a consumer perspective. Furthermore, due to the nature of organic waste products, concerns are raised about human and environmental health impacts. Whilst the recycling of wastes adheres to the organic principle 1 of ecology, being based on ecological systems and cycles, the notion of utilizing currently unused organic societal waste is challenged by the principle of care and health. The ReConCile (Recycling, Consumer Credibility and Ecosystem integrity) research project focused on two key topics, namely environmental safety, and social acceptability from a consumer perspective. The project focused on exploring questions which can facilitate the pathway towards increased utilization of potential sources of nutrients from societal waste in organic agriculture, and which are currently not utilized or utilized under strict guidelines. The scientific problem, which ReConcile addressed was: Can recycling from society to organic agriculture be developed in line with organic principles of ecology, health and care, while balancing consumer acceptability? ReConCile is a Danish project supported by a grant from the GUDP programme under the Ministry of Food, Agriculture and Fisheries of Denmark, as part of the Organic Research, Development and Demonstration (RDD)-5 programme (RECONCILE; grant no. 34009-191557) and financially supported by Organic Denmark and SEGES Innovation through a collabor

Bio-based fertilizers (BBFs) are an increasingly important source of nutrients in agriculture, promoted by the new EU fertilizer regulation aiming to enable a circular bioeconomy. Predicting the mineralization-dependent nutrient release of BBFs is critical for their appropriate use and to minimize environmental losses. We assessed mineralizable nitrogen (N) and carbon (C) of a representative selection of 32 BBFs and evaluated a set of chemical extraction methods to predict their N mineralization dynamics. In 84-day aerobic incubations, cumulative mineral N release varied between 13 and 100 % of amended N. Mineralized C ranged from 10 % to 117 % of amended C. Based on the dynamics of N and C mineralization, BBFs were classified into five significantly different groups. Among the tested chemical indicators of N mineralization from BBFs, cold and hot water presented the lowest extraction intensities, followed by hot potassium chloride and hot sulfuric acid extractions, while C:N ratio is based on total contents. Mineral N released almost immediately was best predicted by cold water extractable N, while hot sulfuric acid extractable N and C:N ratio predicted N released after the first two weeks and after 84 days, respectively. The combination of these three indicators was able to discriminate BBFs into four out of five mineralization classes. Such a cost-effective yet accurate estimation of N mineralization dynamics from BBFs can therefore be used as a basis to inform farmers on suitable timing and amount of BBF application, improving the synchrony between N release from BBFs and crop N demand.

Agriculture provides food to a still growing population but is a major driver of the acceleration of global nutrient flows, climate change, and biodiversity loss. Policies such as the European Farm2Fork strategy aim to mitigate the environmental impact of land-use by fostering organic farming. To assess long-term environmental impact of organic food production we synthesized more than four decades of research on agronomic and environmental performance of the oldest system comparison experiment on organic and conventional cropping systems (DOK experiment). Two organic systems (bioorganic and biodynamic) are compared with two conventional (manure-based integrated and mineral-based) systems all with the same arable crop rotation including grass-clover, and manure from livestock integrated in all except the mineral-based system. Organic systems used 92% less pesticides and 76% less mineral nitrogen than conventional systems. Nitrogen use efficiency, that also considers biological nitrogen fixation, was above 85% for all systems. Organic fertilization with farmyard manure maintained or increased soil carbon and nitrogen stocks in the long term, especially in the biodynamic system with manure compost. Conventional mineral-based cropping reduced soil organic carbon and nitrogen stocks. Higher soil organic carbon stocks in organic cropping did not translate to increased N2O emissions, which were the main driver for 56% lower soil-based, area-scaled climate impact compared to the integrated conventional system with manure. Organic cropping systems, especially compost-based biodynamic, showed enhanced soil health, richness of micro- and macrofauna and weed species. Highest yields were achieved in integrated conventional system, with highest total nitrogen inputs and enhanced soil health compared to pure mineral fertilization. Yet, these benefits come at the cost of lower nitrogen use efficiency and higher N2O emissions. Despite a rigorous reduction of inputs yields of the org

Recycling phosphorus (P) from waste streams like sewage sludge, animal manures or food industry by-products is required to sustain soil fertility without depleting non-renewable P resources. Several technologies are available for P recovery, leading to fertilizers differing in P solubility and bioavailability. In this study, thirty fertilizers obtained through different technologies were tested to assess if their fertilization efficiency was equivalent to mineral soluble fertilizer applied as triple superphosphate (TSP). The main selection criteria were (1) ensuring a wide chemical diversity, and (2) choosing products already on the market or at a late stage of development, to encompass a representative selection of current and future recycled fertilizers. The products were classified according to their organic carbon content and neutral ammonium citrate (NAC), and the main P species of each fertilizer was determined through K-edge and L2,3-edge X-ray absorption near edge structure spectroscopy (XANES). Three pot experiments with wheat, barley and ryegrass were conducted in three growing substrates with contrasting properties, all within a pH range of 5.8–6.9. Fertilizers containing ammonium magnesium phosphate, monoammonium phosphate, monocalcium phosphate, and dicalcium phosphate type species as dominant P species showed a similar fertilization efficiency to TSP, while fertilizers with hydroxyapatite, tricalcium phosphate, phytic acid or iron phosphates as their main P species had lower fertilization efficiencies. We conclude that while the trend towards high-efficiency, refined inorganic recycled P fertilizers is positive, lower-performing, mostly unrefined fertilizers must be assessed in light of their long-term P supply potential and additional benefits to soil health owing to their content of organic matter and other nutrients.

In dem Dossier werden die Ergebnisse aus 45- Jahren Forschung im Langzeitversuch kurz und verständlich zusammengefasst. Es richtet sich an interessierte Fachleute aus der Praxis, Beratung und Wissenschaft. Im DOK-Versuch werden die landwirtschaftlichen Anbausysteme Biologisch-dynamisch, Biologisch-organisch und Konventionell miteinander verglichen. Das Dossier stellt Ergebnisse aus den Bereichen Ertrag, Bodenqualität, Nährstoffversorgung, Biodiversität und Klima vor.

The dossier summarises the results of 45 years of long-term research in a concise and comprehensible manner. It is aimed at interested experts from practice, advisory services and science. The DOK trial compares biodynamic, organic and conventional farming systems. The dossier presents results from the areas of yield, soil quality, nutrient supply, biodiversity and climate.

Ce dossier résume brièvement et de manière compréhensible les résultats de 45 années de recherche dans l’essais à long terme DOC. La publication s'adresse aux producteurs et productrices, conseillères et conseillers et aux scientifiques intéressés. Dans l'essai DOC, les systèmes de culture agricole biodynamique, biologique-organique et conventionnel sont comparés entre eux. Le dossier présente des résultats sur les rendements, la qualité des sols, l'approvisionnement en nutriments, la biodiversité et le climat.

Les résultats actualisés de l’essai DOC approfondissent ceux tirés de plus de 45 ans de recherches permanentes.

I risultati aggiornati dell'esperimento DOK approfondiscono le conoscenze di oltre 45 anni di ricerca costante.

Über 45 Jahre hinweg hat sich der DOK-Versuch zu einer treibenden Kraft des Biolandbaus entwickelt. Welche Richtung nimmt der Versuch in Zukunft?

L’essai DOC s’est développé pendant plus de 45 ans comme force motrice de l’agriculture biologique. Quelle direction cet essai prendra-t-il à l’avenir?

Aktualisierte Ergebnisse des DOKVersuchs vertiefen die Erkenntnisse aus über 45 Jahre andauernder Forschung.

Sull’arco di oltre 45 anni l’esperimento DOK si è evoluto a forza trainante dell’agricoltura biologica. Quale direzione seguirà in futuro?

Die Broschüre besteht aus verschiedenen Perspektiven aus Theorie und Praxis auf das Thema Mykorrhiza und ist in unterschiedlichen Themenbereichen untergliedert. Die wissenschaftlichen Studien der Autor*innen wurden zusammengefasst, die Quellenangabe der Gesamtwerke befindet sich jeweils unter dem Haupttitel. Alle interessierten Leser*innen sollen ermuntert werden, diese Broschüre zur selbsttätigen und kritisch offenen Auseinandersetzung zu betrachten.

Vor nicht allzu langer Zeit galt Pflanzenkohle lediglich als Nebenprodukt der Holzverarbeitung. Doch heute ist sie ein Schlüsselelement in der Diskussion um nachhaltige Landwirtschaft und Klimaschutz. In den letzten Jahren hat die Popularität von Pflanzenkohle zur Bodenverbesserung und als CO2-Speicher stark zugenommen. In unserer aktuellen Podcast-Episode beleuchten wir ihre vielfältigen Anwendungsmöglichkeiten und die bisher gewonnenen wissenschaftlichen Erkenntnisse.

Inhalt - Anfänge der konservierenden Bodenbearbeitung, - Bodenbearbeitungssysteme - Klimawandel Schutz und Anpassung im Ackerbau - Humusumlagerung durch die reduzierte Bodenbearbeitung - Humusvorräte Schweiz: Anbausysteme und Bodenbearbeitung im Vergleich - Bodenbearbeitung - Langfristige Auswirkungen - Flächenrotte und Lachgas - Fazit Klimaschutz - Bodenaggregate - Verbesserte Bodenstruktur an der Oberfläche - Achtung Bodendichte bei Umstellung auf Reduziert! - Fazit Klimaanpassung - Strategische Bodenbearbeitung

The study examines the performance of different organic phosphate and nitrogen fertilisation methods in organic farming.

The study examines the effects of different fertilisation methods on greenhouse gas emissions in organic farming.

Norsk Fjordhestsenter må innføre nye løsninger for gjødselhåndtering. De har et ønske om å finne løsninger som er bærekraftige og fremtidsrettet, både økonomisk og miljømessig. I dette forprosjektet ble det lagt vekt på å utrede løsninger der hestemøkk kan tilbakeføres til landbruket. I rapporten er noen håndteringsalternativer skissert og i tillegg noen eksempler fra andre staller. Type og mengde strø har innvirkning på hestemøkkens kvalitet for bruk som gjødsel, jordforbedrer eller materiale i kompost. Det ble utført en test ved fjordhestsenteret for å undersøke om gummimatter i hesteboksene ville føre til redusert bruk av flis. Resultatet var at gummimattene heller økte bruken. Medisinrester i hestemøkk kan føre til kvalitetsforringelse av gjødsel- eller kompostprodukter og i visse tilfeller være en risiko for miljøet. Det ble utført en kartlegging av medisinbruken ved senteret som et grunnlag for fremtidig vurdering av gjødselpraksis. I prosjektet ble det lagt vekt på involvering av ulike brukergrupper og målgrupper i pågående prosess med å utrede nye løsninger for håndtering av hestemøkk. Det ble arrangert en workshop og et seminar for å bevisstgjøre om hestemøkkens verdi og for å få innspill om aktuelle løsninger for framtidig gjødselhåndtering ved fjordhestsenteret.

Effluent water and mechanically filtered sludge from recirculating aquaculture systems (RAS) contain significant concentrations of nitrogen (N) and phosphorus (P) and may be applied directly as fertiliser, e.g. in hydroponic systems. However, where this is not possible the nutrients must be removed and should ideally be applied as fertiliser elsewhere, but this often involves costly transportation. To increase the amount of nutrients per kg of material to be transported, e.g. to agricultural fields, the sludge may be filtered using various methods. Chemical coagulants and flocculants are commonly applied to aid particle and nutrient removal. This report describes initial trials with fish sludge amended with the natural polymers lignocellulose and purified cellulose as filter materials, conducted at Denmark Technical University (DTU) Hirtshals, and further testing of the filer cakes as substrates for composting conducted at NORSØK, Tingvoll. The optimal composition of lignocellulose and cellulose to be used for filtration of fish sludge was determined by filtering 1 L of sludge at 4.85 g TCOD/L (total chemical oxygen demand) with combinations of lignocellulose (20, 25, 30, 35 g/L) and cellulose (0.5, 0.75, 1, 2 g/L). A minimum ratio of 0.75 g of cellulose to 35 g of lignocellulose per L of sludge was required for filtration. This combination could produce a filter cake with a dry matter content of 24 - 29%, containing most of the nutrients (N, P). The weight of material containing N and P was reduced by more than 80% by the filtration. Two types of filter cake were produced at DTU Hirtshals with these natural polymers, with and without aluminium coagulant. The cakes were frozen and transported to the Norwegian Centre for Organic Agriculture, Tingvoll where they were amended with fish meal to make batches with a C/N ratio of 55, 30, and 20. The thermophilic decomposition and CO2 respiration of these batches were studied in Dewar flasks. The mixtures without chemical c

There is a need to find novel sources of fertilizers to meet the increasing food demands of a growing human population and alternatives to mined and synthetic fertilizers for the certified organic sector. Marine residues contain all (micro-)macro-nutrients that plants need. Composting is a common method for processing organic residues for use in horticulture. To that end, a small-scale composting experiment was conducted in Dewar flasks with five marine residues mixed in six combinations: dried and ground rockweed (Ascophyllum nodosum), algae fiber from chemically processed rockweed, ground fish bones and fishmeal from cod (Gadus morhua), and ground blue mussels (Mytilus edulis). Physicochemical analyses were run on the residues and their mixtures before and after composting, with the temperature monitored over 92 days. The goal was to assess whether these residues were suitable for aerobic composting, based on tem-perature profiles and changes in physiochemical parameters, and to evaluate the final composts as potential fertilizers. The combination of algae fiber and fishmeal generated the highest heat and exhibited the greatest reduction in volume. None of the finished composts, however, were sufficiently balanced for use as fertilizers alone, but they could provide valuable organic matter and nutrients in combination with other nutrient sources.

Biostimulants (Bio-effectors, BEs) comprise plant growth-promoting microorganisms and active natural substances that promote plant nutrient-acquisition, stress resilience, growth, crop quality and yield. Unfortunately, the effectiveness of BEs, particularly under field conditions, appears highly variable and poorly quantified. Using random model meta-analyses tools, we summarize the effects of 107 BE treatments on the performance of major crops, mainly conducted within the EU-funded project BIOFECTOR with a focus on phosphorus (P) nutrition, over five years. Our analyses comprised 94 controlled pot and 47 field experiments under different geoclimatic conditions, with variable stress levels across European countries and Israel. The results show an average growth/yield increase by 9.3% (n=945), with substantial differences between crops (tomato > maize > wheat) and growth conditions (controlled nursery + field (Seed germination and nursery under controlled conditions and young plants transplanted to the field) > controlled > field). Average crop growth responses were independent of BE type, P fertilizer type, soil pH and plant-available soil P (water-P, Olsen-P or Calcium acetate lactate-P). BE effectiveness profited from manure and other organic fertilizers, increasing soil pH and presence of abiotic stresses (cold, drought/heat or salinity). Systematic meta-studies based on published literature commonly face the inherent problem of publication bias where the most suspected form is the selective publication of statistically significant results. In this meta-analysis, however, the results obtained from all experiments within the project are included. Therefore, it is free of publication bias. In contrast to reviews of published literature, our unique study design is based on a common standardized protocol which applies to all experiments conducted within the project to reduce sources of variability. Based on data of crop growth, yield and P acquisition, we conclude th

Cover crops can contribute to climate change mitigation by promoting soil organic carbon sequestration, retaining nitrogen (N) in soil and lower greenhouse gas emissions from reduced fertilization of following crops. Their N fertilizer replacement value (NFRV) varies based on cover crop type and management. This study aimed at identifying factors affecting cover crop NFRV as a means to guide N fertilizers reduction. Ryegrass (Lolium perenne L.; RG), plantain Plantago lanceolata L.; PL), red clover (Trifolium pratense L.; RC), and two mixtures (RG+PL and RG+PL+RC) were sown in May 2020 and 2021 and terminated by rotovation followed by deeper ploughing or directly by ploughing. Spring barley (Hordeum vulgaris L.) was used as a test crop to quantify NFRV. Before sowing spring barley, cover crop plots were not fertilized and control plots received 0, 50 and 100 kg mineral N ha−1. In both years, RG+PL+RC had the greatest aboveground biomass and N yield in autumn (5.5 Mg ha−1, 128 kg N ha−1), while RG had the lowest (0.7 Mg ha−1, 21 kg N ha−1). Before termination, differences between cover crop types were less pronounced in spring with no effect of termination method on NFRV. However, the NFRV was significantly correlated to cover crop biomass (p<0.001) in autumn (r=0.83) and spring (r=0.66). NFRV was as high as 100 kg N ha−1 with RC and RG+PL+RC, while negative values were obtained with autumn biomass below 1 Mg ha−1. We found a strong correlation between cover crop biomass and NFRV, which can guide N fertilization reduction if autumn cover crop biomass can be estimated. The 1 Mg ha−1 threshold confirms the need for a minimum cover crop biomass for providing desired ecosystem services.

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.

With the application, you can create gross impact balances for main nutrients (N, P, K, S, Ca, Mg) and trace nutrients (Fe, Mn, Cu, Zn, Mo, B, Na), Calculate the N-fixation performance of legumes depending on the location and management and determine humus balances. You can find detailed instructions for the calculation tool in the user manual provided on the KTBL website via the link.

Une étude du FiBL montre comment les mycorhizes augmentent les rendements en respectant l’environnement.

The EU aims to expand organic farming to 25%, yet the sector faces constraints in nutrient availability, particularly phosphorus and nitrogen. Societal waste, such as household compost and sewage sludge, contains valuable nutrients for organic farming but requires assessment for nitrogen availability, carbon storage, and contamination risks (e.g., heavy metals). Existing field trials often lack organic management practices, hindering accurate evaluation. To address this gap, a 100-year scenario analysis using the DAISY soil-plant-atmosphere model assessed four crop rotations with varying reliance on legumes, applying different nitrogen rates from various waste sources (household waste compost, sewage sludge, stored human urine) and controls (cattle manure, slurry, deep litter, and mineral fertilization). The model was validated using results from the CRUCIAL trial (Magid et al., 2006). Short term nitrogen recovery rates ranged from 50-60%, increasing to 60-70% in the long term. Deep litter, cattle manure, and compost had the lowest values followed by sewage sludge, human urine, cattle slurry, and mineral fertilization. Nitrogen losses accounted for 34-40% of applied nitrogen, following the same pattern. The opposite trend was seen for the carbon sequestration factor (compost=0.39, manure and deep litter=0.12, sewage sludge=0.09, slurry=0.02). Compost and sewage sludge resulted in surplus Cd and Cu, while Zn levels also increased for the animal manures. Yet, levels remained below EU thresholds after 100 years of continuous application. The study underscores the suitability of societal waste for organic farming, emphasizing the trade-off between nitrogen fertilizer value and carbon storage.

Anaerobic digestion of animal manures reduces methane emissions during storage while generating energy, benefiting the greenhouse gas footprint. This study presents an innovative digestate treatment approach to enhance the overall nitrogen fertilizer value, increase biomass quantity, and diversify digestate-derived fertilizers for different purposes. Cattle manure was co-digested with grass clover silage to augment total biomass volume, nitrogen availability on farm, and biogas yield. The digestates were separated via a screw press, the solid fraction underwent drying for storage stability and ammonia was stripped. A newly designed desulfurizing bio-filter based on liquid digestate input to remove sulphur from biogas, creating in an acidic liquid rich in sulphur. This liquid was enriched with ammonia from simulated stripping resulting in a sulphur-nitrogen-rich fertilizer product (LiqNS). The fertilizer value of resulting digestate products and untreated cattle slurry were evaluated in two-year field trials by injection to spring barley. Cattle slurry, anaerobic digestates, liquid digestate, and LiqNS exhibited high nitrogen fertilizer replacement values (NFRV) of 80-90% relative to mineral nitrogen, with no significant difference amongst them. Liquid digestates showed consistent performance over the years and a higher N/P ratio. Conversely, the dried fibre fraction (DF) demonstrated negative NFRV due to nitrogen immobilization. However, as a soil amendment in a nitrogen-independent crop like faba bean, DF balanced P and K uptake without yield reduction. Overall, this novel approach increased fertilizer quantity while maintaining NFRV through co-digestion, offering diverse fertilizer products to meet various agricultural needs. LiqNS emerged as a promising additional fertilizer from biogas production.

The impacts of climate change, such as drought, can affect soil microbial communities. These communities are crucial for soil functioning and crop production. Organic and conventional cropping systems promote distinct soil microbiomes and soil organic carbon contents, which might maintain different capacities to mitigate drought effects on cropping systems. A field-scale drought simulation was performed in long-term organically and conventionally managed cropping systems differing in fertilization and pesticide application. The soil microbiome was assessed during and after drought in bulk soil, rhizosphere, and roots of wheat. We found that drought shifted microbial community structures, affecting fungi more strongly than prokaryotes. Microbial communities associated with crops (i.e. rhizosphere and root) were more strongly influenced by drought compared to bulk soil communities. A drought legacy effect was observed in the bulk soil after harvesting and rewetting. The resistance and resilience of the soil microbiome to severe drought did not significantly differ across the organic and conventional cropping systems, although few individual genera (e.g. Streptomyces, Rhizophagus, Actinomadura, and Aneurinibacillus) showed system-specific drought responses. All cropping systems showed relative increases in potential plant growth-promoting genera under drought. This agricultural field study indicated that fungal communities might be less resistant to drought than prokaryotic communities in cropping systems and these effects get more pronounced in closer association with plants. Organic fertilization or the reduction in pesticide application might not have the ability to buffer severe drought stress and additional farming practices might have to be incorporated to improve drought tolerance in cropping systems.

Das Merkblatt erläutert die Grundlagen der Humuswirtschaft, stellt die wichtigsten Massnahmen vor und gibt Hinweise für die Planung einer betriebsspezifischen Strategie.

Organic and conventional cropping systems differ in type and amount of nitrogen (N) inputs. In organic cropping only organic fertilizers are permitted, while both organic and mineral fertilizers are used in conventional cropping. Fertilizer type and amount can affect N use efficiency of a cropping system, but contributions via symbiotic N fixation and changes in soil N stocks are rarely quantified based on field data when computing nutrient budgets. We calculated an N budget that accounts for these contributions based on annual data records for a period of 35 years at the Swiss DOK (bio-Dynamic, bio-Organic, Konventionell) field experiment. Here, different organic and conventional cropping systems have been maintained at two fertilization levels: typical for the respective system, and half these doses (low). Controls comprise a conventional treatment receiving solely mineral fertilizers and an unfertilized treatment. At the typical level, average fertilizer N inputs were 93 (bio-dynamic), 96 (bio-organic), and 171 (conventional system) kg N ha−1 yr−1. Nitrogen output via harvested products regularly exceeded N input with fertilizers in all treatments. In each of the 7-year crop rotation periods, legumes (grass-clover ley, intercrops, soybean) were grown in three years. Their symbiotic N fixation was quantified based on 15N studies and legume N yield data. It ranged from 75 to 122 kg N ha−1 per year of the DOK experiment, was slightly reduced under low fertilization and was the main N input for most treatments. Soil surface budgets (sum of N inputs from fertilization, symbiotic fixation, seeds, and deposition minus N outputs via crop harvests) yielded balances from −31 kg N ha−1 yr−1 (in non-fertilized control) to +46 kg N ha−1 yr−1 (conventional system with typical fertilization level). Nitrogen use efficiencies (NUE; N output with harvests as % of sum of N inputs) reached values >100 % in treatments with negative balances while NUE ranged from 85 % to 99 % in treat

Für die Nahrungsmittelproduktion ist ein gesunder Boden elementar. Der Vortrag behandelt das Potential, Limitationen und Alternativen eienr mikrobiellen Inokulation.

The case study investigated the impact of different cover crops and tillage strategies on nitrous oxide (N2O) emissions in agricultural soils. Four cover crops were studied: perennial ryegrass (RG), plantain (PL), a combination of RG and PL (RG-PL), and a mix of RG, PL, and red clover (RG-PL-RC). These cover crops were terminated either by shallow rotovation followed by deeper ploughing (ro+plou) or directly by ploughing (plou). N2O flux was continuously measured using automated chambers from March to June 2021. The study found that cumulative N2O-N emissions were generally higher for plou compared to ro+plou, with 2-to-5-fold higher emissions observed in plou for RG-PL, RG, and PL, and the smallest difference in emissions observed for RG-PL-RC. In ro+plou, the lowest and highest cumulative N2O emissions were observed in PL and RG-PL, respectively, while in plou it was RG-PL-RC and RG-PL, respectively. The average soil nitrate (NO3-N) levels increased initially, indicating mineralization and nitrification of residue-N, but gradually decreased thereafter. This decrease in NO3-N levels corresponded with an increase in N2O emissions, suggesting denitrification as the main process of N2O production.

Effective soil organic matter (SOM) management is crucial for long-term soil fertility. Humus balances are simple tools to evaluate SOM development based on applied farming practices. Here, humus balances were used to assess the effect of farm management on soil structural quality (SSQ), as well as SOM and nutrients contents. 3 groups were identified based on the farm practices used in the humus balance calculations (residue management, organic inputs, presence of intercrops as well as the ratio of legumes and leys in the crop rotation). The group interpreted as animal husbandry farms showed significantly higher SSQ, SOM and nutrient contents. Opposingly, the group interpreted as stockless farms showed the lowest SSQ, SOM and nutrient contents, potentially risking nutrient deficiencies and soil degradation. This study revealed significant effects of farm management on SSQ, nutrient and SOM contents. It showed that humus balances can be used to compare farms based on few farming practices and evaluate their effect on nutrient dynamics.

The fertiliser value of cattle slurry and digested manures was compared in parallel field experiments with organic and conventional management

Use of nutrients recycled from societal waste streams in agriculture is part of the circular economy, and in line with organic farming principles. Nevertheless, diverse contaminants in waste streams create doubts among organic farmers about potential risks for soil health. Here, we gather the current knowledge on contaminant levels in waste streams and recycled nutrient sources, and discuss associated risks. For potentially toxic elements (PTEs), the input of zinc (Zn) and copper (Cu) from mineral feed supplements remains of concern, while concentrations of PTEs in many waste streams have decreased substantially in Europe. The same applies to organic contaminants, although new chemical groups such as flame retardants are of emerging concern and globally contamination levels differ strongly. Compared to inorganic fertilizers, application of organic fertilizers derived from human or animal feces is associated with an increased risk for environmental dissemination of antibiotic resistance. The risk depends on the quality of the organic fertilizers, which varies between geographical regions, but farmland application of sewage sludge appears to be a safe practice as shown by some studies (e.g. from Sweden). Microplastic concentrations in agricultural soils show a wide spread and our understanding of its toxicity is limited, hampering a sound risk assessment. Methods for assessing public health risks for organic contaminants must include emerging contaminants and potential interactions of multiple compounds. Evidence from long-term field experiments suggests that soils may be more resilient and capable to degrade or stabilize pollutants than often assumed. In view of the need to source nutrients for expanding areas under organic farming, we discuss inputs originating from conventional farms vs. non-agricultural (i.e. societal) inputs. Closing nutrient cycles between agriculture and society is feasible in many cases, without being compromised by contaminants, and should be

This report summarizes the presentations and activities made during a workshop organized under the auspices of the project MARIGREEN_TECB (Training, Exchange, and Capacity Building), which was funded by the third supplementary call of the ERA-NET Cofund on Blue Bioeconomy (BlueBio) program (grant number 346849) . MARIGREEN_TECB was an extension of MARIGREEN (sustainable exploitation of MARINE resources to promote GREEN plant production in Europe), a project funded by the first supplementary call of the ERA-NET BlueBio program (EU Horizon 2020 grant agreement 817992). MARIGREEN's aim is to valorise poorly utilized residual materials from the blue sector by treating them with suitable technologies such as extraction, composting and biochar impregnation after extraction, and using them in organic agriculture. The project works with available residual material from fishing, the brown algae industry, the mussel industry and organic aquaculture. The main objective of MARIGREEN_TECB was to improve the understanding of humification during composting of marine raw materials and how to improve the quality of "blue" compost and to gain expertise in FT-IR analysis and spectrum interpretation for humic substances. MARIGREEN_TECB was a collaboration between NORSØK and USAMV in Bucharest. The workshop was organized by the Research Center for Studies of Food Quality and Agricultural Products at USAMV's campus in Bucharest and was held from 23 to 26 October 2023. The topics for the workshop were chosen because they are directly relevant to the MARIGREEN main project and several of the work packages. However, they also have global relevance. While the focus was on marine-based compost, the methods covered during the workshop are relevant to all types of composts, organic-based fertilizers and soil conditioners. Methods to improve compost quality and improve humification can be applied to compost made with all raw materials. The same applies to evaluation of compost quality by more tr

This practice abstract explores the microbial modulation for climate resilient agriculture and for healthy and plant based food chain in constantly growing world population , focusing on soil microbiome interactions and plant health. Utilizing microorganisms and natural stimulants from agricultural waste, the aim is to enhance soil microbiome resilience to environmental stresses. Through circular economy principles, this initiative promotes sustainable food systems and nutrient biofortification.

Mikrobielle und pflanzliche Biostimulanzien zur Verbesserung der Pflanzenernährung gewinnen zunehmend an Bedeutung. Eine aktuelle FiBLStudie hat die Wirksamkeit von fünf Präparaten untersucht.

Eine neue FiBL-Studie zeigt, wie Mykorrhizapilze dabei helfen, umweltschonend Erträge zu steigern.