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Referansegårdsprosjektet har prøvd ut og tilpasset et regenererende dyrkingssystem til norske forhold med mål om å fremme jordfruktbarheten og øke moldinnholdet. Prosjektet har omfattet seks korngårder på Østlandet, fire økologiske og to konvensjonelle. Følgende metoder har blitt brukt: 1) Gjødsling som fremmer jordlivet – utbalansering av næringsstoffene, 2) permanent grønt plantedekke med en allsidighet av arter, 3) skånsom jordarbeiding, bl.a. flatekompostering, 4) urteferment for å styre de mikrobielle prosessene og unngå forråtnelse (grønnmasse og husdyrgjødsel), 5) plantevitalisering og bladgjødsling for å øke fotosynteseraten, 6) dybdeløsning og 7) observasjoner av endringene i jorda, kulturen og ugraset (spadeprøve, microBIOMETER m.m.). Målinger viser mer jordliv (bakterier, sopp), bedre jordstruktur og vanninfiltrasjon, signifikant mindre fritt nitrogen (nitrat og ammonium), signifikant økning i jordkarbon (74 kg C per dekar per år i snitt) og reduksjon i frøugras m.m. Praksis viser at med flatekompostering kan et grønt plantedekke avsluttes uten glyfosat eller plog. Plantene blir i større grad ernært av jordlivet, og behovet for innkjøpt gjødsel er redusert (økologisk og konvensjonelt). Problemjord (stiv leire) er tatt inn i produksjon igjen gjennom mineralsk utbalansering. Dekningsbidraget, uten regionalt miljøprogram (RMP), er 5-33 % høyere for økologisk regenerativ korndyrking enn for konvensjonell. Avlingsnivået er 52-67 % av konvensjonelt korn. Prosjektbøndene er mer fornøyde enn før, men det kreves godt bondehåndverk for å lykkes, og bønder som er endringsvillige og proaktive. Prosjektbøndene har i praksis på totalt 90 enkeltskifter demonstrert at en ny agronomi er mulig, som bevisst fremmer de levende prosessene i jorda, tar bedre var på miljøet og gir god avling av god kvalitet.

Best practice guide: Få hjælp til at overholde fosforlofterne vha. nye fodringsstrategier.

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.

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.

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.

Efterafgrøder yder mere end blot reduktion af kvælstofudvaskning. Ved at blande de rigtige arter kan efterafgrøder øge jordfrugtbarheden, mindske ukrudtstrykket og øge kulstofopbygningen i jorden.

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.

Indlægsseddel for tilskudsfoderblanding med lavt fosforindhold til økologiske æglæggere. Blandingen er udviklet på baggrund af resultaterne i ORPHEUS projektet.

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.

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

Le projet SPoT mobilise des pratiques agro-écologiques pour tester sur le long terme (12 années à partir de 2023), en ferme expérimentale, une transition vers des systèmes mobilisant différents niveaux de couplage cultures et élevages afin de répondre aux enjeux précités. Cette approche a été initiée en Ardenne belge. Région dans laquelle l’avenir des systèmes allaitants, basés sur la valorisation de fourrages autoproduits, est questionné. Le processus de co-construction transdisciplinaire mis en place dans le cadre de SPoT a permis d’identifier et tester trois systèmes qui questionnent les synergies entre cultures à vocation alimentaire et élevage de bovins en vue d’optimiser la circularité des flux et la production d’aliments pour l’Humain (food) et de répondre aux enjeux climatiques. Cette contribution veut rendre compte, par une analyse interdisciplinaire, de certains freins et leviers vécus lors de la première année de notre expérimentation.

Strawberry is one of the most important berry crop grown around the world and their consumption increases every year. The introduction of new practices promoting farm sustainability and long-term soil health in strawberry production systems is very essential. Towards environment- and climate-friendly farming practices intercropping can be used to improve soil microbiological activity and biodiversity, and reduce the use of pesticides and mineral fertilizers, while the right choice of intercropped plants is of great importance to achieve these goals. The trials on strawberry intercropping were established in Latvia in 2021. Three treatments with different intercropping plant rotations, including crimson clover, pea, garlic, marigold, and winter rye mix with vetch, were compared to conventional strawberry growing using straw mulch. Trial was installed in three locations: two organic farms and the Institute of Horticulture (LatHort). Thus representing climatically different regions and different soil conditions. Strawberries were grown in 1.2 m distant rows, where in the intercropping treatments, each second interrow was occupied by companion plants. Soil microbial activity was evaluated during vegetation seasons by determining soil respiration rate (SRR) and dehydrogenase activity (DHA) several times per season in 2021 and 2022. Strawberry vegetative development was evaluated at the end of each vegetation season. During the investigation period, soil microbial activity fluctuated during vegetation seasons, depending on growing conditions.

Introduction One main obstacle to sustainable nutrient management in organic farming is the scarcity of nutrients. Further, commonly used nutrient sources in organic farming like composts or straw-rich animal manure show low nitrogen (N) fertilizer value. Anaerobic co-digestion of animal manures with biomass from green manures could increase the N fertilizer value of the animal manures while the addition of green manure would result in a higher quantity of fertilizers available in organic farming. Yet, studies investigating N fertilizer values under organic management are scarce. Therefore, this study aimed to determine the N fertilizer value of different products from anaerobic digestion (digestates, separated liquid fraction of digestates) as well as cattle manure and mineral fertilization under organic management. In addition, the difference in fertilizer value due to application timing (before vs. after ploughing) and crop management (organic vs. conventional) was tested. Methodology Two field studies were performed on loamy sand soil at the research station Foulumgaard (56o49’N, 09o58’E). Study 1 compared the effect of digestates (co-digestion of cattle slurry and clover grass silage), and liquid fraction from separated digestates with the effect of an unfertilized control, cattle slurry, and mineral fertilization on spring barley yield in two consecutive years under organic management. Study 2 investigated the differences in the fertilizer value of digestates (2on cattle slurry), and cattle slurry due to application timing (before vs. after ploughing), N dose (100 vs. 200 kg N ha-1), and management (organic vs. conventional) in spring barley. The fertilizer value was calculated as N fertilizer replacement value (NFRV) for grain N and total N yield. NFRV is estimated as shown in the equations belowfrom the N use efficiency (NUE) of manures relative to NUE of mineral fertilizer N (determined as the slope of the mineral N response curve). (1) NUE=(Nuptake fertili

Indlægsseddel for forsøgsfoder med det lavest mulige fosforindhold til økologiske æglæggende høner i universitetsforsøget.

Indlægsseddel for tilskudsfoder med lavt fosforindhold til økologiske æglæggende høner. Blandingen er udviklet på baggund af resultaterne i ORPHEUS projektet.

This factsheet deals with adjustments to ensure a sufficient P supply, such as the role of crop rotation, precrop effects or general basics of fertilisation.

Improving nitrogen supply is often a central motivation when agricultural operations want to optimise their nutrient management. The tool explains how nitrogen supply can be improved through well-chosen crop rotation, catch crops and legumes and fertilisation.

Background: Fertilization with organic waste compost can close the nutrient cycles between urban and rural environments. However, its effect on yield and soil fertility must be investigated. Aim: This study investigated the long-term effect of compost on soil nutrient and potentially toxic elements (PTEs) concentration, nutrient budgets, and nitrogen (N) mineralization and efficiency. Methods: After 21 years of annual compost application (100/400 kg N ha–1 year–1 [100BC/400BC]) alone and combined with mineral fertilization, soil was analyzed for pH, organic carbon (SOC), nutrient (total N and P, Nmin, extractable CAL-P, CAL-K, and Mg), and PTE (Cu, Ni, Zn) concentrations. Yields were recorded and nutrient/PTE budgets and apparent netmineralization (ANM, only 2019) were calculated. Results:Nefficiency was the highest in maize and formineral fertilization. Compost application led to lower N efficiencies, but increased ANM, SOC, pH, and soil N, and surpluses of N, P, and all PTEs. Higher PTE concentrations were only found in 400BC for Cu. Nutrient budgets correlatedwith soil nutrient concentration. A surplus of 16.1 kg P ha–1 year–1 and 19.5 kgKha–1 year–1 resulted in 1mg kg–1 increase in CAL-P and CAL-K over 21 years. Conclusion: Compost application supplies nutrients to crops with a minor risk of soilaccumulation of PTEs. However, the nutrient stoichiometry provided by compost does not match crop offtakes causing imbalances. Synchronization of compost N mineralization and plant N demand does not match and limits the yield effect. In winter wheat only 65–70% of Nmineralization occurred during the growth period.

The compost tea production process involves the use of a bioextractor (containing water), that is a tank equipped with an aeration device (pump). The on-farm compost is placed in a filter bag (hemp or nylon) and soaked in the water. Oxygenation is obtained by activating the recirculation of the aqueous medium of extraction via a pump. The extraction is carried out with a ratio of 1:5 v/v (20%). In order to ensure proper oxygenation, the timer should be set to a value of 15 minutes (on) every 3 hours (off). A further dilution can be necessary, after measuring the electrical conductivity, up to a ratio of 1:15 v/v, before using compost tea in soil (and on crop leaves). In sweet cherry orchards and in vineyards compost tea must be provided about three times during each season.

Agroecology can be defined as an integrated approach to agriculture and food systems, combining ecological and social principles to agricultural management and food systems design. Thanks to its holistic approach towards sustainability, agroecology can help tackle climate change challenges, from both mitigation and adaptation perspectives. Agroecological practices such as the use of cover crops and green manures have the potential to increase carbon stored in the soil, as well as soil fertility, mitigating climate change and at the same time improving crop productivity. Nonetheless, it has been shown that practices that can have a positive effect on carbon sequestration might increase emissions of other greenhouse gasses, such as nitrous oxide. This webinar will provide an overview on agroecological practices and climate change, and present results from field experiments on the effect of cover crops on carbon and nitrogen in the soil, with related implications for climate change mitigation.

Cover crops are cultivated during unproductive periods to provide ecosystem services, such as preventing nitrogen (N) leaching, and have the potential to increase soil organic carbon (C), thus contributing to climate change mitigation. Their effect on soil C storage depends on C input, which is challenging to quantify due to belowground sampling (roots and C deposited in the soil). Leguminous cover crops (in pure stands or in mixtures) increase the productivity of following main crops due to high N input, but also the risk of N losses, compromising the mitigation effect. As C and N services vary with cover crop type, tradeoffs could be minimized by species selection. The aim of this study was to assess C input from different cover crop species and mixtures, as well as N uptake in their biomass, and their effect on soil mineral N (SMN) and yield of the following crop. We conducted a field experiment in 2020-2021 at Foulum, Denmark (temperate oceanic climate, sandy loam soil), with seven treatments (five cover crops, control with volunteers, and bare soil) replicated four times. Cover crops undersown in spring barley (Hordeum vulgare L.) in May 2020 were: Lolium perenne L. (ryegrass, RG), Trifolium pratense L. (red clover, RC), Plantago lanceolata L. (plantain, PL) and the mixtures RG-PL and RG-PL-RC. On August 24, 2020, after barley harvest, PVC cylinders (diameter: 29.5 cm, height: 30 cm) were inserted in each plot (25 cm depth) and used for 13C-CO2 multiple-pulse isotopic labeling. Two sessions per week were conducted until cover crop sampling in November 2020, when C and N in above- and belowground biomass, as well C deposited in the soil were determined. Monthly soil sampling (20 cm depth) was performed from August 2020 until April 2021 to assess SMN. Then barley was sown to evaluate cover crops residual effect. Aboveground biomass was lowest in RG (1.5 Mg ha-1), and highest in RG-PL-RC (5.4 Mg ha-1). Total C input (above- and belowground) ranged from 1.6 to 4.3

This final report from the project “Residual materials from marine industries as fertilisers in organic agriculture” is an example of blue-green collaboration. Such collaboration has been a strategic goal for many Norwegian research and innovation activities since the terms bioeconomy and circular economy came high on the agenda. Significant amounts of residual raw materials from marine industry are still poorly utilized. Traditionally, seaweeds and residues of fish and other sea animals were applied as feed and fertilisers along the coast of Norway, as elsewhere in coastal regions. These valuable materials should still be applied in agriculture, but the application needs to be adapted to a more professional and large-scale production. Organic agriculture aims at being selfsufficient in nutrients and other inputs for the production. A further aim is to recycle nutrients and organic matter not only inside the farm by feeding manure-producing animals, but by recycling nutrients lost from the farm by sales of products, and by runoff and emissions. The RESTOR project (2018-2022) has provided resources for establishing a significant research and developmental work on marine-derived fertilisers at the Norwegian Centre for Organic Agriculture (NORSØK). Marine derived fertilisers, especially from sustainable collection or capture of natural renewable resources, may fit well to the aims of organic agriculture. The project has tested residual materials rich in bones from industry processing white fish species (cod, saithe, longfish etc.), and residual material from chemical extraction of rockweed. The materials have been tested as fertilisers and soil amendments, with controlled trials indoor and in the field. A general result is a very rapid growth effect of fishbones in the year of application, with a residual effect in subsequent years resembling that of dried poultry manure. The algae fiber has no immediate fertiliser effect but has a significant residual growth effect. D

• Clover grass as a co-substrate in biogas production is an important source of biogenic nitrogen contributing to carbon sequestration and biodiversity • Anaerobic digestion has a high potential for reduction of GHG emissions • High nitrogen efficiency of ammonia-rich fractions • Dried fiber fraction immobilizes nitrogen but is usable as phosphorus source for legume crops

Ved et relativt lavt input på 85 kg total-N i afgasset gylle kan en høj andel af vellykkede efterafgrøder (+75%) og salgsafgrøder hvert år øge udbytterne i forhold til et system med helårsgrøngødning.

This report presents the methods and results from preliminary trials with composting marine residual raw materials under the auspices of MARIGREEN, a project funded by the ERA-NET BlueBio cofund program. The main goal of MARIGREEN is to upgrade poorly utilized residual raw materials from blue value chains (fish, shells, algae) for use as fertilizer and biostimulants in organic farming. The project is led by UPB (Romania) and is in collaboration with USAMV (Romania), AUTh (Greece), DTU (Denmark), UCPH (Denmark), NORCE (Norway), and the industrial partners Alumichem AS (Denmark), Norgeskjell AS (Norway), Sigurd Folland AS (Norway), Fjordlaks AS (Norway), and Algea AS (Norway). The compost experiments were carried out at three different levels: small-scale (2 litres) in so-called Dewar flasks; medium-scale (140 liters) with a Jordakompost® insulated compost drum; and large-scale (approx. 7 m3) with windrow composting. The first experiments in the Dewar flasks were based on known raw materials such as horse dung, sawdust, and straw and were intended to familiarize ourselves with the equipment and the method, which is called a self-heating test. This test is usually used to estimate the maturity and stability of finished compost, but here we wanted to look at heat development in fresh material. The trials with the familiar raw materials were followed by trials with the marine residual raw materials, tangle kelp, two types of algae fiber from processing rockweed (brown seaweed), ground fish bones from hydrolyzed cod heads, and dried fish meal from fish in the cod family. These materials have, to our knowledge, not yet been tested in Dewar flasks. As an alternative bulking material in the Dewar bottles and in the compost drum, we experimented with expanded clay aggregates (Leca®). The experiment with horse dung confirmed that the Dewar flasks can be used to estimate the potential for heat generation in fresh material. The marine residual raw materials also developed heat

The present agri-food system in Norway, and globally, is facing severe challenges when it comes to ecological, economic, and social sustainability. There is a strong need for knowledge and evidence of how different agricultural production systems contribute to sustainability. However, assessing the sustainability of farming and food systems is a challenging and complex task. Methods intending to do so need to be carefully evaluated. In this study, FAO’s Tool for Agroecological Performance Evaluation (FAO, 2019) was implemented and evaluated for its suitability in a single farm case. The study constituted the first author’s thesis for completion of the MSc in Agroecology at the Norwegian University of Life Sciences (Hansdotter, 2022).

In ökologischen Kartoffeln wurde die Düngung mit Haarmehlpellets (HMP) und organischem Mulch verglichen. In der Dürre 2020 wurde weniger N in den Mulchvarianten mineralisiert, was zu einem erhöhten N-Auswaschungsrisiko vor Winter, aber keinen sign. Ertragsunterschieden führte.

One of the key ways to improve the sustainability of agricultural systems is through diversification, taking advantage of synergies between farm enterprises. Among diversified systems, multispecies livestock farms with at least two animal enterprises have rarely been studied. We explored 95 organic farms from six countries, accounting for the proportion of animal enterprises, sales management, workforce size, and work organization. The study reveals various types of interactions between animal enterprises. Complementarities were observed between ruminant and monogastric enterprises, particularly fertilizer transfer from monogastric manure to grasslands. Milk production was often associated with on-farm processing and short distribution channels, which enhanced farm viability and reduced its dependency on herd productivity. Eleven out of the 95 farms combined above-average production efficiency, on-farm processing, and the majority of sales in short distribution channels. Their labor productivity converged toward 22 livestock units per annual work unit, regardless of the number of workers. Combining farm structure; livestock production efficiency; social elements, such as the workforce; and sales management led us to distinguish four types of farms: (i) small and very autonomous grassland farms with on-farm processing and short distribution channels; (ii) dairy farms associated with a high-density pig or poultry enterprise, whose feed purchase contributes to high rates of cattle feeding self-sufficiency and stocking rate; (iii) large farms with an extensive, grassland beef enterprise associated with either sheep or monogastrics; and (iv) dairy sheep associated with goat or beef cattle on rangelands, with high added-value products enhancing salaries. This study highlights for the first time the diversity of organic multispecies livestock farms and how consistent patterns of interactions among farm structure, livestock management, sales management, and workforce manage

Die Bruttoerträge, unter Einbezug unbepflanzter Fahrgassen für die Mulchausbringung, wirken sich entscheidend auf die Wirtschaftlichkeit einer regenerativen Kartoffelanbau-Methode unter Transfermulch aus. Außerdem relevant sind die Gestaltung der Mulchprozesskette sowie die Mulcherträge und -kosten.

Im Versuch wurde nachgewiesen, dass der Phosphor-Gehalt der Sprossbiomasse bei den mit Struvit gedüngten Weizenpflanzen im Vergleich zu den anderen Düngungsvarianten signifikant höher ist. Dieses Ergebnis deutet darauf hin, dass Struvit eine hohe Phosphor-Pflanzenverfügbarkeit aufweist.

Seafood processing generates significant volumes of residues including bones, heads and other non-consumable fish parts, rich in nitrogen, phosphorus and calcium. Some residues are recycled to aquaculture or animal feed, but around 4 000 tP/y in Norway are currently not valorised. Nitrogen, potassium and magnesium can be extracted from brown seaweed (harvested or cultivated), and combined with processed seafood by-products to produce a nutrient-balanced recycled fertiliser, which has shown positive results in agronomic trials. These marine sources represent significant potential for nutrient recycling in coastal countries. Certain seafood processing byproducts are specifically authorised for use as fertilisers in the EU Organic Farming Regulations: fish meal – without limitations, mollusc waste and shellfish chitin from organic aquaculture or sustainable fisheries only, seaweed and seaweed processing by-products with some restrictions.

The presentation informs about field experiments carried out by NORSØK with new types of fertilisers applicable for organic growing of arable crops (cereals), such as struvite from sewage, and left-over materials from the sea such as fishbones and seaweed.

Die Steigerung der Produktivität und die Erhaltung der Böden sind die größten Herausforderungen, denen sich der ökologische Landbau in Zukunft stellen muss. In diesem Workshop werden die Möglichkeiten des Leguminosenanbaus in Fruchtfolgen und die damit verbundenen Risiken und Chancen diskutiert.

In a two-year model crop rotation consisting of overwintering legumes as cover crops followed by maize in the first year and grain peas in the second year, the phytopathological risks and the potential of expanding the cultivation of legume cover crops in minimum tillage systems were examined.

Mulch aus Gründüngungen wird zur Klimawandelanpassung, Nährstoffversorgung, zum Pflanzenschutz und Bodenfruchtbarkeitsmanagement eingesetzt. Der Workshop stellt den aktuellen Stand des Wissens und der Praxis vor. Er zielt darauf ab, Forschung, Beratung und Landwirte enger miteinander zu verbinden.

In Feldversuchen mit Zwischenfrüchten wurden über Winter hohe Stickstoffverluste aus der Sprossmasse festgestellt. Zusammen mit einem weiten C/N-Verhältnis im Stängel, könnte dies erklären, warum eine zusätzliche Mineralisierung im Frühjahr im Vergleich zur unbehandelten Kontrolle relativ gering ausfiel.

Die Integration von Spitzwegerich in Feldfuttergemenge führt durch seine tief reichenden Wurzeln im Vergleich zu Gemengen mit Gräsern zu höheren Schnittguterträgen in Trockenperioden. Des Weiteren senkt Spitzwegerich durch seine nitrifikationshemmende Wirkung die Auswaschung von Nitratstickstoff.

Unter Einsatz des Transfermulch-Verfahrens wurden in einem zweijährigen Versuch Lachgasemissionen gemessen. Die bisherigen Ergebnisse zeigen, dass unter Verwendung von Transfermulch erhöhte N2O-Emissionen stattfinden. Signifikante Ertragssteigerungen konnten bisher nicht festgestellt werden.

Im Jahr 2017 hat die Universität Kassel einen Langzeitversuch zu viehlos wirtschaftenden Betriebssystemen an der Hessischen Staatsdomäne Frankenhausen etabliert. In dem Langzeitversuch werden drei viehlose Betriebstypen mit einem viehhaltenden, ökologischen Gemischtbetrieb verglichen.

The European Commission recently set a target of increasing the area of organic agriculture to 25% by 2030. To achieve this, it is imperative to understand current nutrient use patterns and identify sustainable nutrient supply opportunities. To that end, this study assessed the sustainability of the current nutrient origin and supply of 71 arable organic farms in 8 European regions. Defcient nutrient supply was found on 24%, 66%, and 56% of farms for nitrogen, phosphorus, and potassium, respectively. On average, we show a moderate surplus for nitrogen (28 kg ha−1), while phosphorus and potassium balances were close to zero (−1 and 2 kg ha−1, respectively). Large variation between countries and farm types shows a divide between more intensive systems relying on external inputs, and less intensive systems facing nutrient defcits and lower outputs. We show, for the frst time, the extent of current use of external input types, where conventional manures supplied 17–26% of external nutrients and inputs from non-agricultural origin supplied 31–41%. A large proportion of nutrient sources within the last group are materials derived from urban wastes. The sustainable expansion of the organic sector will require increased use of locally available recycled fertilizers from urban wastes, and acceptance of such sources by organic farmers is shown to be high, provided they are considered safe.

Introduction There is a large political motivation goal in the EU to increase organic farming area to 25%. However, for this, additional nutrients, preferably from recycled sources are needed. Before their wide use in organic farming concerns about contamination with potentially toxic elements (PTEs) and their influence on soil fertility must be assessed. In this study, the effect of recycled fertilizers from urban waste on crop yield, nutrient balances, soil fertility (especially soil nitrogen and carbon), and risk of contamination with PTEs were examined. Therefore, data from three long-term (>20 years) were analysed and combined with a model simulation exercise to gain more insight into the nitrogen (N) and carbon (C) cycle. Methodology Data from three long-term field trials using different recycled fertilizers, including compost from household and green waste, human urine, and sewage sludge was analysed. The first trial investigates different compost application rates in combination with mineral fertilization and was established in 1997 at the research station Heidfeldhof, South Germany. The second trial compares different application rates of sewage sludge and was established 1981 in Speyer, Germany. The third trial is called CRUCIAL and was established in 2002 at the station Taarstrup, Denmark. It compares compost from household and green waste, human urine, and sewage sludge to mineral fertilization and cattle manures. Crop yield, and soil parameters like soil carbon, soil N, phosphorus, potassium, and PTE content were collected and analysed. The results of the CRUCIAL trial were used to calibrate the soil-plant-atmosphere model DAISY which in turn was used to estimate water, C and N flows. Results and discussion Recycling urban waste into fertilizers can serve as a viable source of nutrients. In terms of nitrogen recovery rates, sewage sludge and human urine performed similarly to cattle slurry with N recovery rates of about 0.5 – 0.6, while household waste

In einem Praxisversuch wurde die Luzerneetablierung als Kleegrasgemenge mit Wickenroggen und „Landsberger Gemenge“ untersucht. Die Partner trugen entscheidend zum ersten Futterschnitt bei. Luzerne war in allen Varianten etabliert mit geringerer Luzernebiomasse bei höherem Deckungsgrad der Partner.

Der Öko-Gemüsebau zeichnet sich durch ein anspruchsvolles Nährstoffmanagement aus mit hohem Nährstoffbedarf des Gemüses und vergleichsweise kurzen Wachstumsperioden. Der Ansatz der Hoftorbilanzierung zielt darauf ab, den Status quo des Düngemanagements für N, P und K auf Gemüsebetrieben aufzuzeigen.

Untersucht wurde die Düngewirkung von organischen Nebenprodukten aus der Insektenzucht mit unterschiedlichen Eigenschaften zu Staudenbasilikum. Eine hoher Frischmasseertrag wurde nach Düngung von Insektenfraß aufgrund eines günstigen Verhältnis von N-P-K im Düngemittel festgestellt.

Die Datengrundlage der Tools N-Expert und NDICEA stammt teilweise aus dem konv. Gemüsebau und ist ggf. nicht mehr aktuell. Auf Grundlage vieler Versuche mit Kohl- und Salatvarianten wurde untersucht die Datengrundlage für die Stickstoffgehalte für Feldabfuhr und Ernterückstände validiert.

Im Projekt VORAN (Verbesserung ökologischer Fruchtfolgen mit Transfermulch für ein angepasstes regeneratives Nährstoffmanagement) wird seit 2019 in Feld- und Gewächshausversuchen im LfULG untersucht, welche Bodenschutzeffekte erzielt werden können.

Für 15 ausgewählte österreichische Öko-Ackerbaubetriebe wurden N-, P-, K- und Humusbilanzen berechnet. Im Durchschnitt waren die Nährstoffbilanzen leicht negativ, die Humusbilanzen positiv, mit großer Spannweite. Das Nährstoffmonitoring und -management auf diesen Betrieben ist verbesserungsbedürftig

Durch die Verknüpfung von Daten zum Nährstoffmanagement von knapp 1000 Biobetrieben der Schweiz mit Daten zu Hof- und Recyclingdüngerverschiebungen erhielten wir eine umfassende Beurteilung der Nährstoffversorgung von Biobetrieben in der Schweiz im Jahr 2017.

Stickstoffsaldo gehört zu den wichtigstene Agrarumweltindikatoren. Durch eine systematische Literatursuche zur Stickstoffeffizienz wurden 3107 Studien identifiziert. Nach Sichtung wurden 31 Studien ausgewertet. N-Input, Rotationsdauer und N-Output wurden als die wichtigsten Einflüsse bestimmt.

Ziel des Forschungsprojekts war es, einen Algorithmus zur Berechnung des N-Düngebedarfs im ökologischen Landbau für Wintergetreide zu entwickeln. Auf der Grundlage von Kulturart, ertrags- und qualitätsabhängiger Düngermenge werden Empfehlungen für Düngermenge, -zeitpunkt und -staffelung gegeben.