Search

The non-turning or only superficial turning of soil is considered to be a gentle tillage method. Nevertheless, conventional ploughs are widely used in organic farming for crop production reasons. For the further development of reduced tillage, and up to no tillage, the effects of three cover crop species and their incorporation with different tillage intensities on nitrogen (N) dynamics, weed emergence and the yield of the subsequent main crop, oats, were examined in a repeated organic one-year trial. Sinapis alba, Trifolium resupinatum, Vicia sativa and bare fallow were tested and incorporated using (1) a plough (PL), (2) reduced tillage (RT), (3) mulching + drilling (MD) and (4) direct drilling (DD). V. sativa was the most promising cover crop in combination with RT, MD and DD. In Trial 1, the soil mineral N content and oat yields after the introduction of V. sativa were on a similar level as those in the PL treatments, and weeds were not yield-limiting there. In Trial 2, the biomass production of V. sativa was only about half of that of Trial 1 and did not offer sufficient weed control, but V. sativa was still successful in the RT treatments. In both trials, the yield differences were more pronounced between the cover crop treatments after RT than after PL. RT, therefore, was more dependent on an adequate cover crop species than PL. The no-till method was not only dependent on an adequate cover crop species but also on its proper biomass production for sufficient weed control.

Manure is a key source of N for crops, especially in organic farming systems, but also a driver of N2O emissions from soil. Treatment technologies removing manure organic matter affect soil N2O emissions, but the direction and magnitude of these effects remain uncertain. We explored the effects of four fertilizer materials derived from cattle manure on soil N2O emissions. Treatments included: untreated cattle manure (CA), cattle manure co-digested with grass-clover silage (DD); a liquid fraction (LF) produced by mechanical separation of digestate; and a concentrated fertilizer with NH4+-N and sulfate (NS) produced from stripped H2S and NH3. These fertilizers were surface-applied to a sandy loam (Foulum) and a clay loam soil (Askov) at 55% water-filled pore space (WFPS) in 28-day laboratory experiments with monitoring of CO2 and N2O. Samples were sectioned during or after incubation to describe mineral N and microbial dynamics. Although the WFPS in both soils was 58–61%, N2O emissions varied greatly, and this was explained by differences in water potential, and in the relative gas diffusivity which was approx. 0.011 and 0.030 in Foulum and Askov soil, respectively. Unexpectedly, treatment LF with the lowest manure organic matter input had the highest N2O emissions. Denitrification was the main pathway producing N2O as determined by 15N enrichment of soil NO3−. The vertical distribution of mineral N and microbial activities, and PLFA, indicated that N2O emissions from the organic fertilizers depended on their interaction with the soil, as modified by soil water potential and gas diffusivity at the time of application.

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 Mg ha-1, with RG-PL-RC (highest) being significantly higher than RG-PL and RG (lowest). The same pattern applied to total N input, ranging from 74 to 202 kg ha-1. All cover crop treatments had lower SMN than bare soil and volunteers in August 2020. SMN increased from August until April 2021 with all cover crops except RG, and decreased with bare soil and volunteers. SMN in April was 15 kg ha-1 higher with RC and RG-PL-RC than RG. Barley yield following leguminous cover crops was comparable to plots fertilized with 100 kg ha-1 of mineral N, while non-legumes to 40 kg ha-1. Overall, the mixture with RC provided the greatest C input and positive residual effect. The small change in SMN in April indicate that biomass N was converted into mineral N and taken up by barley during the growing season, thus not increasing the risk of N losses.

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 net mineralization (ANM, only 2019) were calculated. Results: N efficiency was the highest in maize and for mineral 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 correlated with soil nutrient concentration. A surplus of 16.1 kg P ha–1 year–1 and 19.5 kg K ha–1 year–1 resulted in 1 mg kg–1 increase in CAL-P and CAL-K over 21 years. Conclusion: Compost application supplies nutrients to crops with a minor risk of soil-accumulation 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 N mineralization occurred during the growth period.

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. Due to the content of cadmium (Cd), algae fiber is a class II soil amendment product. This implies that it may be applied with up to 20 tons of dry matter per hectare over 10 years, according to Norwegian regulation. An amount close to this level was tested in ryegrass in 2020. The tetany ratio, which is an assessment calculated to assess the risk of tetany in ruminants based on the concentrations of potassium (K), magnesium (Mg), and calcium (Ca) in plant material applied as feed, was then well above the critical level. Hence, we recommend that the material should not be applied at a higher rate than 10 tons per hectare over 5 years (half the maximal rate for each application), to avoid excess uptake of potassium in crop plants. When applied as the single fertiliser material, both fishbones and algae fiber are unbalanced and should be blended with other materials. The project tested a mix where 30% of the nitrogen (N) was derived from algae fiber and 70% from fishbones. This fertiliser gave good yields both in the year of application, and in one or more subsequent growing seasons. With higher prices on energy, there is increased interest for alternative sources of plant nutrients which may complete existing fossil resources. Most European countries are currently dependent on importing phosphorus (P) and potassium, which is a challenge in a world with increasing levels of conflicts. Significant amounts of nutrients are found in the sea, but we still need both research and developmental work to establish value chains for marine-derived fertilisers which may complete the currently applied fertilisers in both conventional and certified organic agriculture. We also need adapted regulations for such products. A proposal for new regulation on organic fertilisers in Norway includes strict limits for arsenic (As), which may significantly hamper the utilization of seaweed material in fertilisers and for soil amendment. We need more research to assess such limit values. The R&D work with marine-derived fertilisers is well established, and continues, both at NORSØK and with other research organizations.

I det igangværende projekt ’ Nutrient recycling for soil fertility and improved organic livelihood’ (Fertihood) er det besluttet at lave en detaljeret oversigt over relevante affaldsstrømme til rådighed for at øge næringsstofforsyningen i økologisk landbrug, herunder mulighederne for at anvende disse ressourcer. På baggrund af denne ’Kortlægning af mængden af organisk affald og restprodukter til gødningsformål’ er der lavet en screening af hvilke af disse ressourcer der pt er lovlige at anvende i økologisk jordbrug. Efterfølgende er der oprettet en ekspertgruppe, som har vurderet hvor stor en andel af disse der forventeligt vil kunne tilgå økologiske bedrifter, ud fra et skøn om en relativt større betalingsevne, baseret på den nytteværdi de vil kunne have for økologiske landmænd. Desuden har ekspertgruppen vurderet hvilke af de ikke lovlige ressourcer, der i en lidt fjernere fremtid vil kunne lovliggøres, samt andelen af disse der vil tilgå økologisk jordbrug. Det forudsættes at EU-lovgivningen i de kommende år vil udvikle sig til fordel for større grad af recirkulering fra det omgivende samfund til økologisk jordbrug. Usikkerheder forbundet med datakvalitet og vurderingsmetoden beskrives nærmere. I det videre forløb overleveres data til Fertihood projektet, hvor Økologisk Innovations center skal stå for at vurdere hvordan de skønnede organiske ressourcer bedst muligt kan anvendes i fremtidig økologisk produktion.

Fertilisation with animal manure has a long-standing tradition as a way to close nutrient cycles on farms. However, the fate of nitrogen (N) from manure in the soil beyond the year of application remains poorly understood. The aim of this research was to understand the residual N fertiliser value of mineral fertiliser (Min) and cattle slurry (Slu) in relation to the partitioning of N from the fertilisers in different soil physical fractions. To this end, we characterised the fate of 15N-labelled Min and Slu in soil organic matter (SOM) physical fractions two years after field application and related it to plant uptake of residual N. A secondary objective was to compare two fractionation methods with respect to accuracy and easiness, namely a combined density and particle size fractionation, separating five fractions, and a simple particle size fractionation, separating two fractions. All fractions were analysed for 15N abundance. The residual N fertiliser value was determined as the uptake of 15N by ryegrass (Lolium multiflorum) during 6 weeks. Furthermore, we deduced the source of 15N taken up by the plants from changes in the percentage of N derived from labelled fertilisers in each of the SOM physical fractions obtained by simple size fractionation before and after the pot experiment. Two years after application, most 15N was found in the fractions, Soil Biology and Biochemistry, 177, ISSN:0038-0717, ISSN:1879-3428

Targeted use of animal manures as a nitrogen (N) fertilizer is challenging because of their poorly predictable N fertilizer value. An enhanced understanding of their N transformation processes in soil under field conditions is necessary to better synchronize N availability and crop N demand. 15N labeled cattle slurry, produced by feeding a heifer with 15N labeled ryegrass hay, was used in an on-farm trial on two neighboring fields, cropped with maize or grass-clover, in order to assess crop N uptake and N dynamics in the topsoil. Recovery of applied total N in plant biomass was higher for mineral fertilizer (Min) (45–48%) than for slurry (Slu) (17–22%) when applied at the same rate of mineral N. Also, N derived from fertilizer in plant biomass was higher for Min than for Slu, due to both greater NH3 emissions and greater initial immobilization of slurry N. Despite initial differences between the two in the relative distribution of residual fertilizer N in soil N pools, already in the following spring the majority (77–89%) of residual N from both fertilizers was found in the non-microbial organic N pool. Of the applied total N, 18–26% remained in the topsoil after the first winter for Min, compared to 32–52% for Slu. Thus, the proportion of fertilizer N not taken up by the first crop after application, enters the soil organic N pool and must be re-mineralized to become plant available., Nutrient Cycling in Agroecosystems, 125 (2), ISSN:1385-1314, ISSN:1573-0867

Améliorer les rendements grâce à un état de fertilité équilibré, tel est le sous-titre d’une nouvelle fiche technique consacrée aux analyses de sol. L’art de la fumure consiste aussi à mieux prendre en compte les interactions entre nutriments.

Nedklassifisert saueull kan fungere som gjødsel og som jorddekkeduk.

Reporting from the Open House Event 30. Sept. 2022 in Højbjerg visiting ComFerm who has produced the composting machine. Researchers from AU presented the first results on the effect of the compost on soil fertility and plant growth.

KRONIK: Mere effektiv biogasproduktion ved længere opholdstid i biogasanlæg reducerer ikke den langsigtede kulstofbinding i jorden. Til gengæld opnås en bedre gødningsvirkning ved optimering af afgasningen

CRUCIAL markforsøget er gødet med komposteret husholdningsaffald og spildevandsslam i 20 år, i niveauer som er højere end tilladt (svarende til over 100 års tilførsel). Derfor forventes det at eventuelle skadelige stoffer (mikroplast, tungmetaller, organisk forurening) i produkterne er akkumuleret til et niveau der svarer til, eller er højere end den akkumulering man kunne forvente ved mere end 100 års almindelig gødningspraksis. Vi har lavet en undersøgelse af jordens sundhed og fødenet på CRUCIAL forsøgsmarken. Der er særlig fokus på jordens samfund af nematoder, som kan indikere om der er indikationer på forurening som følge af gødskning med spildevandsslam. Undersøgelsen finder at der er ændringer både i jordens struktur og organismesammensætning, men at der ikke er nogen tegn på negativ påvirkning af jordens sundhed.

Animal manures are suspected to be a major source of nitrate leaching due to their low nitrogen use efficiency (NUE) by crops. However, actual measurements of nitrate leaching from animal manure under field conditions are scarce. In an on-farm field trial in Switzerland over 2.5 years, we used 15N labelling to trace the fate of N from cattle slurry in the soil-plant system and to test whether more nitrate was leached from slurry than from mineral fertiliser. The experiment was conducted on two neighbouring fields with loamy soil in an agricultural area of the Swiss midlands, where nitrate levels in the groundwater are persistently high. Both fields followed the same crop rotation (silage maize – winter wheat – grass-clover), but shifted by one year. We compared three fertiliser treatments: Control (Con), 15N mineral fertiliser (Min), and 15N cattle slurry (Slu). In order to provide a comprehensive fertiliser N balance over several years, we traced the labelled fertilisers into crop biomass, soil, and leached nitrate. In the year of application, 15N recovery in crops was 45–47% for Min, but only 19–23% for Slu. Complementary to this finding, recoveries in soil were greater for Slu than for Min, despite greater NH3 emissions from Slu. Fertiliser recovery in the succeeding crops was small (< 4.6% of the originally applied fertiliser N in the first residual year and < 2.4% in the second) and similar for both fertilisers. Depth translocation of fertiliser N was marginal, with the majority of 15N in soil still in the top 0.3 m after 2.5 years. Along with higher recoveries in soil for Slu, we found significantly more slurry N than mineral fertiliser N lost through leaching. However, less than 5% of cumulated amounts of nitrate leaching over the three crops, which reached up to 205 kg nitrate-N ha-1, originated from direct leaching of the labelled fertilisers. Our findings suggest that most nitrate leaching originated from the mineralisation of soil N., Agriculture, Ecosystems & Environment, 338, ISSN:0167-8809, ISSN:1873-2305

Low grade wool can be used as fertiliser or as an alternative to plastic soil covers

The low fertility in soils where date palms are grown in Morocco is the first cause leading to low yields when compared to other producing countries. The aim of this study is to investigate the effect of organic amendment on mineral nutrition and yield of Majhoul date palm cultivar under Moroccan oasis conditions in relation with soil fertility. A field study was carried out for 2 years at two farms located at different sites in Drâa-Tafilalet region (Jorf and Tinjdad). The effect of different fertilization treatments on soil organic matter mineralization, soil mineral nutrients, plant nutrition, and date palm yield was investigated. The four treatments that were studied in this experiment are described as follows: mineral nitrogen (urea), organic amendment (compost), organic amendment combined with mineral nitrogen, and control with no fertilization. The compost, alone or combined with urea, enhanced the soil fertility through the improvement of the soil organic matter content and its mineralization and the increase in soil macro- and microelement concentrations at two depths compared to the urea alone and the control. The mineral nutrition of date palms was significantly enhanced by applying compost and/or urea. The application of compost combined with urea, for 2 years, increased the yield at Jorf farm by more than 78% and at Tinjdad farm by 41%. The adoption of the fertilization management, based on the application of both compost and urea, could restore the degraded soils, increase the date palm yield, and ensure more returns to farmers.

The MERMOLD project (2019-2022) was a collaboration between industry and research partners. The project was owned by Sunndalspotet AS and managed by the Norwegian Centre for Organic Agriculture (NORSØK). The other partners were Standard Bio AS, Ecopro AS and Landbruk Nordvest. Production of potatoes is a specialised industry, and commonly occurs on farms without animal husbandry. Hence, cereals are often the only other crop being grown, and with a lack of animal manure and growing of perennial ley, in combination with intensive soil tillage for potatoes, soil organic matter (SOM) tends to decline. The main objective of this project was to assess if cover crop and organic amendment practices could increase SOM storage, and possibly affect potato yields and soil-borne diseases. To do so, we established a field experiment in July 2019 to: (i) assess under field conditions with and without cover crop the impact of a single application of various organic materials to soil (biochar+liquid digestate, solid digestate, or farmyard manure) on SOM storage; (ii) quantify the impact of cover crop and application of organic materials on potato yields and potato diseases; (iii) discuss a suitable cover crop and organic soil amendment practice for potato cropping systems in this part of Norway. Furthermore, we performed a laboratory incubation to (iv) measure under controlled conditions the effect of organic amendments on carbon dioxide (CO2) emissions from the experimental soil. Our results show that: a single addition of organic materials increased SOM storage, especially in the farmyard manure and biochar+ liquid digestate treatments, while the presence of cover crop did not significantly affect SOM storage. Yet, the cover crop significantly increased potato yield in 2021 and reduced the severity of potato diseases by 10% in the post-harvest potatoes in 2020 and 2021, while the number of marketable potatoes after storage in 2021 was increased by 37%. Organic amendments did not significantly affect potato yield or quality, but the proportion of marketable potatoes tended to be higher in the treatments where organic materials were applied 2 years after the application.

Anaerobic digestion (AD) is an important tool for reducing greenhouse gas emissions from agricultural production. A prolonged retention time by adding an extra anaerobic digestion step can be utilized to further degrade the digestates, contributing to increased nitrogen mineralisation and reducing decomposable organic matter. These modifications could influence the potential N fertiliser value of the digestate and soil carbon sequestration after field application. This study investigated the effects of prolonging retention time by implementing an additional anaerobic digestion step on carbon and nitrogen dynamics in the soil and soil carbon sequestration. Two digestates obtained from two biogas plants operating at contrasting hydraulic retention times, with and without an additional digestion step, were applied to a loamy sand soil. N mineralisation dynamics were measured during 80 days and C mineralisation during 212 days. After 80 days of incubation, the net inorganic N release from digestates obtained from a secondary AD step increased by 9–17 % (% of the N input) compared to corresponding digestates obtained from a primary AD step. A kinetic four-pool carbon model was used to fit C mineralisation data to estimate carbon sequestration in the soil. After 212 days of incubation, the net C mineralisation was highest in undigested solid biomass (68 %) and digestates obtained from the primary AD step (59–65 %). The model predicted that 26–54 % of C applied is sequestered in the soil in the long-term. The long-term soil C retention related to the C present before digestion was similar for one- and two-step AD at 12–16 %. We conclude that optimizing the anaerobic digestion configurations by including a secondary AD step could potentially replace more mineral N fertiliser due to an improved N fertiliser value of the resultant digestate without affecting carbon sequestration negatively.

Die gesellschaftliche Forderung nach einer nachhaltigen und produktiven Pflanzenproduktion bei gleichzei-tig zunehmenden Wetterextremen setzt die Betriebe stark unter Druck. Der pfluglose biologische Ackerbau bietet hier viel Potential, muss aber in Punkto Beikrautregulierung und Stickstoffverfügbarkeit optimiert wer-den, um für die Bio-, IP- und ÖLN-Praxis attraktiv zu sein. Das Projektziel ist zu untersuchen, ob mit geziel-tem Hacken die Stickstoffernährung der Pflanzen und die Beikrautregulierung auch bei reduzierter Dünger-menge effizient gesteuert werden kann und der dabei angeregte Humusabbau auf einem akzeptablen Niveau bleibt. In einem 12-jährigen Langzeitversuch zur reduzierten Bodenbearbeitung und Düngung wer-den im Projekt verschiedene Hackintensitäten in den Kulturen Silomais und Winterweizen zusätzlich inte-griert. Die N-Mineralisierung wird über Nmin-Analysen und der Humusabbau über CO2 Gasmessungen ver-folgt. Die N-Aufnahme wird über Orthofotos sowie N-Analysen in der Trockenmasse und die Produktivität über den Biomasseertrag ermittelt. Die Messung der Beikrautbiomasse wird als Indikator für die Effektivität des Hackens verwendet und die Qualität des Mais mittels Silierversuchen bestimmt. Daneben werden auf Praxisbetrieben in Streifenversuchen mit verschiedenen Hackintensitäten Ertragsbestimmungen und N-Analysen in der Trockenmasse bei Mais und Weizen durchgeführt. Die ökonomische Einschätzung erfolgt über Deckungsbeitragsrechnungen. Die Versuchs- und Praxisdaten helfen die Nachhaltigkeit der Pflanzen-produktion im Bereich der Pestizid- und Düngerreduktion, sowie die Anpassung an den Klimawandel zu op-timieren.

In agriculture, with growing concerns about the excessive use of synthetic fertilizers and the decline in soil organic matter, the demand for organic forms of soil amendments, such as compost, is increasing. While traditionally it takes months to produce compost, a new composting technology (ComFerm Aps) can produce compost in few weeks. This thesis investigated the quality of this compost and its effects on the soil-plant system. A compost-soil incubation experiment was conducted with focus on N mineralization and soil microbial activity, as measured by dehydrogenase activity. A maturity assessment of compost stability (respirometry test Solvita®) and phytotoxicity (cress germination test) was conducted.

Achieving adequate phosphorus (P) levels without manure from conventional farms is challenging for organic vegetable farmers. The potential of plant-based fertilisers (PBFs) to replace animal-based fertilisers (ABFs) was examined based on a 5 year, multifactorial crop rotation experiment. Two crop rotations on a sandy loam soil were compared: a standard organic rotation (ST) with clover undersown in spring barley, cabbage, celeriac, corn, and onion. This rotation received inversion tillage, ABFs, and bare soil between cash crops. In contrast, a new organic management system aiming at sustainable intensification (SI) had pure clover without barley, and onion was intercropped in relay with lettuce. This rotation received reduced tillage, PBFs, and cover crops. Soil and crop P were analysed, yields were quantified, and a sequential soil P fractionation was conducted to analyse P dynamics.

Documentation of the effect of plant-based fertilizers and compost on plant growth and soil fertility in organic vegetable production (PP presentation at the Organic field day, Aarup June 2022)

This paper reviews relevant knowledge about the production and uses of fertilizers from fish and fish waste (FW) that may be applicable for certified organic farming, with a focus on crop and horticultural plants. Fish industries generate a substantial amount of FW. Depending on the level of processing or type of fish, 30–70% of the original fish is FW. Circular economy and organic farming concepts were used to evaluate the potential of production of fertilizers from captured fish. Fertilizers produced from captured fish promote the recycling of nutrients from the sea and back to terrestrial environments. Nutritional composition of FW is assessed to determine the potential to supply plant nutrients such as nitrogen, or a combination of nitrogen and phosphorous, or to enrich a compost. Methods used in processing of FW to produce fish- emulsion, fish hydrolysate/fish silage, fish-compost and digestate from anaerobic digestion/co-digestion are presented. Using information about commercially available fish-based fertilizers listed by the Organic Materials Review Institute (OMRI), we present a scenario for establishing fish/ FW-based fertilizers industry and research in Europe. With Norway’s 9th position among top ten global capture producers and focus in Norway on developing organic farming, we brief how FW is currently utilized and regulated, and discuss its availability for possible production of FW-based organic fertilizers. The amount of FW available in Norway for production of fertilizers may facilitate the establishment of an industrial product that can replace the currently common use of dried poultry manure from conventional farming in organic farming.

Wheat (Triticum aestivum L.) is an important cereal crop that provides ample nutritious calories for humans and animals. The nutrient plays a vital role in the production of wheat. In this review, previous works were evaluated to investigate the role of nutrients, nutrient deficiency and toxicity in wheat. Both macro and micronutrients are necessary for wheat plants. Every nutrient has its own character and is involved in different metabolic processes of plant life. Nutrient deficiency and toxicity conditions inhibit normal plant growth and exhibit characteristic symptoms. For optimal growth, development, and production, plants need all the necessary nutrients in balance. A balanced application of the primary nutrients (N, P, K), secondary nutrient (S) and some other micronutrients (Zn, B) are needed to enhance wheat production. The soil tests and the demand for crop nutrients should be assessed to identify the quantity of fertilizer recommended for the crop. This study would be a valuable means to wheat growers and researchers for sustainable and higher wheat production.

Fertilisation in organic agriculture is today highly dependent on the import of external nutrients and organic matter by fertilisers derived from conventional farming and conventional food industries. Within Deliverable (D) 5.1 of the project Organic-PLUS the current use of peat in growing media, plastic for mulching and fertiliser inputs in organic agriculture was already addressed, followed by a report discussing possible alternatives to these contentious inputs (D5.2). The current D5.6 develops the topic further and shows in more detail the results of research on the use of alternative non-contentious fertilisers conducted in Task 5.4, ‘Alternatives to contentious sources of fertility’, of Work package 5 SOIL in Organic-PLUS. The objectives of Task 5.4 were a) to characterise relevant alternatives for contentious inputs for physio-chemical and other characteristics (e.g. availability), and study how well they function compared with existing contentious inputs (manure from conventional farming, commercial fertilisers from conventional sources) and b) to develop system approaches to integrate the alternatives in existing organic cropping systems/ sequences. The characteristics of the individual fertilisers as well as short recommendations for their application in practice are presented in D5.7 (a technical report) along an overview of nutrient concentrations and other essential characteristics of the fertilisers tested.

•Intercropping and strip-cropping appear to farmers as promising systems for replacement of monocultures •The success of intercropping for crop yields and nitrogen use efficiency depends on crop species’ characteristics and control by management. The choices of species and management methods should be knowledge-based •Intercropping and strip-cropping can influence general and functional biodiversity of organisms and the agroecosystem services they provide in a complex way •Alternative fertility strategies based on the combination of a fast and slow releasing source of organic amendments can sustain crop growth, increase short-term soil fertility and promote longterm soil C storage •100% plant-based sources can replace animal-based ones without jeopadizing yields •The combination of intercropping and alternative fertility strategies did not show synergistic effects •Smart automated machinery was completed to solve challenges of mechanization in inter-and strip-cropping systems including a proof-of-concept robotic tool •Successful implementation of inter-/strip-crop systems and fertility strategies relays on detailed insight into the agronomic conditions and agroecological functioning. SureVeg provided such new insight across Europe

Denne rapport indeholder en detaljeret kortlægning af mængden af ​​organisk affald og restprodukter til gødningsformål i Danmark, hentet fra statens databaser.

Prendre soin de son sol passe par une surveillance continue de sa qualité et par des outils qui permettent de diagnostiquer son état et de connaître son fonctionnement avant d’établir les mesures culturales à entreprendre. Discussion autour des risques d'érosion et de compaction ainsi que ces composantes essentielles : vie du sol et matière organique.

Core Organic Cofund project funded in 2018 about new agronomic methods to improve biodiversity and soil fertility in the organic production of vegetables.

• Mikroplast forekommer i restprodukter fra menneskers husholdning, som kan bruges som gødning på marker. Der er mange gode grunde til at genanvende restprodukterne, men tvivl om mikroplasts effekter på jordens fertilitet begrænser genanvendelsen. • Der er mikroplast i organisk husholdningsaffald og spildevandsslam, men et klart og nuanceret billede af indholdet findes ikke. Spildevandsslam indeholder mange små partikler (primært fibre og fragmenter), hvorimod organisk husholdningsaffald indeholder flere større fragmenter (flager fra emballage og poser). Der er indikation på at kompost indeholder flest partikler pr. fosforenhed. • Mikroplast findes i jorden, men der er få studier der har målt koncentrationen på masseenhed. Der findes ikke sammenlignelige data mellem felt- og laboratorieforsøg, ligesom der ikke findes studier der evaluerer massebalancen af mikroplast (og derved nedbrydning), og det er endnu ikke klart i hvilket omfang restprodukter anvendt som gødning bidrager til forurening af jorden sammenlignet med andre kilder (landbrugsplast, henkastning af affald, bearbejdning af jorden mv.). • Forskning inden for mikroplast-effekter i jordmiljøet er et relativt nyt område, hvor de fleste resultater indtil videre er fra laboratorieforsøg. Laboratorieforsøg bruger ofte reducerede systemer, ligesom de ofte bruger højere koncentrationer end man vil forvente at finde i feltforsøg. Det kan give udfordringer i forhold til tolkningen, hvis man forsøger at overføre disse resultater til feltskala. • Det er vist i nogle laboratorieforsøg at mikroplast kan have en effekt på jordlevende organismer. Mange organismer indtager småt mikroplast, hvilket potentielt kan have forskellige negative virkninger på organismen, og kan fungere som første led i bioakkumulering af mikroplast. Der er dog på nuværende tidspunkt ikke konsensus i litteraturen (nogle studier viser negative effekter, mens andre ikke finder effekter af mikroplast), og antallet af effekt-studier foretaget ved miljørealistiske plastkoncentrationer og under miljørealistiske eksponeringsscenarier er stadig begrænset. • Det er observeret at mikroplast tilsat jord i meget høje koncentrationer kan have en negativ effekt på plantevækst, men det antages at det i særlig grad er indirekte effekter, såsom ændret næringsstoftilgængelighed, forandringer i jordstrukturen og dermed jordens evne til at dræne eller tilbageholde vand, samt planters mulighed for at indgå symbioser med organismer som mykorrhiza-svampe og Rhizobium-bakterier. Egentlige strukturelle ændringer af jorden som følge af mikroplastforurening, må antages først at ske ved meget høje mikroplast-koncentrationer. • I laboratoriestudier er det vist at både struktur og funktion af mikrobielle samfund kan påvirkes af eksponering til mikroplast, men generelt undersøges og observeres effekterne ved mikroplast-koncentrationer, som er højere end de koncentrationer der er målt i almindelig landbrugsjord. • Andre fremmedstoffer som organisk forurening og tungmetaller kan adsorberes til mikroplast. Det gør at mikroplast kan fungere som bærer af fremmedstoffer, hvis organismer indtager det, men samtidig kan det også gøre fremmedstoffer mindre tilgængelige for eksempelvis planter og dyr. • CRUCIAL-forsøget er gødet med komposteret husholdningsaffald og spildevandsslam i 20 år, i niveauer som er højere end tilladt (svarende til over 100 års tilførsel). Derfor forventes det at eventuelle skadelige stoffer (mikroplast, tungmetaller, organisk forurening) i produkterne er akkumuleret til et niveau der svarer til, eller er højere end den akkumulering man kunne forvente ved mere end 100 års almindelig gødningspraksis. Det skal bemærkes, at vi endnu ikke har kvantificeret plastindholdet i CRUCIAL jord eller de tilførte gødningsprodukter, men foreløbige pilotanalyser af jord fra CRUCIAL indikerer at der er store forskelle i både plastindhold og plasttype i jord fra de forskellige gødningsbehandlinger. Vi har ikke fundet skadelige virkninger af tilførte affaldsprodukter på regnormesamfund, potentialet for kvælstoffiksering eller jordens fødenet. • Tilførslen af spildevandsslam og komposteret husholdningsaffald i CRUCIAL-forsøget har fremmet jordens sundhed, hvad angår mikroorganismer, dyr og planters trivsel sammenlignet med ugødet jord. Produkterne har bidraget til et højere indhold af organisk stof i jorderne, og fungeret som næring, samtidigt med at der ikke er fundet indikationer på utilsigtede virkninger af en cocktail af uønskede stoffer, herunder mikroplast, tungmetaller og organiske fremmedstoffer, vi antager er tilført med særligt de organiske gødningsprodukter over årene. • I fremtidige studier bør der især fokuseres på at inkludere felt- og storskala model-økosystem-forsøg. For at kunne sammenligne forskellige studier er det nødvendigt at standardisere metoder til prøvetagning og måling af koncentrationen af mikroplast i gødning og jord. Desuden er det vigtigt at undersøge effekten af mikroplast på jordlevende organismer i felten eller i terrestriske model-økosystemer.

Øget opmærksomhed på jordfrugtbarhed fører til øget brug af mere detaljerede og specifikke metoder til at analysere jord og planter. Standardjordprøver med Rt, Pt, Kt og Mg bliver i stor stil anvendt som styringsredskab i økologiske marker. I RDD 8-projektet Fertihood har Innovationscenter for Økologisk Landbrug undersøgt rådgiveres brug af jordprøver og andre metoder til at vurdere jord og afgrøder. Resultaterne af spørgeskemaundersøgelsen fremgår af dette skrift.

The objective of the SureVeg project was to develop and implement new diversified, intensive organic vegetable cropping systems. This included the use of inter- and strip-cropping and fertility strategies based on soil improvers and fertilizers from either plant or animal origin, compared to monocropping systems and commonly used animal based fertilizers in organically managed cropping systems. We found that • Intercropping and strip-cropping appear to farmers as promising systems for replacement of monocultures, but they ask for better comprehension of the systems in practice, e.g. on good companion crops and step-by-step guidelines. • A method has been developed for mining the scientific literature on good companion crops that will enable uncovering crop-crop effects as well as crops that have remained under-investigated compared to their on-farm use. • The succes of intercropping for crop yields and nitrogen use efficiency depends on crop species’ characteristics (complementary instead of competing) and control by management (e.g. displacement of sowing/planting time). Therefore the choices of species and management, when designing intercropping systems, are crucial and should be knowledge-based. • Intercropping and strip-cropping can influence general and functional biodiversity of organisms and the agro ecosystem services they provide (natural biological control, pollination, soil health and fertility; above and belowground) in a complex way that interplays with factors, such as annual differences in agronomic conditions and crop choices. E.g. intercropping may increase mycorrhization and decrease soil pathogenic bacteria and fungi compared to mono-cropping. While diversity of ground dwelling carabids has been found to go up, some species decrease in abundance compared to monocultures. • Alternative fertility strategies based on the combination of a fast and slow releasing source of organic amendments can sustain crop growth, increase short-term soil fertility and might promote soil carbon storage in the long-term. The combination of organic amendments (the quality) is crucial, and 100% plant-based sources can replace animal-based ones without jeopadizing yields. • The combination of intercropping and alternative fertility strategies did not show synergistic effects. • The creation of smart automated machinery was completed to solve challenges of mechanization in inter- and strip-cropping systems including a proof-of-concept robotic tool, sensing and actuation, to apply single-plant fertilizer strategies. The robot including sensors etc. was built and algorithms developed e.g. to calculate single plant volume and vegetation indexes, and the robot was successfully demonstrated. Overall a successful implementation of intercropping/strip-cropping systems and fertility strategies with beneficial impact on crop production, soil and environment of intercropping/strip-cropping systems and fertility strategies relays on detailed insight into the agronomic conditions and agroecological functioning in the production of organic vegetables. The SureVeg provides such new insight across Eurpean conditions from transnational research; insight that has been disseminated to stakeholders at many levels during the project.

Præsentation af en række emner i relation til gødningsanvendelse på økologiske brug, herunder: • Sædskifte • Nye regler • Hvor bruger I N? • Krav om bælgplanter • Kulstofpositiv markplan • Biogasgylle • ”Nye” næringsstoffer • Efterafgrøder • Pligtige • Frivillige

Seminar for Danish Agricultural academia union

Seminar given to the vegetable consultants from the advisory company HortiAdvice

Ud over de pligtige efterafgrøder, som nu også kan indeholde bælgplanter, vil en etablering af ekstra frivillige efterafgrøder kunne gavne klima og miljø, yderligere. Hovedformålet med at etablere efterafgrøder i marken, er at mindske udvaskningen af næringsstoffer og dermed mindske næringsstofforurening af vandmiljøet. Efterafgrøder er dog ikke kun godt for at mindske udvaskningen, de har også en effekt på klimaet. Udvaskningen af kvælstof giver en indirekte udledning af lattergas, som er en meget potent drivhusgas. Når udvaskningen mindskes, mindskes den indirekte udledning af lattergas fra denne kilde dermed også. Den indirekte lattergas emission opstår når nitratkvælstof i vandmiljøet efterhånden omdannes til lattergas