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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 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

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. Deficient 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 deficits and lower outputs. We show, for the first 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 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

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.

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

Experiments showed higher N efficiencies for stored human urine, digestates and sewage sludge than compost. Additionally, higher contents of ammonium-nitrogen (NH4+-N) and a lower C/N ratio increase the nitrogen efficiency of recycled fertilisers.

Reducing soil tillage can lead to many benefits, but this practice often increases weed abundance and thus the need for herbicides, especially during the transition phase from inversion tillage to non-inversion tillage. We evaluated if subsidiary crops (SCs, e.g., cover crops) can mitigate the effects of non-inversion tillage on weed abundance. Two-year experiments studying SC use, tillage intensity, and nitrogen (N) fertilization level were carried out twice at six sites throughout northern and central Europe. SCs significantly reduced weed cover throughout the intercrop period (−55% to −1% depending on site), but only slightly during the main crops. Overall weed abundance and weed biomass were higher when using non-inversion tillage with SCs compared to inversion tillage without SCs. The effects differed due to site-specific weed pressure and management. With increasing weed pressure, the effect of SCs decreased, and the advantage of inversion over non-inversion tillage increased. N fertilization level did not affect weed abundance. The results suggest that SCs can contribute by controlling weeds but cannot fully compensate for reduced weed control of non-inversion tillage in the transition phase. Using non-inversion tillage together with SCs is primarily recommended in low weed pressure environments.

Figurative language can be approached in several ways. This essay examines the use of similes in Charlotte Brontë’s Jane Eyre. All similes in the novel were collected and divided into categories based on the vehicle used. The largest categories that I have identified, I have termed “Nature and its forces”, “Concrete objects” and “Abstractions”. The similes are further divided into sub-categories by the construction of the simile, ranging from simple to complex. Furthermore, similes in emotional passages are analysed and discussed. I argue that there is a simile in connection to all emotional passages in the novel. In addition, I claim that the similes used in emotional situations are more complex. Hence they function to make the language more, intense, concrete and clear. All similes are stated in the Appendix.