| 1. |
- Aronsson, Helena, et al.
(författare)
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Phosphorus load in outdoor areas for laying hens and capacity of phosphorus retaining materials to reduce the environmental impact
- 2022
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Ingår i: Organic Agriculture. - : Springer Science and Business Media B.V.. - 1879-4238 .- 1879-4246. ; 12:3, s. 325-
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated manure loads in outdoor paddocks for laying hens and the capacity of two phosphorus (P) retaining materials for reducing leaching from manure in areas with high hen density. Inventories on two commercial farms during 2 years (2017 and 2018) of the impact of hens (groups of 3000 hens) on vegetation, as a proxy for land use by hens, showed that 16–21% of outdoor area in grassland paddocks and 22–39% of area in a forest paddock were used by the hens. Sand and limestone were tested as P retention materials in areas with high manure load in a field study during the outdoor season for laying hens (May 1 to October 31 in 2018). The materials were placed on the ground (0.2 m deep bed, 3.3 m wide) outside the pop-hole in paddocks with 76 hens. The average numbers of hens outdoors were recorded at 9 am and 3 pm daily. There was no significant difference between the materials concerning distribution of hens, and they seemed not to prefer any material more than the other. When cylinders containing the spent materials were exposed to simulated rainfalls in a laboratory study, the P concentrations in drainage water were high for all materials, including a control with gravel (58–136 mg PO4-P L−1 and 130–197 mg total-P L−1). On average, 14% of manure P retained in the sand and limestone materials was leached after 100 mm of simulated rainfall. Thus, these materials may act as physical filters for P in manure, but to reduce the risk of P losses to waters during the following winter, they need to be removed from the paddocks and preferably used as potential P fertilizers on arable land. © 2021, The Author(s).
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| 2. |
- Denver, Sigrid, et al.
(författare)
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Dietary priorities and consumers’ views of the healthiness of organic food : purity or flexibility?
- 2022
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Ingår i: Organic Agriculture. - : Springer Science and Business Media LLC. - 1879-4238 .- 1879-4246. ; 12:2, s. 163-175
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Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown that belief in the healthiness of organic food is a strong motive for buying organic. Typically, a positive relation between a nutritionally balanced diet (with respect to fruit, vegetables and meat) and organic consumption is also found. As market shares of organic food are much smaller than those of conventional food, consumers may face a trade-off between buying organic and choosing the nutritional composition they prefer. Using data from a survey of around 1300 Danish consumers, we found that almost all respondents believed that organic food contains fewer unwanted substances than non-organic food, and that around a third considered organic food to be nutritionally superior. Respondents with high organic consumption and who believe in the nutritious superiority of organic food products were more likely to belong to a small group of respondents who prioritized buying organic. However, the vast majority, particularly those with low levels of organic consumption, prioritized dietary flexibility over organic produce. Our findings suggest that to motivate those in this large consumer segment to increase their organic consumption, it will be necessary to offer a broader, more nutritionally differentiated, range of organic products.
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| 3. |
- Lindgren, Kristina, et al.
(författare)
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Nematode parasite eggs in pasture soils and pigs on organic farms in Sweden
- 2020
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Ingår i: Organic Agriculture. - : Springer. - 1879-4238 .- 1879-4246. ; 10, s. 289-300
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Tidskriftsartikel (refereegranskat)abstract
- The EU regulation for organic pig production requires outdoor access to promote the animal welfare. This may increase the risk of infection of the common pig parasites, Ascaris suum and Trichuris suis, because their eggs can survive for many years in the soil. The egg contamination of these parasites in outdoor areas with different managements and the faecal egg output from the pigs was investigated on 11 Swedish organic pig farms in 2008. We found eggs of A. suum and, to a minor extent, T. suis in the soil from outdoor areas, which had previously been used for pig rearing and/or for spreading of pig manure. Piglets and their dams were turned out on pastures included in a crop rotation, and these areas had a mean of 2500 A. suum and 40 T. suis eggs per kilogram soil. When the pigs were 12-week-old, the faecal egg counts (FECs) of A. suum were positively correlated with the egg concentration in pasture soils before pig turnout. The areas used by dry sows had a mean of 11,700 A. suum and 220 T. suis eggs per kilogram soil. The highest egg concentrations in the soil were found in areas, frequently used by pigs in the most recent years. To minimise pasture contamination with parasite eggs, it is advised to have a crop rotation system and to inactivate parasite eggs in pig manure before spreading it. Parasite control needs further development to protect suckling piglets from infections due to environmental parasite egg contamination. © 2019, The Author(s).
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| 4. |
- Milestad, Rebecka, 1973-, et al.
(författare)
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Tensions in future development of organic production—views of stakeholders on Organic 3.0
- 2020
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Ingår i: Organic Agriculture. - : Springer. - 1879-4238 .- 1879-4246.
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Tidskriftsartikel (refereegranskat)abstract
- This study analysed Swedish stakeholders’ views on future developments of organic production and consumption based on Organic 3.0, a strategic initiative by the International Federation of Organic Agriculture Movements (IFOAM). Focus group discussions were carried out with actors representing different parts of the organic value chain in Sweden. These identified a number of tensions, four of which represented an unresolved dichotomy in the way forward for the organic movement and its relevance for organic production in most settings. The first tension was between the drive for increased efficiency to achieve higher yields and an agroecological approach with broader sustainability values. The second concerned availability of plant nutrients in organic agriculture including safe recirculating of nutrients from society. The third tension set new technology against the precautionary principle and the notion of naturalness. The fourth concerned the role of organic as an innovation system; whether organic should be a forerunner, i.e. performing well above average and fostering innovation, or whether organic should be a broader movement including more farmers but then requiring more regulations that may hinder innovation. These tensions will result in important choices on direction for the organic sector as it pursues the Organic 3.0 goal of sustainably feeding a growing population based on farming systems based on organic principles.
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| 5. |
- Salomon, Eva, et al.
(författare)
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Flows and budgets of nutrients and potentially toxic elements on four Swedish organic farms using digestate from agricultural residues
- 2022
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Ingår i: Organic Agriculture. - : Springer Science and Business Media LLC. - 1879-4238 .- 1879-4246. ; 12:2, s. 279-292
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Tidskriftsartikel (refereegranskat)abstract
- Few fertilizers are permitted for organic farming, which is a challenge when securing nutrient availability, particularly of nitrogen (N). Digestate from biogas production could be a valuable fertilizer for increasing crop yields, through its high content of plant-available nitrogen (NH4-N), but is rarely used in practice. This study evaluated how anaerobic digestion of manure and use of digestate affected inflows and outflows of nutrients and potentially toxic elements on four organic farms with different solutions for digestate production. Mass flows and element concentrations were documented 3 years on three dairy farms and one crop farm and used for calculating farm budgets. Nitrogen and phosphorus (P) budgets were also calculated for biogas reactor and storage pits on three farms. Nitrogen surplus exhibited large variation (18–87 kg N ha−1 year−1) at farm level, with purchased digestate or poultry manure giving major N inputs. The risk of process losses was high, with up to 40% of N and P in feedstock entering farm biogas reactors not recovered in digestate. The proportion of NH4-N in total N in digestate was slightly higher (2–9%) or lower (37%) than in feedstocks entering farm biogas reactors. Improved stirring in farm biogas reactors and storage pits to decrease N and P sedimentation, particularly when digesting poultry manure, would directly increase digestate value. Two farms purchasing digestate from central biogas plants received a digestate causing significant cadmium inputs. Keeping records on element flows can help to tailor the use of digestate for organic farms to achieve a sustainable use of nutrients.
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| 6. |
- Wallenbeck, Anna, et al.
(författare)
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Leg health, growth and carcass characteristics in growing-finishing pigs of two different genotypes reared on Swedish organic farms
- 2020
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Ingår i: Organic Agriculture. - : Springer Science and Business Media LLC. - 1879-4238 .- 1879-4246. ; 10, s. 97-103
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Tidskriftsartikel (refereegranskat)abstract
- Increased prevalence of joint abnormalities at slaughter among pigs from organically certified herds in Sweden has been reported. Most of these abnormalities are caused by osteochondrosis, which has a genetic background. Thus, we investigated whether changing the sire breed from the commonly used Hampshire to the commercially available sire breed Duroc affected joint health and growth rate. We studied 766 commercially reared growing-finishing pigs from insemination of the mother sow until slaughter. The pigs were raised at four commercial organic farms (integrated or externally integrated, and had 40–160 sows in production)and slaughtered at one slaughter plant. We found no significant difference between the offspring of the two sire breeds regarding back conformation, leg conformation, swollen joints, locomotion or lameness at 13 or 24 weeks of age, or regarding joint abnormalities at slaughter. This indicates that clinical leg health will not be improved by changing sire breed. However, the Hampshire-sired pigs had higher daily growth rate(P< 0.008), allowing earlier slaughter.
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| 7. |
- Wivstad, Maria, et al.
(författare)
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Survey of farm-gate N and P balances on arable and dairy organic and conventional farms in Sweden—basis for improved management
- 2023
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Ingår i: Organic Agriculture. - 1879-4238 .- 1879-4246. ; 13:3, s. 411-
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Tidskriftsartikel (refereegranskat)abstract
- About half of all N and P loads to Swedish waters originate from agriculture and must decrease to reach environmental goals. Studying nutrient management at farm level can provide an understanding of nutrient recycling and the risk of losses. In a survey of organic and conventional dairy and arable farms in three southern counties of Sweden, farm-gate N and P balances and N use efficiency (NUE) were analysed. Crop distribution differed significantly between organic and conventional farms, with organic dairy farms having higher proportions of ley and pulse crops and organic arable farms having a much higher proportion of N-fixing crops than corresponding conventional farms. Conventional dairy and arable farms had on average 70% and 40% higher N surplus than corresponding organic farms. Farm-gate P surplus was larger on conventional dairy farms and much larger on organic arable farms, mainly due to purchase of P-rich organic fertilisers. Organic dairy farms had higher NUE than corresponding conventional farms, but the opposite was true for arable farms. However, in the southernmost county Skåne, where soil fertility and yield potential are high, NUE was similar on all arable farms. Total inputs of N and P were positively correlated with N and P surpluses, especially on dairy farms. Improved manure and crop residue management, reduced use of purchased mineral N fertilisers coupled to more uniform within-farm distribution of manure, use of catch crops, intercropping and organic fertilisers with appropriate N:P ratio are measures that can reduce farm nutrient surpluses and improve nutrient management on both organic and conventional farms.
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| 8. |
- Åkerfeldt, Magdalena, et al.
(författare)
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Health and welfare in organic livestock production systems—a systematic mapping of current knowledge
- 2021
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Ingår i: Organic Agriculture. - : Springer Science and Business Media LLC. - 1879-4238 .- 1879-4246. ; 11, s. 105-132
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Forskningsöversikt (refereegranskat)abstract
- This review aimed to systematically map and summarize the status of animal health and welfare in organic production. The prevalence of diseases and behavioural effects in organic dairy cow, beef cattle, sheep, pig, laying hen and broiler chicken were discussed in the context of the organic values and current knowledge on animal health and welfare. In total 166 peer-reviewed scientific publications between 2008 and 2020 were included. No strong evidence for neither inferior nor distinctly higher animal welfare in organic compared with conventional production could be supported. The welfare status of organic livestock is in general good in relation to the OIE definition of animal health and welfare. However, organic systems are still facing several challenges related to animal health and the arising of goal conflicts due to management and practical implications. Greater possibilities to perform species-specific behaviours in organic production systems, however, indicate that the organic standards offer a good framework for high animal welfare management. For organic dairy farmers, the main health problems are similar to those of non-organic farms; especially mastitis and lameness need improvement. Parasites, together with mastitis and lamb mortality, are important welfare issues in organic sheep production. Piglet mortality, leg problems, parasite load and increasing respiratory problems are of major relevance in organic pig production. For organic laying hens, major health challenges relate to feather pecking and cannibalism, parasites and possibilities to express species-specific behaviours. For organic broilers, dermatitis of footpads, hocks and breast are reported as main health issues.
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| 9. |
- Asp, Håkan, et al.
(författare)
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Nutrient utilization and growth of tomato crops fertilized with solid anaerobic digestate
- 2024
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Ingår i: Scientia Horticulturae. - 0304-4238 .- 1879-1018. ; 329
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Tidskriftsartikel (refereegranskat)abstract
- Anaerobic digestate is a valuable resource for horticultural production, as it contains nutrients and fibers that can be used in plant growing medium. However, compared with hydroponic production based on mineral fertilizers, obtaining accurate nutrient supply at each stage of the growth cycle may be challenging. In an experiment using container-grown tomato crops, we evaluated different fertilization regimes with solid anaerobic digestate (SAD). Four different treatments were compared, two involving different proportions (19 % and 37 % by volume) of SADs in the peat-based growing medium, one treatment where growing medium with 37 % SAD was inoculated with active nitrifying bacteria, and one treatment where 15 % (v/v) of the peat in growing medium with 37 % SAD was replaced with sawdust to control nitrogen (N) availability during cultivation. A mineral-fertilized treatment (N-P-K 5–1-5) with approximately similar N amount as in the treatment with 37 % SAD was used as reference. Nutrient availability, nutrient uptake efficiency, crop performance (plant growth, biomass accumulation), and plant stress (chlorophyll fluorescence) were monitored during cultivation. The concentration of ammonium was initially high (190–416 mg/L substrate) in the growing media fertilized with anaerobic digestate, while the concentration of nitrate was low. Readily available ammonium concentration decreased rapidly during cultivation, to around 50 % after 10 days and to almost 100 % by the end of the cultivation. Available nitrate concentration was initially low (0–8 mg/L in the different treatments) and decreased to zero within a week, but increased slightly from day 40 of cultivation. Nutrient use efficiency was generally higher (15–50 % for different nutrients) in the treatment with 19 % digestate. Inclusion of sawdust in the growing medium decreased nutrient use efficiency by 30–50 %. Compared with the mineral-fertilizer reference, biomass production was lower in all treatments fertilized with digestate, with 37 % and 19 % SAD resulting in 62 % and 47 % of total biomass obtained in the reference, and similar reductions in yield of harvestable fruits. Chlorophyll fluorescence measurements indicated elevated plant stress in the treatments fertilized with SAD. Addition of sawdust or nitrifying bacteria did not help to control nitrogen availability during cultivation. Therefore, anaerobic digestate fertilizers need further optimization before they can be a competitive alternative to mineral fertilizers.
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| 10. |
- Bergstrand, Karl-Johan
(författare)
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Organic fertilizers in greenhouse production systems - a review
- 2022
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Ingår i: Scientia Horticulturae. - : Elsevier BV. - 0304-4238 .- 1879-1018. ; 295
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Forskningsöversikt (refereegranskat)abstract
- From a sustainability point of view, there are strong arguments of nutrient recycling within the society, which means more use of organic nutrient sources within agriculture and horticulture. At the same time, there is an increasing consumer demand for certified organic products, and incentives from governments to increase the conversion of production areas to organic production. This also applies to greenhouse horticulture. Many different raw materials for organic fertilizers are used as of today, such as animal manures, slaughterhouse byproducts, vegetable byproducts, green manure, algae, composts, anaerobic digestates etc. In common for all these fertilizer types is that they are limited in availability, not always consistent with respect to nutrient content, and that they require microbial degradation in order to mineralize its content of nutrients, and are thereby more or less to be characterized as slow release fertilizers. Greenhouse horticulture is different from open field agriculture in several ways with respect to nutrient supply. Firstly, the use of fallow crops and crop rotation is not practical due to the high investment costs bound in the greenhouse structure. Secondly, growth per unit area is significantly higher than in outdoor production, with subsequently higher nutrient demand, often concentrated to a relatively short period of time. On the other hand, climatic factors such as soil temperature and moisture can be controlled which is beneficial for the control of nutrient release. Traditionally, animal by-products such as manure and slaughterhouse wastes have been widely used as organic fertilizers. However, limited availability and ethical concerns is currently driving forces in the search for alternative nutrient sources. The use of solid and liquid anaerobic digestates as fertilizers is a promising practice for greenhouse horticulture. Energy is a “by product” from the production and the nutrient content of the digestates can be modified by feeding the anaerobic reactor with different stock. Furthermore, it is suggested that techniques for fine-tuning the nutrient supply in organic greenhouse horticulture is further developed and adopted, such as the use of microbial biofertilizers and foliar sprays.
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