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Bern, Switzerland

After organic farming arose as a chain separate from conventional food production in many parts of the world in the last quarter of the 20th century, another separate chain emerged in recent years-the chain for food free of genetically modified organisms (GMOs). This article summarizes the lessons learned from segregated organic chains and compares them with new findings gathered from GMO-free chains of soybeans, maize, and milk in Western Europe. Two mechanisms are found to be widespread to cope with the transaction costs of segregation: a specialization of businesses or entire countries and a "downwashing" process, during which a sequence with decreasing quality requirements is used in facilities. The main role of the state is to create a framework that provides a high degree of credibility for the product information provided. © 2015 AgBioForum.

Pornaro C.,University of Padua | Schneider M.K.,Agroscope | Macolino S.,University of Padua
Biological Conservation | Year: 2013

Cessation of agricultural management and subsequent natural forest succession has been the primary land use change in the Southern Alps over the past 50. years. It is generally assumed that early stages of succession host more plant species than grazed pastures, but that this richness is partly lost as the density of woody species increases. Based on vegetation surveys on eight sites in the Italian Alps, we found the effects of forest succession on plant species richness to depend strongly on environmental conditions. The relationship between plant species richness and wood cover at the sites ranged from non-detectable over hump-shaped, to monotonically decreasing. Linear mixed-effects models indicate that high mean annual temperature is associated with a strong decrease in plant species richness and in the number of red-list species along the pasture-to-forest gradient. Sampling plant species composition at a range of scales allowed us to rule out artefacts caused by modified species-area relationships as a consequence of changes in wood cover. Multi-scale sampling also indicated that the primary loss of plant species richness by forest succession is in plant species with low abundance. Our data further allow assessment of the risk of species loss in mountain grasslands in the Southern Alps, which is highest on sites with higher mean annual temperature. These areas should receive concentrated attention and support for biodiversity conservation. © 2013 Elsevier Ltd.

News Article
Site: phys.org

Food waste is today's hot topic. In fact, according to scientific surveys in Switzerland, 300 kg of perfectly good food ends up in the bin per person each year. However, this number encompasses the entire shopping basket, from yoghurt to drinkable leftover wine and two-day-old bread. From this basket, scientists at the research institute Agroscope and ETH Zurich have now identified one product that is discarded disproportionately often: the potato. A new study on this topic has just been presented by ETH doctoral student Christian Willersinn, who works in the group led by Michael Siegrist, Professor of Consumer Behaviour, together with colleagues from Agroscope. The study breaks down the losses of this staple food along the entire supply chain. "With this study, we aim to deepen the discussion relating to food waste by looking at a single product," says lead author Willersinn. The study appeared in the journal Waste Management. Until now, precise figures on potato waste were only available from England, where around two thirds of potatoes end up in the bin. However, Willersinn says that these figures cannot be compared with the situation in Switzerland. For the Swiss study, the researchers from Agroscope and ETH examined the losses that occur at the producer, wholesaler, retailer, processor and consumer level. The researchers recorded the quantities both of table potatoes and of processing potatoes, which are processed into chips and crisps. They also compared the losses that occur in organically and non-organically produced potatoes in both categories. To ascertain the quantities lost at the producer stage, Willersinn and his colleagues used data from more than 220,000 quality assessments of individual tubers. The researchers also surveyed wholesalers and retailers in order to obtain the most accurate quantitative information possible at that level. Furthermore, they carried out a written survey of 2,000 households to collect data on private potato waste. In addition to this, 87 people kept a diary for 30 days, in which they recorded their exact potato consumption and exactly how much of the originally purchased quantity, including preparation waste, ended up in their bins. One in two potatoes thrown out "Overall, potato waste is also very high in Switzerland," says the ETH doctoral student in light of the results of his analyses. From the field to the home, 53 percent of conventionally produced table potatoes are wasted, and this figure rises to 55 percent for those produced organically. For processing potatoes, the figures are lower: 41 percent of organic potatoes are discarded, compared to 46 percent of those from conventional production. The higher waste proportion for conventionally farmed processing potatoes is connected to the overproduction of this crop, which barely ever occurs with organic farming. Waste is greater for organically farmed table potatoes because these fail to satisfy the high quality standards more often than conventional ones. "After all, consumers have the same expectations of quality and appearance for organic production as they do for conventional." Losses occur at all stages of the supply chain: up to a quarter of the table potato harvest falls by the wayside even at the producer stage. A further 12 to 24 percent are rejected by wholesalers during sorting. Just one to three percent fall between the cracks at retailers, and a further 15 percent are wasted in households. Although private households account for a relatively small proportion of potato waste, Willersinn says their contribution has the most impact: in private homes, most of the unused potatoes end up in the bin bag or on the compost heap. Producers, traders and processors, on the other hand, recycle the vast majority of waste into animal fodder or, to a lesser extent, into feedstock for biogas plants. According to Willersinn, the blame lies primarily with consumers' high quality standards, especially when it comes to fresh potatoes. This accounts for two thirds of the waste in respect of fresh potatoes from conventional farming. For organic potatoes, this figure rises to three quarters. Consumer health protection also leads to waste: producers reject one in three potatoes after harvest because they are rotten or green and could therefore be harmful to health. Wireworms, i.e. the larvae of click beetles, have also eaten holes into many potatoes, although they would still be edible. Likewise, misshapen or deformed potatoes would be edible but, just like 'worm-eaten' potatoes, are fed to animals for aesthetic reasons. In order to reduce potato waste, therefore, the researcher suggests taking action on the producer side first and foremost; for example, by using suitable cultivation methods such as crop rotation to minimise infestation, by protecting plants against wireworms, and by breeding new, more-robust varieties of potatoes. He is certain: "These measures could improve quality and therefore result in less waste". Shrinking the mountain of waste would also require revised quality requirements, so that misshapen or scabby potatoes could make it onto the shelves. This could reduce losses of conventional fresh potatoes by four percent and organic table potatoes by three percent. However, he says that wholesalers and retailers take a critical view of scabby potatoes, as scab can be transmitted to healthy specimens. "This would mean that waste would occur at the end-consumer stage, instead of at the producer and trader level, because consumers have different quality expectations," Willersinn adds emphatically. He says the eco-balance is at its worst when consumers throw potatoes in the bin. "Losses at the end of the chain are the worst because, at this stage, the most energy has been put into the product. The most sensible thing is therefore to minimise household waste," Willersinn emphasises. He adds that a corresponding study is currently in progress. The ETH doctoral student and Agroscope staff member places the principal onus on consumers: they need to reconsider their preferences and their buying and eating habits. "However, habits are very difficult to change," he emphasises, noting that, according to the household survey, older people throw out less than young people. Willersinn can only speculate on the reasons for this. It is conceivable to him that older people know how to store potatoes and that young people, on the other hand, lack some of this knowledge. This study was carried out as part of the National Research Programme NRP69, "Healthy Nutrition and Sustainable Food Production", funded by the Swiss National Science Foundation (SNSF). It is the most extensive study ever produced in Switzerland on the topic of food waste in respect of a single product. Explore further: Gene expression reveals how potatoes are cultivated More information: Christian Willersinn et al. Quantity and quality of food losses along the Swiss potato supply chain: Stepwise investigation and the influence of quality standards on losses, Waste Management (2015). DOI: 10.1016/j.wasman.2015.08.033

Naderi-Boldaji M.,Shahrekord University | Keller T.,Agroscope | Keller T.,Swedish University of Agricultural Sciences
Soil and Tillage Research | Year: 2016

The soil physical parameter S (S-value or S-index) has been proposed as an index of soil physical quality. Soil physical quality is negatively affected by soil compaction (e.g. caused by agricultural field traffic). It has previously been shown that S decreases with increasing soil bulk density. This study investigated whether the relationship between S and soil compactness can be described by a single function that is valid across soil textures when soil compactness is expressed in terms of the degree of compactness (DC), which is relative density expressed as the ratio of bulk density to a reference density. This would provide an alternative measurement for soil physical quality that is more easily obtained than S. We also evaluated different methods for deriving reference density and tested whether reference values for S suggested in previous studies correspond to critical levels of DC reported in the literature. The relationships between S and DC were investigated for the 12 FAO/USDA soil textural classes based on pedo-transfer functions, and compared with data reported in the literature. A strong positive correlation was found between DC and ln (1/S), and a unique function was found between S and DC that is valid across soil textures, with the possible exception of poorly sorted soils with a high sand or silt concentration. Experimental data on S obtained from the literature supported these findings. The reference value of S (0.035) previously proposed as a boundary between good and poor soil physical conditions was found to agree well with the level of DC (87%) reported in the literature as critical with respect to plant growth. Proctor density was found to be the most useful measure of reference density, better than Håkansson reference density, which introduced some texture dependency into the relationship between S and DC. Our findings indicate that 1/S is a good measure of soil compactness and support the usefulness of S as a soil physical quality index. However, our findings suggest that DC can also be used as an index of soil physical quality, and is much easier to obtain than S. © 2016 Elsevier B.V.

Naderi-Boldaji M.,Shahrekord University | Weisskopf P.,Agroscope | Stettler M.,Bern University of Applied Sciences | Keller T.,Agroscope | Keller T.,Swedish University of Agricultural Sciences
Soil and Tillage Research | Year: 2016

This study sought to develop empirical models to predict soil relative density (ρrel) from measurements of horizontal penetrometer resistance (PR) and soil water content (θg) in a wide range of soil textures. This permits the comparison of the state of soil compactness in different soil textures. It was hypothesised that model coefficients would be texture-dependent when soil compactness was expressed as bulk density (ρd) and that a model with constant coefficients could be obtained when soil compactness was expressed in terms of ρrel (obtained as the ratio of ρd to reference bulk density (ρref)). Field measurements were conducted in 2014 using a horizontal penetrometer at 0.25 m depth in 10 fields in Switzerland with a wide range of soil textures covering sandy loam, silt loam, loam, clay loam and clay (clay concentration, (CC) = 153-585 g kg-1 and organic matter concentration, (OM) = 9-168 g kg-1). At selected locations along the penetrometer measurement transects, cylindrical soil cores were sampled for determination of soil texture, OM, θg and ρd. Soil water potential and effective stress (σ') were also estimated for each location. Standard Proctor tests were performed on eight soils with variable textures. Proctor density was well described as a function of CC and OM (R2 adj = 0.97, RMSE = 0.046 Mg m-3) and was used as reference density to obtain ρrel. From this we developed a model for prediction of ρrel from PR and σ' that allows comparisons between soils without changes in model coefficients. However, σ' cannot be obtained from on-the-go measurements and the model is therefore of limited value for soil compaction mapping. A model for estimating ρrel from PR and θg yielded satisfactory predictions (R2 adj = 0.66, RMSE = 3.3%), although θg is a texture-dependent measure of soil water that cannot be compared across soils. Moreover, ρd was well predicted from PR and θg (R2 adj = 0.93, RMSE = 0.05 Mg m-3), possibly because all our measurements were carried out at similar soil water potential, which implies that θg carries soil textural information. Future research should test the proposed equations for a wide range of soil water potential values. The findings presented can be of use in developing measurement systems for mapping soil compactness that combine the proposed prediction functions with horizontal penetrometer and water content sensor systems. © 2015 Elsevier B.V.

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