Chongtham I.R.,Swedish University of Agricultural Sciences |
Bergkvist G.,Swedish University of Agricultural Sciences |
Watson C.A.,Swedish University of Agricultural Sciences |
Watson C.A.,Scotlands Rural College Sruc |
And 4 more authors.
Biological Agriculture and Horticulture | Year: 2016
Productive crop rotations are central to the success of organic production systems. The selection and sequence of crops are determined by a combination of agronomic and economic factors as well as the principles and standards of organic farming. Semi-structured interviews were conducted with sixteen organic farmers in Central-east Sweden to explore the factors that influence the design of crop rotations and the trade-offs between these factors, taking into account the length of time since conversion to organic production. We discerned three crop rotation strategies: strict, flexible and liberal, based on how crop(s) are repeated over time. A major trade-off for arable farmers was between perennial leys to provide nitrogen and control weeds, and the use of more inputs such as purchased nutrients and mechanical weed control to allow continuous cereal production. Critical considerations for livestock farmers were the length of ley for feed production and weed control, cost of re-seeding leys and decisions about whether to grow crops to feed animals or cereals to sell. Farmers practicing organic for a long time (more than 10 years) often had flexible rotations to adapt to changing conditions, but they generally included leys and a selection of annual crops in line with the principles of crop rotation and organic farming. Recently converted organic farmers usually concentrated on controlling weeds and producing sufficient livestock feed by following strict crop rotations. We conclude that farm type and experience strongly influenced rotation strategies and that weed management and market prices were the most important influences. © 2016 Informa UK Limited, trading as Taylor & Francis Group
Chalmers N.G.,University of Edinburgh |
Brander M.,University of Edinburgh |
Revoredo-Giha C.,Scotlands Rural College Sruc
International Journal of Life Cycle Assessment | Year: 2015
Purpose: There is an apparent convention within both consequential and attributional life cycle assessment (LCA) to assume a 1:1 substitution ratio between functionally equivalent product systems. However, this convention may not be compatible with the purpose of consequential LCA, which is to model the actual consequences of the decision at hand. This paper explores the implications of the convention using the illustrative example of a 1 % tax on whole milk. Methods: A consequential LCA which assumes a 1:1 substitution ratio between two functionally equivalent product systems is compared with the results of an analysis that estimates the actual substitution ratio based on empirical data. Cross-price elasticities of demand for possible competitor products are modelled using a linear approximated almost ideal demand system (LA-AIDS). Results and discussion: The results show a 1:0.52 substitution ratio between whole and low fat milk, rather than a 1:1 substitution ratio. Depending on the consequential LCA values for whole and low fat milk, the 1:1 convention could underestimate the greenhouse gas emission reductions from the tax by over 400 %. Conclusions: The results suggest that it is highly important to model actual substitution ratios between competing product systems in order to capture the consequences of the decision at hand. As a subsidiary contribution, the paper also shows the importance of modelling the displacement effects of milk fat co-products, which are generally not considered in the existing LCA literature on milk. © 2015, The Author(s).
Oliver D.M.,University of Stirling |
Hanley N.D.,University of St. Andrews |
van Niekerk M.,University of Stirling |
Kay D.,Aberystwyth University |
And 23 more authors.
Ambio | Year: 2016
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations. © 2015, The Author(s).
Zander P.,Leibniz Center for Agricultural Landscape Research |
Amjath-Babu T.S.,Leibniz Center for Agricultural Landscape Research |
Preissel S.,Leibniz Center for Agricultural Landscape Research |
Reckling M.,Leibniz Center for Agricultural Landscape Research |
And 11 more authors.
Agronomy for Sustainable Development | Year: 2016
Sustainable development of agriculture is at the core of agricultural policy debates in Europe. There is a consensus that diversification of cropping would support sustainable development. However, a reduction in legume cultivation has been observed in the EU during the last decades. This decline has induced, in turn, a deficit of proteins and a reduction of ecosystem services provided by legumes. Therefore, we analysed the mechanisms that shape agricultural systems to identify leverage points for reviving European legume production. Specifically, we reviewed the factors that affect the market and non-market value of legumes and the relevant agricultural policies. We characterized the decline in legume cropping as an outcome of the dominance of economic forces that favour specialization of production systems over diversification. We found that the value of market outputs of legumes per unit area is relatively low and volatile, with a 25–78 % variation in pea gross margins, which reduces market competitiveness. We observed that the value of system-internal outputs of legumes such as the nitrogen fixed, of 130 to 153 kg N ha−1; crop protection services that reduce agrochemical costs, by 20–25 % in cereals; and yield enhancements of subsequent crops, of 0.2 to 1.6 t ha−1 in cereals, are often underestimated. In addition, markets fail to translate external effects of legumes such as biodiversity enhancement, reduction in emissions, of up to 50 % in N2O, and soil improvements into economic benefits. Current policies support legumes through selected mechanisms such as ecological focus areas, agri-environmental programmes and sparse coupled support measures. Domestic cultivation of legumes could be supported through trade policies such as import restrictions on genetically modified soybean or new mechanisms to appreciate non-market outputs including payments for ecosystem services and carbon markets. In addition, development of new value chains, niche markets, scaling-up of plant breeding efforts and dissemination of information is required. © 2016, INRA and Springer-Verlag France.