Potential economic gains from using forage legumes in organic livestock systems in northern Europe

This report was presented at the UK Organic Research 2002 Conference of the Colloquium of Organic Researchers (COR). Forage legumes, with their ability to fix nitrogen biologically, seem especially attractive for organic livestock production. In an attempt to assess their true potential, this study draws on a four-year trial conducted at 12 sites in northern Europe with four different forage legumes. One third of the sites were managed as organic systems, with the harvested forage being fed as silage to dairy cows. Based on the trial results, an economic assessment has been made of the potential of forage legumes to improve the competitive edge of organic dairy systems, relative to conventional grass-based ones. Although the results suggest that the organic milk price premium plays a major role in determining the comparative profitability of organic dairy systems, the use of forage legumes also gives a significant cost advantage to organic production

Utilising the concept of nutrients as a currency within organic farming system

This report was presented at the UK Organic Research 2002 Conference.Within organic systems, the successful management of nutrients at the field level is crucial for maximising production and minimising the environmental impacts. This requires that the farmer makes the best possible use of nutrients excreted by the grazing or housed livestock. In addition, the farmer must successfully manage the nutrients built-up in the ley phase of the crop rotation over the whole of the arable phase period. To analyse these complex flows, a nutrient budget model has been developed that describes the spatial and temporal flows within the organic farming system. The concept is analogous to treating nutrients as a currency where the flow of nutrients represents a cashflow. A spatial nutrient budget permits the analyses of the performance of the nutrient flows to be examined for the housing, manure, livestock, rotational land and permanent pasture to be analysed separately. This analysis will allow the farmer to better understand the weaknesses in the system, and hence take preventative measures

A framework for assessing crop production from rotations

This report was presented at the UK Organic Research 2002 Conference of the Colloquium of Organic Researchers (COR). Organic farming systems rely on the management of biological cycles for the provision of nutrients, which are crucial to maximising the production from the system. Rotations based on the use of grass-legume leys are central to the concept of organic farming systems, because they have the potential to support both animal production, and a subsequent, exploitative, arable cropping phase. A major challenge in organic farming is managing the supply of nitrogen, since it has a key role in governing both productivity and environmental impact. Hence, within a rotational system, there is a need to understand the complex interactions that are occurring between crop species and management, livestock production system and the impact of soil and climate on these processes. To understand these interactions, a framework is being developed for rotational farming systems that describes the soil nitrogen, crop growth and livestock production. The framework must address questions that are relevant to researchers and extensions workers. Typical questions relate to the management of nutrients in the short and long-term. Additionally, there are concerns over the impact of weeds, pests and diseases on productivity, as well as the impact of adopting new strategies or crops on the farming system

A Guide to Nutrient Budgeting on Organic Farms

The leaflet gives practical guidance on using data and calculating farm-gate nutrient budgets with sections on soil analysis, nutrient inputs, nutrient losses and flows, nitrogen fixation through leys and how inputs and outputs from organic manures and livestock feed can be recorded. It contains one example table of a farm-gate annual nutrient budget for a mixed cattle and arable farm. The tool is specific to organic farming. It was drafted for the UK but has relevance in other countries

Calibration and validation of the DNDC model to estimate nitrous oxide emissions and crop productivity for a summer maize-winter wheat double cropping system in Hebei, China

We thank Dr. Min Liu for providing the field measurement data and Prof. Xinping Chen for providing the data of crop yields. We acknowledge the financial supported from the N Circle - a BBSRC-Newton Funded project (BB/N013484/1), the National Natural Science Foundation of China (41830751) and EU Horizon 2020 programme (SuperG).Peer reviewedPostprin

Perception vs practice:Farmer attitudes towards and uptake of IPM in Scottish spring barley

Integrated Pest Management (IPM) offers a suite of ways by which to reduce the need for pesticide use, thus minimising environmental damage and pathogen resistance build-up in crop production. Farmers and agronomists active in the Scottish spring barley sector were surveyed to determine the extent to which they currently use or are open to implementing three IPM measures – varietal disease resistance, crop rotation, and forecasting disease pressure – in order to control three important fungal diseases. Overall, the survey results demonstrate that farmers and agronomists are open to using the three IPM techniques. However, gaps between actual and perceived recent practice were large: despite over 60% of farmers stating that they sowed varieties highly resistant to Rhynchosporium or Ramularia, less than one third of reportedly sown varieties were highly resistant to these diseases. Similarly, over 80% of farmers indicated that they used crop rotations, yet 66% of farmers also reported sowing consecutive barley often/always. Further research is needed in order to understand why these gaps exist, and how they can be reduced in future in order to increase IPM uptake and optimise pesticide use

An interdisciplinary method for assessing IPM potential:Case study in Scottish spring barley

A method is proposed which considers Integrated Pest Management (IPM) through several lenses, in order to obtain a more holistic view of the potential for IPM, and is described using a case study of Scottish spring barley. Long-term experimental field trial databases are used to determine which management methods are best suited to the system at hand. Stakeholder engagement provides insight into which of these methods are most likely to be taken up by farmers. Finally, a database of commercial practice allows an estimate of the potential for improving management patterns, based on current levels of IPM uptake across a wider sample of Scottish farmers. Together, these diverse sources of information give a more complete view of a complex system than any individual source could and allow the identification of IPM methods which are robust, practical, and not already in widespread use in this system. Bringing together these sources of information may be of particular value for policy and other decision makers, who need information about strategies which are both practical and likely to have a large positive impact. In the case of Scottish spring barley, there is good potential to reduce the need for fungicide use through the increased use of highly resistant barley varieties

Estimating the soil N2O emission intensity of croplands in northwest Europe

The application of nitrogenous fertilisers to agricultural soils is a major source of anthropogenic N2O emissions. Reducing the nitrogen (N) footprint of agriculture is a global challenge that depends, among other things, on our ability to quantify the N2O emission intensity of the world's most widespread and productive agricultural systems. In this context, biogeochemistry (BGC) models are widely used to estimate soil N2O emissions in agroecosystems. The choice of spatial scale is crucial because larger-scale studies are limited by low input data precision, while smaller-scale studies lack wider relevance. The robustness of large-scale model predictions depends on preliminary and data-demanding model calibration/validation, while relevant studies often omit the performance of output uncertainty analysis and underreport model outputs that would allow a critical assessment of results. This study takes a novel approach to these aspects. The study focuses on arable eastern Scotland – a data-rich region typical of northwest Europe in terms of edaphoclimatic conditions, cropping patterns and productivity levels. We used a calibrated and locally validated BGC model to simulate direct soil N2O emissions along with NO3 leaching and crop N uptake in fields of barley, wheat and oilseed rape. We found that 0.59&thinsp;% (±0.36) of the applied N is emitted as N2O while 37&thinsp;% (±6) is taken up by crops and 14&thinsp;% (±7) is leached as NO3. We show that crop type is a key determinant of N2O emission factors (EFs) with cereals having a low (mean EF&lt;0.6&thinsp;%), and oilseed rape a high (mean EF=2.48&thinsp;%), N2O emission intensity. Fertiliser addition was the most important N2O emissions driver suggesting that appropriate actions can reduce crop N2O intensity. Finally, we estimated a 74&thinsp;% relative uncertainty around N2O predictions attributable to soil data variability. However, we argue that higher-resolution soil data alone might not suffice to reduce this uncertainty.</p