Simultaneously enhancing ecosystem services provided by biodiversity below and above ground is recommended to reduce dependence on chemical pesticides and mineral fertilisers in agriculture. However, consequences for crop yield have been poorly evaluated. Above ground, increased landscape complexity is assumed to enhance biological pest control, whereas below ground, soil organic carbon is a proxy for several yield-supporting services. In a field experiment replicated in 114 fields across Europe, we found that fertilisation had the strongest positive effect on yield, but hindered simultaneous harnessing of below- and above-ground ecosystem services. We furthermore show that enhancing natural enemies and pest control through increasing landscape complexity can prove disappointing in fields with low soil services or in intensively cropped regions. Thus, understanding ecological interdependences between land use, ecosystem services and yield is necessary to promote more environmentally friendly farming by identifying situations where ecosystem services are maximised and agrochemical inputs can be reduced.

Soil organic matter (SOM) is declining in most agricultural ecosystems, impacting multiple ecosystem services including erosion and flood prevention, climate and greenhouse gas regulation as well as other services that underpin crop production, such as nutrient cycling and pest control. Ecological intensification aims to enhance crop productivity by including regulating and supporting ecosystem service management into agricultural practices. We investigate the potential for increased SOM to support the ecological intensification of arable systems by reducing the need for nitrogen fertiliser application and pest control. Using a large-scale European field trial implemented across 84 fields in 5 countries, we tested whether increased SOM (using soil organic carbon as a proxy) helps recover yield in the absence of conventional nitrogen fertiliser and whether this also supports crops less favourable to key aphid pests. Greater SOM increased yield by 10%, but did not offset nitrogen fertiliser application entirely, which improved yield by 30%. Crop pest responses depended on species: Metopolophium dirhodum were more abundant in fertilised plots with high crop biomass, and although population growth rates of Sitobion avenae were enhanced by nitrogen fertiliser application in a cage trial, field populations were not affected. We conclude that under increased SOM and reduced fertiliser application, pest pressure can be reduced, while partially compensating for yield deficits linked to fertiliser reduction. If the benefits of reduced fertiliser application and increased SOM are considered in a wider environmental context, then a yield cost may become acceptable. Maintaining or increasing SOM is critical for achieving ecological intensification of European cereal production.

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Integrated pest management (IPM), a worldwide agricultural strategy, contains methods to control or manage agricultural pests and diseases in a more efficient way, and consequently, to obtain better quality raw materials for food production. The engagement and practice of farmers play a key role in the success of this strategy. Since January 1, 2014, Poland and other European Union countries have been obligated to apply the principles of IPM. This paper shows the results of surveys conducted in 280 randomly selected farms the year before and the year following mandatory IPM implementation. The aim of this study was to gather information about farmers’ knowledge of IPM and the most commonly used plant protection methods. Our results show that law regulations do not significantly change agricultural practice. Among the non-chemical methods farmers most often comply with are: implementing the agrochemical calendar, sowing healthy material, destroying volunteer plants, rotating crop, applying balanced fertilizer, plowing stubble and preventing excess nitrogen. Integrated plant protection is not possible without proper knowledge of diseases. This factor needs improvement in Poland. The average Polish farmer lacks the knowledge about basic cereal diseases such as powdery mildew or brown rust, though larger farm operators tend to be more knowledgeable. The results of this survey demonstrate the necessity to provide informative farmer training campaigns to promote on-farm application of IPM and to improve the knowledge of disease issues.

Common Agricultural Policy (CAP) reform in the European Union introduced a new element: greening. The aim of greening is to support the environment and create non-productive value in agriculture. The main element of greening is the Ecological Focus Area (EFA) meaning that a portion of farmland area has to be designed for environmental purposes. This article consists of an evaluatation of greening and its elements in the first year CAP reform has come into force. Surveys were used as a tool to gather information about farm characteristics, ways to meet greening requirements as well as the opinions of farmers as to changes in direct subsidies and greening obligations. The research was conducted in 2015 directly interviewing 290 farmers from the whole of Poland. The farmers interviewed lived in different parts of the country and had different size farms. Data was prepared with the use of spreadsheets and were analysed using the R statistical program and the "gmodel" and "vcd" statistical packages were used during the calculations. Polish farmers are against greening. Greening does not significantly change the way farmers run their farms. They choose the cheapest options of EFA which are usually not the best for the environment. Furthermore, farmers have to bear the cost of introducing the new elements themselves. Despite a high number of environmental and agricultural advantages offered by new farming methods, crop rotation and after-crop sowing duty, CAP reform is assessed in a negative light. As a result of negative opinions held by farmers due to the lack of subsidies, farmers may not continue greening practices in the future.