Jens Erik Ørum

The value of precision for image-based decision support in weed management

Decision support methodologies in precision agriculture should integrate the different dimensions composing the added complexity of operational decision problems. Special attention has to be given to the adequate knowledge extraction techniques for making sense of the collected data, processing the information for assessing decision makers and farmers in the efficient and sustainable management of the field. Focusing on weed management, the integration of operational aspects for weed spraying is an open challenge for modeling the farmers’ decision problem, identifying satisfactory solutions for the implementation of automatic weed recognition procedures. The objective of this paper is to develop a decision support methodology for detecting the undesired weed from aerial images, building an image-based viewpoint consisting in relevant operational knowledge for applying precision spraying. In this way, it is possible to assess the potential herbicide cost reductions of increased precision at the spraying device, selecting the appropriate weed precision spraying technology. Findings from this study indicate that the potential gains and marginal cost reductions of herbicides decrease significantly with increased precision in spraying.

Farm economic and environmental effects of reduced tillage.

Abstract Reduced tillage is an increasingly popular farming method. In some countries it is used on up to 50% of the total cropland, but in Denmark the area with reduced tillage is only 10%. The benefit from reduced tillage is a higher marginal profit per ha due to an increased productivity of labour and machinery, but there are also environmental benefits e.g. reduced phosphorus and nitrogen losses as well as reduced Greenhouse Gas emissions. In a recent Danish research project, the economic and environmental effects of reduced tillage have been analysed by using a farm economic crop production model, simulating arable farmers’ rational adjustment to new technologies, prices and regulations. The conclusion is that reduced tillage increases the profits by € 67–111 per ha according to farm size and it reduces the use of fuel per ha. With no changes in the crop rotation, the nitrogen surplus is unaffected and pesticide use is increased. However, the optimal adaptation to reduced-tillage systems includes a change in the crop rotation increasing the share of spring cereals. As a result of this adjustment, the nitrogen surplus is reduced and the increase in pesticide use is, to some extent, mitigated. Even when no increase in pesticide use is permitted the reduced tillage system seems to be more profitable than conventional tillage systems.

Economic Incentives and Alternative Nitrogen Regulation Schemes: A Spatial Sector Economic Modelling Approach

The objective of this chapter is to investigate economic incentives associated with changes in nitrogen regulation, including the distribution between farm types and geographically. The analysis is carried out on a partial equilibrium simulation model of the Danish agricultural sector—ESMERALDA. The model is based on farm-level production and economic data for all Danish farms, which allow the analysis of spatial aspects related to the alternative regulations, in terms of environmental (in terms of nitrogen use) and economic effects. Results of the model analyses suggest that replacing the current flat-rate quota on nitrogen input on all farms with a more differentiated quota on nitrogen leaching will in particular be binding for crop and pig farms in environmentally sensitive areas.

Economics of Site-Specific and Variable-Dose Herbicide Application

Site-specific application of pesticides has so far focused mainly on herbicides. The purpose of precision farming technologies in relation to herbicide use is to reduce herbicide cost and environmental impact from spraying, but at the same time to achieve acceptable weed control. Another purpose is to increase the spraying capacity, to reduce the number of sprayer refills, and finally to minimize time spent on weed monitoring. In this chapter the relevance and profitability of four precision herbicide application technologies, two weed detection technologies and a low dose decision support system (DSS) is analysed. With a low dose herbicide, cost can be reduced by 20–50%. It requires, however, proper monitoring of weeds, which can be a time-consuming task that again requires that the farmer is able to identify the dominant weed species. The current development of high-speed camera and software systems can help to detect and map individual weeds, and some systems have proved to be cost effective for certain weeds.