Selected Farm level models and tools forex-ante analysis of impacts of policiesrelated to circular agriculture : Deliverable D2: Progress report project KB-1-2A-4 : models across scale

Abstract

In this report we present a model toolbox consisting of the Bio-Economic Farm Models (BEFMs) DairyWise and Farmdyn together with tools that focus on specific farm management aspects to analyse integrated aspects of circular agriculture at farm level. Based on a conceptual model regarding relevant policy questions, indicators and model requirements, knowledge and modelling gaps are pointed at. It is concluded that combined model use can overcome part of the modelling gaps, but not all. The combined model use is demonstrated analysing the impact of a tax on chemical fertiliser on a dairy farm on sandy soil and an arable farm on clay soil. The report ends with recommendations regarding research directions in the field of modelling circular agriculture aspects at farm level, sharing and harmonising key modules and investments in quality and quantity of different networks of model developers and users. We also give recommendations for researchers and modelers who are looking for possibilities of combined model use.

Model Collaboration between Farm Level Models with Application on Dutch Dairy and Arable Farms Regarding Circular Agricultural Policy

“…1 Plant available N from manure and mineral fertiliser. 2 Yield after harvest losses, before conservation and feeding losses.…”

“…Circular agriculture aspects and indicators covered by the BEFMs and the NA tool comprise the use of external inputs (e.g., mineral fertilisers, concentrates, and crop protection agents), nutrient and GHG emissions, economy, organic matter supply, and share of permanent grassland. This is rather incomplete compared to the conceptual model as described in [2].…”

“…A conceptual model to analyse circularity at the farm level has been presented in [2]. This conceptual model was described in terms of relevant policy questions, indicators, and farm model requirements.…”

“…These models allow integrated assessment of economic, agronomic, biophysical, and environmental effects of policy measures related to circular agriculture at farm level. However, given the wide range and complexity of policy questions, the large number of indicators and the interrelationships of themes and scales related to circular agriculture, individual BEFMs cannot fulfil all the necessary requirements [2]. Model collaboration helps to solve this problem and to broaden the scope of the analysis [3,4].…”

“…1 Applied organic matter (organic manure, crop residues) that is still present after one year 2. CO 2 direct: fuel consumption; CO 2 -indirect: fertiliser use; N 2 O direct: use of N in manure and fertiliser and N in crop residues; N 2 O indirect: resulting from NH 3 and NO 3 emission.…”