In 2007, I started a BSc in Plant Sciences at Wageningen University, and continued with an MSc in Crop Sciences in 2010. During my studies I specialised in crop modelling and crop management. Quantification and analysis of yield gaps were important components in both the BSc and MSc.

After graduation in 2012, I started a PhD research in the Animal Production Systems group and the Plant Production Systems group of Wageningen University. This research aimed to apply the methods for quantification and analysis of yield gaps, which are widely used in crop sciences, to livestock production. In the crop sciences, yield gaps are quantified based on concepts of production ecology. Concepts of production ecology distinguish three production levels: potential, limited, and actual production. I specified concepts of production ecology for livestock production in more detail than previously done, and developed a framework to calculate potential and feed-limited livestock production.

Next, a mechanistic model to simulate potential and feed-limited production of beef cattle was developed (LiGAPS-Beef), which allows to quantify and analyse yield gaps at herd level. This model was validated with experimental data, and turned out to simulate average daily gain fairly well. Integration of feed crop and livestock production started after the developement of this model. Combining feed crops and cattle allows to quantify beef or live weight production per hectare (used for feed crops) per year. We integrated crop and livestock models to simulate beef production in the Charolais region of France. This approach allowed to quantify yield gaps of beef cattle per hectare per year, and to identify the major biophysical factors contributing to the yield gap in the Charolais region. Furthermore, I investigated the effect of climate change on beef production in the Charolais area. The PhD thesis that came forth of this research provided a generic method to assess and analyse yield gaps in livestock systems and feed-crop livestock systems.

My current focus is to apply the generic method described in the thesis to more case studies, including developing countries, and to extend the modelling to dairy cows as well. My current research projects are described below.    

Postdoctoral project 'Investing in Sustainable Livestock Production'

Global demand for animal and crop products is expected to increase in future. Production of more animal and crop products per unit of land is a strategy to meet the increased demand for food. Some regions in the world have yields close to the potential, while in others production is only a fraction of what can be potentially produced. Quantification of yield gaps is thus essential to get insight how much current production levels can be increased. This project aims to quantify and analyse yield gaps for beef cattle in Uruguay and for dairy cattle in Ethiopia and Bangladesh, and to investigate the effects of improvement options for these three countries.

Yield gaps are quantified by using mechanistic crop and livestock models. The model LiGAPS-Beef (Livestock simulator for Generic analysis of Animal Production Systems - Beef cattle) is used to simulate potential and feed-limited production of beef cattle. The model LiGAPS-Dairy is developed to simulate the theoretical production levels of dairy cattle. Crop growth models and data from the Global Yield Gap Atlas (www.yieldgap.org) are used to quantify yield gaps for feed crops. Based on yield gap analysis, improvement options for farming systems will be simulated.

Within this project, I collaborate with the WorldBank and the Food and Agriculture Organisation (FAO) of the United Nations. This research is to be published in a FAO report and a scientific paper.

Project 'AnimalFuture: Steering Animal Production Systems towards Sustainable Future'

Farmers in Europe are under pressure to increase their productivity and competitiveness in the global trade of agricultural products. Increasing productivity and competitiveness can be achieved by adopting innovations. Innovations affect the environmental, economic, and social sustainability of farms. This project aims to make European livestock sector more resilient and competitive by assessing the effects of innovations, including their effect on sustainability. Modelling can help to get more insight in the synergies and trade-offs in sustainability indicators when introducing innovations.

Within this large European project (8  universties and research centres involved) my tasks are:

• To make an inventory of existing models for livestock and farms with livestock applicable to the European livestock sector
• Evaluate to what extent and how the available models assess productivity and sustainability
• Integrate available models to simulate the effect of innovations on productivity and environmental, economic, and social sustainability   

Courses:

• YAS10306, Introduction Animal Sciences (Period 1 2017/2018). Supervision of a group of students conducting a farm survey.
• SOQ 33306, Integrated Natural Resource Management in Organic Agriculture (Period 2 2017/2018). Assistance in computer practicals and field excursions, responsible for the livestock component of this course.
• During the last years I have contributed to the following courses:
  • CSA 10806, Introduction Quantitative Agroecology
  • APS 20806, Systems Approach in Animal Sciences
  • APS 21803, Global & Sustainable Animal Production in the 21st Century
  • PPS 51802, Future Food Production: Crops (MOOC)