Lénaïc Pardon1, Paul N. Nelson2, Benoît Gabrielle3, Neil I. Huth4, Nathalie Saint- Geours5, Bernard Dubos1, Jean Ollivier1, Raphaël Marichal1,6, Jean-Pierre Caliman6, Ni’matul Khasanah7, Murom Banabas8, and Cécile Bessou1
1CIRAD, UPR Systèmes de pérennes, F-34398 Montpellier, France
2College of Science and Engineering, James Cook University, Cairns, Australia
3Agro ParisTech, INRA, Université Paris-Saclay, UMR EcoSys, 78850, Thiverval-Grignon, France
4CSIRO, Toowoomba, Australia
5ITK, CEEI CAP ALPHA Avenue de l’Europe, 34830 Clapiers, France
6SMART Research Institute, Jl. Tengku Umar 19, Pekanbaru 28112,Indonesia
7World Agroforestry Centre (ICRAF), Southeast Asia Regional Programme, Bogor, Indonesia
8Papua New Guinea Oil Palm Research Association, Dami, Papua New Guinea
Improving palm oil production sustainability is crucial for both reducing negative environmental impacts (e.g. Carlson et al., 2012 for greenhouse gas emissions), and ensuring food security (Corley and Tinker, 2015; Rival and Levang, 2014). The application of nitrogen (N) fertilisers is a major source of environmental impacts associated with oil palm cultivation (Choo et al., 2011). Environmental assessments of palm oil production are useful to quantify impacts of N losses and identify potential improvements of management practices. However, such environmental assessments tend to be uncertain as there is no model specific to oil palm, sensitive to agricultural practices, which simulates all the N losses.
We performed three steps to synthesise the available knowledge on measurements and modelling of N fluxes and losses in oil palm plantations. The study focused on industrial oil palm plantations on mineral soils. Firstly, we conducted a literature review of all the existing knowledge on N fluxes and losses in plantations. Secondly, we compared 11 existing models that may be used to predict N losses in plantations. Thirdly, we performed an in-depth Morris’s sensitivity analysis of one of these models, the APSIM-Oil palm process-based model (Huth et al., 2014).
In the literature review, we estimated the main N fluxes and N losses in oil palm plantations, we identified their drivers, and we pointed out the research gaps (Pardon et al., 2016a). In the model comparison, we identified the models ability to capture peculiarities of the oil palm system, their limits, and the main uncertainties in modelling (Pardon et al., 2016b). In the sensitivity analysis, we identified the key drivers of N losses and yield of APSIM-Oil palm model (Pardon et al., 2017).
This research constitutes a comprehensive synthesis of the available knowledge and models for N fluxes and losses in oil palm plantations. It provides useful insights for oil palm managers, experimentalists and modellers, to help identify management practices to reduce N losses in the environment, lacks of field measurements and modelling challenges. Finally, these results were used as a base for the building of IN-Palm, an agri-environmental indicator to estimate N losses in oil palm plantations.