Mechanical weeding enhances ecosystem multifunctionality and profit in industrial oil palm

Oil palm is the most productive oil crop, but its high productivity is associated with conventional management (that is, high fertilization rates and herbicide application), causing deleterious environmental impacts. Using a 2^2 factorial experiment, we assessed the effects of conventional vs reduced (equal to nutrients removed by fruit harvest) fertilization rates and herbicide vs mechanical weeding on ecosystem functions, biodiversity and profitability. Analysing across multiple ecosystem functions, mechanical weeding exhibited higher multifunctionality than herbicide treatment, although this effect was concealed when evaluating only for individual functions. Biodiversity was also enhanced, driven by 33% more plant species under mechanical weeding. Compared with conventional management, reduced fertilization and mechanical weeding increased profit by 12% and relative gross margin by 11% due to reductions in material costs, while attaining similar yields. Mechanical weeding with reduced, compensatory fertilization in mature oil palm plantations is a tenable management option for enhancing ecosystem multifunctionality and biodiversity and increasing profit, providing win–win situations.

Najeeb Al-Amin Iddris, Greta Formaglio, Carola Paul, Volker von Groß, Guantao Chen, Andres Angulo-Rubiano, Dirk Berkelmann, Fabian Brambach, Kevin F. A. Darras, Valentyna Krashevska, Anton Potapov, Arne Wenzel, Bambang Irawan, Muhammad Damris, Rolf Daniel, Ingo Grass, Holger Kreft, Stefan Scheu, Teja Tscharntke, Aiyen Tjoa, Edzo Veldkamp, Marife D. Corre